/******************************************************************************
 * The MIT License (MIT)
 *
 * Copyright (c) 2020-2022 Baldur Karlsson
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/

#if defined(GLES)
#extension GL_OES_sample_variables : require
#elif defined(OPENGL_CORE)
#extension GL_ARB_sample_shading : require
#endif

#include "glsl_globals.h"

#ifdef VULKAN

layout(binding = 0) uniform PRECISION sampler2DArray srcDepthArray;
layout(binding = 1) uniform PRECISION usampler2DArray srcStencilArray;
// binding = 2 used as an image in the colour copy compute shaders

layout(push_constant) uniform multisamplePush
{
  int numMultiSamples;
  int currentSample;
  int currentSlice;
  uint currentStencil;
}
mscopy;

#define numMultiSamples (mscopy.numMultiSamples)
#define currentSample (mscopy.currentSample)
#define currentSlice (mscopy.currentSlice)
#define currentStencil (mscopy.currentStencil)

#else

uniform PRECISION sampler2DArray srcDepthArray;
uniform PRECISION usampler2DArray srcStencilArray;
// binding = 2 used as an image in the colour copy compute shaders

uniform ivec4 mscopy;

#define numMultiSamples (mscopy.x)
#define currentSample (mscopy.y)
#define currentSlice (mscopy.z)
#define currentStencil (uint(mscopy.w))

#endif

void main()
{
  ivec3 srcCoord =
      ivec3(int(gl_FragCoord.x), int(gl_FragCoord.y), currentSlice *numMultiSamples + gl_SampleID);

  if(currentStencil < 256u)
  {
    uint stencil = texelFetch(srcStencilArray, srcCoord, 0).x;

    if(stencil != currentStencil)
      discard;
  }

  gl_FragDepth = texelFetch(srcDepthArray, srcCoord, 0).x;
}
