atyuwen

//==============================================================================================================================
// An optimized AMD FSR's EASU implementation for Mobiles
// Based on https://github.com/GPUOpen-Effects/FidelityFX-FSR/blob/master/ffx-fsr/ffx_fsr1.h
// Details can be found: https://atyuwen.github.io/posts/optimizing-fsr/
// Distributed under the MIT License. Copyright (c) 2021 atyuwen.
// -- FsrEasuSampleH should be implemented by calling shader, like following:
//    AH3 FsrEasuSampleH(AF2 p) { return MyTex.SampleLevel(LinearSampler, p, 0).xyz; }
//==============================================================================================================================
 void FsrEasuL(
 out AH3 pix,