code: Add texture sampling option

* This replaces the nearest neighbour filter that shouldn't have existed in the first place

src/citra_qt/configuration/configure_enhancements.ui

@@ -184,11 +184,6 @@
              <string>Bicubic</string>
             </property>
            </item>
-           <item>
-            <property name="text">
-             <string>Nearest Neighbor</string>
-            </property>
-           </item>
            <item>
             <property name="text">
              <string>ScaleForce</string>
@@ -199,11 +194,11 @@
              <string>xBRZ</string>
             </property>
            </item>
-            <item>
-              <property name="text">
-                <string>MMPX</string>
-              </property>
-            </item>
+           <item>
+            <property name="text">
+             <string>MMPX</string>
+            </property>
+           </item>
           </widget>
          </item>
         </layout>

src/citra_qt/configuration/configure_graphics.cpp

@@ -71,11 +71,17 @@ void ConfigureGraphics::SetConfiguration() {
                                           !Settings::values.physical_device.UsingGlobal());
         ConfigurationShared::SetPerGameSetting(ui->physical_device_combo,
                                                &Settings::values.physical_device);
+        ConfigurationShared::SetPerGameSetting(ui->texture_sampling_combobox,
+                                               &Settings::values.texture_sampling);
+        ConfigurationShared::SetHighlight(ui->widget_texture_sampling,
+                                          !Settings::values.texture_sampling.UsingGlobal());
     } else {
         ui->graphics_api_combo->setCurrentIndex(
             static_cast<int>(Settings::values.graphics_api.GetValue()));
         ui->physical_device_combo->setCurrentIndex(
             static_cast<int>(Settings::values.physical_device.GetValue()));
+        ui->texture_sampling_combobox->setCurrentIndex(
+            static_cast<int>(Settings::values.texture_sampling.GetValue()));
     }
 
     ui->toggle_hw_shader->setChecked(Settings::values.use_hw_shader.GetValue());
@@ -106,6 +112,8 @@ void ConfigureGraphics::ApplyConfiguration() {
                                              use_hw_shader);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.shaders_accurate_mul,
                                              ui->toggle_accurate_mul, shaders_accurate_mul);
+    ConfigurationShared::ApplyPerGameSetting(&Settings::values.texture_sampling,
+                                             ui->texture_sampling_combobox);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.use_disk_shader_cache,
                                              ui->toggle_disk_shader_cache, use_disk_shader_cache);
     ConfigurationShared::ApplyPerGameSetting(&Settings::values.use_vsync_new, ui->toggle_vsync_new,
@@ -132,6 +140,7 @@ void ConfigureGraphics::SetupPerGameUI() {
                                          Settings::values.use_vsync_new.UsingGlobal());
         ui->toggle_async_shaders->setEnabled(
             Settings::values.async_shader_compilation.UsingGlobal());
+        ui->widget_texture_sampling->setEnabled(Settings::values.texture_sampling.UsingGlobal());
         ui->toggle_async_present->setEnabled(Settings::values.async_presentation.UsingGlobal());
         ui->graphics_api_combo->setEnabled(Settings::values.graphics_api.UsingGlobal());
         ui->physical_device_combo->setEnabled(Settings::values.physical_device.UsingGlobal());
@@ -148,6 +157,10 @@ void ConfigureGraphics::SetupPerGameUI() {
         ui->physical_device_combo, ui->physical_device_group,
         static_cast<u32>(Settings::values.physical_device.GetValue(true)));
 
+    ConfigurationShared::SetColoredComboBox(
+        ui->texture_sampling_combobox, ui->widget_texture_sampling,
+        static_cast<int>(Settings::values.texture_sampling.GetValue(true)));
+
     ConfigurationShared::SetColoredTristate(ui->toggle_hw_shader, Settings::values.use_hw_shader,
                                             use_hw_shader);
     ConfigurationShared::SetColoredTristate(

src/citra_qt/configuration/configure_graphics.ui

@@ -212,6 +212,53 @@
       <string>Advanced</string>
      </property>
      <layout class="QVBoxLayout" name="verticalLayout_2">
+      <item>
+       <widget class="QWidget" name="widget_texture_sampling" native="true">
+        <layout class="QHBoxLayout" name="horizontalLayout_2">
+         <property name="leftMargin">
+          <number>0</number>
+         </property>
+         <property name="topMargin">
+          <number>0</number>
+         </property>
+         <property name="rightMargin">
+          <number>0</number>
+         </property>
+         <property name="bottomMargin">
+          <number>0</number>
+         </property>
+         <item>
+          <widget class="QLabel" name="texture_sampling_label">
+           <property name="toolTip">
+            <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;Overrides the sampling filter used by games. This can be useful in certain cases with poorly behaved games when upscaling. If unsure set this to Game Controlled&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+           </property>
+           <property name="text">
+            <string>Texture Sampling</string>
+           </property>
+          </widget>
+         </item>
+         <item>
+          <widget class="QComboBox" name="texture_sampling_combobox">
+           <item>
+            <property name="text">
+             <string>Game Controlled</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Nearest Neighbor</string>
+            </property>
+           </item>
+           <item>
+            <property name="text">
+             <string>Linear</string>
+            </property>
+           </item>
+          </widget>
+         </item>
+        </layout>
+       </widget>
+      </item>
       <item>
        <widget class="QCheckBox" name="toggle_disk_shader_cache">
         <property name="toolTip">

src/common/settings.cpp

@@ -46,8 +46,6 @@ std::string_view GetTextureFilterName(TextureFilter filter) {
         return "Anime4K";
     case TextureFilter::Bicubic:
         return "Bicubic";
-    case TextureFilter::NearestNeighbor:
-        return "NearestNeighbor";
     case TextureFilter::ScaleForce:
         return "ScaleForce";
     case TextureFilter::xBRZ:
@@ -59,6 +57,19 @@ std::string_view GetTextureFilterName(TextureFilter filter) {
     }
 }
 
+std::string_view GetTextureSamplingName(TextureSampling sampling) {
+    switch (sampling) {
+    case TextureSampling::GameControlled:
+        return "GameControlled";
+    case TextureSampling::NearestNeighbor:
+        return "NearestNeighbor";
+    case TextureSampling::Linear:
+        return "Linear";
+    default:
+        return "Invalid";
+    }
+}
+
 } // Anonymous namespace
 
 Values values = {};
@@ -87,6 +98,8 @@ void LogSettings() {
     log_setting("Renderer_PostProcessingShader", values.pp_shader_name.GetValue());
     log_setting("Renderer_FilterMode", values.filter_mode.GetValue());
     log_setting("Renderer_TextureFilter", GetTextureFilterName(values.texture_filter.GetValue()));
+    log_setting("Renderer_TextureSampling",
+                GetTextureSamplingName(values.texture_sampling.GetValue()));
     log_setting("Stereoscopy_Render3d", values.render_3d.GetValue());
     log_setting("Stereoscopy_Factor3d", values.factor_3d.GetValue());
     log_setting("Stereoscopy_MonoRenderOption", values.mono_render_option.GetValue());
@@ -175,6 +188,7 @@ void RestoreGlobalState(bool is_powered_on) {
     values.resolution_factor.SetGlobal(true);
     values.frame_limit.SetGlobal(true);
     values.texture_filter.SetGlobal(true);
+    values.texture_sampling.SetGlobal(true);
     values.layout_option.SetGlobal(true);
     values.swap_screen.SetGlobal(true);
     values.upright_screen.SetGlobal(true);

src/common/settings.h

@@ -72,10 +72,15 @@ enum class TextureFilter : u32 {
     None = 0,
     Anime4K = 1,
     Bicubic = 2,
-    NearestNeighbor = 3,
-    ScaleForce = 4,
-    xBRZ = 5,
-    MMPX = 6
+    ScaleForce = 3,
+    xBRZ = 4,
+    MMPX = 5,
+};
+
+enum class TextureSampling : u32 {
+    GameControlled = 0,
+    NearestNeighbor = 1,
+    Linear = 2,
 };
 
 namespace NativeButton {
@@ -451,6 +456,8 @@ struct Values {
     SwitchableSetting<u32, true> resolution_factor{1, 0, 10, "resolution_factor"};
     SwitchableSetting<u16, true> frame_limit{100, 0, 1000, "frame_limit"};
     SwitchableSetting<TextureFilter> texture_filter{TextureFilter::None, "texture_filter"};
+    SwitchableSetting<TextureSampling> texture_sampling{TextureSampling::GameControlled,
+                                                        "texture_sampling"};
 
     SwitchableSetting<LayoutOption> layout_option{LayoutOption::Default, "layout_option"};
     SwitchableSetting<bool> swap_screen{false, "swap_screen"};

src/video_core/host_shaders/CMakeLists.txt

@@ -7,7 +7,6 @@ set(SHADER_FILES
     format_reinterpreter/rgba4_to_rgb5a1.frag
     format_reinterpreter/vulkan_d24s8_to_rgba8.comp
     texture_filtering/bicubic.frag
-    texture_filtering/nearest_neighbor.frag
     texture_filtering/refine.frag
     texture_filtering/scale_force.frag
     texture_filtering/xbrz_freescale.frag

src/video_core/host_shaders/texture_filtering/nearest_neighbor.frag

@@ -1,15 +0,0 @@
-// Copyright 2023 Citra Emulator Project
-// Licensed under GPLv2 or any later version
-// Refer to the license.txt file included.
-
-//? #version 430 core
-precision mediump float;
-
-layout(location = 0) in vec2 tex_coord;
-layout(location = 0) out vec4 frag_color;
-
-layout(binding = 2) uniform sampler2D input_texture;
-
-void main() {
-    frag_color = texture(input_texture, tex_coord);
-}

src/video_core/rasterizer_cache/rasterizer_cache.h

@@ -361,10 +361,25 @@ typename T::Sampler& RasterizerCache<T>::GetSampler(SamplerId sampler_id) {
 template <class T>
 typename T::Sampler& RasterizerCache<T>::GetSampler(
     const Pica::TexturingRegs::TextureConfig& config) {
+    using TextureFilter = Pica::TexturingRegs::TextureConfig::TextureFilter;
+
+    const auto get_filter = [](TextureFilter filter) {
+        switch (Settings::values.texture_sampling.GetValue()) {
+        case Settings::TextureSampling::GameControlled:
+            return filter;
+        case Settings::TextureSampling::NearestNeighbor:
+            return TextureFilter::Nearest;
+        case Settings::TextureSampling::Linear:
+            return TextureFilter::Linear;
+        default:
+            return filter;
+        }
+    };
+
     const SamplerParams params = {
-        .mag_filter = config.mag_filter,
-        .min_filter = config.min_filter,
-        .mip_filter = config.mip_filter,
+        .mag_filter = get_filter(config.mag_filter),
+        .min_filter = get_filter(config.min_filter),
+        .mip_filter = get_filter(config.mip_filter),
         .wrap_s = config.wrap_s,
         .wrap_t = config.wrap_t,
         .border_color = config.border_color.raw,

src/video_core/renderer_opengl/gl_blit_helper.cpp

@@ -15,7 +15,6 @@
 #include "video_core/host_shaders/full_screen_triangle_vert.h"
 #include "video_core/host_shaders/texture_filtering/bicubic_frag.h"
 #include "video_core/host_shaders/texture_filtering/mmpx_frag.h"
-#include "video_core/host_shaders/texture_filtering/nearest_neighbor_frag.h"
 #include "video_core/host_shaders/texture_filtering/refine_frag.h"
 #include "video_core/host_shaders/texture_filtering/scale_force_frag.h"
 #include "video_core/host_shaders/texture_filtering/x_gradient_frag.h"
@@ -58,7 +57,6 @@ BlitHelper::BlitHelper(const Driver& driver_)
     : driver{driver_}, linear_sampler{CreateSampler(GL_LINEAR)},
       nearest_sampler{CreateSampler(GL_NEAREST)}, bicubic_program{CreateProgram(
                                                       HostShaders::BICUBIC_FRAG)},
-      nearest_program{CreateProgram(HostShaders::NEAREST_NEIGHBOR_FRAG)},
       scale_force_program{CreateProgram(HostShaders::SCALE_FORCE_FRAG)},
       xbrz_program{CreateProgram(HostShaders::XBRZ_FREESCALE_FRAG)},
       mmpx_program{CreateProgram(HostShaders::MMPX_FRAG)}, gradient_x_program{CreateProgram(
@@ -175,9 +173,6 @@ bool BlitHelper::Filter(Surface& surface, const VideoCore::TextureBlit& blit) {
     case TextureFilter::Bicubic:
         FilterBicubic(surface, blit);
         break;
-    case TextureFilter::NearestNeighbor:
-        FilterNearest(surface, blit);
-        break;
     case TextureFilter::ScaleForce:
         FilterScaleForce(surface, blit);
         break;
@@ -257,14 +252,6 @@ void BlitHelper::FilterBicubic(Surface& surface, const VideoCore::TextureBlit& b
     Draw(bicubic_program, surface.Handle(), draw_fbo.handle, blit.dst_level, blit.dst_rect);
 }
 
-void BlitHelper::FilterNearest(Surface& surface, const VideoCore::TextureBlit& blit) {
-    const OpenGLState prev_state = OpenGLState::GetCurState();
-    SCOPE_EXIT({ prev_state.Apply(); });
-    state.texture_units[2].texture_2d = surface.Handle(0);
-    SetParams(nearest_program, surface.RealExtent(false), blit.src_rect);
-    Draw(nearest_program, surface.Handle(), draw_fbo.handle, blit.dst_level, blit.dst_rect);
-}
-
 void BlitHelper::FilterScaleForce(Surface& surface, const VideoCore::TextureBlit& blit) {
     const OpenGLState prev_state = OpenGLState::GetCurState();
     SCOPE_EXIT({ prev_state.Apply(); });

src/video_core/renderer_opengl/gl_blit_helper.h

@@ -33,20 +33,13 @@ public:
 
 private:
     void FilterAnime4K(Surface& surface, const VideoCore::TextureBlit& blit);
-
     void FilterBicubic(Surface& surface, const VideoCore::TextureBlit& blit);
-
-    void FilterNearest(Surface& surface, const VideoCore::TextureBlit& blit);
-
     void FilterScaleForce(Surface& surface, const VideoCore::TextureBlit& blit);
-
     void FilterXbrz(Surface& surface, const VideoCore::TextureBlit& blit);
-
     void FilterMMPX(Surface& surface, const VideoCore::TextureBlit& blit);
 
     void SetParams(OGLProgram& program, const VideoCore::Extent& src_extent,
                    Common::Rectangle<u32> src_rect);
-
     void Draw(OGLProgram& program, GLuint dst_tex, GLuint dst_fbo, u32 dst_level,
               Common::Rectangle<u32> dst_rect);
 
@@ -59,7 +52,6 @@ private:
     OGLSampler nearest_sampler;
 
     OGLProgram bicubic_program;
-    OGLProgram nearest_program;
     OGLProgram scale_force_program;
     OGLProgram xbrz_program;
     OGLProgram mmpx_program;

src/video_core/renderer_vulkan/vk_blit_helper.h

@@ -35,10 +35,7 @@ public:
                        const VideoCore::BufferTextureCopy& copy);
 
 private:
-    /// Creates compute pipelines used for blit
     vk::Pipeline MakeComputePipeline(vk::ShaderModule shader, vk::PipelineLayout layout);
-
-    /// Creates graphics pipelines used for blit
     vk::Pipeline MakeDepthStencilBlitPipeline();
 
 private: