Added capabilties check to examples.

examples/19-oit/oit.cpp

@@ -227,6 +227,12 @@ public:
 		m_oldHeight = 0;
 		m_oldReset  = m_reset;
 
+		m_mrtSupported = true
+			&& 2 <= caps->limits.maxFBAttachments
+			&& bgfx::isTextureValid(0, false, 1, bgfx::TextureFormat::RGBA16F, BGFX_TEXTURE_RT)
+			&& bgfx::isTextureValid(0, false, 1, bgfx::TextureFormat::R16F,    BGFX_TEXTURE_RT)
+			;
+
 		m_timeOffset = bx::getHPCounter();
 	}
 
@@ -235,7 +241,11 @@ public:
 		// Cleanup.
 		imguiDestroy();
 
-		bgfx::destroy(m_fbh);
+		if (bgfx::isValid(m_fbh) )
+		{
+			bgfx::destroy(m_fbh);
+		}
+
 		bgfx::destroy(m_ibh);
 		bgfx::destroy(m_vbh);
 		bgfx::destroy(m_blend);
@@ -257,26 +267,6 @@ public:
 	{
 		if (!entry::processEvents(m_width, m_height, m_debug, m_reset, &m_mouseState) )
 		{
-			if (m_oldWidth  != m_width
-			||  m_oldHeight != m_height
-			||  m_oldReset  != m_reset
-			||  !bgfx::isValid(m_fbh) )
-			{
-				// Recreate variable size render targets when resolution changes.
-				m_oldWidth  = m_width;
-				m_oldHeight = m_height;
-				m_oldReset  = m_reset;
-
-				if (bgfx::isValid(m_fbh) )
-				{
-					bgfx::destroy(m_fbh);
-				}
-
-				m_fbtextures[0] = bgfx::createTexture2D(uint16_t(m_width), uint16_t(m_height), false, 1, bgfx::TextureFormat::RGBA16F, BGFX_TEXTURE_RT);
-				m_fbtextures[1] = bgfx::createTexture2D(uint16_t(m_width), uint16_t(m_height), false, 1, bgfx::TextureFormat::R16F,    BGFX_TEXTURE_RT);
-				m_fbh = bgfx::createFrameBuffer(BX_COUNTOF(m_fbtextures), m_fbtextures, true);
-			}
-
 			imguiBeginFrame(m_mouseState.m_mx
 				,  m_mouseState.m_my
 				, (m_mouseState.m_buttons[entry::MouseButton::Left  ] ? IMGUI_MBUT_LEFT   : 0)
@@ -287,196 +277,224 @@ public:
 				, uint16_t(m_height)
 				);
 
-			showExampleDialog(this);
-
-			ImGui::SetNextWindowPos(
-				  ImVec2(m_width - m_width / 5.0f - 10.0f, 10.0f)
-				, ImGuiSetCond_FirstUseEver
-				);
-			ImGui::Begin("Settings"
-				, NULL
-				, ImVec2(m_width / 5.0f, m_height / 3.0f)
-				, ImGuiWindowFlags_AlwaysAutoResize
+			showExampleDialog(this
+				, !m_mrtSupported
+				? "MRT or frame buffer texture format are not supported."
+				: NULL
 				);
 
-			ImGui::Separator();
+			if (m_mrtSupported)
+			{
+				if (m_oldWidth  != m_width
+				||  m_oldHeight != m_height
+				||  m_oldReset  != m_reset
+				||  !bgfx::isValid(m_fbh) )
+				{
+					// Recreate variable size render targets when resolution changes.
+					m_oldWidth  = m_width;
+					m_oldHeight = m_height;
+					m_oldReset  = m_reset;
 
-			ImGui::Text("Blend mode:");
+					if (bgfx::isValid(m_fbh) )
+					{
+						bgfx::destroy(m_fbh);
+					}
 
-			ImGui::RadioButton("None", &m_mode, 0);
-			ImGui::RadioButton("Separate", &m_mode, 1);
-			ImGui::RadioButton("MRT Independent", &m_mode, 2);
+					m_fbtextures[0] = bgfx::createTexture2D(uint16_t(m_width), uint16_t(m_height), false, 1, bgfx::TextureFormat::RGBA16F, BGFX_TEXTURE_RT);
+					m_fbtextures[1] = bgfx::createTexture2D(uint16_t(m_width), uint16_t(m_height), false, 1, bgfx::TextureFormat::R16F,    BGFX_TEXTURE_RT);
+					m_fbh = bgfx::createFrameBuffer(BX_COUNTOF(m_fbtextures), m_fbtextures, true);
+				}
 
-			ImGui::Separator();
+				ImGui::SetNextWindowPos(
+					ImVec2(m_width - m_width / 5.0f - 10.0f, 10.0f)
+					, ImGuiSetCond_FirstUseEver
+					);
+				ImGui::Begin("Settings"
+					, NULL
+					, ImVec2(m_width / 5.0f, m_height / 3.0f)
+					, ImGuiWindowFlags_AlwaysAutoResize
+					);
 
-			ImGui::Checkbox("Front to back", &m_frontToBack);
-			ImGui::Checkbox("Fade in/out", &m_fadeInOut);
+				ImGui::Separator();
 
-			ImGui::End();
-			imguiEndFrame();
+				ImGui::Text("Blend mode:");
 
-			// Set view 0 default viewport.
-			bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
-			bgfx::setViewRect(1, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+				ImGui::RadioButton("None", &m_mode, 0);
+				ImGui::RadioButton("Separate", &m_mode, 1);
+				ImGui::RadioButton("MRT Independent", &m_mode, 2);
 
-			int64_t now = bx::getHPCounter();
-			const double freq = double(bx::getHPFrequency() );
-			float time = (float)( (now-m_timeOffset)/freq);
+				ImGui::Separator();
 
-			// Reference:
-			// Weighted, Blended Order-Independent Transparency
-			// http://jcgt.org/published/0002/02/09/
-			// http://casual-effects.blogspot.com/2014/03/weighted-blended-order-independent.html
+				ImGui::Checkbox("Front to back", &m_frontToBack);
+				ImGui::Checkbox("Fade in/out", &m_fadeInOut);
 
-			float at[3] = { 0.0f, 0.0f, 0.0f };
-			float eye[3] = { 0.0f, 0.0f, -7.0f };
+				ImGui::End();
 
-			float view[16];
-			float proj[16];
+				// Set view 0 default viewport.
+				bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+				bgfx::setViewRect(1, 0, 0, uint16_t(m_width), uint16_t(m_height) );
 
-			// Set view and projection matrix for view 0.
-			bx::mtxLookAt(view, eye, at);
-			mtxProj(proj, 60.0f, float(m_width)/float(m_height), 0.1f, 100.0f);
+				int64_t now = bx::getHPCounter();
+				const double freq = double(bx::getHPFrequency() );
+				float time = (float)( (now-m_timeOffset)/freq);
 
-			bgfx::setViewTransform(0, view, proj);
+				// Reference:
+				// Weighted, Blended Order-Independent Transparency
+				// http://jcgt.org/published/0002/02/09/
+				// http://casual-effects.blogspot.com/2014/03/weighted-blended-order-independent.html
 
-			// Set palette color for index 0
-			bgfx::setPaletteColor(0, 0.0f, 0.0f, 0.0f, 0.0f);
+				float at[3] = { 0.0f, 0.0f, 0.0f };
+				float eye[3] = { 0.0f, 0.0f, -7.0f };
 
-			// Set palette color for index 1
-			bgfx::setPaletteColor(1, 1.0f, 1.0f, 1.0f, 1.0f);
+				float view[16];
+				float proj[16];
 
-			bgfx::setViewClear(0
-				, BGFX_CLEAR_COLOR|BGFX_CLEAR_DEPTH
-				, 1.0f // Depth
-				, 0    // Stencil
-				, 0    // FB texture 0, color palette 0
-				, 1 == m_mode ? 1 : 0 // FB texture 1, color palette 1
-				);
+				// Set view and projection matrix for view 0.
+				bx::mtxLookAt(view, eye, at);
+				mtxProj(proj, 60.0f, float(m_width)/float(m_height), 0.1f, 100.0f);
 
-			bgfx::setViewClear(1
-				, BGFX_CLEAR_COLOR|BGFX_CLEAR_DEPTH
-				, 1.0f // Depth
-				, 0    // Stencil
-				, 0    // Color palette 0
-				);
+				bgfx::setViewTransform(0, view, proj);
 
-			bgfx::FrameBufferHandle invalid = BGFX_INVALID_HANDLE;
-			bgfx::setViewFrameBuffer(0, 0 == m_mode ? invalid : m_fbh);
+				// Set palette color for index 0
+				bgfx::setPaletteColor(0, 0.0f, 0.0f, 0.0f, 0.0f);
 
-			// Set view and projection matrix for view 1.
-			bx::mtxIdentity(view);
+				// Set palette color for index 1
+				bgfx::setPaletteColor(1, 1.0f, 1.0f, 1.0f, 1.0f);
 
-			const bgfx::Caps* caps = bgfx::getCaps();
-			bx::mtxOrtho(proj, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 100.0f, 0.0f, caps->homogeneousDepth);
-			bgfx::setViewTransform(1, view, proj);
+				bgfx::setViewClear(0
+					, BGFX_CLEAR_COLOR|BGFX_CLEAR_DEPTH
+					, 1.0f // Depth
+					, 0    // Stencil
+					, 0    // FB texture 0, color palette 0
+					, 1 == m_mode ? 1 : 0 // FB texture 1, color palette 1
+					);
 
-			for (uint32_t depth = 0; depth < 3; ++depth)
-			{
-				uint32_t zz = m_frontToBack ? 2-depth : depth;
+				bgfx::setViewClear(1
+					, BGFX_CLEAR_COLOR|BGFX_CLEAR_DEPTH
+					, 1.0f // Depth
+					, 0    // Stencil
+					, 0    // Color palette 0
+					);
 
-				for (uint32_t yy = 0; yy < 3; ++yy)
-				{
-					for (uint32_t xx = 0; xx < 3; ++xx)
-					{
-						float color[4] = { xx*1.0f/3.0f, zz*1.0f/3.0f, yy*1.0f/3.0f, 0.5f };
+				bgfx::FrameBufferHandle invalid = BGFX_INVALID_HANDLE;
+				bgfx::setViewFrameBuffer(0, 0 == m_mode ? invalid : m_fbh);
 
-						if (m_fadeInOut
-						&&  zz == 1)
-						{
-							color[3] = bx::fsin(time*3.0f)*0.49f+0.5f;
-						}
+				// Set view and projection matrix for view 1.
+				bx::mtxIdentity(view);
+
+				const bgfx::Caps* caps = bgfx::getCaps();
+				bx::mtxOrtho(proj, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 100.0f, 0.0f, caps->homogeneousDepth);
+				bgfx::setViewTransform(1, view, proj);
+
+				for (uint32_t depth = 0; depth < 3; ++depth)
+				{
+					uint32_t zz = m_frontToBack ? 2-depth : depth;
 
-						bgfx::setUniform(u_color, color);
-
-						BX_UNUSED(time);
-						float mtx[16];
-						bx::mtxRotateXY(mtx, time*0.023f + xx*0.21f, time*0.03f + yy*0.37f);
-						//mtxIdentity(mtx);
-						mtx[12] = -2.5f + float(xx)*2.5f;
-						mtx[13] = -2.5f + float(yy)*2.5f;
-						mtx[14] = -2.5f + float(zz)*2.5f;
-
-						// Set transform for draw call.
-						bgfx::setTransform(mtx);
-
-						// Set vertex and index buffer.
-						bgfx::setVertexBuffer(0, m_vbh);
-						bgfx::setIndexBuffer(m_ibh);
-
-						const uint64_t state = 0
-							| BGFX_STATE_CULL_CW
-							| BGFX_STATE_RGB_WRITE
-							| BGFX_STATE_ALPHA_WRITE
-							| BGFX_STATE_DEPTH_TEST_LESS
-							| BGFX_STATE_MSAA
-							;
-
-						const uint64_t stateNoDepth = 0
-							| BGFX_STATE_CULL_CW
-							| BGFX_STATE_RGB_WRITE
-							| BGFX_STATE_ALPHA_WRITE
-							| BGFX_STATE_DEPTH_TEST_ALWAYS
-							| BGFX_STATE_MSAA
-							;
-
-						bgfx::ProgramHandle program = BGFX_INVALID_HANDLE;
-						switch (m_mode)
+					for (uint32_t yy = 0; yy < 3; ++yy)
+					{
+						for (uint32_t xx = 0; xx < 3; ++xx)
 						{
-						case 0:
-							// Set vertex and fragment shaders.
-							program = m_blend;
-
-							// Set render states.
-							bgfx::setState(state
-								| BGFX_STATE_BLEND_ALPHA
-								);
-							break;
-
-						case 1:
-							// Set vertex and fragment shaders.
-							program = m_wbSeparatePass;
-
-							// Set render states.
-							bgfx::setState(stateNoDepth
-								| BGFX_STATE_BLEND_FUNC_SEPARATE(BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ZERO, BGFX_STATE_BLEND_INV_SRC_ALPHA)
-								);
-							break;
-
-						default:
-							// Set vertex and fragment shaders.
-							program = m_wbPass;
-
-							// Set render states.
-							bgfx::setState(stateNoDepth
-								| BGFX_STATE_BLEND_FUNC(BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ONE)
-								| BGFX_STATE_BLEND_INDEPENDENT
-								, 0
-								| BGFX_STATE_BLEND_FUNC_RT_1(BGFX_STATE_BLEND_ZERO, BGFX_STATE_BLEND_SRC_COLOR)
-								);
-							break;
+							float color[4] = { xx*1.0f/3.0f, zz*1.0f/3.0f, yy*1.0f/3.0f, 0.5f };
+
+							if (m_fadeInOut
+							&&  zz == 1)
+							{
+								color[3] = bx::fsin(time*3.0f)*0.49f+0.5f;
+							}
+
+							bgfx::setUniform(u_color, color);
+
+							BX_UNUSED(time);
+							float mtx[16];
+							bx::mtxRotateXY(mtx, time*0.023f + xx*0.21f, time*0.03f + yy*0.37f);
+							//mtxIdentity(mtx);
+							mtx[12] = -2.5f + float(xx)*2.5f;
+							mtx[13] = -2.5f + float(yy)*2.5f;
+							mtx[14] = -2.5f + float(zz)*2.5f;
+
+							// Set transform for draw call.
+							bgfx::setTransform(mtx);
+
+							// Set vertex and index buffer.
+							bgfx::setVertexBuffer(0, m_vbh);
+							bgfx::setIndexBuffer(m_ibh);
+
+							const uint64_t state = 0
+								| BGFX_STATE_CULL_CW
+								| BGFX_STATE_RGB_WRITE
+								| BGFX_STATE_ALPHA_WRITE
+								| BGFX_STATE_DEPTH_TEST_LESS
+								| BGFX_STATE_MSAA
+								;
+
+							const uint64_t stateNoDepth = 0
+								| BGFX_STATE_CULL_CW
+								| BGFX_STATE_RGB_WRITE
+								| BGFX_STATE_ALPHA_WRITE
+								| BGFX_STATE_DEPTH_TEST_ALWAYS
+								| BGFX_STATE_MSAA
+								;
+
+							bgfx::ProgramHandle program = BGFX_INVALID_HANDLE;
+							switch (m_mode)
+							{
+							case 0:
+								// Set vertex and fragment shaders.
+								program = m_blend;
+
+								// Set render states.
+								bgfx::setState(state
+									| BGFX_STATE_BLEND_ALPHA
+									);
+								break;
+
+							case 1:
+								// Set vertex and fragment shaders.
+								program = m_wbSeparatePass;
+
+								// Set render states.
+								bgfx::setState(stateNoDepth
+									| BGFX_STATE_BLEND_FUNC_SEPARATE(BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ZERO, BGFX_STATE_BLEND_INV_SRC_ALPHA)
+									);
+								break;
+
+							default:
+								// Set vertex and fragment shaders.
+								program = m_wbPass;
+
+								// Set render states.
+								bgfx::setState(stateNoDepth
+									| BGFX_STATE_BLEND_FUNC(BGFX_STATE_BLEND_ONE, BGFX_STATE_BLEND_ONE)
+									| BGFX_STATE_BLEND_INDEPENDENT
+									, 0
+									| BGFX_STATE_BLEND_FUNC_RT_1(BGFX_STATE_BLEND_ZERO, BGFX_STATE_BLEND_SRC_COLOR)
+									);
+								break;
+							}
+
+							// Submit primitive for rendering to view 0.
+							bgfx::submit(0, program);
 						}
-
-						// Submit primitive for rendering to view 0.
-						bgfx::submit(0, program);
 					}
 				}
-			}
 
-			if (0 != m_mode)
-			{
-				bgfx::setTexture(0, s_texColor0, m_fbtextures[0]);
-				bgfx::setTexture(1, s_texColor1, m_fbtextures[1]);
-				bgfx::setState(0
-					| BGFX_STATE_RGB_WRITE
-					| BGFX_STATE_BLEND_FUNC(BGFX_STATE_BLEND_INV_SRC_ALPHA, BGFX_STATE_BLEND_SRC_ALPHA)
-					);
-				screenSpaceQuad( (float)m_width, (float)m_height, s_flipV);
-				bgfx::submit(1
-					, 1 == m_mode ? m_wbSeparateBlit : m_wbBlit
-					);
+				if (0 != m_mode)
+				{
+					bgfx::setTexture(0, s_texColor0, m_fbtextures[0]);
+					bgfx::setTexture(1, s_texColor1, m_fbtextures[1]);
+					bgfx::setState(0
+						| BGFX_STATE_RGB_WRITE
+						| BGFX_STATE_BLEND_FUNC(BGFX_STATE_BLEND_INV_SRC_ALPHA, BGFX_STATE_BLEND_SRC_ALPHA)
+						);
+					screenSpaceQuad( (float)m_width, (float)m_height, s_flipV);
+					bgfx::submit(1
+						, 1 == m_mode ? m_wbSeparateBlit : m_wbBlit
+						);
+				}
 			}
 
+			imguiEndFrame();
+
 			// Advance to next frame. Rendering thread will be kicked to
 			// process submitted rendering primitives.
 			bgfx::frame();
@@ -495,6 +513,7 @@ public:
 	int32_t m_mode;
 	bool m_frontToBack;
 	bool m_fadeInOut;
+	bool m_mrtSupported;
 
 	uint32_t m_oldWidth;
 	uint32_t m_oldHeight;

examples/24-nbody/nbody.cpp

@@ -142,12 +142,12 @@ public:
 			);
 
 		const bgfx::Caps* caps = bgfx::getCaps();
-		const bool computeSupported  = !!(caps->supported & BGFX_CAPS_COMPUTE);
-		const bool indirectSupported = !!(caps->supported & BGFX_CAPS_DRAW_INDIRECT);
+		m_computeSupported  = !!(caps->supported & BGFX_CAPS_COMPUTE);
+		m_indirectSupported = !!(caps->supported & BGFX_CAPS_DRAW_INDIRECT);
 
 		imguiCreate();
 
-		if (computeSupported)
+		if (m_computeSupported)
 		{
 			bgfx::VertexDecl quadVertexDecl;
 			quadVertexDecl.begin()
@@ -189,7 +189,7 @@ public:
 			m_indirectProgram = BGFX_INVALID_HANDLE;
 			m_indirectBuffer  = BGFX_INVALID_HANDLE;
 
-			if (indirectSupported)
+			if (m_indirectSupported)
 			{
 				m_indirectProgram = bgfx::createProgram(loadShader("cs_indirect"), true);
 				m_indirectBuffer  = bgfx::createIndirectBuffer(2);
@@ -219,22 +219,25 @@ public:
 		cameraDestroy();
 		imguiDestroy();
 
-		if (bgfx::isValid(m_indirectProgram) )
+		if (m_computeSupported)
 		{
-			bgfx::destroy(m_indirectProgram);
-			bgfx::destroy(m_indirectBuffer);
-		}
+			if (m_indirectSupported)
+			{
+				bgfx::destroy(m_indirectProgram);
+				bgfx::destroy(m_indirectBuffer);
+			}
 
-		bgfx::destroy(u_params);
-		bgfx::destroy(m_currPositionBuffer0);
-		bgfx::destroy(m_currPositionBuffer1);
-		bgfx::destroy(m_prevPositionBuffer0);
-		bgfx::destroy(m_prevPositionBuffer1);
-		bgfx::destroy(m_updateInstancesProgram);
-		bgfx::destroy(m_initInstancesProgram);
-		bgfx::destroy(m_ibh);
-		bgfx::destroy(m_vbh);
-		bgfx::destroy(m_particleProgram);
+			bgfx::destroy(u_params);
+			bgfx::destroy(m_currPositionBuffer0);
+			bgfx::destroy(m_currPositionBuffer1);
+			bgfx::destroy(m_prevPositionBuffer0);
+			bgfx::destroy(m_prevPositionBuffer1);
+			bgfx::destroy(m_updateInstancesProgram);
+			bgfx::destroy(m_initInstancesProgram);
+			bgfx::destroy(m_ibh);
+			bgfx::destroy(m_vbh);
+			bgfx::destroy(m_particleProgram);
+		}
 
 		// Shutdown bgfx.
 		bgfx::shutdown();
@@ -257,14 +260,13 @@ public:
 				, uint16_t(m_height)
 				);
 
-			showExampleDialog(this);
-
-			const bgfx::Caps* caps = bgfx::getCaps();
-			const bool computeSupported  = !!(caps->supported & BGFX_CAPS_COMPUTE);
-			const bool indirectSupported = !!(caps->supported & BGFX_CAPS_DRAW_INDIRECT);
+			showExampleDialog(this
+				, !m_computeSupported
+				? "Compute is not supported."
+				: NULL
+				);
 
 			int64_t now = bx::getHPCounter();
-			float time = (float)( (now - m_timeOffset)/double(bx::getHPFrequency() ) );
 			static int64_t last = now;
 			const int64_t frameTime = now - last;
 			last = now;
@@ -274,7 +276,7 @@ public:
 			// Set view 0 default viewport.
 			bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
 
-			if (computeSupported)
+			if (m_computeSupported)
 			{
 				ImGui::SetNextWindowPos(
 					  ImVec2(m_width - m_width / 5.0f - 10.0f, 10.0f)
@@ -318,7 +320,7 @@ public:
 
 				ImGui::Separator();
 
-				if (indirectSupported)
+				if (m_indirectSupported)
 				{
 					ImGui::Checkbox("Use draw/dispatch indirect", &m_useIndirect);
 				}
@@ -430,15 +432,6 @@ public:
 					bgfx::submit(0, m_particleProgram);
 				}
 			}
-			else
-			{
-				bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
-
-				bool blink = uint32_t(time*3.0f)&1;
-				bgfx::dbgTextPrintf(0, 0, blink ? 0x1f : 0x01, " Compute is not supported by GPU. ");
-
-				bgfx::touch(0);
-			}
 
 			imguiEndFrame();
 
@@ -459,6 +452,8 @@ public:
 	uint32_t m_debug;
 	uint32_t m_reset;
 	bool m_useIndirect;
+	bool m_computeSupported;
+	bool m_indirectSupported;
 
 	ParamsData m_paramsData;
 

examples/26-occlusion/occlusion.cpp

@@ -119,9 +119,15 @@ public:
 		// Create program from shaders.
 		m_program = loadProgram("vs_cubes", "fs_cubes");
 
-		for (uint32_t ii = 0; ii < BX_COUNTOF(m_occlusionQueries); ++ii)
+		const bgfx::Caps* caps = bgfx::getCaps();
+		m_occlusionQuerySupported = !!(caps->supported & BGFX_CAPS_OCCLUSION_QUERY);
+
+		if (m_occlusionQuerySupported)
 		{
-			m_occlusionQueries[ii] = bgfx::createOcclusionQuery();
+			for (uint32_t ii = 0; ii < BX_COUNTOF(m_occlusionQueries); ++ii)
+			{
+				m_occlusionQueries[ii] = bgfx::createOcclusionQuery();
+			}
 		}
 
 		cameraCreate();
@@ -142,9 +148,12 @@ public:
 		// Cleanup.
 		cameraDestroy();
 
-		for (uint32_t ii = 0; ii < BX_COUNTOF(m_occlusionQueries); ++ii)
+		if (m_occlusionQuerySupported)
 		{
-			bgfx::destroy(m_occlusionQueries[ii]);
+			for (uint32_t ii = 0; ii < BX_COUNTOF(m_occlusionQueries); ++ii)
+			{
+				bgfx::destroy(m_occlusionQueries[ii]);
+			}
 		}
 
 		bgfx::destroy(m_ibh);
@@ -171,112 +180,119 @@ public:
 				, uint16_t(m_height)
 				);
 
-			showExampleDialog(this);
+			showExampleDialog(this
+				, !m_occlusionQuerySupported
+				? "Occlusion query is not supported."
+				: NULL
+				);
 
 			imguiEndFrame();
 
-			int64_t now = bx::getHPCounter();
-			static int64_t last = now;
-			const int64_t frameTime = now - last;
-			last = now;
-			const double freq = double(bx::getHPFrequency() );
-			const float time = (float)( (now-m_timeOffset)/double(bx::getHPFrequency() ) );
-			const float deltaTime = float(frameTime/freq);
-
-			// Update camera.
-			float view[16];
-			cameraUpdate(deltaTime, m_state.m_mouse);
-			cameraGetViewMtx(view);
-
-			// Set view and projection matrix for view 0.
-			const bgfx::HMD* hmd = bgfx::getHMD();
-			if (NULL != hmd && 0 != (hmd->flags & BGFX_HMD_RENDERING) )
+			if (m_occlusionQuerySupported)
 			{
-				float viewHead[16];
-				float eye[3] = {};
-				bx::mtxQuatTranslationHMD(viewHead, hmd->eye[0].rotation, eye);
+				int64_t now = bx::getHPCounter();
+				static int64_t last = now;
+				const int64_t frameTime = now - last;
+				last = now;
+				const double freq = double(bx::getHPFrequency() );
+				const float time = (float)( (now-m_timeOffset)/double(bx::getHPFrequency() ) );
+				const float deltaTime = float(frameTime/freq);
+
+				// Update camera.
+				float view[16];
+				cameraUpdate(deltaTime, m_state.m_mouse);
+				cameraGetViewMtx(view);
+
+				// Set view and projection matrix for view 0.
+				const bgfx::HMD* hmd = bgfx::getHMD();
+				if (NULL != hmd && 0 != (hmd->flags & BGFX_HMD_RENDERING) )
+				{
+					float viewHead[16];
+					float eye[3] = {};
+					bx::mtxQuatTranslationHMD(viewHead, hmd->eye[0].rotation, eye);
 
-				float tmp[16];
-				bx::mtxMul(tmp, view, viewHead);
+					float tmp[16];
+					bx::mtxMul(tmp, view, viewHead);
 
-				bgfx::setViewTransform(0, tmp, hmd->eye[0].projection);
-				bgfx::setViewRect(0, 0, 0, hmd->width, hmd->height);
+					bgfx::setViewTransform(0, tmp, hmd->eye[0].projection);
+					bgfx::setViewRect(0, 0, 0, hmd->width, hmd->height);
 
-				bgfx::setViewTransform(1, tmp, hmd->eye[1].projection);
-				bgfx::setViewRect(1, 0, 0, hmd->width, hmd->height);
-			}
-			else
-			{
-				float proj[16];
-				bx::mtxProj(proj, 90.0f, float(m_width)/float(m_height), 0.1f, 10000.0f, bgfx::getCaps()->homogeneousDepth);
+					bgfx::setViewTransform(1, tmp, hmd->eye[1].projection);
+					bgfx::setViewRect(1, 0, 0, hmd->width, hmd->height);
+				}
+				else
+				{
+					float proj[16];
+					bx::mtxProj(proj, 90.0f, float(m_width)/float(m_height), 0.1f, 10000.0f, bgfx::getCaps()->homogeneousDepth);
 
-				bgfx::setViewTransform(0, view, proj);
-				bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+					bgfx::setViewTransform(0, view, proj);
+					bgfx::setViewRect(0, 0, 0, uint16_t(m_width), uint16_t(m_height) );
 
-				bgfx::setViewTransform(1, view, proj);
-				bgfx::setViewRect(1, 0, 0, uint16_t(m_width), uint16_t(m_height) );
+					bgfx::setViewTransform(1, view, proj);
+					bgfx::setViewRect(1, 0, 0, uint16_t(m_width), uint16_t(m_height) );
 
-				float at[3]  = {  0.0f,  0.0f,   0.0f };
-				float eye[3] = { 17.5f, 10.0f, -17.5f };
-				bx::mtxLookAt(view, eye, at);
+					float at[3]  = {  0.0f,  0.0f,   0.0f };
+					float eye[3] = { 17.5f, 10.0f, -17.5f };
+					bx::mtxLookAt(view, eye, at);
 
-				bgfx::setViewTransform(2, view, proj);
-				bgfx::setViewRect(2, 10, uint16_t(m_height - m_height/4 - 10), uint16_t(m_width/4), uint16_t(m_height/4) );
-			}
+					bgfx::setViewTransform(2, view, proj);
+					bgfx::setViewRect(2, 10, uint16_t(m_height - m_height/4 - 10), uint16_t(m_width/4), uint16_t(m_height/4) );
+				}
 
-			bgfx::touch(0);
-			bgfx::touch(2);
+				bgfx::touch(0);
+				bgfx::touch(2);
 
-			uint8_t img[CUBES_DIM*CUBES_DIM*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)
+				for (uint32_t yy = 0; yy < CUBES_DIM; ++yy)
 				{
-					float mtx[16];
-					bx::mtxRotateXY(mtx, time + xx*0.21f, time + yy*0.37f);
-					mtx[12] = -(CUBES_DIM-1) * 3.0f / 2.0f + float(xx)*3.0f;
-					mtx[13] = 0.0f;
-					mtx[14] = -(CUBES_DIM-1) * 3.0f / 2.0f + float(yy)*3.0f;
-
-					bgfx::OcclusionQueryHandle occlusionQuery = m_occlusionQueries[yy*CUBES_DIM+xx];
-
-					bgfx::setTransform(mtx);
-					bgfx::setVertexBuffer(0, m_vbh);
-					bgfx::setIndexBuffer(m_ibh);
-					bgfx::setCondition(occlusionQuery, true);
-					bgfx::setState(BGFX_STATE_DEFAULT);
-					bgfx::submit(0, m_program);
-
-					bgfx::setTransform(mtx);
-					bgfx::setVertexBuffer(0, m_vbh);
-					bgfx::setIndexBuffer(m_ibh);
-					bgfx::setState(0
-						| BGFX_STATE_DEPTH_TEST_LEQUAL
-						| BGFX_STATE_CULL_CW
-						);
-					bgfx::submit(1, m_program, occlusionQuery);
-
-					bgfx::setTransform(mtx);
-					bgfx::setVertexBuffer(0, m_vbh);
-					bgfx::setIndexBuffer(m_ibh);
-					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;
+					for (uint32_t xx = 0; xx < CUBES_DIM; ++xx)
+					{
+						float mtx[16];
+						bx::mtxRotateXY(mtx, time + xx*0.21f, time + yy*0.37f);
+						mtx[12] = -(CUBES_DIM-1) * 3.0f / 2.0f + float(xx)*3.0f;
+						mtx[13] = 0.0f;
+						mtx[14] = -(CUBES_DIM-1) * 3.0f / 2.0f + float(yy)*3.0f;
+
+						bgfx::OcclusionQueryHandle occlusionQuery = m_occlusionQueries[yy*CUBES_DIM+xx];
+
+						bgfx::setTransform(mtx);
+						bgfx::setVertexBuffer(0, m_vbh);
+						bgfx::setIndexBuffer(m_ibh);
+						bgfx::setCondition(occlusionQuery, true);
+						bgfx::setState(BGFX_STATE_DEFAULT);
+						bgfx::submit(0, m_program);
+
+						bgfx::setTransform(mtx);
+						bgfx::setVertexBuffer(0, m_vbh);
+						bgfx::setIndexBuffer(m_ibh);
+						bgfx::setState(0
+							| BGFX_STATE_DEPTH_TEST_LEQUAL
+							| BGFX_STATE_CULL_CW
+							);
+						bgfx::submit(1, m_program, occlusionQuery);
+
+						bgfx::setTransform(mtx);
+						bgfx::setVertexBuffer(0, m_vbh);
+						bgfx::setIndexBuffer(m_ibh);
+						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;
+					}
 				}
-			}
 
-			for (uint16_t xx = 0; xx < CUBES_DIM; ++xx)
-			{
-				bgfx::dbgTextImage(5 + xx*2, 5, 1, CUBES_DIM, img + xx*2, CUBES_DIM*2);
-			}
+				for (uint16_t xx = 0; xx < CUBES_DIM; ++xx)
+				{
+					bgfx::dbgTextImage(5 + xx*2, 5, 1, CUBES_DIM, img + xx*2, CUBES_DIM*2);
+				}
 
-			int32_t numPixels = 0;
-			bgfx::getResult(m_occlusionQueries[0], &numPixels);
-			bgfx::dbgTextPrintf(5, 5 + CUBES_DIM + 1, 0xf, "%d", numPixels);
+				int32_t numPixels = 0;
+				bgfx::getResult(m_occlusionQueries[0], &numPixels);
+				bgfx::dbgTextPrintf(5, 5 + CUBES_DIM + 1, 0xf, "%d", numPixels);
+			}
 
 			// Advance to next frame. Rendering thread will be kicked to
 			// process submitted rendering primitives.
@@ -299,6 +315,7 @@ public:
 	bgfx::IndexBufferHandle m_ibh;
 	bgfx::ProgramHandle m_program;
 	int64_t m_timeOffset;
+	bool m_occlusionQuerySupported;
 
 	bgfx::OcclusionQueryHandle m_occlusionQueries[CUBES_DIM*CUBES_DIM];