video_core/opengl: Add FSR upscaling filter to the OpenGL renderer

src/video_core/host_shaders/CMakeLists.txt

@@ -3,12 +3,16 @@
 
 set(FIDELITYFX_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/externals/FidelityFX-FSR/ffx-fsr)
 
-set(GLSL_INCLUDES
-    fidelityfx_fsr.comp
+set(FIDELITYFX_FILES
     ${FIDELITYFX_INCLUDE_DIR}/ffx_a.h
     ${FIDELITYFX_INCLUDE_DIR}/ffx_fsr1.h
 )
 
+set(GLSL_INCLUDES
+    fidelityfx_fsr.comp
+    ${FIDELITYFX_FILES}
+)
+
 set(SHADER_FILES
     astc_decoder.comp
     blit_color_float.frag
@@ -24,6 +28,9 @@ set(SHADER_FILES
     fxaa.vert
     opengl_convert_s8d24.comp
     opengl_copy_bc4.comp
+    opengl_fidelityfx_fsr.frag
+    opengl_fidelityfx_fsr_easu.frag
+    opengl_fidelityfx_fsr_rcas.frag
     opengl_present.frag
     opengl_present.vert
     opengl_present_scaleforce.frag
@@ -118,6 +125,25 @@ foreach(FILENAME IN ITEMS ${SHADER_FILES})
     endif()
 endforeach()
 
+foreach(FILEPATH IN ITEMS ${FIDELITYFX_FILES})
+    get_filename_component(FILENAME ${FILEPATH} NAME)
+    string(REPLACE "." "_" HEADER_NAME ${FILENAME})
+    set(SOURCE_FILE ${FILEPATH})
+    set(SOURCE_HEADER_FILE ${SHADER_DIR}/${HEADER_NAME}.h)
+    add_custom_command(
+        OUTPUT
+            ${SOURCE_HEADER_FILE}
+        COMMAND
+            ${CMAKE_COMMAND} -P ${HEADER_GENERATOR} ${SOURCE_FILE} ${SOURCE_HEADER_FILE} ${INPUT_FILE}
+        MAIN_DEPENDENCY
+            ${SOURCE_FILE}
+        DEPENDS
+            ${INPUT_FILE}
+            # HEADER_GENERATOR should be included here but msbuild seems to assume it's always modified
+    )
+    set(SHADER_HEADERS ${SHADER_HEADERS} ${SOURCE_HEADER_FILE})
+endforeach()
+
 set(SHADER_SOURCES ${SHADER_FILES})
 list(APPEND SHADER_SOURCES ${GLSL_INCLUDES})
 

src/video_core/host_shaders/opengl_fidelityfx_fsr.frag

@@ -0,0 +1,108 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+//!#version 460 core
+#extension GL_ARB_separate_shader_objects : enable
+#extension GL_ARB_shading_language_420pack : enable
+
+#extension GL_AMD_gpu_shader_half_float : enable
+#extension GL_NV_gpu_shader5 : enable
+
+// FidelityFX Super Resolution Sample
+//
+// Copyright (c) 2021 Advanced Micro Devices, Inc. All rights reserved.
+// 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.
+
+layout (location = 0) uniform uvec4 constants[4];
+
+#define A_GPU 1
+#define A_GLSL 1
+
+#ifdef YUZU_USE_FP16
+    #define A_HALF
+#endif
+#include "ffx_a.h"
+
+#ifndef YUZU_USE_FP16
+    layout (binding=0) uniform sampler2D InputTexture;
+    #if USE_EASU
+        #define FSR_EASU_F 1
+        AF4 FsrEasuRF(AF2 p) { AF4 res = textureGather(InputTexture, p, 0); return res; }
+        AF4 FsrEasuGF(AF2 p) { AF4 res = textureGather(InputTexture, p, 1); return res; }
+        AF4 FsrEasuBF(AF2 p) { AF4 res = textureGather(InputTexture, p, 2); return res; }
+    #endif
+    #if USE_RCAS
+        #define FSR_RCAS_F
+        AF4 FsrRcasLoadF(ASU2 p) { return texelFetch(InputTexture, ASU2(p), 0); }
+        void FsrRcasInputF(inout AF1 r, inout AF1 g, inout AF1 b) {}
+    #endif
+#else
+    layout (binding=0) uniform sampler2D InputTexture;
+    #if USE_EASU
+        #define FSR_EASU_H 1
+        AH4 FsrEasuRH(AF2 p) { AH4 res = AH4(textureGather(InputTexture, p, 0)); return res; }
+        AH4 FsrEasuGH(AF2 p) { AH4 res = AH4(textureGather(InputTexture, p, 1)); return res; }
+        AH4 FsrEasuBH(AF2 p) { AH4 res = AH4(textureGather(InputTexture, p, 2)); return res; }
+    #endif
+    #if USE_RCAS
+        #define FSR_RCAS_H
+        AH4 FsrRcasLoadH(ASW2 p) { return AH4(texelFetch(InputTexture, ASU2(p), 0)); }
+        void FsrRcasInputH(inout AH1 r,inout AH1 g,inout AH1 b){}
+    #endif
+#endif
+
+#include "ffx_fsr1.h"
+
+#if USE_RCAS
+    layout(location = 0) in vec2 frag_texcoord;
+#endif
+layout (location = 0) out vec4 frag_color;
+
+void CurrFilter(AU2 pos)
+{
+#if USE_EASU
+    #ifndef YUZU_USE_FP16
+        AF3 c;
+        FsrEasuF(c, pos, constants[0], constants[1], constants[2], constants[3]);
+        frag_color = AF4(c, 1.0);
+    #else
+        AH3 c;
+        FsrEasuH(c, pos, constants[0], constants[1], constants[2], constants[3]);
+        frag_color = AH4(c, 1.0);
+    #endif
+#endif
+#if USE_RCAS
+    #ifndef YUZU_USE_FP16
+        AF3 c;
+        FsrRcasF(c.r, c.g, c.b, pos, constants[0]);
+        frag_color = AF4(c, 1.0);
+    #else
+        AH3 c;
+        FsrRcasH(c.r, c.g, c.b, pos, constants[0]);
+        frag_color = AH4(c, 1.0);
+    #endif
+#endif
+}
+
+void main()
+{
+#if USE_RCAS
+    CurrFilter(AU2(frag_texcoord * vec2(textureSize(InputTexture, 0))));
+#else
+    CurrFilter(AU2(gl_FragCoord.xy));
+#endif
+}

src/video_core/host_shaders/opengl_fidelityfx_fsr_easu.frag

@@ -0,0 +1,9 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#version 460 core
+#extension GL_GOOGLE_include_directive : enable
+
+#define USE_EASU 1
+
+#include "opengl_fidelityfx_fsr.frag"

src/video_core/host_shaders/opengl_fidelityfx_fsr_rcas.frag

@@ -0,0 +1,9 @@
+// SPDX-FileCopyrightText: Copyright 2023 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#version 460 core
+#extension GL_GOOGLE_include_directive : enable
+
+#define USE_RCAS 1
+
+#include "opengl_fidelityfx_fsr.frag"