bgfx/src/renderer_gl.cpp

/*
 * Copyright 2011-2013 Branimir Karadzic. All rights reserved.
 * License: http://www.opensource.org/licenses/BSD-2-Clause
 */

#include "bgfx_p.h"

#if (BGFX_CONFIG_RENDERER_OPENGLES2|BGFX_CONFIG_RENDERER_OPENGLES3|BGFX_CONFIG_RENDERER_OPENGL)
#	include "renderer_gl.h"
#	include <bx/timer.h>
#	include <bx/uint32_t.h>

namespace bgfx
{
	static char s_viewName[BGFX_CONFIG_MAX_VIEWS][256];

	static const GLenum s_primType[] =
	{
		GL_TRIANGLES,
		GL_LINES,
		GL_POINTS,
	};

	static const char* s_attribName[Attrib::Count] =
	{
		"a_position",
		"a_normal",
		"a_tangent",
		"a_color0",
		"a_color1",
		"a_indices",
		"a_weight",
		"a_texcoord0",
		"a_texcoord1",
		"a_texcoord2",
		"a_texcoord3",
		"a_texcoord4",
		"a_texcoord5",
		"a_texcoord6",
		"a_texcoord7",
	};

	static const char* s_instanceDataName[BGFX_CONFIG_MAX_INSTANCE_DATA_COUNT] =
	{
		"i_data0",
		"i_data1",
		"i_data2",
		"i_data3",
		"i_data4",
	};

	static const GLenum s_attribType[AttribType::Count] =
	{
		GL_UNSIGNED_BYTE,
		GL_SHORT,
		GL_HALF_FLOAT,
		GL_FLOAT,
	};

	struct Blend
	{
		GLenum m_src;
		GLenum m_dst;
		bool m_factor;
	};

	static const Blend s_blendFactor[] =
	{
		{ 0,                           0,                           false }, // ignored
		{ GL_ZERO,                     GL_ZERO,                     false },
		{ GL_ONE,                      GL_ONE,                      false },
		{ GL_SRC_COLOR,                GL_SRC_COLOR,                false },
		{ GL_ONE_MINUS_SRC_COLOR,      GL_ONE_MINUS_SRC_COLOR,      false },
		{ GL_SRC_ALPHA,                GL_SRC_ALPHA,                false },
		{ GL_ONE_MINUS_SRC_ALPHA,      GL_ONE_MINUS_SRC_ALPHA,      false },
		{ GL_DST_ALPHA,                GL_DST_ALPHA,                false },
		{ GL_ONE_MINUS_DST_ALPHA,      GL_ONE_MINUS_DST_ALPHA,      false },
		{ GL_DST_COLOR,                GL_DST_COLOR,                false },
		{ GL_ONE_MINUS_DST_COLOR,      GL_ONE_MINUS_DST_COLOR,      false },
		{ GL_SRC_ALPHA_SATURATE,       GL_ONE,                      false },
		{ GL_CONSTANT_COLOR,           GL_CONSTANT_COLOR,           true  },
		{ GL_ONE_MINUS_CONSTANT_COLOR, GL_ONE_MINUS_CONSTANT_COLOR, true  },
	};

	static const GLenum s_blendEquation[] =
	{
		GL_FUNC_ADD,
		GL_FUNC_SUBTRACT,
		GL_FUNC_REVERSE_SUBTRACT,
		GL_MIN,
		GL_MAX,
	};

	static const GLenum s_depthFunc[] =
	{
		0, // ignored
		GL_LESS,
		GL_LEQUAL,
		GL_EQUAL,
		GL_GEQUAL,
		GL_GREATER,
		GL_NOTEQUAL,
		GL_NEVER,
		GL_ALWAYS,
	};

	static const GLenum s_stencilFunc[] =
	{
		0, // ignored
		GL_LESS,
		GL_LEQUAL,
		GL_EQUAL,
		GL_GEQUAL,
		GL_GREATER,
		GL_NOTEQUAL,
		GL_NEVER,
		GL_ALWAYS,
	};

	static const GLenum s_stencilOp[] =
	{
		GL_ZERO,
		GL_KEEP,
		GL_REPLACE,
		GL_INCR_WRAP,
		GL_INCR,
		GL_DECR_WRAP,
		GL_DECR,
		GL_INVERT,
	};

	static const GLenum s_stencilFace[] =
	{
		GL_FRONT_AND_BACK,
		GL_FRONT,
		GL_BACK,
	};

	struct RenderTargetColorFormat
	{
		GLenum m_internalFmt;
		GLenum m_type;
		uint8_t m_bpp;
	};

	// Specifies the internal format of the texture.
	// Must be one of the following symbolic constants:
	// GL_ALPHA, GL_LUMINANCE, GL_LUMINANCE_ALPHA, GL_RGB, GL_RGBA.
	static const RenderTargetColorFormat s_colorFormat[] =
	{
		{ 0,           0,                               0 }, // ignored
		{ GL_RGBA8,    GL_UNSIGNED_BYTE,               32 },
		{ GL_RGB10_A2, GL_UNSIGNED_INT_2_10_10_10_REV, 32 },
		{ GL_RGBA16,   GL_UNSIGNED_SHORT,              64 },
		{ GL_RGBA16F,  GL_HALF_FLOAT,                  64 },
		{ GL_R16F,     GL_HALF_FLOAT,                  16 },
		{ GL_R32F,     GL_FLOAT,                       32 },
	};

	static const GLenum s_depthFormat[] =
	{
		0, // ignored
		0,
	};

	static const GLenum s_textureAddress[] =
	{
		GL_REPEAT,
		GL_MIRRORED_REPEAT,
		GL_CLAMP_TO_EDGE,
	};

	static const GLenum s_textureFilterMag[] =
	{
		GL_LINEAR,
		GL_NEAREST,
		GL_LINEAR,
	};

	static const GLenum s_textureFilterMin[][3] =
	{
		{ GL_LINEAR,  GL_LINEAR_MIPMAP_LINEAR,  GL_NEAREST_MIPMAP_LINEAR  },
		{ GL_NEAREST, GL_LINEAR_MIPMAP_NEAREST, GL_NEAREST_MIPMAP_NEAREST },
		{ GL_LINEAR,  GL_LINEAR_MIPMAP_LINEAR,  GL_NEAREST_MIPMAP_LINEAR  },
	};

	struct TextureFormatInfo
	{
		GLenum m_internalFmt;
		GLenum m_fmt;
		GLenum m_type;
		bool m_supported;
	};

	static TextureFormatInfo s_textureFormat[TextureFormat::Count] =
	{
		{ GL_COMPRESSED_RGBA_S3TC_DXT1_EXT,            GL_COMPRESSED_RGBA_S3TC_DXT1_EXT,            GL_ZERO,                        false }, // BC1
		{ GL_COMPRESSED_RGBA_S3TC_DXT3_EXT,            GL_COMPRESSED_RGBA_S3TC_DXT3_EXT,            GL_ZERO,                        false }, // BC2
		{ GL_COMPRESSED_RGBA_S3TC_DXT5_EXT,            GL_COMPRESSED_RGBA_S3TC_DXT5_EXT,            GL_ZERO,                        false }, // BC3
		{ GL_COMPRESSED_LUMINANCE_LATC1_EXT,           GL_COMPRESSED_LUMINANCE_LATC1_EXT,           GL_ZERO,                        false }, // BC4
		{ GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT,     GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT,     GL_ZERO,                        false }, // BC5
		{ GL_ETC1_RGB8_OES,                            GL_ETC1_RGB8_OES,                            GL_ZERO,                        false }, // ETC1
		{ GL_COMPRESSED_RGB8_ETC2,                     GL_COMPRESSED_RGB8_ETC2,                     GL_ZERO,                        false }, // ETC2
		{ GL_COMPRESSED_RGBA8_ETC2_EAC,                GL_COMPRESSED_RGBA8_ETC2_EAC,                GL_ZERO,                        false }, // ETC2A
		{ GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2, GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2, GL_ZERO,                        false }, // ETC2A1
		{ GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG,          GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG,          GL_ZERO,                        false }, // PTC12
		{ GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG,          GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG,          GL_ZERO,                        false }, // PTC14
		{ GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG,         GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG,         GL_ZERO,                        false }, // PTC12A
		{ GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG,         GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG,         GL_ZERO,                        false }, // PTC14A
		{ GL_COMPRESSED_RGBA_PVRTC_2BPPV2_IMG,         GL_COMPRESSED_RGBA_PVRTC_2BPPV2_IMG,         GL_ZERO,                        false }, // PTC22
		{ GL_COMPRESSED_RGBA_PVRTC_4BPPV2_IMG,         GL_COMPRESSED_RGBA_PVRTC_4BPPV2_IMG,         GL_ZERO,                        false }, // PTC24
		{ GL_ZERO,                                     GL_ZERO,                                     GL_ZERO,                        true  }, // Unknown
		{ GL_LUMINANCE,                                GL_LUMINANCE,                                GL_UNSIGNED_BYTE,               true  }, // L8
		{ GL_RGBA,                                     GL_RGBA,                                     GL_UNSIGNED_BYTE,               true  }, // BGRA8
		{ GL_RGBA16,                                   GL_RGBA,                                     GL_UNSIGNED_BYTE,               true  }, // RGBA16
		{ GL_RGBA16F,                                  GL_RGBA,                                     GL_HALF_FLOAT,                  true  }, // RGBA16F
		{ GL_RGB565,                                   GL_RGB,                                      GL_UNSIGNED_SHORT_5_6_5,        true  }, // R5G6B5
		{ GL_RGBA4,                                    GL_RGBA,                                     GL_UNSIGNED_SHORT_4_4_4_4,      true  }, // RGBA4
		{ GL_RGB5_A1,                                  GL_RGBA,                                     GL_UNSIGNED_SHORT_5_5_5_1,      true  }, // RGB5A1
		{ GL_RGB10_A2,                                 GL_RGBA,                                     GL_UNSIGNED_INT_2_10_10_10_REV, true  }, // RGB10A2
	};

	struct Extension
	{
		enum Enum
		{
			ANGLE_instanced_arrays,
			ANGLE_translated_shader_source,
			APPLE_texture_format_BGRA8888,
			ARB_debug_output,
			ARB_depth_clamp,
			ARB_ES3_compatibility,
			ARB_framebuffer_sRGB,
			ARB_get_program_binary,
			ARB_half_float_vertex,
			ARB_instanced_arrays,
			ARB_multisample,
			ARB_sampler_objects,
			ARB_seamless_cube_map,
			ARB_texture_float,
			ARB_texture_multisample,
			ARB_texture_swizzle,
			ARB_timer_query,
			ARB_vertex_array_object,
			ARB_vertex_type_2_10_10_10_rev,
			ATI_meminfo,
			CHROMIUM_framebuffer_multisample,
			CHROMIUM_texture_compression_dxt3,
			CHROMIUM_texture_compression_dxt5,
			EXT_bgra,
			EXT_blend_color,
			EXT_blend_minmax,
			EXT_blend_subtract,
			EXT_framebuffer_blit,
			EXT_framebuffer_sRGB,
			EXT_occlusion_query_boolean,
			EXT_texture_compression_dxt1,
			EXT_texture_compression_latc,
			EXT_texture_compression_rgtc,
			EXT_texture_compression_s3tc,
			EXT_texture_filter_anisotropic,
			EXT_texture_format_BGRA8888,
			EXT_texture_sRGB,
			EXT_texture_storage,
			EXT_texture_swizzle,
			EXT_texture_type_2_10_10_10_REV,
			EXT_timer_query,
			IMG_multisampled_render_to_texture,
			IMG_read_format,
			IMG_shader_binary,
			IMG_texture_compression_pvrtc,
			IMG_texture_compression_pvrtc2,
			IMG_texture_format_BGRA8888,
			NVX_gpu_memory_info,
			OES_compressed_ETC1_RGB8_texture,
			OES_depth_texture,
			OES_get_program_binary,
			OES_read_format,
			OES_rgb8_rgba8,
			OES_standard_derivatives,
			OES_texture_float,
			OES_texture_float_linear,
			OES_texture_half_float,
			OES_texture_half_float_linear,
			OES_vertex_array_object,
			OES_vertex_half_float,
			OES_vertex_type_10_10_10_2,

			Count
		};

		const char* m_name;
		bool m_supported;
		bool m_initialize;
	};

	static Extension s_extension[Extension::Count] =
	{
		{ "GL_ANGLE_instanced_arrays",             false,                             true  },
		{ "GL_ANGLE_translated_shader_source",     false,                             true  },
		{ "GL_APPLE_texture_format_BGRA8888",      false,                             true  },
		{ "GL_ARB_debug_output",                   BGFX_CONFIG_RENDERER_OPENGL >= 43, true  },
		{ "GL_ARB_depth_clamp",                    BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_ARB_ES3_compatibility",              BGFX_CONFIG_RENDERER_OPENGL >= 43, true  },
		{ "GL_ARB_framebuffer_sRGB",               false,                             true  },
		{ "GL_ARB_get_program_binary",             BGFX_CONFIG_RENDERER_OPENGL >= 41, true  },
		{ "GL_ARB_half_float_vertex",              false,                             true  },
		{ "GL_ARB_instanced_arrays",               BGFX_CONFIG_RENDERER_OPENGL >= 33, true  },
		{ "GL_ARB_multisample",                    false,                             true  },
		{ "GL_ARB_sampler_objects",                BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_ARB_seamless_cube_map",              BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_ARB_texture_float",                  BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_ARB_texture_multisample",            false,                             true  },
		{ "GL_ARB_texture_swizzle",                BGFX_CONFIG_RENDERER_OPENGL >= 33, true  },
		{ "GL_ARB_timer_query",                    false,                             true  },
		{ "GL_ARB_vertex_array_object",            BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_ARB_vertex_type_2_10_10_10_rev",     false,                             true  },
		{ "GL_ATI_meminfo",                        false,                             true  },
		{ "GL_CHROMIUM_framebuffer_multisample",   false,                             true  },
		{ "GL_CHROMIUM_texture_compression_dxt3",  false,                             true  },
		{ "GL_CHROMIUM_texture_compression_dxt5",  false,                             true  },
		{ "GL_EXT_bgra",                           false,                             true  },
		{ "GL_EXT_blend_color",                    BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_EXT_blend_minmax",                   BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_EXT_blend_subtract",                 BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_EXT_framebuffer_blit",               BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_EXT_framebuffer_sRGB",               false,                             true  },
		{ "GL_EXT_occlusion_query_boolean",        false,                             true  },
		{ "GL_EXT_texture_compression_dxt1",       false,                             true  },
		{ "GL_EXT_texture_compression_latc",       false,                             true  },
		{ "GL_EXT_texture_compression_rgtc",       BGFX_CONFIG_RENDERER_OPENGL >= 31, true  },
		{ "GL_EXT_texture_compression_s3tc",       false,                             true  },
		{ "GL_EXT_texture_filter_anisotropic",     false,                             true  },
		{ "GL_EXT_texture_format_BGRA8888",        false,                             true  },
		{ "GL_EXT_texture_sRGB",                   false,                             true  },
		{ "GL_EXT_texture_storage",                false,                             true  },
		{ "GL_EXT_texture_swizzle",                false,                             true  },
		{ "GL_EXT_texture_type_2_10_10_10_REV",    false,                             true  },
		{ "GL_EXT_timer_query",                    false,                             true  },
		{ "GL_IMG_multisampled_render_to_texture", false,                             true  },
		{ "GL_IMG_read_format",                    false,                             true  },
		{ "GL_IMG_shader_binary",                  false,                             true  },
		{ "GL_IMG_texture_compression_pvrtc",      false,                             true  },
		{ "GL_IMG_texture_compression_pvrtc2",     false,                             true  },
		{ "GL_IMG_texture_format_BGRA8888",        false,                             true  },
		{ "GL_NVX_gpu_memory_info",                false,                             true  },
		{ "GL_OES_compressed_ETC1_RGB8_texture",   false,                             true  },
		{ "GL_OES_depth_texture",                  false,                             true  },
		{ "GL_OES_get_program_binary",             false,                             true  },
		{ "GL_OES_read_format",                    false,                             true  },
		{ "GL_OES_rgb8_rgba8",                     false,                             true  },
		{ "GL_OES_standard_derivatives",           false,                             true  },
		{ "GL_OES_texture_float",                  false,                             true  },
		{ "GL_OES_texture_float_linear",           false,                             true  },
		{ "GL_OES_texture_half_float",             false,                             true  },
		{ "GL_OES_texture_half_float_linear",      false,                             true  },
		{ "GL_OES_vertex_array_object",            false,                             !BX_PLATFORM_IOS },
		{ "GL_OES_vertex_half_float",              false,                             true  },
		{ "GL_OES_vertex_type_10_10_10_2",         false,                             true  },
	};

#if BGFX_CONFIG_RENDERER_OPENGLES3
#	define s_vertexAttribDivisor glVertexAttribDivisor
#	define s_drawArraysInstanced glDrawArraysInstanced
#	define s_drawElementsInstanced glDrawElementsInstanced
#else
	static void GL_APIENTRY stubVertexAttribDivisor(GLuint /*_index*/, GLuint /*_divisor*/)
	{
	}

	static void GL_APIENTRY stubDrawArraysInstanced(GLenum _mode, GLint _first, GLsizei _count, GLsizei /*_primcount*/)
	{
		GL_CHECK(glDrawArrays(_mode, _first, _count) );
	}

	static void GL_APIENTRY stubDrawElementsInstanced(GLenum _mode, GLsizei _count, GLenum _type, const GLvoid* _indices, GLsizei /*_primcount*/)
	{
		GL_CHECK(glDrawElements(_mode, _count, _type, _indices) );
	}

	static PFNGLVERTEXATTRIBDIVISORBGFXPROC s_vertexAttribDivisor = stubVertexAttribDivisor;
	static PFNGLDRAWARRAYSINSTANCEDBGFXPROC s_drawArraysInstanced = stubDrawArraysInstanced;
	static PFNGLDRAWELEMENTSINSTANCEDBGFXPROC s_drawElementsInstanced = stubDrawElementsInstanced;
#endif // BGFX_CONFIG_RENDERER_OPENGLES3

#if BGFX_CONFIG_DEBUG_GREMEDY
	static void GL_APIENTRY stubStringMarkerGREMEDY(GLsizei /*_len*/, const GLvoid* /*_string*/)
	{
	}

	static void GL_APIENTRY stubFrameTerminatorGREMEDY()
	{
	}
#endif // BGFX_CONFIG_DEBUG_GREMEDY

#if BX_PLATFORM_IOS
	PFNGLBINDVERTEXARRAYOESPROC         glBindVertexArrayOES    = NULL;
	PFNGLDELETEVERTEXARRAYSOESPROC      glDeleteVertexArraysOES = NULL;
	PFNGLGENVERTEXARRAYSOESPROC         glGenVertexArraysOES    = NULL;
	PFNGLPROGRAMBINARYOESPROC           glProgramBinaryOES      = NULL;
	PFNGLGETPROGRAMBINARYOESPROC        glGetProgramBinaryOES   = NULL;
	PFLGLDRAWARRAYSINSTANCEDANGLEPROC   glDrawArraysInstanced   = NULL;
	PFLGLDRAWELEMENTSINSTANCEDANGLEPROC glDrawElementsInstanced = NULL;
#endif // BX_PLATFORM_IOS

	typedef void (*PostSwapBuffersFn)(uint32_t _width, uint32_t _height);

	static const char* getGLString(GLenum _name)
	{
		const char* str = (const char*)glGetString(_name);
		glGetError(); // ignore error if glGetString returns NULL.
		if (NULL != str)
		{
			return str;
		}

		return "<unknown>";
	}

	static uint32_t getGLStringHash(GLenum _name)
	{
		const char* str = (const char*)glGetString(_name);
		glGetError(); // ignore error if glGetString returns NULL.
		if (NULL != str)
		{
			return bx::hashMurmur2A(str, (uint32_t)strlen(str) );
		}

		return 0;
	}

	void dumpExtensions(const char* _extensions)
	{
		if (NULL != _extensions)
		{
			char name[1024];
			const char* pos = _extensions;
			const char* end = _extensions + strlen(_extensions);
			while (pos < end)
			{
				uint32_t len;
				const char* space = strchr(pos, ' ');
				if (NULL != space)
				{
					len = bx::uint32_min(sizeof(name), (uint32_t)(space - pos) );
				}
				else
				{
					len = bx::uint32_min(sizeof(name), (uint32_t)strlen(pos) );
				}

				strncpy(name, pos, len);
				name[len] = '\0';

				BX_TRACE("\t%s", name);

				pos += len+1;
			}
		}
	}

#if BGFX_CONFIG_RENDERER_OPENGL
	const char* toString(GLenum _enum)
	{
		switch (_enum)
		{
		case GL_DEBUG_SOURCE_API_ARB:               return "API";
		case GL_DEBUG_SOURCE_WINDOW_SYSTEM_ARB:     return "WinSys";
		case GL_DEBUG_SOURCE_SHADER_COMPILER_ARB:   return "Shader";
		case GL_DEBUG_SOURCE_THIRD_PARTY_ARB:       return "3rdparty";
		case GL_DEBUG_SOURCE_APPLICATION_ARB:       return "Application";
		case GL_DEBUG_SOURCE_OTHER_ARB:             return "Other";
		case GL_DEBUG_TYPE_ERROR_ARB:               return "Error";
		case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR_ARB: return "Deprecated behavior";
		case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR_ARB:  return "Undefined behavior";
		case GL_DEBUG_TYPE_PORTABILITY_ARB:         return "Portability";
		case GL_DEBUG_TYPE_PERFORMANCE_ARB:         return "Performance";
		case GL_DEBUG_TYPE_OTHER_ARB:               return "Other";
		case GL_DEBUG_SEVERITY_HIGH_ARB:            return "High";
		case GL_DEBUG_SEVERITY_MEDIUM_ARB:          return "Medium";
		case GL_DEBUG_SEVERITY_LOW_ARB:             return "Low";
		default:
			break;
		}

		return "<unknown>";
	}

	static void APIENTRY debugProcCb(GLenum _source, GLenum _type, GLuint _id, GLenum _severity, GLsizei /*_length*/, const GLchar* _message, GLvoid* /*_userParam*/)
	{
		BX_TRACE("src %s, type %s, id %d, severity %s, '%s'"
				, toString(_source)
				, toString(_type)
				, _id
				, toString(_severity)
				, _message
				);
		BX_UNUSED(_source, _type, _id, _severity, _message);
	}
#endif // BGFX_CONFIG_RENDERER_OPENGL

	struct RendererContext
	{
		RendererContext()
			: m_rtMsaa(false)
			, m_capture(NULL)
			, m_captureSize(0)
			, m_maxAnisotropy(0.0f)
			, m_maxMsaa(0)
			, m_vao(0)
			, m_vaoSupport(BGFX_CONFIG_RENDERER_OPENGL >= 31)
			, m_programBinarySupport(false)
			, m_textureSwizzleSupport(false)
			, m_useClearQuad(true)
			, m_flip(false)
			, m_hash( (BX_PLATFORM_WINDOWS<<1) | BX_ARCH_64BIT)
			, m_backBufferFbo(0)
			, m_msaaBackBufferFbo(0)
		{
			m_rt.idx = invalidHandle;
			memset(&m_resolution, 0, sizeof(m_resolution) );
		}

		void updateResolution(const Resolution& _resolution)
		{
			if (m_resolution.m_width != _resolution.m_width
			||  m_resolution.m_height != _resolution.m_height
			||  m_resolution.m_flags != _resolution.m_flags)
			{
				m_textVideoMem.resize(false, _resolution.m_width, _resolution.m_height);
				m_textVideoMem.clear();

				m_resolution = _resolution;

				uint32_t msaa = 1<<( (m_resolution.m_flags&BGFX_RESET_MSAA_MASK)>>BGFX_RESET_MSAA_SHIFT);
				msaa = bx::uint32_min(m_maxMsaa, msaa == 0 ? 0 : 1<<msaa);
				bool vsync = !!(m_resolution.m_flags&BGFX_RESET_VSYNC);
				setRenderContextSize(_resolution.m_width, _resolution.m_height, msaa, vsync);
				updateCapture();
			}
		}

		uint32_t setRenderTarget(RenderTargetHandle _rt, uint32_t _height, bool _msaa = true)
		{
			if (isValid(m_rt)
			&&  m_rt.idx != _rt.idx
			&&  m_rtMsaa)
			{
				RenderTarget& renderTarget = m_renderTargets[m_rt.idx];
				if (0 != renderTarget.m_fbo[1])
				{
					renderTarget.resolve();
				}
			}

			if (!isValid(_rt) )
			{
				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_msaaBackBufferFbo) );
			}
			else
			{
				RenderTarget& renderTarget = m_renderTargets[_rt.idx];
				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, renderTarget.m_fbo[0]) );
				_height = renderTarget.m_height;
			}

			m_rt = _rt;
			m_rtMsaa = _msaa;

			return _height;
		}

		void createMsaaFbo(uint32_t _width, uint32_t _height, uint32_t _msaa)
		{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
			if (1 < _msaa)
			{
				GL_CHECK(glGenFramebuffers(1, &m_msaaBackBufferFbo) );
				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_msaaBackBufferFbo) );
				GL_CHECK(glGenRenderbuffers(BX_COUNTOF(m_msaaBackBufferRbos), m_msaaBackBufferRbos) );
				GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, m_msaaBackBufferRbos[0]) );
				GL_CHECK(glRenderbufferStorageMultisample(GL_RENDERBUFFER, _msaa, GL_RGBA8, _width, _height) );
				GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, m_msaaBackBufferRbos[1]) );
				GL_CHECK(glRenderbufferStorageMultisample(GL_RENDERBUFFER, _msaa, GL_DEPTH24_STENCIL8, _width, _height) );
				GL_CHECK(glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, m_msaaBackBufferRbos[0]) );
				GL_CHECK(glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, m_msaaBackBufferRbos[1]) );

				BX_CHECK(GL_FRAMEBUFFER_COMPLETE ==  glCheckFramebufferStatus(GL_FRAMEBUFFER)
					, "glCheckFramebufferStatus failed 0x%08x"
					, glCheckFramebufferStatus(GL_FRAMEBUFFER)
					);

				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_msaaBackBufferFbo) );
			}
#else
			BX_UNUSED(_width, _height, _msaa);
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		}

		void destroyMsaaFbo()
		{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
			if (0 != m_msaaBackBufferFbo)
			{
				GL_CHECK(glDeleteFramebuffers(1, &m_msaaBackBufferFbo) );
				GL_CHECK(glDeleteRenderbuffers(BX_COUNTOF(m_msaaBackBufferRbos), m_msaaBackBufferRbos) );
				m_msaaBackBufferFbo = 0;
			}
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		}

		void blitMsaaFbo()
		{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
			if (0 != m_msaaBackBufferFbo)
			{
				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_backBufferFbo) );
				GL_CHECK(glBindFramebuffer(GL_READ_FRAMEBUFFER, m_msaaBackBufferFbo) );
				GL_CHECK(glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0) );
				uint32_t width = m_resolution.m_width;
				uint32_t height = m_resolution.m_height;
				GL_CHECK(glBlitFramebuffer(0
					, 0
					, width
					, height
					, 0
					, 0
					, width
					, height
					, GL_COLOR_BUFFER_BIT
					, GL_LINEAR
					) );
				GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_backBufferFbo) );
			}
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		}

		void setRenderContextSize(uint32_t _width, uint32_t _height, uint32_t _msaa = 0, bool _vsync = false)
		{
			if (_width != 0
			||  _height != 0)
			{
				if (!m_glctx.isValid() )
				{
					m_glctx.create(_width, _height);
#if BX_PLATFORM_IOS
					// BK - Temp, need to figure out how to deal with FBO created by context.
					m_backBufferFbo = m_glctx.m_fbo;
					m_msaaBackBufferFbo = m_glctx.m_fbo;
#endif // BX_PLATFORM_IOS
				}
				else
				{
					destroyMsaaFbo();

					m_glctx.resize(_width, _height, _vsync);

					createMsaaFbo(_width, _height, _msaa);
				}
			}

			m_flip = true;
		}

		void flip()
		{
			if (m_flip)
			{
				m_glctx.swap();
			}
		}

		void invalidateCache()
		{
			if (m_vaoSupport)
			{
				m_vaoStateCache.invalidate();
			}

#if !BGFX_CONFIG_RENDERER_OPENGLES2
			if (m_samplerObjectSupport)
			{
				m_samplerStateCache.invalidate();
			}
#endif // !BGFX_CONFIG_RENDERER_OPENGLES2
		}

		void setSamplerState(uint32_t _stage, uint32_t _numMips, uint32_t _flags)
		{
#if BGFX_CONFIG_RENDERER_OPENGLES2
			BX_UNUSED(_stage, _numMips, _flags);
#else
			if (0 == (BGFX_SAMPLER_DEFAULT_FLAGS & _flags) )
			{
				GLuint sampler = m_samplerStateCache.find(_flags);

				if (UINT32_MAX == sampler)
				{
					sampler = m_samplerStateCache.add(_flags);

					GL_CHECK(glSamplerParameteri(sampler, GL_TEXTURE_WRAP_S, s_textureAddress[(_flags&BGFX_TEXTURE_U_MASK)>>BGFX_TEXTURE_U_SHIFT]) );
					GL_CHECK(glSamplerParameteri(sampler, GL_TEXTURE_WRAP_T, s_textureAddress[(_flags&BGFX_TEXTURE_V_MASK)>>BGFX_TEXTURE_V_SHIFT]) );
					GL_CHECK(glSamplerParameteri(sampler, GL_TEXTURE_WRAP_R, s_textureAddress[(_flags&BGFX_TEXTURE_W_MASK)>>BGFX_TEXTURE_W_SHIFT]) );

					uint32_t mag = (_flags&BGFX_TEXTURE_MAG_MASK)>>BGFX_TEXTURE_MAG_SHIFT;
					uint32_t min = (_flags&BGFX_TEXTURE_MIN_MASK)>>BGFX_TEXTURE_MIN_SHIFT;
					uint32_t mip = (_flags&BGFX_TEXTURE_MIP_MASK)>>BGFX_TEXTURE_MIP_SHIFT;
					GLenum minFilter = s_textureFilterMin[min][1 < _numMips ? mip+1 : 0];
					GL_CHECK(glSamplerParameteri(sampler, GL_TEXTURE_MAG_FILTER, s_textureFilterMag[mag]) );
					GL_CHECK(glSamplerParameteri(sampler, GL_TEXTURE_MIN_FILTER, minFilter) );
					if (0 != (_flags & (BGFX_TEXTURE_MIN_ANISOTROPIC|BGFX_TEXTURE_MAG_ANISOTROPIC) ) 
					&&  0.0f < m_maxAnisotropy)
					{
						GL_CHECK(glSamplerParameterf(sampler, GL_TEXTURE_MAX_ANISOTROPY_EXT, m_maxAnisotropy) );
					}
				}

				GL_CHECK(glBindSampler(_stage, sampler) );
			}
			else
			{
				GL_CHECK(glBindSampler(_stage, 0) );
			}
#endif // BGFX_CONFIG_RENDERER_OPENGLES2
		}

		void updateCapture()
		{
			if (m_resolution.m_flags&BGFX_RESET_CAPTURE)
			{
				m_captureSize = m_resolution.m_width*m_resolution.m_height*4;
				m_capture = BX_REALLOC(g_allocator, m_capture, m_captureSize);
				g_callback->captureBegin(m_resolution.m_width, m_resolution.m_height, m_resolution.m_width*4, TextureFormat::BGRA8, true);
			}
			else
			{
				captureFinish();
			}
		}

		void capture()
		{
			if (NULL != m_capture)
			{
				GL_CHECK(glReadPixels(0
					, 0
					, m_resolution.m_width
					, m_resolution.m_height
					, m_readPixelsFmt
					, GL_UNSIGNED_BYTE
					, m_capture
					) );

				g_callback->captureFrame(m_capture, m_captureSize);
			}
		}

		void captureFinish()
		{
			if (NULL != m_capture)
			{
				g_callback->captureEnd();
				BX_FREE(g_allocator, m_capture);
				m_capture = NULL;
				m_captureSize = 0;
			}
		}

		void saveScreenShot(const char* _filePath)
		{
			uint32_t length = m_resolution.m_width*m_resolution.m_height*4;
			uint8_t* data = (uint8_t*)BX_ALLOC(g_allocator, length);

			uint32_t width = m_resolution.m_width;
			uint32_t height = m_resolution.m_height;

			GL_CHECK(glReadPixels(0
				, 0
				, width
				, height
				, m_readPixelsFmt
				, GL_UNSIGNED_BYTE
				, data
				) );

			if (GL_RGBA == m_readPixelsFmt)
			{
				imageSwizzleBgra8(width, height, data, data);
			}

			g_callback->screenShot(_filePath
				, width
				, height
				, width*4
				, data
				, length
				, true
				);
			BX_FREE(g_allocator, data);
		}

		void init()
		{
			setRenderContextSize(BGFX_DEFAULT_WIDTH, BGFX_DEFAULT_HEIGHT);

			m_vendor = getGLString(GL_VENDOR);
			m_renderer = getGLString(GL_RENDERER);
			m_version = getGLString(GL_VERSION);
			m_glslVersion = getGLString(GL_SHADING_LANGUAGE_VERSION);

#if BGFX_CONFIG_DEBUG_GREMEDY
			if (NULL == glStringMarkerGREMEDY
			||  NULL == glFrameTerminatorGREMEDY)
			{
				glStringMarkerGREMEDY = stubStringMarkerGREMEDY;
				glFrameTerminatorGREMEDY = stubFrameTerminatorGREMEDY;
			}
#endif // BGFX_CONFIG_DEBUG_GREMEDY

#if BGFX_CONFIG_RENDERER_OPENGL
			m_queries.create();
#endif // BGFX_CONFIG_RENDERER_OPENGL
		}

		void shutdown()
		{
			captureFinish();

			invalidateCache();

#if BGFX_CONFIG_RENDERER_OPENGL
			m_queries.destroy();
#endif // BGFX_CONFIG_RENDERER_OPENGL

			destroyMsaaFbo();
			m_glctx.destroy();

			m_flip = false;
		}

		IndexBuffer m_indexBuffers[BGFX_CONFIG_MAX_INDEX_BUFFERS];
		VertexBuffer m_vertexBuffers[BGFX_CONFIG_MAX_VERTEX_BUFFERS];
		Shader m_vertexShaders[BGFX_CONFIG_MAX_VERTEX_SHADERS];
		Shader m_fragmentShaders[BGFX_CONFIG_MAX_FRAGMENT_SHADERS];
		Program m_program[BGFX_CONFIG_MAX_PROGRAMS];
		Texture m_textures[BGFX_CONFIG_MAX_TEXTURES];
		VertexDecl m_vertexDecls[BGFX_CONFIG_MAX_VERTEX_DECLS];
		RenderTarget m_renderTargets[BGFX_CONFIG_MAX_RENDER_TARGETS];
		UniformRegistry m_uniformReg;
		void* m_uniforms[BGFX_CONFIG_MAX_UNIFORMS];
#if BGFX_CONFIG_RENDERER_OPENGL
		Queries m_queries;
#endif // BGFX_CONFIG_RENDERER_OPENGL

		VaoStateCache m_vaoStateCache;
#if !BGFX_CONFIG_RENDERER_OPENGLES2
		SamplerStateCache m_samplerStateCache;
#endif // !BGFX_CONFIG_RENDERER_OPENGLES2

		TextVideoMem m_textVideoMem;
		RenderTargetHandle m_rt;
		bool m_rtMsaa;

		Resolution m_resolution;
		void* m_capture;
		uint32_t m_captureSize;
		float m_maxAnisotropy;
		int32_t m_maxMsaa;
		GLuint m_vao;
		bool m_vaoSupport;
		bool m_samplerObjectSupport;
		bool m_programBinarySupport;
		bool m_textureSwizzleSupport;
		bool m_useClearQuad;
		bool m_flip;

		uint64_t m_hash;

		GLenum m_readPixelsFmt;
		GLuint m_backBufferFbo;
		GLuint m_msaaBackBufferFbo;
		GLuint m_msaaBackBufferRbos[2];
		GlContext m_glctx;

		const char* m_vendor;
		const char* m_renderer;
		const char* m_version;
		const char* m_glslVersion;
	};

	RendererContext* s_renderCtx;

	const char* glslTypeName(GLuint _type)
	{
#define GLSL_TYPE(_ty) case _ty: return #_ty

		switch (_type)
		{
			GLSL_TYPE(GL_FLOAT);
			GLSL_TYPE(GL_FLOAT_VEC2);
			GLSL_TYPE(GL_FLOAT_VEC3);
			GLSL_TYPE(GL_FLOAT_VEC4);
			GLSL_TYPE(GL_FLOAT_MAT2);
			GLSL_TYPE(GL_FLOAT_MAT3);
			GLSL_TYPE(GL_FLOAT_MAT4);
// 			GLSL_TYPE(GL_FLOAT_MAT2x3);
// 			GLSL_TYPE(GL_FLOAT_MAT2x4);
// 			GLSL_TYPE(GL_FLOAT_MAT3x2);
// 			GLSL_TYPE(GL_FLOAT_MAT3x4);
// 			GLSL_TYPE(GL_FLOAT_MAT4x2);
// 			GLSL_TYPE(GL_FLOAT_MAT4x3);
// 			GLSL_TYPE(GL_SAMPLER_1D);
 			GLSL_TYPE(GL_SAMPLER_2D);
			GLSL_TYPE(GL_SAMPLER_3D);
			GLSL_TYPE(GL_SAMPLER_CUBE);
// 			GLSL_TYPE(GL_SAMPLER_1D_SHADOW);
// 			GLSL_TYPE(GL_SAMPLER_2D_SHADOW);
		}

#undef GLSL_TYPE

		return "UNKNOWN GLSL TYPE!";
	}

	const char* glEnumName(GLenum _enum)
	{
#define GLENUM(_ty) case _ty: return #_ty

		switch (_enum)
		{
			GLENUM(GL_TEXTURE);
			GLENUM(GL_RENDERBUFFER);
		}

#undef GLENUM

		return "UNKNOWN GLENUM!";
	}

	UniformType::Enum convertGlType(GLenum _type)
	{
		switch (_type)
		{
		case GL_FLOAT:
			return UniformType::Uniform1fv;

		case GL_FLOAT_VEC2:
			return UniformType::Uniform2fv;

		case GL_FLOAT_VEC3:
			return UniformType::Uniform3fv;

		case GL_FLOAT_VEC4:
			return UniformType::Uniform4fv;

		case GL_FLOAT_MAT2:
			break;

		case GL_FLOAT_MAT3:
			return UniformType::Uniform3x3fv;

		case GL_FLOAT_MAT4:
			return UniformType::Uniform4x4fv;

// 		case GL_FLOAT_MAT2x3:
// 		case GL_FLOAT_MAT2x4:
// 		case GL_FLOAT_MAT3x2:
// 		case GL_FLOAT_MAT3x4:
// 		case GL_FLOAT_MAT4x2:
// 		case GL_FLOAT_MAT4x3:
// 			break;

// 		case GL_SAMPLER_1D:
		case GL_SAMPLER_2D:
		case GL_SAMPLER_3D:
		case GL_SAMPLER_CUBE:
// 		case GL_SAMPLER_1D_SHADOW:
// 		case GL_SAMPLER_2D_SHADOW:
			return UniformType::Uniform1iv;
		};

		return UniformType::End;
	}

	void Program::create(const Shader& _vsh, const Shader& _fsh)
	{
		m_id = glCreateProgram();
		BX_TRACE("program create: %d: %d, %d", m_id, _vsh.m_id, _fsh.m_id);

		bool cached = false;

		uint64_t id = (uint64_t(_vsh.m_hash)<<32) | _fsh.m_hash;
		id ^= s_renderCtx->m_hash;

		if (s_renderCtx->m_programBinarySupport)
		{
			uint32_t length = g_callback->cacheReadSize(id);
			cached = length > 0;

			if (cached)
			{
				void* data = BX_ALLOC(g_allocator, length);
				if (g_callback->cacheRead(id, data, length) )
				{
					bx::MemoryReader reader(data, length);

					GLenum format;
					bx::read(&reader, format);

					GL_CHECK(glProgramBinary(m_id, format, reader.getDataPtr(), (GLsizei)reader.remaining() ) );
				}

				BX_FREE(g_allocator, data);
			}

#if BGFX_CONFIG_RENDERER_OPENGL
			GL_CHECK(glProgramParameteri(m_id, GL_PROGRAM_BINARY_RETRIEVABLE_HINT, GL_TRUE) );
#endif // BGFX_CONFIG_RENDERER_OPENGL
		}

		if (!cached)
		{
			GL_CHECK(glAttachShader(m_id, _vsh.m_id) );
			GL_CHECK(glAttachShader(m_id, _fsh.m_id) );
			GL_CHECK(glLinkProgram(m_id) );
			GL_CHECK(glDetachShader(m_id, _vsh.m_id) );
			GL_CHECK(glDetachShader(m_id, _fsh.m_id) );

			GLint linked = 0;
			GL_CHECK(glGetProgramiv(m_id, GL_LINK_STATUS, &linked) );

			if (0 == linked)
			{
				char log[1024];
				GL_CHECK(glGetProgramInfoLog(m_id, sizeof(log), NULL, log) );
				BX_TRACE("%d: %s", linked, log);

				GL_CHECK(glDeleteProgram(m_id) );
				return;
			}

			if (s_renderCtx->m_programBinarySupport)
			{
				GLint programLength;
				GLenum format;
				GL_CHECK(glGetProgramiv(m_id, GL_PROGRAM_BINARY_LENGTH, &programLength) );

				if (0 < programLength)
				{
					uint32_t length = programLength + 4;
					uint8_t* data = (uint8_t*)BX_ALLOC(g_allocator, length);
					GL_CHECK(glGetProgramBinary(m_id, programLength, NULL, &format, &data[4]) );
					*(uint32_t*)data = format;

					g_callback->cacheWrite(id, data, length);

					BX_FREE(g_allocator, data);
				}
			}
		}

		init();
	}

	void Program::destroy()
	{
		if (NULL != m_constantBuffer)
		{
			ConstantBuffer::destroy(m_constantBuffer);
			m_constantBuffer = NULL;
		}
		m_numPredefined = 0;

		if (0 != m_id)
		{
			GL_CHECK(glUseProgram(0) );
			GL_CHECK(glDeleteProgram(m_id) );
			m_id = 0;
		}

		m_vcref.invalidate(s_renderCtx->m_vaoStateCache);
	}

	void Program::init()
	{
		GLint activeAttribs;
		GLint activeUniforms;

		GL_CHECK(glGetProgramiv(m_id, GL_ACTIVE_ATTRIBUTES, &activeAttribs) );
		GL_CHECK(glGetProgramiv(m_id, GL_ACTIVE_UNIFORMS, &activeUniforms) );

		GLint max0, max1;
		GL_CHECK(glGetProgramiv(m_id, GL_ACTIVE_ATTRIBUTE_MAX_LENGTH, &max0) );
		GL_CHECK(glGetProgramiv(m_id, GL_ACTIVE_UNIFORM_MAX_LENGTH, &max1) );

		GLint maxLength = bx::uint32_max(max0, max1);
		char* name = (char*)BX_ALLOC(g_allocator, maxLength + 1);

		BX_TRACE("Program %d", m_id);
		BX_TRACE("Attributes:");
		for (int32_t ii = 0; ii < activeAttribs; ++ii)
		{
			GLint size;
			GLenum type;

			GL_CHECK(glGetActiveAttrib(m_id, ii, maxLength + 1, NULL, &size, &type, name) );
			BX_TRACE("\t%s %s is at location %d"
				, glslTypeName(type)
				, name
				, glGetAttribLocation(m_id, name)
				);
		}

		m_numPredefined = 0;
		m_constantBuffer = ConstantBuffer::create(1024);
 		m_numSamplers = 0;

		BX_TRACE("Uniforms:");
		for (int32_t ii = 0; ii < activeUniforms; ++ii)
		{
			GLint num;
			GLenum gltype;

			GL_CHECK(glGetActiveUniform(m_id, ii, maxLength + 1, NULL, &num, &gltype, name) );
			GLint loc = glGetUniformLocation(m_id, name);

			int offset = 0;
			char* array = strchr(name, '[');
			if (NULL != array)
			{
				BX_TRACE("--- %s", name);
				*array = '\0';
				array++;
				char* end = strchr(array, ']');
				*end = '\0';
				offset = atoi(array);
			}

 			if (GL_SAMPLER_2D == gltype)
 			{
 				BX_TRACE("Sampler %d at %d.", m_numSamplers, loc);
 				m_sampler[m_numSamplers] = loc;
 				m_numSamplers++;
 			}

			const void* data = NULL;
			PredefinedUniform::Enum predefined = nameToPredefinedUniformEnum(name);
			if (PredefinedUniform::Count != predefined)
			{
				m_predefined[m_numPredefined].m_loc = loc;
				m_predefined[m_numPredefined].m_type = predefined;
				m_predefined[m_numPredefined].m_count = num;
				m_numPredefined++;
			}
			else
			{
				const UniformInfo* info = s_renderCtx->m_uniformReg.find(name);
				if (NULL != info)
				{
					data = info->m_data;
					UniformType::Enum type = convertGlType(gltype);
					m_constantBuffer->writeUniformRef(type, 0, data, num);
					m_constantBuffer->write(loc);
					BX_TRACE("store %s %p", name, data);
				}
			}

			BX_TRACE("\tuniform %s %s%s is at location %d, size %d (%p), offset %d"
				, glslTypeName(gltype)
				, name
				, PredefinedUniform::Count != predefined ? "*" : ""
				, loc
				, num
				, data
				, offset
				);
			BX_UNUSED(offset);
		}

		m_constantBuffer->finish();

		BX_FREE(g_allocator, name);

		memset(m_attributes, 0xff, sizeof(m_attributes) );
		uint32_t used = 0;
		for (uint32_t ii = 0; ii < Attrib::Count; ++ii)
		{
			GLint loc = glGetAttribLocation(m_id, s_attribName[ii]);
			if (-1 != loc)
			{
				BX_TRACE("attr %s: %d", s_attribName[ii], loc);
				m_attributes[ii] = loc;
				m_used[used++] = ii;
			}
		}
		m_used[used] = Attrib::Count;

		used = 0;
		for (uint32_t ii = 0; ii < BX_COUNTOF(s_instanceDataName); ++ii)
		{
			GLuint loc = glGetAttribLocation(m_id, s_instanceDataName[ii]);
			if (GLuint(-1) != loc )
			{
				BX_TRACE("instance data %s: %d", s_instanceDataName[ii], loc);
				m_instanceData[used++] = loc;
			}
		}
		m_instanceData[used] = 0xffff;
	}

	void Program::bindAttributes(const VertexDecl& _vertexDecl, uint32_t _baseVertex) const
	{
		uint32_t enabled = 0;
		for (uint32_t ii = 0; Attrib::Count != m_used[ii]; ++ii)
		{
			Attrib::Enum attr = Attrib::Enum(m_used[ii]);
			GLint loc = m_attributes[attr];

			uint8_t num;
			AttribType::Enum type;
			bool normalized;
			bool asInt;
			_vertexDecl.decode(attr, num, type, normalized, asInt);

			if (-1 != loc
			&&  0xff != _vertexDecl.m_attributes[attr])
			{
				GL_CHECK(glEnableVertexAttribArray(loc) );
				enabled |= 1<<attr;

				GL_CHECK(s_vertexAttribDivisor(loc, 0) );

				uint32_t baseVertex = _baseVertex*_vertexDecl.m_stride + _vertexDecl.m_offset[attr];
				GL_CHECK(glVertexAttribPointer(loc, num, s_attribType[type], normalized, _vertexDecl.m_stride, (void*)(uintptr_t)baseVertex) );
			}
			else
			{
//				GL_CHECK(glDisableVertexAttribArray(loc) );

				switch (num)
				{
				case 1:
					GL_CHECK(glVertexAttrib1f(loc, 0.0f) );
					break;

				case 2:
					GL_CHECK(glVertexAttrib2f(loc, 0.0f, 0.0f) );
					break;

				case 3:
					GL_CHECK(glVertexAttrib3f(loc, 0.0f, 0.0f, 0.0f) );
					break;

				case 4:
					GL_CHECK(glVertexAttrib4f(loc, 0.0f, 0.0f, 0.0f, 0.0f) );
					break;

				default:
					BX_CHECK(false, "You should not be here!");
					break;
				}
			}
		}
	}

	void Program::bindInstanceData(uint32_t _stride, uint32_t _baseVertex) const
	{
		uint32_t baseVertex = _baseVertex;
		for (uint32_t ii = 0; 0xffff != m_instanceData[ii]; ++ii)
		{
			GLint loc = m_instanceData[ii];
			GL_CHECK(glEnableVertexAttribArray(loc) );
			GL_CHECK(glVertexAttribPointer(loc, 4, GL_FLOAT, GL_FALSE, _stride, (void*)(uintptr_t)baseVertex) );
			GL_CHECK(s_vertexAttribDivisor(loc, 1) );
			baseVertex += 16;
		}
	}

	void IndexBuffer::destroy()
	{
		GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0) );
		GL_CHECK(glDeleteBuffers(1, &m_id) );

		m_vcref.invalidate(s_renderCtx->m_vaoStateCache);
	}

	void VertexBuffer::destroy()
	{
		GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, 0) );
		GL_CHECK(glDeleteBuffers(1, &m_id) );

		m_vcref.invalidate(s_renderCtx->m_vaoStateCache);
	}

	static void texImage(GLenum _target, GLint _level, GLint _internalFormat, GLsizei _width, GLsizei _height, GLsizei _depth, GLint _border, GLenum _format, GLenum _type, const GLvoid* _data)
	{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (_target == GL_TEXTURE_3D)
		{
			GL_CHECK(glTexImage3D(_target, _level, _internalFormat, _width, _height, _depth, _border, _format, _type, _data) );
		}
		else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		{
			BX_UNUSED(_depth);
			GL_CHECK(glTexImage2D(_target, _level, _internalFormat, _width, _height, _border, _format, _type, _data) );
		}
	}

	static void texSubImage(GLenum _target, GLint _level, GLint _xoffset, GLint _yoffset, GLint _zoffset, GLsizei _width, GLsizei _height, GLsizei _depth, GLenum _format, GLenum _type, const GLvoid* _data)
	{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (_target == GL_TEXTURE_3D)
		{
			GL_CHECK(glTexSubImage3D(_target, _level, _xoffset, _yoffset, _zoffset, _width, _height, _depth, _format, _type, _data) );
		}
		else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		{
			BX_UNUSED(_zoffset, _depth);
			GL_CHECK(glTexSubImage2D(_target, _level, _xoffset, _yoffset, _width, _height, _format, _type, _data) );
		}
	}

	static void compressedTexImage(GLenum _target, GLint _level, GLenum _internalformat, GLsizei _width, GLsizei _height, GLsizei _depth, GLint _border, GLsizei _imageSize, const GLvoid* _data)
	{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (_target == GL_TEXTURE_3D)
		{
			GL_CHECK(glCompressedTexImage3D(_target, _level, _internalformat, _width, _height, _depth, _border, _imageSize, _data) );
		}
		else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		{
			BX_UNUSED(_depth);
			GL_CHECK(glCompressedTexImage2D(_target, _level, _internalformat, _width, _height, _border, _imageSize, _data) );
		}
	}

	static void compressedTexSubImage(GLenum _target, GLint _level, GLint _xoffset, GLint _yoffset, GLint _zoffset, GLsizei _width, GLsizei _height, GLsizei _depth, GLenum _format, GLsizei _imageSize, const GLvoid* _data)
	{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (_target == GL_TEXTURE_3D)
		{
			GL_CHECK(glCompressedTexSubImage3D(_target, _level, _xoffset, _yoffset, _zoffset, _width, _height, _depth, _format, _imageSize, _data) );
		}
		else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		{
			BX_UNUSED(_zoffset, _depth);
			GL_CHECK(glCompressedTexSubImage2D(_target, _level, _xoffset, _yoffset, _width, _height, _format, _imageSize, _data) );
		}
	}

	void Texture::init(GLenum _target, uint8_t _format, uint8_t _numMips, uint32_t _flags)
	{
		m_target = _target;
		m_numMips = _numMips;
		m_flags = _flags;
		m_currentFlags = UINT32_MAX;
		m_requestedFormat = _format;
		m_textureFormat   = _format;

		GL_CHECK(glGenTextures(1, &m_id) );
		BX_CHECK(0 != m_id, "Failed to generate texture id.");
		GL_CHECK(glBindTexture(_target, m_id) );

		setSamplerState(_flags);

		const TextureFormatInfo& tfi = s_textureFormat[_format];
		m_fmt = tfi.m_fmt;
		m_type = tfi.m_type;

		const bool compressed = TextureFormat::Unknown > _format;
		const bool decompress = !tfi.m_supported && compressed;

		if (decompress)
		{
			m_textureFormat = (uint8_t)TextureFormat::BGRA8;
			const TextureFormatInfo& tfi = s_textureFormat[TextureFormat::BGRA8];
			m_fmt = tfi.m_fmt;
			m_type = tfi.m_type;
		}

#if BGFX_CONFIG_RENDERER_OPENGL
		if (GL_RGBA == m_fmt
		&&  s_renderCtx->m_textureSwizzleSupport)
		{
			GLint swizzleMask[] = { GL_BLUE, GL_GREEN, GL_RED, GL_ALPHA };
			GL_CHECK(glTexParameteriv(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_RGBA, swizzleMask) );
		}
#endif // BGFX_CONFIG_RENDERER_OPENGL
	}

	void Texture::create(const Memory* _mem, uint32_t _flags)
	{
		ImageContainer imageContainer;

		if (imageParse(imageContainer, _mem->data, _mem->size) )
		{
			uint8_t numMips = imageContainer.m_numMips;

			GLenum target = GL_TEXTURE_2D;
			if (imageContainer.m_cubeMap)
			{
				target = GL_TEXTURE_CUBE_MAP;
			}
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
			else if (imageContainer.m_depth > 1)
			{
				target = GL_TEXTURE_3D;
			}
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3

			init(target
				, imageContainer.m_format
				, numMips
				, _flags
				);

			target = GL_TEXTURE_CUBE_MAP == m_target ? GL_TEXTURE_CUBE_MAP_POSITIVE_X : m_target;

			const GLenum internalFmt = s_textureFormat[m_textureFormat].m_internalFmt;

			const bool swizzle    = GL_RGBA == internalFmt && !s_renderCtx->m_textureSwizzleSupport;
			const bool convert    = m_textureFormat != m_requestedFormat;
			const bool compressed = TextureFormat::Unknown > m_textureFormat;
			const uint32_t min    = convert && compressed ? 4 : 1;

			uint8_t* temp = NULL;
			if (convert || swizzle)
			{
				temp = (uint8_t*)BX_ALLOC(g_allocator, imageContainer.m_width*imageContainer.m_height*4);
			}

			for (uint8_t side = 0, numSides = imageContainer.m_cubeMap ? 6 : 1; side < numSides; ++side)
			{
				uint32_t width  = imageContainer.m_width;
				uint32_t height = imageContainer.m_height;
				uint32_t depth  = imageContainer.m_depth;

				for (uint32_t lod = 0, num = numMips; lod < num; ++lod)
				{
					width  = bx::uint32_max(min, width);
					height = bx::uint32_max(min, height);
					depth  = bx::uint32_max(1, depth);

					ImageMip mip;
					if (imageGetRawData(imageContainer, side, lod, _mem->data, _mem->size, mip) )
					{
						if (compressed)
						{
							compressedTexImage(target+side
								, lod
								, internalFmt
								, width
								, height
								, depth
								, 0
								, mip.m_size
								, mip.m_data
								);
						}
						else
						{
							const uint8_t* data = mip.m_data;

							if (convert)
							{
								imageDecodeToBgra8(temp, mip.m_data, mip.m_width, mip.m_height, mip.m_format);
								data = temp;
							}

							if (swizzle)
							{
								imageSwizzleBgra8(width, height, data, temp);
								data = temp;
							}

							texImage(target+side
								, lod
								, internalFmt
								, width
								, height
								, depth
								, 0
								, m_fmt
								, m_type
								, data
								);
						}
					}
					else
					{
						if (compressed)
						{
							uint32_t size = bx::uint32_max(1, (width  + 3)>>2)
										  * bx::uint32_max(1, (height + 3)>>2)
										  * 4*4*getBitsPerPixel(TextureFormat::Enum(m_textureFormat) )/8
										  ;

							compressedTexImage(target+side
								, lod
								, internalFmt
								, width
								, height
								, depth
								, 0
								, size
								, NULL
								);
						}
						else
						{
							texImage(target+side
								, lod
								, internalFmt
								, width
								, height
								, depth
								, 0
								, m_fmt
								, m_type
								, NULL
								);
						}
					}

					width  >>= 1;
					height >>= 1;
					depth  >>= 1;
				}
			}

			if (NULL != temp)
			{
				BX_FREE(g_allocator, temp);
			}
		}

		GL_CHECK(glBindTexture(m_target, 0) );
	}

	void Texture::createColor(uint32_t _colorFormat, uint32_t _width, uint32_t _height, GLenum _min, GLenum _mag)
	{
		const RenderTargetColorFormat& rtcf = s_colorFormat[_colorFormat];
		GLenum internalFormat = rtcf.m_internalFmt;
		GLenum type = rtcf.m_type;
		m_target = GL_TEXTURE_2D;
		m_numMips = 1;
//		m_flags = _flags;
		m_currentFlags = UINT32_MAX;

		GL_CHECK(glGenTextures(1, &m_id) );
		BX_CHECK(0 != m_id, "Failed to generate texture id.");
		GL_CHECK(glBindTexture(m_target, m_id) );

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MAX_LEVEL, 0) );
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3

		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MIN_FILTER, _min) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MAG_FILTER, _mag) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE) );

		GL_CHECK(glTexImage2D(m_target
			, 0
			, internalFormat
			, _width
			, _height
			, 0
			, GL_RGBA
			, type
			, NULL
			) );

		GL_CHECK(glBindTexture(m_target, 0) );
	}

	void Texture::createDepth(uint32_t _width, uint32_t _height)
	{
		m_target = GL_TEXTURE_2D;
		m_numMips = 1;

		GL_CHECK(glGenTextures(1, &m_id) );
		BX_CHECK(0 != m_id, "Failed to generate texture id.");
		GL_CHECK(glBindTexture(m_target, m_id) );

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MAX_LEVEL, 0) );
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3

//		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_COMPARE_MODE, GL_NONE) );
//		GL_CHECK(glTexParameteri(m_target, GL_DEPTH_TEXTURE_MODE, GL_NONE) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MIN_FILTER, GL_LINEAR) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_MAG_FILTER, GL_LINEAR) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE) );
		GL_CHECK(glTexParameteri(m_target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE) );

		// OpenGL ES 2.0 doesn't support GL_DEPTH_COMPONENT... this will fail.
		GL_CHECK(glTexImage2D(m_target
							, 0
							, GL_DEPTH_COMPONENT
							, _width
							, _height
							, 0
							, GL_DEPTH_COMPONENT
							, GL_FLOAT
							, NULL
							) );

		GL_CHECK(glBindTexture(m_target, 0) );
	}

	void Texture::destroy()
	{
		if (0 != m_id)
		{
			GL_CHECK(glBindTexture(m_target, 0) );
			GL_CHECK(glDeleteTextures(1, &m_id) );
			m_id = 0;
		}
	}

	void Texture::update(uint8_t _side, uint8_t _mip, const Rect& _rect, uint16_t _z, uint16_t _depth, const Memory* _mem)
	{
		BX_UNUSED(_z, _depth);

		GL_CHECK(glBindTexture(m_target, m_id) );
		GL_CHECK(glPixelStorei(GL_UNPACK_ALIGNMENT, 1) );

		GLenum target = GL_TEXTURE_CUBE_MAP == m_target ? GL_TEXTURE_CUBE_MAP_POSITIVE_X : m_target;

		const bool swizzle    = GL_RGBA == m_fmt && !s_renderCtx->m_textureSwizzleSupport;
		const bool convert    = m_textureFormat != m_requestedFormat;
		const bool compressed = TextureFormat::Unknown > m_textureFormat;

		uint32_t width  = _rect.m_width;
		uint32_t height = _rect.m_height;

		uint8_t* temp = NULL;
		if (convert || swizzle)
		{
			temp = (uint8_t*)BX_ALLOC(g_allocator, width*height*4);
		}

		if (compressed)
		{
			GL_CHECK(compressedTexSubImage(target+_side
				, _mip
				, _rect.m_x
				, _rect.m_y
				, _z
				, _rect.m_width
				, _rect.m_height
				, _depth
				, m_fmt
				, _mem->size
				, _mem->data
				) );
		}
		else
		{
			const uint8_t* data = _mem->data;

			if (convert)
			{
				imageDecodeToBgra8(temp, data, width, height, m_requestedFormat);
				data = temp;
			}

			if (swizzle)
			{
				imageSwizzleBgra8(width, height, data, temp);
				data = temp;
			}

			GL_CHECK(texSubImage(target+_side
				, _mip
				, _rect.m_x
				, _rect.m_y
				, _z
				, _rect.m_width
				, _rect.m_height
				, _depth
				, m_fmt
				, m_type
				, data
				) );
		}

		if (NULL != temp)
		{
			BX_FREE(g_allocator, temp);
		}
	}

	void Texture::setSamplerState(uint32_t _flags)
	{
		const uint32_t flags = _flags&(~BGFX_TEXTURE_RESERVED_MASK);
		if ( (0 != (BGFX_SAMPLER_DEFAULT_FLAGS & _flags) && m_flags != m_currentFlags)
		||  m_currentFlags != flags)
		{
			const GLenum target = m_target;
			const uint8_t numMips = m_numMips;

			GL_CHECK(glTexParameteri(target, GL_TEXTURE_WRAP_S, s_textureAddress[(flags&BGFX_TEXTURE_U_MASK)>>BGFX_TEXTURE_U_SHIFT]) );
			GL_CHECK(glTexParameteri(target, GL_TEXTURE_WRAP_T, s_textureAddress[(flags&BGFX_TEXTURE_V_MASK)>>BGFX_TEXTURE_V_SHIFT]) );

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
			GL_CHECK(glTexParameteri(target, GL_TEXTURE_MAX_LEVEL, numMips-1) );

			if (target == GL_TEXTURE_3D)
			{
				GL_CHECK(glTexParameteri(target, GL_TEXTURE_WRAP_R, s_textureAddress[(flags&BGFX_TEXTURE_W_MASK)>>BGFX_TEXTURE_W_SHIFT]) );
			}
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3

			uint32_t mag = (flags&BGFX_TEXTURE_MAG_MASK)>>BGFX_TEXTURE_MAG_SHIFT;
			uint32_t min = (flags&BGFX_TEXTURE_MIN_MASK)>>BGFX_TEXTURE_MIN_SHIFT;
			uint32_t mip = (flags&BGFX_TEXTURE_MIP_MASK)>>BGFX_TEXTURE_MIP_SHIFT;
			GLenum minFilter = s_textureFilterMin[min][1 < numMips ? mip+1 : 0];
			GL_CHECK(glTexParameteri(target, GL_TEXTURE_MAG_FILTER, s_textureFilterMag[mag]) );
			GL_CHECK(glTexParameteri(target, GL_TEXTURE_MIN_FILTER, minFilter) );
			if (0 != (flags & (BGFX_TEXTURE_MIN_ANISOTROPIC|BGFX_TEXTURE_MAG_ANISOTROPIC) ) 
			&&  0.0f < s_renderCtx->m_maxAnisotropy)
			{
				GL_CHECK(glTexParameterf(target, GL_TEXTURE_MAX_ANISOTROPY_EXT, s_renderCtx->m_maxAnisotropy) );
			}

			m_currentFlags = flags;
		}
	}

	void Texture::commit(uint32_t _stage, uint32_t _flags)
	{
		GL_CHECK(glActiveTexture(GL_TEXTURE0+_stage) );
		GL_CHECK(glBindTexture(m_target, m_id) );

#if BGFX_CONFIG_RENDERER_OPENGLES2
		// GLES2 doesn't have support for sampler object.
		setSamplerState(_flags);
#elif BGFX_CONFIG_RENDERER_OPENGL < 31
		// In case that GL 2.1 sampler object is supported via extension.
		if (s_renderCtx->m_samplerObjectSupport)
		{
			s_renderCtx->setSamplerState(_stage, m_numMips, _flags);
		}
		else
		{
			setSamplerState(_flags);
		}
#else
		// Everything else has sampler object.
		s_renderCtx->setSamplerState(_stage, m_numMips, _flags);
#endif // BGFX_CONFIG_RENDERER_*
	}

	void RenderTarget::create(uint16_t _width, uint16_t _height, uint32_t _flags, uint32_t _textureFlags)
	{
		BX_TRACE("Create render target %dx%d 0x%02x", _width, _height, _flags);

		m_width = _width;
		m_height = _height;
		uint32_t msaa = (_flags&BGFX_RENDER_TARGET_MSAA_MASK)>>BGFX_RENDER_TARGET_MSAA_SHIFT;
		m_msaa = bx::uint32_min(s_renderCtx->m_maxMsaa, msaa == 0 ? 0 : 1<<msaa);

		uint32_t colorFormat = (_flags&BGFX_RENDER_TARGET_COLOR_MASK)>>BGFX_RENDER_TARGET_COLOR_SHIFT;
		uint32_t depthFormat = (_flags&BGFX_RENDER_TARGET_DEPTH_MASK)>>BGFX_RENDER_TARGET_DEPTH_SHIFT;
		GLenum minFilter = s_textureFilterMin[(_textureFlags&BGFX_TEXTURE_MIN_MASK)>>BGFX_TEXTURE_MIN_SHIFT][0];
		GLenum magFilter = s_textureFilterMag[(_textureFlags&BGFX_TEXTURE_MAG_MASK)>>BGFX_TEXTURE_MAG_SHIFT];

		if (0 < colorFormat)
		{
			m_color.createColor(colorFormat, _width, _height, minFilter, magFilter);
		}
		
#if 0 // GLES can't create texture with depth texture format...
		if (0 < depthFormat)
		{
			m_depth.createDepth(_width, _height);
		}
#endif //

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (0 < colorFormat
		&&  0 != m_msaa)
		{
			GL_CHECK(glGenFramebuffers(2, m_fbo) );
			GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_fbo[0]) );

			GL_CHECK(glGenRenderbuffers(1, &m_colorRbo) );
			BX_CHECK(0 != m_colorRbo, "Failed to generate color renderbuffer id.");
			GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, m_colorRbo) );
			GL_CHECK(glRenderbufferStorageMultisample(GL_RENDERBUFFER, m_msaa, s_colorFormat[colorFormat].m_internalFmt, _width, _height) );
			GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, 0) );

			GL_CHECK(glFramebufferRenderbuffer(GL_FRAMEBUFFER
				, GL_COLOR_ATTACHMENT0
				, GL_RENDERBUFFER
				, m_colorRbo
				) );
 
			GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_fbo[1]) );
		}
		else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		{
			GL_CHECK(glGenFramebuffers(1, m_fbo) );
			GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_fbo[0]) );
		}

		if (0 < colorFormat)
		{
			GL_CHECK(glFramebufferTexture2D(GL_FRAMEBUFFER
							, GL_COLOR_ATTACHMENT0
							, m_color.m_target
							, m_color.m_id
							, 0
							) );
		}

		BX_CHECK(GL_FRAMEBUFFER_COMPLETE ==  glCheckFramebufferStatus(GL_FRAMEBUFFER)
			, "glCheckFramebufferStatus failed 0x%08x"
			, glCheckFramebufferStatus(GL_FRAMEBUFFER)
			);

		if (0 < depthFormat)
		{
			GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, m_fbo[0]) );

			if (0 < colorFormat)
			{
#if BGFX_CONFIG_RENDERER_OPENGL
				GLenum depthComponent = GL_DEPTH_COMPONENT32;
#else
				GLenum depthComponent = GL_DEPTH_COMPONENT16;
#endif // BGFX_CONFIG_RENDERER_OPENGL

				GL_CHECK(glGenRenderbuffers(1, &m_depthRbo) );
				BX_CHECK(0 != m_depthRbo, "Failed to generate renderbuffer id.");
				GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, m_depthRbo) );

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
				if (0 != m_msaa)
				{
					GL_CHECK(glRenderbufferStorageMultisample(GL_RENDERBUFFER, m_msaa, depthComponent, _width, _height) );
				}
				else
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
				{
					GL_CHECK(glRenderbufferStorage(GL_RENDERBUFFER, depthComponent, _width, _height) );
				}
				GL_CHECK(glBindRenderbuffer(GL_RENDERBUFFER, 0) );

				GL_CHECK(glFramebufferRenderbuffer(GL_FRAMEBUFFER
					, GL_DEPTH_ATTACHMENT
					, GL_RENDERBUFFER
					, m_depthRbo
					) );
			}
			else
			{
				GL_CHECK(glFramebufferTexture2D(GL_FRAMEBUFFER
					, GL_DEPTH_ATTACHMENT
					, m_depth.m_target
					, m_depth.m_id
					, 0
					) );
			}

			BX_CHECK(GL_FRAMEBUFFER_COMPLETE ==  glCheckFramebufferStatus(GL_FRAMEBUFFER)
				, "glCheckFramebufferStatus failed 0x%08x"
				, glCheckFramebufferStatus(GL_FRAMEBUFFER)
				);
		}

		GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, s_renderCtx->m_msaaBackBufferFbo) );
	}

	void RenderTarget::destroy()
	{
		GL_CHECK(glDeleteFramebuffers(0 == m_fbo[1] ? 1 : 2, m_fbo) );
		memset(m_fbo, 0, sizeof(m_fbo) );

		if (0 != m_colorRbo)
		{
			GL_CHECK(glDeleteRenderbuffers(1, &m_colorRbo) );
			m_colorRbo = 0;
		}

		if (0 != m_depthRbo)
		{
			GL_CHECK(glDeleteRenderbuffers(1, &m_depthRbo) );
			m_depthRbo = 0;
		}

		m_color.destroy();
		m_depth.destroy();
	}

	void RenderTarget::resolve()
	{
#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		BX_CHECK(0 != m_fbo[1], "Can resolve without two framebuffers.");

		GL_CHECK(glBindFramebuffer(GL_READ_FRAMEBUFFER, m_fbo[0]) );
		GL_CHECK(glBindFramebuffer(GL_DRAW_FRAMEBUFFER, m_fbo[1]) );
		GL_CHECK(glBlitFramebuffer(0
				, 0
				, m_width
				, m_height
				, 0
				, 0
				, m_width
				, m_height
				, GL_COLOR_BUFFER_BIT
				, GL_LINEAR
				) );
		GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, s_renderCtx->m_msaaBackBufferFbo) );
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
	}

	void ConstantBuffer::commit()
	{
		reset();

		do
		{
			uint32_t opcode = read();

			if (UniformType::End == opcode)
			{
				break;
			}

			UniformType::Enum type;
			uint16_t ignore;
			uint16_t num;
			uint16_t copy;
			decodeOpcode(opcode, type, ignore, num, copy);

			const char* data;
			if (copy)
			{
				data = read(g_uniformTypeSize[type]*num);
			}
			else
			{
				memcpy(&data, read(sizeof(void*) ), sizeof(void*) );
			}

			uint32_t loc = read();

#define CASE_IMPLEMENT_UNIFORM(_uniform, _glsuffix, _dxsuffix, _type) \
		case UniformType::_uniform: \
			{ \
				_type* value = (_type*)data; \
				GL_CHECK(glUniform##_glsuffix(loc, num, value) ); \
			} \
			break;
			
#define CASE_IMPLEMENT_UNIFORM_T(_uniform, _glsuffix, _dxsuffix, _type) \
		case UniformType::_uniform: \
			{ \
				_type* value = (_type*)data; \
				GL_CHECK(glUniform##_glsuffix(loc, num, GL_FALSE, value) ); \
			} \
			break;

			switch (type)
			{
// 			case ConstantType::Uniform1iv:
// 				{
// 					int* value = (int*)data;
// 					BX_TRACE("Uniform1iv sampler %d, loc %d (num %d, copy %d)", *value, loc, num, copy);
// 					GL_CHECK(glUniform1iv(loc, num, value) );
// 				}
// 				break;

			CASE_IMPLEMENT_UNIFORM(Uniform1i, 1iv, I, int);
			CASE_IMPLEMENT_UNIFORM(Uniform1f, 1fv, F, float);
			CASE_IMPLEMENT_UNIFORM(Uniform1iv, 1iv, I, int);
			CASE_IMPLEMENT_UNIFORM(Uniform1fv, 1fv, F, float);
			CASE_IMPLEMENT_UNIFORM(Uniform2fv, 2fv, F, float);
			CASE_IMPLEMENT_UNIFORM(Uniform3fv, 3fv, F, float);
			CASE_IMPLEMENT_UNIFORM(Uniform4fv, 4fv, F, float);
			CASE_IMPLEMENT_UNIFORM_T(Uniform3x3fv, Matrix3fv, F, float);
			CASE_IMPLEMENT_UNIFORM_T(Uniform4x4fv, Matrix4fv, F, float);

			case UniformType::End:
				break;

			default:
				BX_TRACE("%4d: INVALID 0x%08x, t %d, l %d, n %d, c %d", m_pos, opcode, type, loc, num, copy);
				break;
			}

#undef CASE_IMPLEMENT_UNIFORM
#undef CASE_IMPLEMENT_UNIFORM_T

		} while (true);
	}

	void TextVideoMemBlitter::setup()
	{
		if (0 != s_renderCtx->m_vao)
		{
			GL_CHECK(glBindVertexArray(s_renderCtx->m_vao) );
		}

		uint32_t width = s_renderCtx->m_resolution.m_width;
		uint32_t height = s_renderCtx->m_resolution.m_height;

		GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, s_renderCtx->m_backBufferFbo) );
		GL_CHECK(glViewport(0, 0, width, height) );

		GL_CHECK(glDisable(GL_SCISSOR_TEST) );
		GL_CHECK(glDisable(GL_STENCIL_TEST) );
		GL_CHECK(glDisable(GL_DEPTH_TEST) );
		GL_CHECK(glDepthFunc(GL_ALWAYS) );
		GL_CHECK(glDisable(GL_CULL_FACE) );
		GL_CHECK(glDisable(GL_BLEND) );
		GL_CHECK(glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );

		Program& program = s_renderCtx->m_program[m_program.idx];
		GL_CHECK(glUseProgram(program.m_id) );
		GL_CHECK(glUniform1i(program.m_sampler[0], 0) );

		float proj[16];
		mtxOrtho(proj, 0.0f, (float)width, (float)height, 0.0f, 0.0f, 1000.0f);

		GL_CHECK(glUniformMatrix4fv(program.m_predefined[0].m_loc
			, 1
			, GL_FALSE
			, proj
			) );

		GL_CHECK(glActiveTexture(GL_TEXTURE0) );
		GL_CHECK(glBindTexture(GL_TEXTURE_2D, s_renderCtx->m_textures[m_texture.idx].m_id) );
	}

	void TextVideoMemBlitter::render(uint32_t _numIndices)
	{
		uint32_t numVertices = _numIndices*4/6;
		s_renderCtx->m_indexBuffers[m_ib->handle.idx].update(0, _numIndices*2, m_ib->data);
		s_renderCtx->m_vertexBuffers[m_vb->handle.idx].update(0, numVertices*m_decl.m_stride, m_vb->data);

		VertexBuffer& vb = s_renderCtx->m_vertexBuffers[m_vb->handle.idx];
		GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, vb.m_id) );

		IndexBuffer& ib = s_renderCtx->m_indexBuffers[m_ib->handle.idx];
		GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ib.m_id) );

		Program& program = s_renderCtx->m_program[m_program.idx];
		program.bindAttributes(m_decl, 0);

		GL_CHECK(glDrawElements(GL_TRIANGLES
			, _numIndices
			, GL_UNSIGNED_SHORT
			, (void*)0
			) );
	}

	void ClearQuad::clear(const Rect& _rect, const Clear& _clear, uint32_t _height)
	{
#if BGFX_CONFIG_CLEAR_QUAD
		if (s_renderCtx->m_useClearQuad)
		{
			const GLuint defaultVao = s_renderCtx->m_vao;
			if (0 != defaultVao)
			{
				GL_CHECK(glBindVertexArray(defaultVao) );
			}

			GL_CHECK(glDisable(GL_SCISSOR_TEST) );
			GL_CHECK(glDisable(GL_CULL_FACE) );
			GL_CHECK(glDisable(GL_BLEND) );

			GLboolean colorMask = !!(BGFX_CLEAR_COLOR_BIT & _clear.m_flags);
			GL_CHECK(glColorMask(colorMask, colorMask, colorMask, colorMask) );

			if (BGFX_CLEAR_DEPTH_BIT & _clear.m_flags)
			{
				GL_CHECK(glEnable(GL_DEPTH_TEST) );
				GL_CHECK(glDepthFunc(GL_ALWAYS) );
				GL_CHECK(glDepthMask(GL_TRUE) );
			}
			else
			{
				GL_CHECK(glDisable(GL_DEPTH_TEST) );
			}

			if (BGFX_CLEAR_STENCIL_BIT & _clear.m_flags)
			{
				GL_CHECK(glEnable(GL_STENCIL_TEST) );
				GL_CHECK(glStencilFuncSeparate(GL_FRONT_AND_BACK, GL_ALWAYS, _clear.m_stencil,  0xff) );
				GL_CHECK(glStencilOpSeparate(GL_FRONT_AND_BACK, GL_REPLACE, GL_REPLACE, GL_REPLACE) );
			}
			else
			{
				GL_CHECK(glDisable(GL_STENCIL_TEST) );
			}

			VertexBuffer& vb = s_renderCtx->m_vertexBuffers[m_vb->handle.idx];
			VertexDecl& vertexDecl = s_renderCtx->m_vertexDecls[m_vb->decl.idx];

			{
				struct Vertex
				{
					float m_x;
					float m_y;
					float m_z;
					uint32_t m_abgr;
				} * vertex = (Vertex*)m_vb->data;
				BX_CHECK(vertexDecl.m_stride == sizeof(Vertex), "Stride/Vertex mismatch (stride %d, sizeof(Vertex) %d)", vertexDecl.m_stride, sizeof(Vertex) );

				const uint32_t abgr = bx::endianSwap(_clear.m_rgba);
				const float depth = _clear.m_depth;

				vertex->m_x = -1.0f;
				vertex->m_y = -1.0f;
				vertex->m_z = depth;
				vertex->m_abgr = abgr;
				vertex++;
				vertex->m_x =  1.0f;
				vertex->m_y = -1.0f;
				vertex->m_z = depth;
				vertex->m_abgr = abgr;
				vertex++;
				vertex->m_x =  1.0f;
				vertex->m_y =  1.0f;
				vertex->m_z = depth;
				vertex->m_abgr = abgr;
				vertex++;
				vertex->m_x = -1.0f;
				vertex->m_y =  1.0f;
				vertex->m_z = depth;
				vertex->m_abgr = abgr;
			}

			s_renderCtx->m_vertexBuffers[m_vb->handle.idx].update(0, 4*m_decl.m_stride, m_vb->data);

			GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, vb.m_id) );

			IndexBuffer& ib = s_renderCtx->m_indexBuffers[m_ib.idx];
			GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ib.m_id) );

			Program& program = s_renderCtx->m_program[m_program.idx];
			GL_CHECK(glUseProgram(program.m_id) );
			program.bindAttributes(vertexDecl, 0);

			GL_CHECK(glDrawElements(GL_TRIANGLES
				, 6
				, GL_UNSIGNED_SHORT
				, (void*)0
				) );
		}
		else
#endif // BGFX_CONFIG_CLEAR_QUAD
		{
			GLuint flags = 0;
			if (BGFX_CLEAR_COLOR_BIT & _clear.m_flags)
			{
				flags |= GL_COLOR_BUFFER_BIT;
				uint32_t rgba = _clear.m_rgba;
				float rr = (rgba>>24)/255.0f;
				float gg = ( (rgba>>16)&0xff)/255.0f;
				float bb = ( (rgba>>8)&0xff)/255.0f;
				float aa = (rgba&0xff)/255.0f;
				GL_CHECK(glClearColor(rr, gg, bb, aa) );
				GL_CHECK(glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE) );
			}

			if (BGFX_CLEAR_DEPTH_BIT & _clear.m_flags)
			{
				flags |= GL_DEPTH_BUFFER_BIT;
				GL_CHECK(glClearDepth(_clear.m_depth) );
				GL_CHECK(glDepthMask(GL_TRUE) );
			}

			if (BGFX_CLEAR_STENCIL_BIT & _clear.m_flags)
			{
				flags |= GL_STENCIL_BUFFER_BIT;
				GL_CHECK(glClearStencil(_clear.m_stencil) );
			}

			if (0 != flags)
			{
				GL_CHECK(glEnable(GL_SCISSOR_TEST) );
				GL_CHECK(glScissor(_rect.m_x, _height-_rect.m_height-_rect.m_y, _rect.m_width, _rect.m_height) );
				GL_CHECK(glClear(flags) );
				GL_CHECK(glDisable(GL_SCISSOR_TEST) );
			}
		}
	}

	void Context::rendererFlip()
	{
		if (NULL != s_renderCtx)
		{
			s_renderCtx->flip();
		}
	}

	GLint glGet(GLenum _pname)
	{
		GLint result;
		glGetIntegerv(_pname, &result);
		GLenum err = glGetError();
		BX_WARN(0 == err, "glGetIntegerv(0x%04x, ...) failed with GL error: 0x%04x.", _pname, err);
		BX_UNUSED(err);
		return result;
	}

	void Context::rendererInit()
	{
		s_renderCtx = BX_NEW(g_allocator, RendererContext);
		s_renderCtx->init();

#if BGFX_CONFIG_DEBUG
		GLint numCmpFormats;
		GL_CHECK(glGetIntegerv(GL_NUM_COMPRESSED_TEXTURE_FORMATS, &numCmpFormats) );

		BX_TRACE("GL_NUM_COMPRESSED_TEXTURE_FORMATS %d", numCmpFormats);

		if (0 < numCmpFormats)
		{
			static const char* s_textureFormatName[TextureFormat::Unknown+1] =
			{
				"BC1",
				"BC2",
				"BC3",
				"BC4",
				"BC5",
				"ETC1",
				"ETC2",
				"ETC2A",
				"ETC2A1",
				"PTC12",
				"PTC14",
				"PTC12A",
				"PTC14A",
				"PTC22",
				"PTC24",
				"",
				// TextureFormat::Count
			};

			GLint* formats = (GLint*)alloca(sizeof(GLint)*numCmpFormats);
			GL_CHECK(glGetIntegerv(GL_COMPRESSED_TEXTURE_FORMATS, formats) );

			for (GLint ii = 0; ii < numCmpFormats; ++ii)
			{
				GLint internalFmt = formats[ii];
				uint32_t fmt = uint32_t(TextureFormat::Unknown);
				for (uint32_t jj = 0; jj < fmt; ++jj)
				{
					if (s_textureFormat[jj].m_internalFmt == (GLenum)internalFmt)
					{
						fmt = jj;
					}
				}

				BX_TRACE("  %3d: %8x %s", ii, internalFmt, s_textureFormatName[fmt]);
			}
		}

#	define GL_GET(_pname, _min) BX_TRACE("  " #_pname " %d (min: %d)", glGet(_pname), _min)

		BX_TRACE("Defaults:");
#	if BX_PLATFORM_OSX
		GL_GET(GL_MAX_FRAGMENT_UNIFORM_COMPONENTS, 16 * 4);
		GL_GET(GL_MAX_VERTEX_UNIFORM_COMPONENTS, 128 * 4);
		GL_GET(GL_MAX_VARYING_FLOATS, 8 * 4);
#	else
		GL_GET(GL_MAX_FRAGMENT_UNIFORM_VECTORS, 16);
		GL_GET(GL_MAX_VERTEX_UNIFORM_VECTORS, 128);
		GL_GET(GL_MAX_VARYING_VECTORS, 8);
#	endif
		GL_GET(GL_MAX_VERTEX_ATTRIBS, 8);
		GL_GET(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, 8);
		GL_GET(GL_MAX_CUBE_MAP_TEXTURE_SIZE, 16);
		GL_GET(GL_MAX_TEXTURE_IMAGE_UNITS, 8);
		GL_GET(GL_MAX_TEXTURE_SIZE, 64);
		GL_GET(GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS, 0);
		GL_GET(GL_MAX_RENDERBUFFER_SIZE, 1);

		BX_TRACE("      Vendor: %s", s_renderCtx->m_vendor);
		BX_TRACE("    Renderer: %s", s_renderCtx->m_renderer);
		BX_TRACE("     Version: %s", s_renderCtx->m_version);
		BX_TRACE("GLSL version: %s", s_renderCtx->m_glslVersion);
#endif // BGFX_CONFIG_DEBUG

		// Initial binary shader hash depends on driver version.
		s_renderCtx->m_hash = ( (BX_PLATFORM_WINDOWS<<1) | BX_ARCH_64BIT)
						^ (uint64_t(getGLStringHash(GL_VENDOR  ) )<<32)
						^ (uint64_t(getGLStringHash(GL_RENDERER) )<<0 )
						^ (uint64_t(getGLStringHash(GL_VERSION ) )<<16)
						;

#if BGFX_CONFIG_RENDERER_USE_EXTENSIONS
		const char* extensions = (const char*)glGetString(GL_EXTENSIONS);
		glGetError(); // ignore error if glGetString returns NULL.
		if (NULL != extensions)
		{
			char name[1024];
			const char* pos = extensions;
			const char* end = extensions + strlen(extensions);
			uint32_t index = 0;
			while (pos < end)
			{
				uint32_t len;
				const char* space = strchr(pos, ' ');
				if (NULL != space)
				{
					len = bx::uint32_min(sizeof(name), (uint32_t)(space - pos) );
				}
				else
				{
					len = bx::uint32_min(sizeof(name), (uint32_t)strlen(pos) );
				}
				
				strncpy(name, pos, len);
				name[len] = '\0';

				bool supported = false;
				for (uint32_t ii = 0; ii < Extension::Count; ++ii)
				{
					Extension& extension = s_extension[ii];
					if (!extension.m_supported
					&&  extension.m_initialize)
					{
						if (0 == strcmp(name, extension.m_name) )
						{
							extension.m_supported = true;
							supported = true;
							break;
						}
					}
				}

				BX_TRACE("GL_EXTENSION %3d%s: %s", index, supported ? " (supported)" : "", name);
				BX_UNUSED(supported);

 				pos += len+1;
				++index;
 			}

			BX_TRACE("Supported extensions:");
			for (uint32_t ii = 0; ii < Extension::Count; ++ii)
			{
				if (s_extension[ii].m_supported)
				{
					BX_TRACE("\t%2d: %s", ii, s_extension[ii].m_name);
				}
			}
		}
#endif // BGFX_CONFIG_RENDERER_OPENGL_USE_EXTENSIONS

		bool bc123Supported = s_extension[Extension::EXT_texture_compression_s3tc].m_supported;
		s_textureFormat[TextureFormat::BC1].m_supported = bc123Supported || s_extension[Extension::EXT_texture_compression_dxt1].m_supported;
		s_textureFormat[TextureFormat::BC2].m_supported = bc123Supported || s_extension[Extension::CHROMIUM_texture_compression_dxt3].m_supported;
		s_textureFormat[TextureFormat::BC3].m_supported = bc123Supported || s_extension[Extension::CHROMIUM_texture_compression_dxt5].m_supported;

		bool bc45Supported = s_extension[Extension::EXT_texture_compression_latc].m_supported
			|| s_extension[Extension::EXT_texture_compression_rgtc].m_supported
			;
		s_textureFormat[TextureFormat::BC4].m_supported = bc45Supported;
		s_textureFormat[TextureFormat::BC5].m_supported = bc45Supported;

		s_textureFormat[TextureFormat::ETC1].m_supported = s_extension[Extension::OES_compressed_ETC1_RGB8_texture].m_supported;

		bool etc2Supported = !!BGFX_CONFIG_RENDERER_OPENGLES3
			|| s_extension[Extension::ARB_ES3_compatibility].m_supported
			;
		s_textureFormat[TextureFormat::ETC2  ].m_supported = etc2Supported;
		s_textureFormat[TextureFormat::ETC2A ].m_supported = etc2Supported;
		s_textureFormat[TextureFormat::ETC2A1].m_supported = etc2Supported;

		if (!s_textureFormat[TextureFormat::ETC1].m_supported
		&&  etc2Supported)
		{
			// When ETC2 is supported override ETC1 texture format settings.
			s_textureFormat[TextureFormat::ETC1].m_internalFmt = GL_COMPRESSED_RGB8_ETC2;
			s_textureFormat[TextureFormat::ETC1].m_fmt         = GL_COMPRESSED_RGB8_ETC2;
			s_textureFormat[TextureFormat::ETC1].m_supported   = true;
		}

		bool ptc1Supported = s_extension[Extension::IMG_texture_compression_pvrtc ].m_supported;
		s_textureFormat[TextureFormat::PTC12].m_supported  = ptc1Supported;
		s_textureFormat[TextureFormat::PTC14].m_supported  = ptc1Supported;
		s_textureFormat[TextureFormat::PTC12A].m_supported = ptc1Supported;
		s_textureFormat[TextureFormat::PTC14A].m_supported = ptc1Supported;

		bool ptc2Supported = s_extension[Extension::IMG_texture_compression_pvrtc2].m_supported;
		s_textureFormat[TextureFormat::PTC22].m_supported  = ptc2Supported;
		s_textureFormat[TextureFormat::PTC24].m_supported  = ptc2Supported;

		s_renderCtx->m_vaoSupport = !!BGFX_CONFIG_RENDERER_OPENGLES3
			|| s_extension[Extension::ARB_vertex_array_object].m_supported
			|| s_extension[Extension::OES_vertex_array_object].m_supported
			;

#if BX_PLATFORM_NACL
		s_renderCtx->m_vaoSupport &= NULL != glGenVertexArrays
								  && NULL != glDeleteVertexArrays
								  && NULL != glBindVertexArray
								  ;
#endif // BX_PLATFORM_NACL

		if (s_renderCtx->m_vaoSupport)
		{
			GL_CHECK(glGenVertexArrays(1, &s_renderCtx->m_vao) );
		}

		s_renderCtx->m_samplerObjectSupport = !!BGFX_CONFIG_RENDERER_OPENGLES3
			|| s_extension[Extension::ARB_sampler_objects].m_supported
			;

		s_renderCtx->m_programBinarySupport = !!BGFX_CONFIG_RENDERER_OPENGLES3
			|| s_extension[Extension::ARB_get_program_binary].m_supported
			|| s_extension[Extension::OES_get_program_binary].m_supported
			|| s_extension[Extension::IMG_shader_binary].m_supported
			;

		s_renderCtx->m_textureSwizzleSupport = false
			|| s_extension[Extension::ARB_texture_swizzle].m_supported
			|| s_extension[Extension::EXT_texture_swizzle].m_supported
			;

		if (s_extension[Extension::EXT_texture_filter_anisotropic].m_supported)
		{
			GL_CHECK(glGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &s_renderCtx->m_maxAnisotropy) );
		}

#if BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3
		if (s_extension[Extension::ARB_texture_multisample].m_supported)
		{
			GL_CHECK(glGetIntegerv(GL_MAX_SAMPLES, &s_renderCtx->m_maxMsaa) );
		}
#endif // BGFX_CONFIG_RENDERER_OPENGL|BGFX_CONFIG_RENDERER_OPENGLES3

		if (s_extension[Extension::IMG_read_format].m_supported
		&&  s_extension[Extension::OES_read_format].m_supported)
		{
			s_renderCtx->m_readPixelsFmt = GL_BGRA_EXT;
		}
		else
		{
			s_renderCtx->m_readPixelsFmt = GL_RGBA;
		}

		if (s_extension[Extension::EXT_texture_format_BGRA8888].m_supported
		||  s_extension[Extension::EXT_bgra].m_supported
		||  s_extension[Extension::IMG_texture_format_BGRA8888].m_supported
		||  s_extension[Extension::APPLE_texture_format_BGRA8888].m_supported)
		{
#if BGFX_CONFIG_RENDERER_OPENGL
			s_renderCtx->m_readPixelsFmt = GL_BGRA_EXT;
#endif // BGFX_CONFIG_RENDERER_OPENGL

			s_textureFormat[TextureFormat::BGRA8].m_fmt = GL_BGRA_EXT;

			// Mixing GLES and GL extensions here. OpenGL EXT_bgra wants
			// format to be BGRA but internal format to stay RGBA, but 
			// EXT_texture_format_BGRA8888 wants both format and internal
			// format to be BGRA.
			//
			// Reference:
			// https://www.khronos.org/registry/gles/extensions/EXT/EXT_texture_format_BGRA8888.txt
			// https://www.opengl.org/registry/specs/EXT/bgra.txt
			if (!s_extension[Extension::EXT_bgra].m_supported)
			{
				s_textureFormat[TextureFormat::BGRA8].m_internalFmt = GL_BGRA_EXT;
			}
		}

		if (s_extension[Extension::EXT_texture_compression_rgtc].m_supported)
		{
			s_textureFormat[TextureFormat::BC4].m_fmt = GL_COMPRESSED_RED_RGTC1_EXT;
			s_textureFormat[TextureFormat::BC4].m_internalFmt = GL_COMPRESSED_RED_RGTC1_EXT;
			s_textureFormat[TextureFormat::BC5].m_fmt = GL_COMPRESSED_RED_GREEN_RGTC2_EXT;
			s_textureFormat[TextureFormat::BC5].m_internalFmt = GL_COMPRESSED_RED_GREEN_RGTC2_EXT;
		}

#if !BGFX_CONFIG_RENDERER_OPENGLES3
		s_vertexAttribDivisor = stubVertexAttribDivisor;
		s_drawArraysInstanced = stubDrawArraysInstanced;
		s_drawElementsInstanced = stubDrawElementsInstanced;

#	if !BX_PLATFORM_IOS
		if (s_extension[Extension::ARB_instanced_arrays].m_supported
		||  s_extension[Extension::ANGLE_instanced_arrays].m_supported)
		{
			if (NULL != glVertexAttribDivisor
			&&  NULL != glDrawArraysInstanced
			&&  NULL != glDrawElementsInstanced)
			{
				s_vertexAttribDivisor   = glVertexAttribDivisor;
				s_drawArraysInstanced   = glDrawArraysInstanced;
				s_drawElementsInstanced = glDrawElementsInstanced;
			}
		}
#	endif // !BX_PLATFORM_IOS
#endif // !BGFX_CONFIG_RENDERER_OPENGLES3

#if BGFX_CONFIG_RENDERER_OPENGL
#	if BGFX_CONFIG_RENDERER_OPENGL >= 31
		s_textureFormat[TextureFormat::L8].m_internalFmt = GL_R8;
		s_textureFormat[TextureFormat::L8].m_fmt         = GL_RED;
#	endif // BGFX_CONFIG_RENDERER_OPENGL >= 31

		if (s_extension[Extension::ARB_debug_output].m_supported)
		{
			GL_CHECK(glDebugMessageCallbackARB(debugProcCb, NULL) );
			GL_CHECK(glDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_MEDIUM_ARB, 0, NULL, GL_TRUE) );
		}

		if (s_extension[Extension::ARB_seamless_cube_map].m_supported)
		{
			GL_CHECK(glEnable(GL_TEXTURE_CUBE_MAP_SEAMLESS) );
		}

		if (s_extension[Extension::ARB_depth_clamp].m_supported)
		{
			GL_CHECK(glEnable(GL_DEPTH_CLAMP) );
		}
#endif // BGFX_CONFIG_RENDERER_OPENGL
	}

	void Context::rendererShutdown()
	{
		if (s_renderCtx->m_vaoSupport)
		{
			GL_CHECK(glBindVertexArray(0) );
			GL_CHECK(glDeleteVertexArrays(1, &s_renderCtx->m_vao) );
			s_renderCtx->m_vao = 0;
		}

		s_renderCtx->shutdown();

		BX_DELETE(g_allocator, s_renderCtx);
		s_renderCtx = NULL;
	}

	void Context::rendererCreateIndexBuffer(IndexBufferHandle _handle, Memory* _mem)
	{
		s_renderCtx->m_indexBuffers[_handle.idx].create(_mem->size, _mem->data);
	}

	void Context::rendererDestroyIndexBuffer(IndexBufferHandle _handle)
	{
		s_renderCtx->m_indexBuffers[_handle.idx].destroy();
	}

	void Context::rendererCreateVertexDecl(VertexDeclHandle _handle, const VertexDecl& _decl)
	{
		VertexDecl& decl = s_renderCtx->m_vertexDecls[_handle.idx];
		memcpy(&decl, &_decl, sizeof(VertexDecl) );
		dump(decl);
	}

	void Context::rendererDestroyVertexDecl(VertexDeclHandle /*_handle*/)
	{
	}

	void Context::rendererCreateVertexBuffer(VertexBufferHandle _handle, Memory* _mem, VertexDeclHandle _declHandle)
	{
		s_renderCtx->m_vertexBuffers[_handle.idx].create(_mem->size, _mem->data, _declHandle);
	}

	void Context::rendererDestroyVertexBuffer(VertexBufferHandle _handle)
	{
		s_renderCtx->m_vertexBuffers[_handle.idx].destroy();
	}

	void Context::rendererCreateDynamicIndexBuffer(IndexBufferHandle _handle, uint32_t _size)
	{
		s_renderCtx->m_indexBuffers[_handle.idx].create(_size, NULL);
	}

	void Context::rendererUpdateDynamicIndexBuffer(IndexBufferHandle _handle, uint32_t _offset, uint32_t _size, Memory* _mem)
	{
		s_renderCtx->m_indexBuffers[_handle.idx].update(_offset, bx::uint32_min(_size, _mem->size), _mem->data);
	}

	void Context::rendererDestroyDynamicIndexBuffer(IndexBufferHandle _handle)
	{
		s_renderCtx->m_indexBuffers[_handle.idx].destroy();
	}

	void Context::rendererCreateDynamicVertexBuffer(VertexBufferHandle _handle, uint32_t _size)
	{
		VertexDeclHandle decl = BGFX_INVALID_HANDLE;
		s_renderCtx->m_vertexBuffers[_handle.idx].create(_size, NULL, decl);
	}

	void Context::rendererUpdateDynamicVertexBuffer(VertexBufferHandle _handle, uint32_t _offset, uint32_t _size, Memory* _mem)
	{
		s_renderCtx->m_vertexBuffers[_handle.idx].update(_offset, bx::uint32_min(_size, _mem->size), _mem->data);
	}

	void Context::rendererDestroyDynamicVertexBuffer(VertexBufferHandle _handle)
	{
		s_renderCtx->m_vertexBuffers[_handle.idx].destroy();
	}

	void Context::rendererCreateVertexShader(VertexShaderHandle _handle, Memory* _mem)
	{
		s_renderCtx->m_vertexShaders[_handle.idx].create(GL_VERTEX_SHADER, _mem);
	}

	void Context::rendererDestroyVertexShader(VertexShaderHandle _handle)
	{
		s_renderCtx->m_vertexShaders[_handle.idx].destroy();
	}

	void Context::rendererCreateFragmentShader(FragmentShaderHandle _handle, Memory* _mem)
	{
		s_renderCtx->m_fragmentShaders[_handle.idx].create(GL_FRAGMENT_SHADER, _mem);
	}

	void Context::rendererDestroyFragmentShader(FragmentShaderHandle _handle)
	{
		s_renderCtx->m_fragmentShaders[_handle.idx].destroy();
	}

	void Context::rendererCreateProgram(ProgramHandle _handle, VertexShaderHandle _vsh, FragmentShaderHandle _fsh)
	{
		s_renderCtx->m_program[_handle.idx].create(s_renderCtx->m_vertexShaders[_vsh.idx], s_renderCtx->m_fragmentShaders[_fsh.idx]);
	}

	void Context::rendererDestroyProgram(FragmentShaderHandle _handle)
	{
		s_renderCtx->m_program[_handle.idx].destroy();
	}

	void Context::rendererCreateTexture(TextureHandle _handle, Memory* _mem, uint32_t _flags)
	{
		s_renderCtx->m_textures[_handle.idx].create(_mem, _flags);
	}

	void Context::rendererUpdateTextureBegin(TextureHandle /*_handle*/, uint8_t /*_side*/, uint8_t /*_mip*/)
	{
	}

	void Context::rendererUpdateTexture(TextureHandle _handle, uint8_t _side, uint8_t _mip, const Rect& _rect, uint16_t _z, uint16_t _depth, const Memory* _mem)
	{
		s_renderCtx->m_textures[_handle.idx].update(_side, _mip, _rect, _z, _depth, _mem);
	}

	void Context::rendererUpdateTextureEnd()
	{
	}

	void Context::rendererDestroyTexture(TextureHandle _handle)
	{
		s_renderCtx->m_textures[_handle.idx].destroy();
	}

	void Context::rendererCreateRenderTarget(RenderTargetHandle _handle, uint16_t _width, uint16_t _height, uint32_t _flags, uint32_t _textureFlags)
	{
		s_renderCtx->m_renderTargets[_handle.idx].create(_width, _height, _flags, _textureFlags);
	}

	void Context::rendererDestroyRenderTarget(RenderTargetHandle _handle)
	{
		s_renderCtx->m_renderTargets[_handle.idx].destroy();
	}

	void Context::rendererCreateUniform(UniformHandle _handle, UniformType::Enum _type, uint16_t _num, const char* _name)
	{
		uint32_t size = g_uniformTypeSize[_type]*_num;
		void* data = BX_ALLOC(g_allocator, size);
		memset(data, 0, size);
		s_renderCtx->m_uniforms[_handle.idx] = data;
		s_renderCtx->m_uniformReg.add(_name, s_renderCtx->m_uniforms[_handle.idx]);
	}

	void Context::rendererDestroyUniform(UniformHandle _handle)
	{
		BX_FREE(g_allocator, s_renderCtx->m_uniforms[_handle.idx]);
	}

	void Context::rendererSaveScreenShot(const char* _filePath)
	{
		s_renderCtx->saveScreenShot(_filePath);
	}

	void Context::rendererUpdateViewName(uint8_t _id, const char* _name)
	{
		bx::strlcpy(&s_viewName[_id][0], _name, sizeof(s_viewName[0][0]) );
	}

	void Context::rendererUpdateUniform(uint16_t _loc, const void* _data, uint32_t _size)
	{
		memcpy(s_renderCtx->m_uniforms[_loc], _data, _size);
	}

	void Context::rendererSetMarker(const char* _marker, uint32_t /*_size*/)
	{
		GREMEDY_SETMARKER(_marker);
	}

	void Context::rendererSubmit()
	{
		const GLuint defaultVao = s_renderCtx->m_vao;
		if (0 != defaultVao)
		{
			GL_CHECK(glBindVertexArray(defaultVao) );
		}

		GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, s_renderCtx->m_backBufferFbo) );

		s_renderCtx->updateResolution(m_render->m_resolution);

		int64_t elapsed = -bx::getHPCounter();
		int64_t captureElapsed = 0;

#if BGFX_CONFIG_RENDERER_OPENGL
		if (m_render->m_debug & (BGFX_DEBUG_IFH|BGFX_DEBUG_STATS) )
		{
			s_renderCtx->m_queries.begin(0, GL_TIME_ELAPSED);
		}
#endif // BGFX_CONFIG_RENDERER_OPENGL

		if (0 < m_render->m_iboffset)
		{
			TransientIndexBuffer* ib = m_render->m_transientIb;
			s_renderCtx->m_indexBuffers[ib->handle.idx].update(0, m_render->m_iboffset, ib->data);
		}

		if (0 < m_render->m_vboffset)
		{
			TransientVertexBuffer* vb = m_render->m_transientVb;
			s_renderCtx->m_vertexBuffers[vb->handle.idx].update(0, m_render->m_vboffset, vb->data);
		}

		m_render->sort();

		RenderState currentState;
		currentState.reset();
		currentState.m_flags = BGFX_STATE_NONE;
		currentState.m_stencil = packStencil(BGFX_STENCIL_NONE, BGFX_STENCIL_NONE);

		Matrix4 viewProj[BGFX_CONFIG_MAX_VIEWS];
		for (uint32_t ii = 0; ii < BGFX_CONFIG_MAX_VIEWS; ++ii)
		{
			mtxMul(viewProj[ii].val, m_render->m_view[ii].val, m_render->m_proj[ii].val);
		}

		uint16_t programIdx = invalidHandle;
		SortKey key;
		uint8_t view = 0xff;
		RenderTargetHandle rt = BGFX_INVALID_HANDLE;
		int32_t height = m_render->m_resolution.m_height;
		float alphaRef = 0.0f;
		uint32_t blendFactor = 0;
		GLenum primType = m_render->m_debug&BGFX_DEBUG_WIREFRAME ? GL_LINES : GL_TRIANGLES;
		uint32_t primNumVerts = 3;
		uint32_t baseVertex = 0;
		GLuint currentVao = 0;
		bool viewHasScissor = false;
		Rect viewScissorRect;
		viewScissorRect.clear();

		uint32_t statsNumPrimsSubmitted = 0;
		uint32_t statsNumIndices = 0;
		uint32_t statsNumInstances = 0;
		uint32_t statsNumPrimsRendered = 0;

		if (0 == (m_render->m_debug&BGFX_DEBUG_IFH) )
		{
			GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, s_renderCtx->m_msaaBackBufferFbo) );

			for (uint32_t item = 0, numItems = m_render->m_num; item < numItems; ++item)
			{
				key.decode(m_render->m_sortKeys[item]);
				const RenderState& state = m_render->m_renderState[m_render->m_sortValues[item] ];

				const uint64_t newFlags = state.m_flags;
				uint64_t changedFlags = currentState.m_flags ^ state.m_flags;
				currentState.m_flags = newFlags;

				const uint64_t newStencil = state.m_stencil;
				uint64_t changedStencil = currentState.m_stencil ^ state.m_stencil;
				currentState.m_stencil = newStencil;

				if (key.m_view != view)
				{
					currentState.clear();
					currentState.m_scissor = !state.m_scissor;
					changedFlags = BGFX_STATE_MASK;
					changedStencil = packStencil(BGFX_STENCIL_MASK, BGFX_STENCIL_MASK);
					currentState.m_flags = newFlags;
					currentState.m_stencil = newStencil;

					GREMEDY_SETMARKER(s_viewName[key.m_view]);

					view = key.m_view;
					programIdx = invalidHandle;

					if (m_render->m_rt[view].idx != rt.idx)
					{
						rt = m_render->m_rt[view];
						height = s_renderCtx->setRenderTarget(rt, m_render->m_resolution.m_height);
					}

					const Rect& rect = m_render->m_rect[view];
					const Rect& scissorRect = m_render->m_scissor[view];
					viewHasScissor = !scissorRect.isZero();
					viewScissorRect = viewHasScissor ? scissorRect : rect;

					GL_CHECK(glViewport(rect.m_x, height-rect.m_height-rect.m_y, rect.m_width, rect.m_height) );

					Clear& clear = m_render->m_clear[view];

					if (BGFX_CLEAR_NONE != clear.m_flags)
					{
						m_clearQuad.clear(rect, clear, height);
					}

					GL_CHECK(glDisable(GL_STENCIL_TEST) );
					GL_CHECK(glEnable(GL_DEPTH_TEST) );
					GL_CHECK(glDepthFunc(GL_LESS) );
					GL_CHECK(glEnable(GL_CULL_FACE) );
					GL_CHECK(glDisable(GL_BLEND) );
				}

				uint16_t scissor = state.m_scissor;
				if (currentState.m_scissor != scissor)
				{
					currentState.m_scissor = scissor;

					if (UINT16_MAX == scissor)
					{
						if (viewHasScissor)
						{
							GL_CHECK(glEnable(GL_SCISSOR_TEST) );
							GL_CHECK(glScissor(viewScissorRect.m_x, height-viewScissorRect.m_height-viewScissorRect.m_y, viewScissorRect.m_width, viewScissorRect.m_height) );
						}
						else
						{
							GL_CHECK(glDisable(GL_SCISSOR_TEST) );
						}
					}
					else
					{
						Rect scissorRect;
						scissorRect.intersect(viewScissorRect, m_render->m_rectCache.m_cache[scissor]);
						GL_CHECK(glEnable(GL_SCISSOR_TEST) );
						GL_CHECK(glScissor(scissorRect.m_x, height-scissorRect.m_height-scissorRect.m_y, scissorRect.m_width, scissorRect.m_height) );
					}
				}

				if (0 != changedStencil)
				{
					if (0 != newStencil)
					{
						GL_CHECK(glEnable(GL_STENCIL_TEST) );

						uint32_t bstencil = unpackStencil(1, newStencil);
						uint32_t frontAndBack = bstencil != BGFX_STENCIL_NONE && bstencil != unpackStencil(0, newStencil);

// 						uint32_t bchanged = unpackStencil(1, changedStencil);
// 						if (BGFX_STENCIL_FUNC_RMASK_MASK & bchanged)
// 						{
// 							uint32_t wmask = (bstencil&BGFX_STENCIL_FUNC_RMASK_MASK)>>BGFX_STENCIL_FUNC_RMASK_SHIFT;
// 							GL_CHECK(glStencilMask(wmask) );
// 						}

						for (uint32_t ii = 0, num = frontAndBack+1; ii < num; ++ii)
						{
							uint32_t stencil = unpackStencil(ii, newStencil);
							uint32_t changed = unpackStencil(ii, changedStencil);
							GLenum face = s_stencilFace[frontAndBack+ii];

							if ( (BGFX_STENCIL_TEST_MASK|BGFX_STENCIL_FUNC_REF_MASK|BGFX_STENCIL_FUNC_RMASK_MASK) & changed)
							{
								GLint ref = (stencil&BGFX_STENCIL_FUNC_REF_MASK)>>BGFX_STENCIL_FUNC_REF_SHIFT;
								GLint mask = (stencil&BGFX_STENCIL_FUNC_RMASK_MASK)>>BGFX_STENCIL_FUNC_RMASK_SHIFT;
								uint32_t func = (stencil&BGFX_STENCIL_TEST_MASK)>>BGFX_STENCIL_TEST_SHIFT;
								GL_CHECK(glStencilFuncSeparate(face, s_stencilFunc[func], ref, mask));
							}

							if ( (BGFX_STENCIL_OP_FAIL_S_MASK|BGFX_STENCIL_OP_FAIL_Z_MASK|BGFX_STENCIL_OP_PASS_Z_MASK) & changed)
							{
								uint32_t sfail = (stencil&BGFX_STENCIL_OP_FAIL_S_MASK)>>BGFX_STENCIL_OP_FAIL_S_SHIFT;
								uint32_t zfail = (stencil&BGFX_STENCIL_OP_FAIL_Z_MASK)>>BGFX_STENCIL_OP_FAIL_Z_SHIFT;
								uint32_t zpass = (stencil&BGFX_STENCIL_OP_PASS_Z_MASK)>>BGFX_STENCIL_OP_PASS_Z_SHIFT;
								GL_CHECK(glStencilOpSeparate(face, s_stencilOp[sfail], s_stencilOp[zfail], s_stencilOp[zpass]) );
							}
						}
					}
					else
					{
						GL_CHECK(glDisable(GL_STENCIL_TEST) );
					}
				}

				if ( (0
					 | BGFX_STATE_CULL_MASK
					 | BGFX_STATE_DEPTH_WRITE
					 | BGFX_STATE_DEPTH_TEST_MASK
					 | BGFX_STATE_ALPHA_MASK
					 | BGFX_STATE_RGB_WRITE
					 | BGFX_STATE_BLEND_MASK
					 | BGFX_STATE_BLEND_EQUATION_MASK
					 | BGFX_STATE_ALPHA_REF_MASK
					 | BGFX_STATE_PT_MASK
					 | BGFX_STATE_POINT_SIZE_MASK
					 | BGFX_STATE_MSAA
					 ) & changedFlags)
				{
					if (BGFX_STATE_CULL_MASK & changedFlags)
					{
						if (BGFX_STATE_CULL_CW & newFlags)
						{
							GL_CHECK(glEnable(GL_CULL_FACE) );
							GL_CHECK(glCullFace(GL_BACK) );
						}
						else if (BGFX_STATE_CULL_CCW & newFlags)
						{
							GL_CHECK(glEnable(GL_CULL_FACE) );
							GL_CHECK(glCullFace(GL_FRONT) );
						}
						else
						{
							GL_CHECK(glDisable(GL_CULL_FACE) );
						}
					}

					if (BGFX_STATE_DEPTH_WRITE & changedFlags)
					{
						GL_CHECK(glDepthMask(!!(BGFX_STATE_DEPTH_WRITE & newFlags) ) );
					}

					if (BGFX_STATE_DEPTH_TEST_MASK & changedFlags)
					{
						uint32_t func = (newFlags&BGFX_STATE_DEPTH_TEST_MASK)>>BGFX_STATE_DEPTH_TEST_SHIFT;

						if (0 != func)
						{
							GL_CHECK(glEnable(GL_DEPTH_TEST) );
							GL_CHECK(glDepthFunc(s_depthFunc[func]) );
						}
						else
						{
							GL_CHECK(glDisable(GL_DEPTH_TEST) );
						}
					}

					if (BGFX_STATE_ALPHA_REF_MASK & changedFlags)
					{
						uint32_t ref = (newFlags&BGFX_STATE_ALPHA_REF_MASK)>>BGFX_STATE_ALPHA_REF_SHIFT;
						alphaRef = ref/255.0f;
					}

#if BGFX_CONFIG_RENDERER_OPENGL
					if ( (BGFX_STATE_PT_POINTS|BGFX_STATE_POINT_SIZE_MASK) & changedFlags)
					{
						float pointSize = (float)(bx::uint32_max(1, (newFlags&BGFX_STATE_POINT_SIZE_MASK)>>BGFX_STATE_POINT_SIZE_SHIFT) );
						GL_CHECK(glPointSize(pointSize) );
					}

					if (BGFX_STATE_MSAA & changedFlags)
					{
						if (BGFX_STATE_MSAA & newFlags)
						{
							GL_CHECK(glEnable(GL_MULTISAMPLE) );
						}
						else
						{
							GL_CHECK(glDisable(GL_MULTISAMPLE) );
						}
					}
#endif // BGFX_CONFIG_RENDERER_OPENGL

					if ( (BGFX_STATE_ALPHA_WRITE|BGFX_STATE_RGB_WRITE) & changedFlags)
					{
						GLboolean alpha = !!(newFlags&BGFX_STATE_ALPHA_WRITE);
						GLboolean rgb = !!(newFlags&BGFX_STATE_RGB_WRITE);
						GL_CHECK(glColorMask(rgb, rgb, rgb, alpha) );
					}

					if ( (BGFX_STATE_BLEND_MASK|BGFX_STATE_BLEND_EQUATION_MASK) & changedFlags)
					{
						if (BGFX_STATE_BLEND_MASK & newFlags)
						{
							uint32_t blend = (newFlags&BGFX_STATE_BLEND_MASK)>>BGFX_STATE_BLEND_SHIFT;
							uint32_t equation = (newFlags&BGFX_STATE_BLEND_EQUATION_MASK)>>BGFX_STATE_BLEND_EQUATION_SHIFT;
							uint32_t src = blend&0xf;
							uint32_t dst = (blend>>4)&0xf;
							GL_CHECK(glEnable(GL_BLEND) );
							GL_CHECK(glBlendFunc(s_blendFactor[src].m_src, s_blendFactor[dst].m_dst) );
							GL_CHECK(glBlendEquation(s_blendEquation[equation]) );

							if ( (s_blendFactor[src].m_factor || s_blendFactor[dst].m_factor)
							&&  blendFactor != state.m_rgba)
							{
								blendFactor = state.m_rgba;

								GLclampf rr = (blendFactor>>24)/255.0f;
								GLclampf gg = ( (blendFactor>>16)&0xff)/255.0f;
								GLclampf bb = ( (blendFactor>>8)&0xff)/255.0f;
								GLclampf aa = (blendFactor&0xff)/255.0f;

								GL_CHECK(glBlendColor(rr, gg, bb, aa) );
							}
						}
						else
						{
							GL_CHECK(glDisable(GL_BLEND) );
						}
					}

					uint8_t primIndex = uint8_t( (newFlags&BGFX_STATE_PT_MASK)>>BGFX_STATE_PT_SHIFT);
					primType = m_render->m_debug&BGFX_DEBUG_WIREFRAME ? GL_LINES : s_primType[primIndex];
					primNumVerts = 3-primIndex;
				}

				bool programChanged = false;
				bool constantsChanged = state.m_constBegin < state.m_constEnd;
				bool bindAttribs = false;
				rendererUpdateUniforms(m_render->m_constantBuffer, state.m_constBegin, state.m_constEnd);

				if (key.m_program != programIdx)
				{
					programIdx = key.m_program;
					GLuint id = invalidHandle == programIdx ? 0 : s_renderCtx->m_program[programIdx].m_id;
					GL_CHECK(glUseProgram(id) );
					programChanged = 
						constantsChanged = 
						bindAttribs = true;
				}

				if (invalidHandle != programIdx)
				{
					Program& program = s_renderCtx->m_program[programIdx];

					if (constantsChanged)
					{
						program.commit();
					}

					for (uint32_t ii = 0, num = program.m_numPredefined; ii < num; ++ii)
					{
						PredefinedUniform& predefined = program.m_predefined[ii];
						switch (predefined.m_type)
						{
						case PredefinedUniform::ViewRect:
							{
								float rect[4];
								rect[0] = m_render->m_rect[view].m_x;
								rect[1] = m_render->m_rect[view].m_y;
								rect[2] = m_render->m_rect[view].m_width;
								rect[3] = m_render->m_rect[view].m_height;

								GL_CHECK(glUniform4fv(predefined.m_loc
									, 1
									, &rect[0]
								) );
							}
							break;

						case PredefinedUniform::ViewTexel:
							{
								float rect[4];
								rect[0] = 1.0f/float(m_render->m_rect[view].m_width);
								rect[1] = 1.0f/float(m_render->m_rect[view].m_height);

								GL_CHECK(glUniform4fv(predefined.m_loc
									, 1
									, &rect[0]
								) );
							}
							break;

						case PredefinedUniform::View:
							{
								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, m_render->m_view[view].val
									) );
							}
							break;

						case PredefinedUniform::ViewProj:
							{
								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, viewProj[view].val
									) );
							}
							break;

						case PredefinedUniform::Model:
							{
								const Matrix4& model = m_render->m_matrixCache.m_cache[state.m_matrix];
								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, bx::uint32_min(predefined.m_count, state.m_num)
									, GL_FALSE
									, model.val
									) );
							}
							break;

						case PredefinedUniform::ModelView:
							{
								Matrix4 modelView;
								const Matrix4& model = m_render->m_matrixCache.m_cache[state.m_matrix];
								mtxMul(modelView.val, model.val, m_render->m_view[view].val);

								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, modelView.val
									) );
							}
							break;

						case PredefinedUniform::ModelViewProj:
							{
								Matrix4 modelViewProj;
								const Matrix4& model = m_render->m_matrixCache.m_cache[state.m_matrix];
								mtxMul(modelViewProj.val, model.val, viewProj[view].val);

								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, modelViewProj.val
									) );
							}
							break;

						case PredefinedUniform::ModelViewProjX:
							{
								const Matrix4& model = m_render->m_matrixCache.m_cache[state.m_matrix];

								static const BX_ALIGN_STRUCT_16(float) s_bias[16] =
								{
									0.5f, 0.0f, 0.0f, 0.0f,
									0.0f, 0.5f, 0.0f, 0.0f,
									0.0f, 0.0f, 0.5f, 0.0f,
									0.5f, 0.5f, 0.5f, 1.0f,
								};

								uint8_t other = m_render->m_other[view];
								Matrix4 viewProjBias;
								mtxMul(viewProjBias.val, viewProj[other].val, s_bias);

								Matrix4 modelViewProj;
								mtxMul(modelViewProj.val, model.val, viewProjBias.val);

								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, modelViewProj.val
									) );
							}
							break;

						case PredefinedUniform::ViewProjX:
							{
								static const BX_ALIGN_STRUCT_16(float) s_bias[16] =
								{
									0.5f, 0.0f, 0.0f, 0.0f,
									0.0f, 0.5f, 0.0f, 0.0f,
									0.0f, 0.0f, 0.5f, 0.0f,
									0.5f, 0.5f, 0.5f, 1.0f,
								};

								uint8_t other = m_render->m_other[view];
								Matrix4 viewProjBias;
								mtxMul(viewProjBias.val, viewProj[other].val, s_bias);

								GL_CHECK(glUniformMatrix4fv(predefined.m_loc
									, 1
									, GL_FALSE
									, viewProjBias.val
									) );
							}
							break;

						case PredefinedUniform::AlphaRef:
							{
								GL_CHECK(glUniform1f(predefined.m_loc, alphaRef) );
							}
							break;

						case PredefinedUniform::Count:
							break;
						}
					}

//						if (BGFX_STATE_TEX_MASK & changedFlags)
					{
						uint64_t flag = BGFX_STATE_TEX0;
						for (uint32_t stage = 0; stage < BGFX_STATE_TEX_COUNT; ++stage)
						{
							const Sampler& sampler = state.m_sampler[stage];
							Sampler& current = currentState.m_sampler[stage];
							if (current.m_idx != sampler.m_idx
							||  current.m_flags != sampler.m_flags
							||  programChanged)
							{
								if (invalidHandle != sampler.m_idx)
								{
									switch (sampler.m_flags&BGFX_SAMPLER_TYPE_MASK)
									{
									case BGFX_SAMPLER_TEXTURE:
										{
											Texture& texture = s_renderCtx->m_textures[sampler.m_idx];
											texture.commit(stage, sampler.m_flags);
										}
										break;

									case BGFX_SAMPLER_RENDERTARGET_COLOR:
										{
											RenderTarget& rt = s_renderCtx->m_renderTargets[sampler.m_idx];
											rt.m_color.commit(stage, sampler.m_flags);
										}
										break;

									case BGFX_SAMPLER_RENDERTARGET_DEPTH:
										{
											RenderTarget& rt = s_renderCtx->m_renderTargets[sampler.m_idx];
											rt.m_depth.commit(stage, sampler.m_flags);
										}
										break;
									}
								}
							}

							current = sampler;
							flag <<= 1;
						}
					}

					if (0 != defaultVao
					&&  0 == state.m_startVertex
					&&  0 == state.m_instanceDataOffset)
					{
						if (programChanged
						||  currentState.m_vertexBuffer.idx != state.m_vertexBuffer.idx
						||  currentState.m_indexBuffer.idx != state.m_indexBuffer.idx
						||  currentState.m_instanceDataBuffer.idx != state.m_instanceDataBuffer.idx
						||  currentState.m_instanceDataOffset != state.m_instanceDataOffset
						||  currentState.m_instanceDataStride != state.m_instanceDataStride)
						{
							bx::HashMurmur2A murmur;
							murmur.begin();
							murmur.add(state.m_vertexBuffer.idx);
							murmur.add(state.m_indexBuffer.idx);
							murmur.add(state.m_instanceDataBuffer.idx);
							murmur.add(state.m_instanceDataOffset);
							murmur.add(state.m_instanceDataStride);
							murmur.add(programIdx);
							uint32_t hash = murmur.end();

							currentState.m_vertexBuffer = state.m_vertexBuffer;
							currentState.m_indexBuffer = state.m_indexBuffer;
							currentState.m_instanceDataOffset = state.m_instanceDataOffset;
							currentState.m_instanceDataStride = state.m_instanceDataStride;
							baseVertex = state.m_startVertex;

							GLuint id = s_renderCtx->m_vaoStateCache.find(hash);
							if (UINT32_MAX != id)
							{
								currentVao = id;
								GL_CHECK(glBindVertexArray(id) );
							}
							else
							{
								id = s_renderCtx->m_vaoStateCache.add(hash);
								currentVao = id;
								GL_CHECK(glBindVertexArray(id) );

								Program& program = s_renderCtx->m_program[programIdx];
								program.add(hash);

								if (isValid(state.m_vertexBuffer) )
								{
									VertexBuffer& vb = s_renderCtx->m_vertexBuffers[state.m_vertexBuffer.idx];
									vb.add(hash);
									GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, vb.m_id) );

									uint16_t decl = !isValid(vb.m_decl) ? state.m_vertexDecl.idx : vb.m_decl.idx;
									program.bindAttributes(s_renderCtx->m_vertexDecls[decl], state.m_startVertex);

									if (isValid(state.m_instanceDataBuffer) )
									{
										VertexBuffer& instanceVb = s_renderCtx->m_vertexBuffers[state.m_instanceDataBuffer.idx];
										instanceVb.add(hash);
										GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, instanceVb.m_id) );
										program.bindInstanceData(state.m_instanceDataStride, state.m_instanceDataOffset);
									}
								}
								else
								{
									GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, 0) );
								}

								if (isValid(state.m_indexBuffer) )
								{
									IndexBuffer& ib = s_renderCtx->m_indexBuffers[state.m_indexBuffer.idx];
									ib.add(hash);
									GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ib.m_id) );
								}
								else
								{
									GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0) );
								}
							}
						}
					}
					else
					{
						if (0 != defaultVao
						&&  0 != currentVao)
						{
							GL_CHECK(glBindVertexArray(defaultVao) );
							currentState.m_vertexBuffer.idx = invalidHandle;
							currentState.m_indexBuffer.idx = invalidHandle;
							bindAttribs = true;
							currentVao = 0;
						}

						if (programChanged
						||  currentState.m_vertexBuffer.idx != state.m_vertexBuffer.idx
						||  currentState.m_instanceDataBuffer.idx != state.m_instanceDataBuffer.idx
						||  currentState.m_instanceDataOffset != state.m_instanceDataOffset
						||  currentState.m_instanceDataStride != state.m_instanceDataStride)
						{
							currentState.m_vertexBuffer = state.m_vertexBuffer;
							currentState.m_instanceDataBuffer.idx = state.m_instanceDataBuffer.idx;
							currentState.m_instanceDataOffset = state.m_instanceDataOffset;
							currentState.m_instanceDataStride = state.m_instanceDataStride;

							uint16_t handle = state.m_vertexBuffer.idx;
							if (invalidHandle != handle)
							{
								VertexBuffer& vb = s_renderCtx->m_vertexBuffers[handle];
								GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, vb.m_id) );
								bindAttribs = true;
							}
							else
							{
								GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, 0) );
							}
						}

						if (currentState.m_indexBuffer.idx != state.m_indexBuffer.idx)
						{
							currentState.m_indexBuffer = state.m_indexBuffer;

							uint16_t handle = state.m_indexBuffer.idx;
							if (invalidHandle != handle)
							{
								IndexBuffer& ib = s_renderCtx->m_indexBuffers[handle];
								GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ib.m_id) );
							}
							else
							{
								GL_CHECK(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0) );
							}
						}

						if (isValid(currentState.m_vertexBuffer) )
						{
							if (baseVertex != state.m_startVertex
							||  bindAttribs)
							{
								baseVertex = state.m_startVertex;
								const VertexBuffer& vb = s_renderCtx->m_vertexBuffers[state.m_vertexBuffer.idx];
								uint16_t decl = !isValid(vb.m_decl) ? state.m_vertexDecl.idx : vb.m_decl.idx;
								const Program& program = s_renderCtx->m_program[programIdx];
								program.bindAttributes(s_renderCtx->m_vertexDecls[decl], state.m_startVertex);

								if (isValid(state.m_instanceDataBuffer) )
								{
									GL_CHECK(glBindBuffer(GL_ARRAY_BUFFER, s_renderCtx->m_vertexBuffers[state.m_instanceDataBuffer.idx].m_id) );
									program.bindInstanceData(state.m_instanceDataStride, state.m_instanceDataOffset);
								}
							}
						}
					}

					if (isValid(currentState.m_vertexBuffer) )
					{
						uint32_t numVertices = state.m_numVertices;
						if (UINT32_MAX == numVertices)
						{
							const VertexBuffer& vb = s_renderCtx->m_vertexBuffers[currentState.m_vertexBuffer.idx];
							uint16_t decl = !isValid(vb.m_decl) ? state.m_vertexDecl.idx : vb.m_decl.idx;
							const VertexDecl& vertexDecl = s_renderCtx->m_vertexDecls[decl];
							numVertices = vb.m_size/vertexDecl.m_stride;
						}

						uint32_t numIndices = 0;
						uint32_t numPrimsSubmitted = 0;
						uint32_t numInstances = 0;
						uint32_t numPrimsRendered = 0;

						if (isValid(state.m_indexBuffer) )
						{
							if (UINT32_MAX == state.m_numIndices)
							{
								numIndices = s_renderCtx->m_indexBuffers[state.m_indexBuffer.idx].m_size/2;
								numPrimsSubmitted = numIndices/primNumVerts;
								numInstances = state.m_numInstances;
								numPrimsRendered = numPrimsSubmitted*state.m_numInstances;

								GL_CHECK(s_drawElementsInstanced(primType
									, numIndices
									, GL_UNSIGNED_SHORT
									, (void*)0
									, state.m_numInstances
									) );
							}
							else if (primNumVerts <= state.m_numIndices)
							{
								numIndices = state.m_numIndices;
								numPrimsSubmitted = numIndices/primNumVerts;
								numInstances = state.m_numInstances;
								numPrimsRendered = numPrimsSubmitted*state.m_numInstances;

								GL_CHECK(s_drawElementsInstanced(primType
									, numIndices
									, GL_UNSIGNED_SHORT
									, (void*)(uintptr_t)(state.m_startIndex*2)
									, state.m_numInstances
									) );
							}
						}
						else
						{
							numPrimsSubmitted = numVertices/primNumVerts;
							numInstances = state.m_numInstances;
							numPrimsRendered = numPrimsSubmitted*state.m_numInstances;

							GL_CHECK(s_drawArraysInstanced(primType
								, 0
								, numVertices
								, state.m_numInstances
								) );
						}

						statsNumPrimsSubmitted += numPrimsSubmitted;
						statsNumIndices += numIndices;
						statsNumInstances += numInstances;
						statsNumPrimsRendered += numPrimsRendered;
					}
				}
			}

			s_renderCtx->blitMsaaFbo();

			if (0 < m_render->m_num)
			{
				captureElapsed = -bx::getHPCounter();
				s_renderCtx->capture();
				captureElapsed += bx::getHPCounter();
			}
		}

		int64_t now = bx::getHPCounter();
		elapsed += now;

		static int64_t last = now;
		int64_t frameTime = now - last;
		last = now;

		static int64_t min = frameTime;
		static int64_t max = frameTime;
		min = min > frameTime ? frameTime : min;
		max = max < frameTime ? frameTime : max;

		if (m_render->m_debug & (BGFX_DEBUG_IFH|BGFX_DEBUG_STATS) )
		{
			double elapsedGpuMs = 0.0;
#if BGFX_CONFIG_RENDERER_OPENGL
			s_renderCtx->m_queries.end(GL_TIME_ELAPSED);
			uint64_t elapsedGl = s_renderCtx->m_queries.getResult(0);
			elapsedGpuMs = double(elapsedGl)/1e6;
#endif // BGFX_CONFIG_RENDERER_OPENGL

			TextVideoMem& tvm = s_renderCtx->m_textVideoMem;

			static int64_t next = now;

			if (now >= next)
			{
				next = now + bx::getHPFrequency();
				double freq = double(bx::getHPFrequency() );
				double toMs = 1000.0/freq;

				tvm.clear();
				uint16_t pos = 0;
				tvm.printf(0, pos++, BGFX_CONFIG_DEBUG ? 0x89 : 0x8f, " " BGFX_RENDERER_NAME " ");
				tvm.printf(0, pos++, 0x0f, "      Vendor: %s", s_renderCtx->m_vendor);
				tvm.printf(0, pos++, 0x0f, "    Renderer: %s", s_renderCtx->m_renderer);
				tvm.printf(0, pos++, 0x0f, "     Version: %s", s_renderCtx->m_version);
				tvm.printf(0, pos++, 0x0f, "GLSL version: %s", s_renderCtx->m_glslVersion);

				pos = 10;
				tvm.printf(10, pos++, 0x8e, "  Frame CPU: %7.3f, % 7.3f \x1f, % 7.3f \x1e [ms] / % 6.2f FPS%s"
					, double(frameTime)*toMs
					, double(min)*toMs
					, double(max)*toMs
					, freq/frameTime
					, !!(m_resolution.m_flags&BGFX_RESET_VSYNC) ? " (vsync)" : ""
					);

				double elapsedCpuMs = double(elapsed)*toMs;
				tvm.printf(10, pos++, 0x8e, " Draw calls: %4d / CPU %3.4f [ms] %c GPU %3.4f [ms]"
					, m_render->m_num
					, elapsedCpuMs
					, elapsedCpuMs > elapsedGpuMs ? '>' : '<'
					, elapsedGpuMs
					);
				tvm.printf(10, pos++, 0x8e, "      Prims: %7d (#inst: %5d), submitted: %7d"
					, statsNumPrimsRendered
					, statsNumInstances
					, statsNumPrimsSubmitted
					);

				double captureMs = double(captureElapsed)*toMs;
				tvm.printf(10, pos++, 0x8e, "    Capture: %3.4f [ms]", captureMs);

				tvm.printf(10, pos++, 0x8e, "    Indices: %7d", statsNumIndices);
				tvm.printf(10, pos++, 0x8e, "   DVB size: %7d", m_render->m_vboffset);
				tvm.printf(10, pos++, 0x8e, "   DIB size: %7d", m_render->m_iboffset);

#if BGFX_CONFIG_RENDERER_OPENGL
				if (s_extension[Extension::ATI_meminfo].m_supported)
				{
					GLint vboFree[4];
					GL_CHECK(glGetIntegerv(GL_VBO_FREE_MEMORY_ATI, vboFree) );

					GLint texFree[4];
					GL_CHECK(glGetIntegerv(GL_TEXTURE_FREE_MEMORY_ATI, texFree) );

					GLint rbfFree[4];
					GL_CHECK(glGetIntegerv(GL_RENDERBUFFER_FREE_MEMORY_ATI, rbfFree) );

					pos++;
					tvm.printf(10, pos++, 0x8c, " -------------|    free|  free b|     aux|  aux fb");
					tvm.printf(10, pos++, 0x8e, "           VBO: %7d, %7d, %7d, %7d", vboFree[0], vboFree[1], vboFree[2], vboFree[3]);
					tvm.printf(10, pos++, 0x8e, "       Texture: %7d, %7d, %7d, %7d", texFree[0], texFree[1], texFree[2], texFree[3]);
					tvm.printf(10, pos++, 0x8e, " Render Buffer: %7d, %7d, %7d, %7d", rbfFree[0], rbfFree[1], rbfFree[2], rbfFree[3]);
				}
				else if (s_extension[Extension::NVX_gpu_memory_info].m_supported)
				{
					GLint dedicated;
					GL_CHECK(glGetIntegerv(GL_GPU_MEMORY_INFO_DEDICATED_VIDMEM_NVX, &dedicated) );

					GLint totalAvail;
					GL_CHECK(glGetIntegerv(GL_GPU_MEMORY_INFO_TOTAL_AVAILABLE_MEMORY_NVX, &totalAvail) );

					GLint currAvail;
					GL_CHECK(glGetIntegerv(GL_GPU_MEMORY_INFO_CURRENT_AVAILABLE_VIDMEM_NVX, &currAvail) );

					GLint evictedCount;
					GL_CHECK(glGetIntegerv(GL_GPU_MEMORY_INFO_EVICTION_COUNT_NVX, &evictedCount) );

					GLint evictedMemory;
					GL_CHECK(glGetIntegerv(GL_GPU_MEMORY_INFO_EVICTED_MEMORY_NVX, &evictedMemory) );

					pos++;
					tvm.printf(10, pos++, 0x8c, "----------|");
					tvm.printf(10, pos++, 0x8e, " Dedicated: %7d", dedicated);
					tvm.printf(10, pos++, 0x8e, " Available: %7d (%7d)", currAvail, totalAvail);
					tvm.printf(10, pos++, 0x8e, "  Eviction: %7d / %7d", evictedCount, evictedMemory);
				}
#endif // BGFX_CONFIG_RENDERER_OPENGL

				uint8_t attr[2] = { 0x89, 0x8a };
				uint8_t attrIndex = m_render->m_waitSubmit < m_render->m_waitRender;

				pos++;
				tvm.printf(10, pos++, attr[attrIndex&1], "Submit wait: %3.4f [ms]", double(m_render->m_waitSubmit)*toMs);
				tvm.printf(10, pos++, attr[(attrIndex+1)&1], "Render wait: %3.4f [ms]", double(m_render->m_waitRender)*toMs);

				min = frameTime;
				max = frameTime;
			}

			m_textVideoMemBlitter.blit(tvm);
		}
		else if (m_render->m_debug & BGFX_DEBUG_TEXT)
		{
			m_textVideoMemBlitter.blit(m_render->m_textVideoMem);
		}

		GREMEDY_FRAMETERMINATOR();
	}
}

#endif // (BGFX_CONFIG_RENDERER_OPENGLES2|BGFX_CONFIG_RENDERER_OPENGLES3|BGFX_CONFIG_RENDERER_OPENGL)