// Vita3K emulator project
// Copyright (C) 2026 Vita3K team
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

#version 450
#extension GL_ARB_separate_shader_objects : enable
#extension GL_ARB_shading_language_420pack : enable
#extension GL_GOOGLE_include_directive : enable

layout(push_constant) uniform viewport
{
	uvec2 offset;
	uvec2 dim;
	uvec2 texture_dim;
	uvec2 output_dim;
};

uvec4 con0;
uvec4 con1;
uvec4 con2;
uvec4 con3;

#define A_GPU 1
#define A_GLSL 1

#define A_HALF
#include "../../../external/GPUOpen/ffx_a.h"
layout(set=0,binding=1) uniform texture2D InputTexture;
layout(set=0,binding=2,rgba16f) uniform image2D OutputTexture;
layout(set=0,binding=3) uniform sampler InputSampler;
#define FSR_EASU_H 1
AH4 FsrEasuRH(AF2 p) { AH4 res = AH4(textureGather(sampler2D(InputTexture,InputSampler), p, 0)); return res; }
AH4 FsrEasuGH(AF2 p) { AH4 res = AH4(textureGather(sampler2D(InputTexture,InputSampler), p, 1)); return res; }
AH4 FsrEasuBH(AF2 p) { AH4 res = AH4(textureGather(sampler2D(InputTexture,InputSampler), p, 2)); return res; }	

#include "../../../external/GPUOpen/ffx_fsr1.h"

void CurrFilter(AU2 pos)
{
	AH3 c;
	FsrEasuH(c, pos, con0, con1, con2, con3);
	imageStore(OutputTexture, ASU2(pos), AH4(c, 1));
}

layout(local_size_x=64) in;
void main()
{
	FsrEasuConOffset(con0, con1, con2, con3, dim.x, dim.y, texture_dim.x, texture_dim.y, output_dim.x, output_dim.y, offset.x, offset.y);
	// Do remapping of local xy in workgroup for a more PS-like swizzle pattern.
	AU2 gxy = ARmp8x8(gl_LocalInvocationID.x) + AU2(gl_WorkGroupID.x << 4u, gl_WorkGroupID.y << 4u);
	CurrFilter(gxy);
	gxy.x += 8u;
	CurrFilter(gxy);
	gxy.y += 8u;
	CurrFilter(gxy);
	gxy.x -= 8u;
	CurrFilter(gxy);
}

