如何使用 Metal 在 Mac 应用程序中实现抗锯齿？

Question

我正在为 MacOs 制作一个应用程序，但我在 Metal 中的抗锯齿实现方面遇到了问题。 编译时出现以下错误： validateAttachmentOnDevice:540: failed assertion MTLRenderPassDescriptor 渲染目标的样本计数不一致。 这是我用来实现纹理的代码：

- (void)makeTextures {

if ([depthTexture width] != drawableSize.width || [depthTexture height] != drawableSize.height)
{

    MTLTextureDescriptor *colorDescriptor = [MTLTextureDescriptor new];
    colorDescriptor.textureType = MTLTextureType2DMultisample;
    colorDescriptor.sampleCount = 4;
    colorDescriptor.pixelFormat = vista.colorPixelFormat;
    colorDescriptor.width = drawableSize.width;
    colorDescriptor.height = drawableSize.height;
    colorDescriptor.usage = MTLTextureUsageRenderTarget;
    colorDescriptor.storageMode = MTLStorageModePrivate;

    msaaColorTexture = [view.device newTextureWithDescriptor:colorDescriptor];

    MTLTextureDescriptor *resolveDescriptor = [MTLTextureDescriptor new];
    resolveDescriptor.textureType = MTLTextureType2D;
    resolveDescriptor.pixelFormat = vista.colorPixelFormat;
    resolveDescriptor.width = drawableSize.width;
    resolveDescriptor.height = drawableSize.height;
    resolveDescriptor.storageMode = MTLStorageModePrivate;

    msaaResolveColorTexture = [view.device newTextureWithDescriptor:resolveDescriptor];

    MTLTextureDescriptor *desc = [MTLTextureDescriptor new];
    desc.textureType = MTLTextureType2DMultisample;
    desc.sampleCount = 4;
    desc.pixelFormat = MTLPixelFormatDepth32Float;
    desc.width = drawableSize.width;
    desc.height = drawableSize.height;
    desc.usage = MTLTextureUsageRenderTarget;
    desc.storageMode = MTLStorageModePrivate;

    depthTexture = [view.device newTextureWithDescriptor:desc];
}

}

如果在创建 MTLRenderPipelineDescriptor 时我 add.samplecount = 4;，则错误消失，但视图中没有绘制任何内容。 这是 de PipelineDescriptor 创建：

MTLRenderPipelineDescriptor *pipelineStateDescriptor = [MTLRenderPipelineDescriptor new];
pipelineStateDescriptor.label = @"Simple Pipeline";
pipelineStateDescriptor.vertexFunction = vertexFunction;
pipelineStateDescriptor.fragmentFunction = fragmentFunction;
pipelineStateDescriptor.colorAttachments[0].pixelFormat = vista.colorPixelFormat;
pipelineStateDescriptor.depthAttachmentPixelFormat = MTLPixelFormatDepth32Float;

// No error but black view.
//pipelineStateDescriptor.sampleCount = 4;

NSError *error;

pipelineState = [view.device newRenderPipelineStateWithDescriptor:pipelineStateDescriptor error:&error];

// Depth stencil.

MTLDepthStencilDescriptor *depthStencilDescriptor = [MTLDepthStencilDescriptor new];
depthStencilDescriptor.depthCompareFunction = MTLCompareFunctionLess;
depthStencilDescriptor.depthWriteEnabled = YES;
depthStencilState = [view.device newDepthStencilStateWithDescriptor:depthStencilDescriptor];

并通过描述符：

if (passDescriptor != nil) {

    passDescriptor.colorAttachments[0].texture = msaaColorTexture;
    passDescriptor.colorAttachments[0].resolveTexture = msaaResolveColorTexture;
    passDescriptor.colorAttachments[0].clearColor = MTLClearColorMake(1.0f, 1.0f, 1.0f, 1.0f);
    passDescriptor.colorAttachments[0].storeAction = MTLStoreActionMultisampleResolve;
    passDescriptor.colorAttachments[0].loadAction = MTLLoadActionClear;

    passDescriptor.depthAttachment.texture = depthTexture;
    passDescriptor.depthAttachment.clearDepth = 1.0;
    passDescriptor.depthAttachment.loadAction = MTLLoadActionClear;
    passDescriptor.depthAttachment.storeAction = MTLStoreActionStore;
.
.
.

任何建议...在此先感谢。