public void BindAttributes(VertexStreamRL vertexStream, IProgram program, VertexFormat vertexFormat)
        {
            foreach (var mapping in mappings)
            {
                var programAttribute = program.Attribute(mapping.Name);
                if (programAttribute == null)
                {
                    continue;
                }
                var vertexFormatAttribute = vertexFormat.FindAttribute(mapping.SrcUsage, mapping.SrcIndex);
                if (vertexFormatAttribute == null)
                {
                    continue;
                }

                vertexStream.Add(
                    mapping,
                    vertexFormatAttribute,
                    vertexFormat.Stride,
                    programAttribute.Slot
                    );
            }
        }