Fixed dynamic index buffer offset.

src/bgfx_p.h

@@ -2990,7 +2990,11 @@ namespace bgfx
 
 		BGFX_API_FUNC(void setIndexBuffer(DynamicIndexBufferHandle _handle, uint32_t _firstIndex, uint32_t _numIndices) )
 		{
-			m_submit->setIndexBuffer(m_dynamicIndexBuffers[_handle.idx].m_handle, _firstIndex, _numIndices);
+			const DynamicIndexBuffer& dib = m_dynamicIndexBuffers[_handle.idx];
+			m_submit->setIndexBuffer(dib.m_handle
+					, dib.m_offset / 2 + _firstIndex * 2
+					, _numIndices
+					);
 		}
 
 		BGFX_API_FUNC(void setIndexBuffer(const TransientIndexBuffer* _tib, uint32_t _firstIndex, uint32_t _numIndices) )