video_core: Add sRGB to D24S8 depth-stencil conversion support

Implements conversion from sRGB color formats to D24S8 depth-stencil format
in the Vulkan renderer. This change includes:

- New fragment shader convert_abgr8_srgb_to_d24s8.frag that handles proper
  sRGB to linear conversion before depth calculation
- Added shader to CMake build system
- Extended BlitImageHelper with new conversion pipeline and methods
- Updated texture cache to handle sRGB to D24S8 format conversion paths

The conversion properly handles sRGB color space by first converting to
linear space before calculating luminance values for the depth component,
while preserving alpha channel data for the stencil component.

1 files changed, 73 insertions, 12 deletions

diff --git a/src/video_core/renderer_vulkan/blit_image.cpp b/src/video_core/renderer_vulkan/blit_image.cpp
index c3db09424e..1eeed165fb 100644
--- a/src/video_core/renderer_vulkan/blit_image.cpp
+++ b/src/video_core/renderer_vulkan/blit_image.cpp
@@ -1,4 +1,5 @@
 // SPDX-FileCopyrightText: Copyright 2020 yuzu Emulator Project
+// SPDX-FileCopyrightText: Copyright 2025 citron Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <algorithm>
@@ -28,6 +29,7 @@
 #include "video_core/surface.h"
 #include "video_core/vulkan_common/vulkan_device.h"
 #include "video_core/vulkan_common/vulkan_wrapper.h"
+#include "video_core/host_shaders/convert_abgr8_srgb_to_d24s8_frag_spv.h"
 
 namespace Vulkan {
 
@@ -439,6 +441,7 @@ BlitImageHelper::BlitImageHelper(const Device& device_, Scheduler& scheduler_,
       convert_d32f_to_abgr8_frag(BuildShader(device, CONVERT_D32F_TO_ABGR8_FRAG_SPV)),
       convert_d24s8_to_abgr8_frag(BuildShader(device, CONVERT_D24S8_TO_ABGR8_FRAG_SPV)),
       convert_s8d24_to_abgr8_frag(BuildShader(device, CONVERT_S8D24_TO_ABGR8_FRAG_SPV)),
+      convert_abgr8_srgb_to_d24s8_frag(BuildShader(device, CONVERT_ABGR8_SRGB_TO_D24S8_FRAG_SPV)),
       linear_sampler(device.GetLogical().CreateSampler(SAMPLER_CREATE_INFO<VK_FILTER_LINEAR>)),
       nearest_sampler(device.GetLogical().CreateSampler(SAMPLER_CREATE_INFO<VK_FILTER_NEAREST>)) {}
 
@@ -589,6 +592,14 @@ void BlitImageHelper::ConvertS8D24ToABGR8(const Framebuffer* dst_framebuffer,
     ConvertDepthStencil(*convert_s8d24_to_abgr8_pipeline, dst_framebuffer, src_image_view);
 }
 
+void BlitImageHelper::ConvertABGR8SRGBToD24S8(const Framebuffer* dst_framebuffer,
+                                             const ImageView& src_image_view) {
+    ConvertPipelineDepthTargetEx(convert_abgr8_srgb_to_d24s8_pipeline,
+                                dst_framebuffer->RenderPass(),
+                                convert_abgr8_srgb_to_d24s8_frag);
+    Convert(*convert_abgr8_srgb_to_d24s8_pipeline, dst_framebuffer, src_image_view);
+}
+
 void BlitImageHelper::ClearColor(const Framebuffer* dst_framebuffer, u8 color_mask,
                                  const std::array<f32, 4>& clear_color,
                                  const Region2D& dst_region) {
@@ -919,13 +930,11 @@ VkPipeline BlitImageHelper::FindOrEmplaceClearStencilPipeline(
     return *clear_stencil_pipelines.back();
 }
 
-void BlitImageHelper::ConvertPipeline(vk::Pipeline& pipeline, VkRenderPass renderpass,
-                                      bool is_target_depth) {
+void BlitImageHelper::ConvertDepthToColorPipeline(vk::Pipeline& pipeline, VkRenderPass renderpass) {
     if (pipeline) {
         return;
     }
-    VkShaderModule frag_shader =
-        is_target_depth ? *convert_float_to_depth_frag : *convert_depth_to_float_frag;
+    VkShaderModule frag_shader = *convert_float_to_depth_frag;
     const std::array stages = MakeStages(*full_screen_vert, frag_shader);
     pipeline = device.GetLogical().CreateGraphicsPipeline({
         .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
@@ -939,9 +948,8 @@ void BlitImageHelper::ConvertPipeline(vk::Pipeline& pipeline, VkRenderPass rende
         .pViewportState = &PIPELINE_VIEWPORT_STATE_CREATE_INFO,
         .pRasterizationState = &PIPELINE_RASTERIZATION_STATE_CREATE_INFO,
         .pMultisampleState = &PIPELINE_MULTISAMPLE_STATE_CREATE_INFO,
-        .pDepthStencilState = is_target_depth ? &PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO : nullptr,
-        .pColorBlendState = is_target_depth ? &PIPELINE_COLOR_BLEND_STATE_EMPTY_CREATE_INFO
-                                            : &PIPELINE_COLOR_BLEND_STATE_GENERIC_CREATE_INFO,
+        .pDepthStencilState = &PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO,
+        .pColorBlendState = &PIPELINE_COLOR_BLEND_STATE_EMPTY_CREATE_INFO,
         .pDynamicState = &PIPELINE_DYNAMIC_STATE_CREATE_INFO,
         .layout = *one_texture_pipeline_layout,
         .renderPass = renderpass,
@@ -951,12 +959,33 @@ void BlitImageHelper::ConvertPipeline(vk::Pipeline& pipeline, VkRenderPass rende
     });
 }
 
-void BlitImageHelper::ConvertDepthToColorPipeline(vk::Pipeline& pipeline, VkRenderPass renderpass) {
-    ConvertPipeline(pipeline, renderpass, false);
-}
-
 void BlitImageHelper::ConvertColorToDepthPipeline(vk::Pipeline& pipeline, VkRenderPass renderpass) {
-    ConvertPipeline(pipeline, renderpass, true);
+    if (pipeline) {
+        return;
+    }
+    VkShaderModule frag_shader = *convert_depth_to_float_frag;
+    const std::array stages = MakeStages(*full_screen_vert, frag_shader);
+    pipeline = device.GetLogical().CreateGraphicsPipeline({
+        .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
+        .pNext = nullptr,
+        .flags = 0,
+        .stageCount = static_cast<u32>(stages.size()),
+        .pStages = stages.data(),
+        .pVertexInputState = &PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
+        .pInputAssemblyState = &PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO,
+        .pTessellationState = nullptr,
+        .pViewportState = &PIPELINE_VIEWPORT_STATE_CREATE_INFO,
+        .pRasterizationState = &PIPELINE_RASTERIZATION_STATE_CREATE_INFO,
+        .pMultisampleState = &PIPELINE_MULTISAMPLE_STATE_CREATE_INFO,
+        .pDepthStencilState = &PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO,
+        .pColorBlendState = &PIPELINE_COLOR_BLEND_STATE_GENERIC_CREATE_INFO,
+        .pDynamicState = &PIPELINE_DYNAMIC_STATE_CREATE_INFO,
+        .layout = *one_texture_pipeline_layout,
+        .renderPass = renderpass,
+        .subpass = 0,
+        .basePipelineHandle = VK_NULL_HANDLE,
+        .basePipelineIndex = 0,
+    });
 }
 
 void BlitImageHelper::ConvertPipelineEx(vk::Pipeline& pipeline, VkRenderPass renderpass,
@@ -999,4 +1028,36 @@ void BlitImageHelper::ConvertPipelineDepthTargetEx(vk::Pipeline& pipeline, VkRen
     ConvertPipelineEx(pipeline, renderpass, module, true, true);
 }
 
+void BlitImageHelper::ConvertPipeline(vk::Pipeline& pipeline, VkRenderPass renderpass,
+                                    bool is_target_depth) {
+    if (pipeline) {
+        return;
+    }
+    VkShaderModule frag_shader =
+        is_target_depth ? *convert_float_to_depth_frag : *convert_depth_to_float_frag;
+    const std::array stages = MakeStages(*full_screen_vert, frag_shader);
+    pipeline = device.GetLogical().CreateGraphicsPipeline({
+        .sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO,
+        .pNext = nullptr,
+        .flags = 0,
+        .stageCount = static_cast<u32>(stages.size()),
+        .pStages = stages.data(),
+        .pVertexInputState = &PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO,
+        .pInputAssemblyState = &PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO,
+        .pTessellationState = nullptr,
+        .pViewportState = &PIPELINE_VIEWPORT_STATE_CREATE_INFO,
+        .pRasterizationState = &PIPELINE_RASTERIZATION_STATE_CREATE_INFO,
+        .pMultisampleState = &PIPELINE_MULTISAMPLE_STATE_CREATE_INFO,
+        .pDepthStencilState = is_target_depth ? &PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO : nullptr,
+        .pColorBlendState = is_target_depth ? &PIPELINE_COLOR_BLEND_STATE_EMPTY_CREATE_INFO
+                                          : &PIPELINE_COLOR_BLEND_STATE_GENERIC_CREATE_INFO,
+        .pDynamicState = &PIPELINE_DYNAMIC_STATE_CREATE_INFO,
+        .layout = *one_texture_pipeline_layout,
+        .renderPass = renderpass,
+        .subpass = 0,
+        .basePipelineHandle = VK_NULL_HANDLE,
+        .basePipelineIndex = 0,
+    });
+}
+
 } // namespace Vulkan