Ray Tracing, Apple Metal, Swift Programming, Gpu Rendering, Wwdc 2020.
computeEncoder?.dispatchThreads(threadsPerGrid, threadsPerThreadgroup: threadPerThreadgroup) //6 Off to the GPU computeEncoder?.endEncoding() computeEncoder?.popDebugGroup() commandBuffer?.commit() commandBuffer?.waitUntilCompleted() let end = DispatchTime.now() // <<<<<<<<<< end time let nanoTime