Fixed issue #308.

examples/05-instancing/instancing.cpp

@@ -132,7 +132,7 @@ int _main_(int /*_argc*/, char** /*_argv*/)
 		{
 			float at[3]  = { 0.0f, 0.0f,   0.0f };
 			float eye[3] = { 0.0f, 0.0f, -35.0f };
-			
+
 			// Set view and projection matrix for view 0.
 			const bgfx::HMD* hmd = bgfx::getHMD();
 			if (NULL != hmd)
@@ -171,9 +171,9 @@ int _main_(int /*_argc*/, char** /*_argv*/)
 				uint8_t* data = idb->data;
 
 				// Write instance data for 11x11 cubes.
-				for (uint32_t yy = 0; yy < 11; ++yy)
+				for (uint32_t yy = 0, numInstances = 0; yy < 11 && numInstances < idb->num; ++yy)
 				{
-					for (uint32_t xx = 0; xx < 11; ++xx)
+					for (uint32_t xx = 0; xx < 11 && numInstances < idb->num; ++xx, ++numInstances)
 					{
 						float* mtx = (float*)data;
 						bx::mtxRotateXY(mtx, time + xx*0.21f, time + yy*0.37f);
@@ -209,7 +209,7 @@ int _main_(int /*_argc*/, char** /*_argv*/)
 			}
 		}
 
-		// Advance to next frame. Rendering thread will be kicked to 
+		// Advance to next frame. Rendering thread will be kicked to
 		// process submitted rendering primitives.
 		bgfx::frame();
 	}

src/bgfx_p.h

@@ -1478,8 +1478,8 @@ namespace bgfx
 
 		uint32_t allocTransientIndexBuffer(uint32_t& _num)
 		{
-			uint32_t offset = m_iboffset;
-			m_iboffset = offset + (_num+1)*sizeof(uint16_t);
+			uint32_t offset = bx::strideAlign(m_iboffset, sizeof(uint16_t) );
+			m_iboffset = offset + _num*sizeof(uint16_t);
 			m_iboffset = bx::uint32_min(m_iboffset, BGFX_CONFIG_TRANSIENT_INDEX_BUFFER_SIZE);
 			_num = (m_iboffset-offset)/sizeof(uint16_t);
 			return offset;
@@ -1497,7 +1497,7 @@ namespace bgfx
 		uint32_t allocTransientVertexBuffer(uint32_t& _num, uint16_t _stride)
 		{
 			uint32_t offset = bx::strideAlign(m_vboffset, _stride);
-			m_vboffset = offset + (_num+1) * _stride;
+			m_vboffset = offset + _num * _stride;
 			m_vboffset = bx::uint32_min(m_vboffset, BGFX_CONFIG_TRANSIENT_VERTEX_BUFFER_SIZE);
 			_num = (m_vboffset-offset)/_stride;
 			return offset;
@@ -2087,7 +2087,7 @@ namespace bgfx
 		{
 			DynamicIndexBufferHandle handle = BGFX_INVALID_HANDLE;
 			const uint32_t indexSize = 0 == (_flags & BGFX_BUFFER_INDEX32) ? 2 : 4;
-			uint32_t size = BX_ALIGN_16( (_num+1)*indexSize);
+			uint32_t size = BX_ALIGN_16(_num*indexSize);
 
 			uint64_t ptr = 0;
 			if (0 != (_flags & BGFX_BUFFER_COMPUTE_WRITE) )
@@ -2236,7 +2236,7 @@ namespace bgfx
 		BGFX_API_FUNC(DynamicVertexBufferHandle createDynamicVertexBuffer(uint32_t _num, const VertexDecl& _decl, uint8_t _flags) )
 		{
 			DynamicVertexBufferHandle handle = BGFX_INVALID_HANDLE;
-			uint32_t size = bx::strideAlign16( (_num+1)*_decl.m_stride, _decl.m_stride);
+			uint32_t size = bx::strideAlign16(_num*_decl.m_stride, _decl.m_stride);
 
 			uint64_t ptr = 0;
 			if (0 != (_flags & BGFX_BUFFER_COMPUTE_WRITE) )