为什么我不能成功启动MPSMatrix？

Question

我想知道为什么我不能成功初始化MPSMatrix？对象方法initWith只返回一个nil（这意味着init不成功）。我的代码如下所示，我想创建一个名为matrixA的MPSMatrix，但只是回来了。

id<MTLDevice> device = MTLCreateSystemDefaultDevice();
id<MTLCommandQueue> commandQueue = [device newCommandQueue];
id<MTLCommandBuffer> mpsBuffer = commandQueue.commandBuffer;
float arrayA[5*6] =
    {1,1,1,1,1,1,
     2,2,2,2,2,2,
     3,3,3,3,3,3,
     4,4,4,4,4,4,
     5,5,5,5,5,5};
float arrayB[6*5] =
    {1,1,1,1,1,
     2,2,2,2,2,
     3,3,3,3,3,
     4,4,4,4,4,
     5,5,5,5,5,
     6,6,6,6,6};
float arrayC[5*5] = {0};
id<MTLBuffer> bufferA = [device newBufferWithBytes:arrayA length:5*6*4 options:MTLResourceCPUCacheModeDefaultCache];
id<MTLBuffer> bufferB = [device newBufferWithBytes:arrayB length:6*5*4 options:MTLResourceCPUCacheModeDefaultCache];
id<MTLBuffer> bufferC = [device newBufferWithBytes:arrayC length:5*5*4 options:MTLResourceCPUCacheModeDefaultCache];

MPSMatrixDescriptor * descA = [MPSMatrixDescriptor matrixDescriptorWithDimensions:5 columns:6 rowBytes:6*4 dataType:MPSDataTypeFloat32];
MPSMatrixDescriptor * descB = [MPSMatrixDescriptor matrixDescriptorWithDimensions:6 columns:5 rowBytes:5*4 dataType:MPSDataTypeFloat32];
MPSMatrixDescriptor * descC = [MPSMatrixDescriptor matrixDescriptorWithDimensions:5 columns:5 rowBytes:5*4 dataType:MPSDataTypeFloat32];

MPSMatrix * matrixA = [[MPSMatrix alloc] initWithBuffer:bufferA descriptor:descA];
MPSMatrix * matrixB = [[MPSMatrix alloc] initWithBuffer:bufferB descriptor:descB];
MPSMatrix * matrixC = [[MPSMatrix alloc] initWithBuffer:bufferC descriptor:descC];

Answer 1

我发现那是因为我以前调试的设备是5s，它只是部分地支持金属性能着色器基础。它可以获得MPSMatrixDescriptor但是它无法获得MPSMatrix。 叹息。

Answer 2

是。使用MPSSupportsMTLDevice确定MetalPerformanceShaders.framework是否支持MTLDevice。事实上，我的iPad mini2也不支持MPS。如下：