Added BGFX_RESET_DEPTH_CLAMP. Issue #598.

include/bgfx/bgfxdefines.h

@@ -354,6 +354,7 @@
 #define BGFX_RESET_FLIP_AFTER_RENDER     UINT32_C(0x00004000) //!< This flag  specifies where flip occurs. Default behavior is that flip occurs before rendering new frame. This flag only has effect when `BGFX_CONFIG_MULTITHREADED=0`.
 #define BGFX_RESET_SRGB_BACKBUFFER       UINT32_C(0x00008000) //!< Enable sRGB backbuffer.
 #define BGFX_RESET_HIDPI                 UINT32_C(0x00010000) //!< Enable HiDPI rendering.
+#define BGFX_RESET_DEPTH_CLAMP           UINT32_C(0x00020000) //!< Enable depth clamp.
 
 #define BGFX_RESET_RESERVED_SHIFT        31                   //!< Internal bits shift.
 #define BGFX_RESET_RESERVED_MASK         UINT32_C(0x80000000) //!< Internal bits mask.

src/renderer_d3d11.cpp

@@ -586,6 +586,7 @@ namespace bgfx { namespace d3d11
 			, m_captureResolve(NULL)
 			, m_wireframe(false)
 			, m_maxAnisotropy(1)
+			, m_depthClamp(false)
 			, m_currentProgram(NULL)
 			, m_vsChanges(0)
 			, m_fsChanges(0)
@@ -2166,19 +2167,34 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 		{
 			bool recenter   = !!(_resolution.m_flags & BGFX_RESET_HMD_RECENTER);
 
+			uint32_t maxAnisotropy = 1;
 			if (!!(_resolution.m_flags & BGFX_RESET_MAXANISOTROPY) )
 			{
-				m_maxAnisotropy = (m_featureLevel == D3D_FEATURE_LEVEL_9_1)
+				maxAnisotropy = (m_featureLevel == D3D_FEATURE_LEVEL_9_1)
 								? D3D_FL9_1_DEFAULT_MAX_ANISOTROPY
 								: D3D11_REQ_MAXANISOTROPY
 								;
 			}
-			else
+
+			if (m_maxAnisotropy != maxAnisotropy)
 			{
-				m_maxAnisotropy = 1;
+				m_maxAnisotropy = maxAnisotropy;
+				m_samplerStateCache.invalidate();
 			}
 
-			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY);
+			bool depthClamp = false;
+			if (!!(_resolution.m_flags & BGFX_RESET_DEPTH_CLAMP) )
+			{
+				depthClamp = m_featureLevel <= D3D_FEATURE_LEVEL_9_3; // disabling depth clamp is only supported on 10_0+
+			}
+
+			if (m_depthClamp != depthClamp)
+			{
+				m_depthClamp = depthClamp;
+				m_rasterizerStateCache.invalidate();
+			}
+
+			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY | BGFX_RESET_DEPTH_CLAMP);
 
 			if (m_resolution.m_width  != _resolution.m_width
 			||  m_resolution.m_height != _resolution.m_height
@@ -2657,7 +2673,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 				desc.DepthBias = 0;
 				desc.DepthBiasClamp = 0.0f;
 				desc.SlopeScaledDepthBias = 0.0f;
-				desc.DepthClipEnable = m_featureLevel <= D3D_FEATURE_LEVEL_9_3;	// disabling depth clip is only supported on 10_0+
+				desc.DepthClipEnable = m_depthClamp;
 				desc.ScissorEnable = _scissor;
 				desc.MultisampleEnable = !!(_state&BGFX_STATE_MSAA);
 				desc.AntialiasedLineEnable = false;
@@ -3340,6 +3356,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 
 		SwapChainDesc m_scd;
 		uint32_t m_maxAnisotropy;
+		bool m_depthClamp;
 
 		IndexBufferD3D11 m_indexBuffers[BGFX_CONFIG_MAX_INDEX_BUFFERS];
 		VertexBufferD3D11 m_vertexBuffers[BGFX_CONFIG_MAX_VERTEX_BUFFERS];

src/renderer_d3d12.cpp

@@ -459,6 +459,7 @@ namespace bgfx { namespace d3d12
 		RendererContextD3D12()
 			: m_wireframe(false)
 			, m_maxAnisotropy(1)
+			, m_depthClamp(false)
 			, m_fsChanges(0)
 			, m_vsChanges(0)
 			, m_backBufferColorIdx(0)
@@ -1729,7 +1730,15 @@ data.NumQualityLevels = 0;
 				m_maxAnisotropy = 1;
 			}
 
-			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY);
+			bool depthClamp = !!(_resolution.m_flags & BGFX_RESET_DEPTH_CLAMP);
+
+			if (m_depthClamp != depthClamp)
+			{
+				m_depthClamp = depthClamp;
+				m_pipelineStateCache.invalidate();
+			}
+
+			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY | BGFX_RESET_DEPTH_CLAMP);
 
 			if (m_resolution.m_width  != _resolution.m_width
 			||  m_resolution.m_height != _resolution.m_height
@@ -2007,7 +2016,7 @@ data.NumQualityLevels = 0;
 			desc.DepthBias = 0;
 			desc.DepthBiasClamp = 0.0f;
 			desc.SlopeScaledDepthBias = 0.0f;
-			desc.DepthClipEnable = false;
+			desc.DepthClipEnable = m_depthClamp;
 			desc.MultisampleEnable = !!(_state&BGFX_STATE_MSAA);
 			desc.AntialiasedLineEnable = false;
 			desc.ForcedSampleCount = 0;
@@ -2636,6 +2645,7 @@ data.NumQualityLevels = 0;
 
 		DXGI_SWAP_CHAIN_DESC m_scd;
 		uint32_t m_maxAnisotropy;
+		bool m_depthClamp;
 
 		BufferD3D12 m_indexBuffers[BGFX_CONFIG_MAX_INDEX_BUFFERS];
 		VertexBufferD3D12 m_vertexBuffers[BGFX_CONFIG_MAX_VERTEX_BUFFERS];

src/renderer_gl.cpp

@@ -1936,11 +1936,6 @@ namespace bgfx { namespace gl
 				GL_CHECK(glEnable(GL_TEXTURE_CUBE_MAP_SEAMLESS) );
 			}
 
-			if (s_extension[Extension::ARB_depth_clamp].m_supported)
-			{
-				GL_CHECK(glEnable(GL_DEPTH_CLAMP) );
-			}
-
 			if (NULL == glFrameTerminatorGREMEDY
 			||  !s_extension[Extension::GREMEDY_frame_terminator].m_supported)
 			{
@@ -2404,7 +2399,20 @@ namespace bgfx { namespace gl
 				? m_maxAnisotropyDefault
 				: 0.0f
 				;
-			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY);
+
+			if (s_extension[Extension::ARB_depth_clamp].m_supported)
+			{
+				if (!!(_resolution.m_flags & BGFX_RESET_DEPTH_CLAMP) )
+				{
+					GL_CHECK(glEnable(GL_DEPTH_CLAMP) );
+				}
+				else
+				{
+					GL_CHECK(glDisable(GL_DEPTH_CLAMP) );
+				}
+			}
+
+			uint32_t flags = _resolution.m_flags & ~(BGFX_RESET_HMD_RECENTER | BGFX_RESET_MAXANISOTROPY | BGFX_RESET_DEPTH_CLAMP);
 
 			if (m_resolution.m_width  != _resolution.m_width
 			||  m_resolution.m_height != _resolution.m_height