metal

My SCNView is using Metal as the rendering API and I would like to know if there's a way to grab the rendered scene as a MTLTexture without having to use a separate SCNRenderer ? Performance drops when I'm trying to both display the scene via the SCNView and re-rendering the scene offscreen to a MTLTexture via a SCNRenderer (I'm trying to grab the output every frame). SCNView gives me access to the MTLDevice , MTLRenderCommandEncoder , and MTLCommandQueue that it uses, but not to the underlying MTLRenderPassDescriptor that I would need in order to get the MTLTexture (via renderPassDescriptor

When I capture the contents of an MTKView into a UIImage, the resulting image looks qualitatively different, as shown below: The code I use to generate the UIImage is as follows: let kciOptions = [kCIContextWorkingColorSpace: CGColorSpace(name: CGColorSpace.sRGB)!, kCIContextOutputPremultiplied: true, kCIContextUseSoftwareRenderer: false] as [String : Any] let lastDrawableDisplayed = self.currentDrawable! // needed to hold the last drawable presented to screen drawingUIView.image = UIImage(ciImage: CIImage(mtlTexture: lastDrawableDisplayed.texture, options: kciOptions)!) Since I don't modify

I'm trying to create a custom SCNGeometry in the form of a plane with custom shape, which could be placed in an ARKit session. I'm using the option SCNGeometryPrimitiveTypePolygon in the following method which seems to work fine: extension SCNGeometry { static func polygonPlane(vertices: [SCNVector3]) -> SCNGeometry { var indices: [Int32] = [Int32(vertices.count)] var index: Int32 = 0 for _ in vertices { indices.append(index) index += 1 } let vertexSource = SCNGeometrySource(vertices: vertices) let indexData = Data(bytes: indices, count: indices.count * MemoryLayout<Int32>.size) let element =

I am trying to create a framework that works with METAL Api (iOS). I am pretty new to this platform and I would like to know how to build the framework to work with .metal files (I am building a static lib, not dynamic). Should they be a part of the .a file, or as a resource files in the framework bundle? Or is there an other way to do that? Thanks. Update: For those who tackle this - I ended up following warrenm's 1's suggested option - converted the .metal file into a string and calling newLibraryWithSource:options:error: . Although it is not the best in performance it allowed me to ship

I am trying to compute sum of large array in parallel with metal swift. Is there a god way to do it? My plane was that I divide my array to sub arrays, compute sum of one sub arrays in parallel and then when parallel computation is finished compute sum of sub sums. for example if I have array = [a0,....an] I divide array in sub arrays : array_1 = [a_0,...a_i], array_2 = [a_i+1,...a_2i], .... array_n/i = [a_n-1, ... a_n] sums for this arrays is computed in parallel and I get sum_1, sum_2, sum_3, ... sum_n/1 at the end just compute sum of sub sums. I create application which run my metal shader,

To avoid writing to a constant buffer from both the gpu and cpu at the same time, Apple recommends using a triple-buffered system with the help of a semaphore to prevent the cpu getting too far ahead of the gpu (this is fine and covered in at least three Metal videos now at this stage). However, when the constant resource is an MTLTexture and the AVCaptureVideoDataOutput delegate runs separately than the rendering loop (CADisplaylink), how can a similar triple-buffered system (as used in Apple’s sample code MetalVideoCapture) guarantee synchronization? Screen tearing (texture tearing) can be