Objective C to swift conversion for unions

Hi I am trying to convert below objective c code into swift but struggling to convert unions which are supported into C but not directly in swift.

I am not sure how I can convert below union type and pass it to MTLTexture getbytes?

  union {      float f[2];      unsigned char bytes[8];  } u;  

Also last part where I want to print these float values with log statement.

It would be great if I get working swift conversion for below code snippet.

  id<MTLDevice> device = MTLCreateSystemDefaultDevice();  id<MTLCommandQueue> queue = [device newCommandQueue];  id<MTLCommandBuffer> commandBuffer = [queue commandBuffer];    MTKTextureLoader *textureLoader = [[MTKTextureLoader alloc] initWithDevice:device];  id<MTLTexture> sourceTexture = [textureLoader newTextureWithCGImage:image.CGImage options:nil error:nil];      CGColorSpaceRef srcColorSpace = CGColorSpaceCreateDeviceRGB();  CGColorSpaceRef dstColorSpace = CGColorSpaceCreateDeviceGray();  CGColorConversionInfoRef conversionInfo = CGColorConversionInfoCreate(srcColorSpace, dstColorSpace);  MPSImageConversion *conversion = [[MPSImageConversion alloc] initWithDevice:device                                                                     srcAlpha:MPSAlphaTypeAlphaIsOne                                                                    destAlpha:MPSAlphaTypeAlphaIsOne                                                              backgroundColor:nil                                                               conversionInfo:conversionInfo];  MTLTextureDescriptor *grayTextureDescriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatR16Unorm                                                                                                   width:sourceTexture.width                                                                                                  height:sourceTexture.height                                                                                               mipmapped:false];  grayTextureDescriptor.usage = MTLTextureUsageShaderWrite | MTLTextureUsageShaderRead;  id<MTLTexture> grayTexture = [device newTextureWithDescriptor:grayTextureDescriptor];  [conversion encodeToCommandBuffer:commandBuffer sourceTexture:sourceTexture destinationTexture:grayTexture];      MTLTextureDescriptor *textureDescriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:grayTexture.pixelFormat                                                                                               width:sourceTexture.width                                                                                              height:sourceTexture.height                                                                                           mipmapped:false];  textureDescriptor.usage = MTLTextureUsageShaderWrite | MTLTextureUsageShaderRead;  id<MTLTexture> texture = [device newTextureWithDescriptor:textureDescriptor];    MPSImageLaplacian *imageKernel = [[MPSImageLaplacian alloc] initWithDevice:device];  [imageKernel encodeToCommandBuffer:commandBuffer sourceTexture:grayTexture destinationTexture:texture];      MPSImageStatisticsMeanAndVariance *meanAndVariance = [[MPSImageStatisticsMeanAndVariance alloc] initWithDevice:device];  MTLTextureDescriptor *varianceTextureDescriptor = [MTLTextureDescriptor                                                     texture2DDescriptorWithPixelFormat:MTLPixelFormatR32Float                                                     width:2                                                     height:1                                                     mipmapped:NO];  varianceTextureDescriptor.usage = MTLTextureUsageShaderWrite;  id<MTLTexture> varianceTexture = [device newTextureWithDescriptor:varianceTextureDescriptor];  [meanAndVariance encodeToCommandBuffer:commandBuffer sourceTexture:texture destinationTexture:varianceTexture];      [commandBuffer commit];  [commandBuffer waitUntilCompleted];    union {      float f[2];      unsigned char bytes[8];  } u;    MTLRegion region = MTLRegionMake2D(0, 0, 2, 1);  [varianceTexture getBytes:u.bytes bytesPerRow:2 * 4 fromRegion:region mipmapLevel: 0];    NSLog(@"mean: %f", u.f[0] * 255);  NSLog(@"variance: %f", u.f[1] * 255 * 255);  

It will be great if I get swift representation for this?

https://stackoverflow.com/questions/66558088/objective-c-to-swift-conversion-for-unions March 10, 2021 at 11:51AM