在金属中使用stride类似于openGL

Question

我有一个缓冲区，顶点有一个步幅。如何在金属中指定这一点？我似乎找不到任何例子。谢谢!

Answer 1

请查看MTLRenderPipelineDescriptor的一部分MTLVertexBufferLayoutDescriptor。它有stride成员。

下面是以交错方式设置存储在一个顶点缓冲区中的三个顶点属性的示例。在end：vertexDescriptor.layouts[0].stride = 32;旁边设置stride

MTLRenderPipelineDescriptor *pipelineDescriptor = [[MTLRenderPipelineDescriptor alloc] init];

MTLVertexDescriptor *vertexDescriptor = [MTLVertexDescriptor vertexDescriptor];
vertexDescriptor.attributes[0].offset = 0;
vertexDescriptor.attributes[0].format = MTLVertexFormatFloat3; // position
vertexDescriptor.attributes[0].bufferIndex = 0;
vertexDescriptor.attributes[1].offset = 12;
vertexDescriptor.attributes[1].format = MTLVertexFormatFloat3; // normal
vertexDescriptor.attributes[1].bufferIndex = 0;
vertexDescriptor.attributes[2].offset = 24;
vertexDescriptor.attributes[2].format = MTLVertexFormatFloat2; // texCoords
vertexDescriptor.attributes[2].bufferIndex = 0;

vertexDescriptor.layouts[0].stepRate = 1;
vertexDescriptor.layouts[0].stepFunction = MTLVertexStepFunctionPerVertex;
vertexDescriptor.layouts[0].stride = 32;

pipelineDescriptor.vertexDescriptor = vertexDescriptor;