Metal中矛盾的textureUsage持续错误？

Question

这发生在我尝试使用 CAMetalLayer 渲染金属时，以及我下载的许多 'Metal By Example' 示例代码中。问题出在 'texture' 我猜，这里有一些代码，我不能提供全部，但我会尽量提供最相关的部分。它不接受纹理描述符，将其打印到控制台中。

断言失败 `MTLTextureDescriptor: Depth、Stencil、DepthStencil 和 Multisample 纹理必须使用 MTLStorageModePrivate 或 MTLStorageModeMemoryless 存储模式分配。'

- (void)buildDepthTexture
{
    CGSize drawableSize = self.layer.drawableSize;
    MTLTextureDescriptor *descriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatDepth32Float
                                                                                          width:drawableSize.width
                                                                                         height:drawableSize.height
                                                                                      mipmapped:NO];
    self.depthTexture = [self.device newTextureWithDescriptor:descriptor]; // Thread 1: signal SIGABRT
    [self.depthTexture setLabel:@"Depth Texture"];
}

同样，这是示例代码，可能有效，但不再有效。所以我很喜欢，让我们用私有存储模式或一些垃圾来分配它。 descriptor.storageMode = MTLStorageModePrivate;

但是当我这样做时，无法在draw 中创建渲染通道描述符。

断言失败`Texture at depthAttachment has usage (0x01) which doesn't specify MTLTextureUsageRenderTarget (0x04)'

MTLRenderPassDescriptor *renderPass = [self newRenderPassWithColorAttachmentTexture:[drawable texture]];

id<MTLCommandBuffer> commandBuffer = [self.commandQueue commandBuffer];

id<MTLRenderCommandEncoder> commandEncoder = [commandBuffer renderCommandEncoderWithDescriptor:renderPass]; //Thread 1: signal SIGABRT

这是newRenderPassWithColorAttachmentTexture 的代码。

- (MTLRenderPassDescriptor *)newRenderPassWithColorAttachmentTexture:(id<MTLTexture>)texture
{
    MTLRenderPassDescriptor *renderPass = [MTLRenderPassDescriptor new];

    renderPass.colorAttachments[0].texture = texture;
    renderPass.colorAttachments[0].loadAction = MTLLoadActionClear;
    renderPass.colorAttachments[0].storeAction = MTLStoreActionStore;
    renderPass.colorAttachments[0].clearColor = MBEClearColor;

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

    return renderPass;
}

所以基本上，似乎两个不同的渲染阶段需要两个不同的互斥条件。如果一个工作，另一个不工作，反之亦然。看起来不可能，说真的，我该怎么办？什么给了？

Answer 1

您应该提供纹理使用说明：

    - (void)buildDepthTexture
    {
        CGSize drawableSize = self.layer.drawableSize;
        MTLTextureDescriptor *descriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatDepth32Float
                                                                                              width:drawableSize.width
                                                                                             height:drawableSize.height
                                                                                          mipmapped:NO];
    
        descriptor.storageMode = MTLStorageModePrivate;
        descriptor.usage = MTLTextureUsageRenderTarget | MTLTextureUsageShaderRead | MTLTextureUsageShaderWrite;

        self.depthTexture = [self.device newTextureWithDescriptor:descriptor]; // Thread 1: signal SIGABRT
        [self.depthTexture setLabel:@"Depth Texture"];
    }