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Hi there, I am trying to create a CoreML Custom layer that runs on the GPU, using Objective-C for CoreML setup and Metal for GPU programming. I have created the CoreML model with the custom layer and can successfully execute on the GPU, I wish to create an MTLBuffer from an input MTLTexture in my setup actual GPU execution, although I can't seem to do so, or get access to the memory address to the MTLTexture memory. When defining a custom layer in CoreML to run on the GPU, the following function needs to be defined, with the given prototype; (BOOL) encodeToCommandBuffer:(id<MTLCommandBuffer>)commandBuffer inputs:(NSArray<id<MTLTexture>> *)inputs outputs:(NSArray<id<MTLTexture>> *)outputs error:(NSError *__autoreleasing _Nullable *)error{ // GPU Setup, moving data, encoding, execution and so on here } Here, the inputs are passed as an NSArray of MTLTexture's, we then pass these texture's on to the Metal Shader for computation. My problem is that I want to pass an MTLBuffer to the Metal Shader, which points to the input data, say inputs[0], but I am having troubling copying the input MTLTexture to an MTLBuffer. I have tried using the MTLBlitCommandEncoder to copy the data from the MTLTexture to an MTLBuffer like so; id<MTLBuffer> test_buffer = [command_PSO.device newBufferWithLength:(8) options:MTLResourceStorageModeShared]; id <MTLBlitCommandEncoder> blitCommandEncoder = [commandBuffer blitCommandEncoder]; [blitCommandEncoder copyFromTexture:inputs[0] sourceSlice:0 sourceLevel:0 sourceOrigin:MTLOriginMake(0, 0, 0) sourceSize:MTLSizeMake(1, 1, 1) toBuffer:test_buffer destinationOffset:0 destinationBytesPerRow:8 destinationBytesPerImage:8]; [blitCommandEncoder endEncoding]; The above example should copy a single pixel from the MTLTexture, inputs[0], to the MTLBuffer, test_buffer, but this is not the case. MTLTextures, getBytes also doesn't work as the inputs have MTLResourceStorageModePrivate set. When I inspect the input MTLTexture I note that the attribute buffer = <null> and I'm wondering if this could be an issue since the texture was not created from a buffer, and perhaps doesn't store the address to memory easily, but surely we should be able to get the memory address somewhere? For further reference, here is the input MTLTexture definition; <CaptureMTLTexture: 0x282469500> -> <AGXA14FamilyTexture: 0x133d9bb00> label = <none> textureType = MTLTextureType2DArray pixelFormat = MTLPixelFormatRGBA16Float width = 8 height = 1 depth = 1 arrayLength = 1 mipmapLevelCount = 1 sampleCount = 1 cpuCacheMode = MTLCPUCacheModeDefaultCache storageMode = MTLStorageModePrivate hazardTrackingMode = MTLHazardTrackingModeTracked resourceOptions = MTLResourceCPUCacheModeDefaultCache MTLResourceStorageModePrivate MTLResourceHazardTrackingModeTracked usage = MTLTextureUsageShaderRead MTLTextureUsageShaderWrite shareable = 0 framebufferOnly = 0 purgeableState = MTLPurgeableStateNonVolatile swizzle = [MTLTextureSwizzleRed, MTLTextureSwizzleGreen, MTLTextureSwizzleBlue, MTLTextureSwizzleAlpha] isCompressed = 0 parentTexture = <null> parentRelativeLevel = 0 parentRelativeSlice = 0 buffer = <null> bufferOffset = 0 bufferBytesPerRow = 0 iosurface = 0x0 iosurfacePlane = 0 allowGPUOptimizedContents = YES label = <none>