Added ability to read occlusion query result on main thread.

examples/26-occlusion/occlusion.cpp

@@ -212,6 +212,8 @@ class Occlusion : public entry::AppI
 			bgfx::touch(0);
 			bgfx::touch(2);
 
+			uint8_t img[CUBES_DIM*CUBES_DIM*2];
+
 			for (uint32_t yy = 0; yy < CUBES_DIM; ++yy)
 			{
 				for (uint32_t xx = 0; xx < CUBES_DIM; ++xx)
@@ -246,9 +248,14 @@ class Occlusion : public entry::AppI
 					bgfx::setCondition(occlusionQuery, true);
 					bgfx::setState(BGFX_STATE_DEFAULT);
 					bgfx::submit(2, m_program);
+
+					img[(yy*CUBES_DIM+xx)*2+0] = " \xfex"[bgfx::getResult(occlusionQuery)];
+					img[(yy*CUBES_DIM+xx)*2+1] = 0xf;
 				}
 			}
 
+			bgfx::dbgTextImage(5, 5, CUBES_DIM, CUBES_DIM, img, CUBES_DIM*2);
+
 			// Advance to next frame. Rendering thread will be kicked to
 			// process submitted rendering primitives.
 			bgfx::frame();

include/bgfx/bgfx.h

@@ -275,6 +275,18 @@ namespace bgfx
 		};
 	};
 
+	struct OcclusionQueryResult
+	{
+		enum Enum
+		{
+			Invisible,
+			Visible,
+			NoResult,
+
+			Count
+		};
+	};
+
 	static const uint16_t invalidHandle = UINT16_MAX;
 
 	BGFX_HANDLE(DynamicIndexBufferHandle);
@@ -1538,6 +1550,14 @@ namespace bgfx
 	///
 	OcclusionQueryHandle createOcclusionQuery();
 
+	/// Retrieve occlusion query result.
+	///
+	/// @param[in] _handle Handle to occlusion query object.
+	///
+	/// @attention C99 equivalent is `bgfx_get_result`.
+	///
+	OcclusionQueryResult::Enum getResult(OcclusionQueryHandle _handle);
+
 	/// Destroy occlusion query.
 	///
 	/// @param[in] _handle Handle to occlusion query object.

include/bgfx/c99/bgfx.h

@@ -184,6 +184,16 @@ typedef enum bgfx_backbuffer_ratio
 
 } bgfx_backbuffer_ratio_t;
 
+typedef enum bgfx_occlusion_query_result
+{
+    BGFX_OCCLUSION_QUERY_RESULT_INVISIBLE,
+    BGFX_OCCLUSION_QUERY_RESULT_VISIBLE,
+    BGFX_OCCLUSION_QUERY_RESULT_NORESULT,
+
+    BGFX_OCCLUSION_QUERY_RESULT_COUNT
+
+} bgfx_occlusion_query_result_t;
+
 #define BGFX_HANDLE_T(_name) \
     typedef struct _name { uint16_t idx; } _name##_t
 
@@ -642,6 +652,9 @@ BGFX_C_API void bgfx_destroy_uniform(bgfx_uniform_handle_t _handle);
 /**/
 BGFX_C_API bgfx_occlusion_query_handle_t bgfx_create_occlusion_query();
 
+/**/
+BGFX_C_API bgfx_occlusion_query_result_t bgfx_get_result(bgfx_occlusion_query_handle_t _handle);
+
 /**/
 BGFX_C_API void bgfx_destroy_occlusion_query(bgfx_occlusion_query_handle_t _handle);
 

src/bgfx.cpp

@@ -1372,6 +1372,8 @@ namespace bgfx
 
 		bx::xchg(m_render, m_submit);
 
+		memcpy(m_render->m_occlusion, m_submit->m_occlusion, sizeof(m_submit->m_occlusion) );
+
 		if (!BX_ENABLED(BGFX_CONFIG_MULTITHREADED)
 		||  m_singleThreaded)
 		{
@@ -3026,6 +3028,13 @@ again:
 		return s_ctx->createOcclusionQuery();
 	}
 
+	OcclusionQueryResult::Enum getResult(OcclusionQueryHandle _handle)
+	{
+		BGFX_CHECK_MAIN_THREAD();
+		BGFX_CHECK_CAPS(BGFX_CAPS_OCCLUSION_QUERY, "Occlusion query is not supported!");
+		return s_ctx->getResult(_handle);
+	}
+
 	void destroyOcclusionQuery(OcclusionQueryHandle _handle)
 	{
 		BGFX_CHECK_MAIN_THREAD();
@@ -3991,6 +4000,12 @@ BGFX_C_API bgfx_occlusion_query_handle_t bgfx_create_occlusion_query()
 	return handle.c;
 }
 
+BGFX_C_API bgfx_occlusion_query_result_t bgfx_get_result(bgfx_occlusion_query_handle_t _handle)
+{
+	union { bgfx_occlusion_query_handle_t c; bgfx::OcclusionQueryHandle cpp; } handle = { _handle };
+	return bgfx_occlusion_query_result_t(bgfx::getResult(handle.cpp) );
+}
+
 BGFX_C_API void bgfx_destroy_occlusion_query(bgfx_occlusion_query_handle_t _handle)
 {
 	union { bgfx_occlusion_query_handle_t c; bgfx::OcclusionQueryHandle cpp; } handle = { _handle };

src/bgfx_p.h

@@ -1292,6 +1292,7 @@ namespace bgfx
 			term.m_program = invalidHandle;
 			m_sortKeys[BGFX_CONFIG_MAX_DRAW_CALLS]   = term.encodeDraw();
 			m_sortValues[BGFX_CONFIG_MAX_DRAW_CALLS] = BGFX_CONFIG_MAX_DRAW_CALLS;
+			memset(m_occlusion, 0xff, sizeof(m_occlusion) );
 		}
 
 		~Frame()
@@ -1681,6 +1682,7 @@ namespace bgfx
 		Matrix4 m_view[BGFX_CONFIG_MAX_VIEWS];
 		Matrix4 m_proj[2][BGFX_CONFIG_MAX_VIEWS];
 		uint8_t m_viewFlags[BGFX_CONFIG_MAX_VIEWS];
+		uint8_t m_occlusion[BGFX_CONFIG_MAX_OCCUSION_QUERIES];
 
 		uint64_t m_sortKeys[BGFX_CONFIG_MAX_DRAW_CALLS+1];
 		RenderItemCount m_sortValues[BGFX_CONFIG_MAX_DRAW_CALLS+1];
@@ -3297,9 +3299,27 @@ namespace bgfx
 		BGFX_API_FUNC(OcclusionQueryHandle createOcclusionQuery() )
 		{
 			OcclusionQueryHandle handle = { m_occlusionQueryHandle.alloc() };
+			if (isValid(handle) )
+			{
+				m_submit->m_occlusion[handle.idx] = UINT8_MAX;
+			}
 			return handle;
 		}
 
+		BGFX_API_FUNC(OcclusionQueryResult::Enum getResult(OcclusionQueryHandle _handle) )
+		{
+			BGFX_CHECK_HANDLE("destroyOcclusionQuery", m_occlusionQueryHandle, _handle);
+
+			switch (m_submit->m_occlusion[_handle.idx])
+			{
+			case 0:         return OcclusionQueryResult::Invisible;
+			case UINT8_MAX: return OcclusionQueryResult::NoResult;
+			default:;
+			}
+
+			return OcclusionQueryResult::Visible;
+		}
+
 		BGFX_API_FUNC(void destroyOcclusionQuery(OcclusionQueryHandle _handle) )
 		{
 			BGFX_CHECK_HANDLE("destroyOcclusionQuery", m_occlusionQueryHandle, _handle);

src/renderer_d3d11.cpp

@@ -2729,10 +2729,10 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 			return sampler;
 		}
 
-		bool isVisible(OcclusionQueryHandle _handle, bool _visible)
+		bool isVisible(Frame* _render, OcclusionQueryHandle _handle, bool _visible)
 		{
-			m_occlusionQuery.resolve();
+			m_occlusionQuery.resolve(_render);
-			return _visible == m_occlusion[_handle.idx];
+			return _visible == 0 != _render->m_occlusion[_handle.idx];
 		}
 
 		DXGI_FORMAT getBufferFormat()
@@ -3334,7 +3334,6 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 		TextureD3D11 m_textures[BGFX_CONFIG_MAX_TEXTURES];
 		VertexDecl m_vertexDecls[BGFX_CONFIG_MAX_VERTEX_DECLS];
 		FrameBufferD3D11 m_frameBuffers[BGFX_CONFIG_MAX_FRAME_BUFFERS];
-		bool m_occlusion[BGFX_CONFIG_MAX_OCCUSION_QUERIES];
 		void* m_uniforms[BGFX_CONFIG_MAX_UNIFORMS];
 		Matrix4 m_predefinedUniforms[PredefinedUniform::Count];
 		UniformRegistry m_uniformReg;
@@ -4577,11 +4576,11 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 		}
 	}
 
-	void OcclusionQueryD3D11::begin(OcclusionQueryHandle _handle)
+	void OcclusionQueryD3D11::begin(Frame* _render, OcclusionQueryHandle _handle)
 	{
 		while (0 == m_control.reserve(1) )
 		{
-			resolve(true);
+			resolve(_render, true);
 		}
 
 		ID3D11DeviceContext* deviceCtx = s_renderD3D11->m_deviceCtx;
@@ -4598,7 +4597,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 		m_control.commit(1);
 	}
 
-	void OcclusionQueryD3D11::resolve(bool _wait)
+	void OcclusionQueryD3D11::resolve(Frame* _render, bool _wait)
 	{
 		ID3D11DeviceContext* deviceCtx = s_renderD3D11->m_deviceCtx;
 
@@ -4613,7 +4612,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 				break;
 			}
 
-			s_renderD3D11->m_occlusion[query.m_handle.idx] = 0 < result;
+			_render->m_occlusion[query.m_handle.idx] = 0 < result;
 			m_control.consume(1);
 		}
 	}
@@ -4687,7 +4686,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 		uint32_t statsNumIndices = 0;
 		uint32_t statsKeyType[2] = {};
 
-		m_occlusionQuery.resolve();
+		m_occlusionQuery.resolve(_render);
 
 		if (0 == (_render->m_debug&BGFX_DEBUG_IFH) )
 		{
@@ -5053,7 +5052,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 				const bool hasOcclusionQuery = 0 != (draw.m_stateFlags & BGFX_STATE_INTERNAL_OCCLUSION_QUERY);
 				if (isValid(draw.m_occlusionQuery)
 				&&  !hasOcclusionQuery
-				&&  !isVisible(draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
+				&&  !isVisible(_render, draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
 				{
 					continue;
 				}
@@ -5348,7 +5347,7 @@ BX_PRAGMA_DIAGNOSTIC_POP();
 
 					if (hasOcclusionQuery)
 					{
-						m_occlusionQuery.begin(draw.m_occlusionQuery);
+						m_occlusionQuery.begin(_render, draw.m_occlusionQuery);
 					}
 
 					if (isValid(draw.m_indirectBuffer) )

src/renderer_d3d11.h

@@ -316,9 +316,9 @@ namespace bgfx { namespace d3d11
 
 		void postReset();
 		void preReset();
-		void begin(OcclusionQueryHandle _handle);
+		void begin(Frame* _render, OcclusionQueryHandle _handle);
 		void end();
-		void resolve(bool _wait = false);
+		void resolve(Frame* _render, bool _wait = false);
 
 		struct Query
 		{

src/renderer_d3d9.cpp

@@ -1565,10 +1565,10 @@ namespace bgfx { namespace d3d9
 			}
 		}
 
-		bool isVisible(OcclusionQueryHandle _handle, bool _visible)
+		bool isVisible(Frame* _render, OcclusionQueryHandle _handle, bool _visible)
 		{
-			m_occlusionQuery.resolve();
+			m_occlusionQuery.resolve(_render);
-			return _visible == m_occlusion[_handle.idx];
+			return _visible == 0 != _render->m_occlusion[_handle.idx];
 		}
 
 		void capturePreReset()
@@ -2007,7 +2007,6 @@ namespace bgfx { namespace d3d9
 		TextureD3D9 m_textures[BGFX_CONFIG_MAX_TEXTURES];
 		VertexDeclD3D9 m_vertexDecls[BGFX_CONFIG_MAX_VERTEX_DECLS];
 		FrameBufferD3D9 m_frameBuffers[BGFX_CONFIG_MAX_FRAME_BUFFERS];
-		bool m_occlusion[BGFX_CONFIG_MAX_OCCUSION_QUERIES];
 		UniformRegistry m_uniformReg;
 		void* m_uniforms[BGFX_CONFIG_MAX_UNIFORMS];
 
@@ -3410,11 +3409,11 @@ namespace bgfx { namespace d3d9
 		}
 	}
 
-	void OcclusionQueryD3D9::begin(OcclusionQueryHandle _handle)
+	void OcclusionQueryD3D9::begin(Frame* _render, OcclusionQueryHandle _handle)
 	{
 		while (0 == m_control.reserve(1) )
 		{
-			resolve(true);
+			resolve(_render, true);
 		}
 
 		Query& query = m_query[m_control.m_current];
@@ -3429,7 +3428,7 @@ namespace bgfx { namespace d3d9
 		m_control.commit(1);
 	}
 
-	void OcclusionQueryD3D9::resolve(bool)
+	void OcclusionQueryD3D9::resolve(Frame* _render, bool)
 	{
 		while (0 != m_control.available() )
 		{
@@ -3442,7 +3441,7 @@ namespace bgfx { namespace d3d9
 				break;
 			}
 
-			s_renderD3D9->m_occlusion[query.m_handle.idx] = 0 < result;
+			_render->m_occlusion[query.m_handle.idx] = 0 < result;
 			m_control.consume(1);
 		}
 	}
@@ -3518,7 +3517,7 @@ namespace bgfx { namespace d3d9
 
 		if (m_occlusionQuerySupport)
 		{
-			m_occlusionQuery.resolve();
+			m_occlusionQuery.resolve(_render);
 		}
 
 		if (0 == (_render->m_debug&BGFX_DEBUG_IFH) )
@@ -3539,7 +3538,7 @@ namespace bgfx { namespace d3d9
 				const bool hasOcclusionQuery = 0 != (draw.m_stateFlags & BGFX_STATE_INTERNAL_OCCLUSION_QUERY);
 				if (isValid(draw.m_occlusionQuery)
 				&&  !hasOcclusionQuery
-				&&  !isVisible(draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
+				&&  !isVisible(_render, draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
 				{
 					continue;
 				}
@@ -4003,7 +4002,7 @@ namespace bgfx { namespace d3d9
 
 					if (hasOcclusionQuery)
 					{
-						m_occlusionQuery.begin(draw.m_occlusionQuery);
+						m_occlusionQuery.begin(_render, draw.m_occlusionQuery);
 					}
 
 					if (isValid(draw.m_indexBuffer) )

src/renderer_d3d9.h

@@ -439,9 +439,9 @@ namespace bgfx { namespace d3d9
 
 		void postReset();
 		void preReset();
-		void begin(OcclusionQueryHandle _handle);
+		void begin(Frame* _render, OcclusionQueryHandle _handle);
 		void end();
-		void resolve(bool _wait = false);
+		void resolve(Frame* _render, bool _wait = false);
 
 		struct Query
 		{

src/renderer_gl.cpp

@@ -2712,10 +2712,10 @@ namespace bgfx { namespace gl
 			}
 		}
 
-		bool isVisible(OcclusionQueryHandle _handle, bool _visible)
+		bool isVisible(Frame* _render, OcclusionQueryHandle _handle, bool _visible)
 		{
-			m_occlusionQuery.resolve();
+			m_occlusionQuery.resolve(_render);
-			return _visible == m_occlusion[_handle.idx];
+			return _visible == 0 != _render->m_occlusion[_handle.idx];
 		}
 
 		void ovrPostReset()
@@ -3156,7 +3156,6 @@ namespace bgfx { namespace gl
 		TextureGL m_textures[BGFX_CONFIG_MAX_TEXTURES];
 		VertexDecl m_vertexDecls[BGFX_CONFIG_MAX_VERTEX_DECLS];
 		FrameBufferGL m_frameBuffers[BGFX_CONFIG_MAX_FRAME_BUFFERS];
-		bool m_occlusion[BGFX_CONFIG_MAX_OCCUSION_QUERIES];
 		UniformRegistry m_uniformReg;
 		void* m_uniforms[BGFX_CONFIG_MAX_UNIFORMS];
 
@@ -5166,11 +5165,11 @@ namespace bgfx { namespace gl
 		}
 	}
 
-	void OcclusionQueryGL::begin(OcclusionQueryHandle _handle)
+	void OcclusionQueryGL::begin(Frame* _render, OcclusionQueryHandle _handle)
 	{
 		while (0 == m_control.reserve(1) )
 		{
-			resolve(true);
+			resolve(_render, true);
 		}
 
 		Query& query = m_query[m_control.m_current];
@@ -5184,7 +5183,7 @@ namespace bgfx { namespace gl
 		m_control.commit(1);
 	}
 
-	void OcclusionQueryGL::resolve(bool _wait)
+	void OcclusionQueryGL::resolve(Frame* _render, bool _wait)
 	{
 		while (0 != m_control.available() )
 		{
@@ -5202,7 +5201,7 @@ namespace bgfx { namespace gl
 			}
 
 			GL_CHECK(glGetQueryObjectiv(query.m_id, GL_QUERY_RESULT, &result) );
-			s_renderGL->m_occlusion[query.m_handle.idx] = 0 < result;
+			_render->m_occlusion[query.m_handle.idx] = 0 < result;
 			m_control.consume(1);
 		}
 	}
@@ -5307,7 +5306,7 @@ namespace bgfx { namespace gl
 
 		if (m_occlusionQuerySupport)
 		{
-			m_occlusionQuery.resolve();
+			m_occlusionQuery.resolve(_render);
 		}
 
 		if (0 == (_render->m_debug&BGFX_DEBUG_IFH) )
@@ -5605,7 +5604,7 @@ namespace bgfx { namespace gl
 				const bool hasOcclusionQuery = 0 != (draw.m_stateFlags & BGFX_STATE_INTERNAL_OCCLUSION_QUERY);
 				if (isValid(draw.m_occlusionQuery)
 				&&  !hasOcclusionQuery
-				&&  !isVisible(draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
+				&&  !isVisible(_render, draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) ) )
 				{
 					continue;
 				}
@@ -6124,7 +6123,7 @@ namespace bgfx { namespace gl
 
 						if (hasOcclusionQuery)
 						{
-							m_occlusionQuery.begin(draw.m_occlusionQuery);
+							m_occlusionQuery.begin(_render, draw.m_occlusionQuery);
 						}
 
 						if (isValid(draw.m_indirectBuffer) )

src/renderer_gl.h

@@ -1270,9 +1270,9 @@ namespace bgfx { namespace gl
 
 		void create();
 		void destroy();
-		void begin(OcclusionQueryHandle _handle);
+		void begin(Frame* _render, OcclusionQueryHandle _handle);
 		void end();
-		void resolve(bool _wait = false);
+		void resolve(Frame* _render, bool _wait = false);
 
 		struct Query
 		{