Use fixed kernel & tune shadow height & remove translation string

data/gui/dialogs/custom_video_settings.stkgui

@@ -103,14 +103,6 @@
                 <spacer width="10" height="10"/>
                 <label text="Ambient occlusion" I18N="Video settings"/>
             </div>
-
-            <spacer height="4" width="10" />
-
-            <div layout="horizontal-row" proportion="1" height="fit">
-                <checkbox id="pcss"/>
-                <spacer width="10" height="10"/>
-                <label text="Soft shadows" I18N="Video settings"/>
-            </div>
         </div>
 
         <spacer height="4" width="10" />

data/shaders/sunlightshadowpcss.frag

@@ -1,3 +1,4 @@
+// Implementation from https://github.com/google/filament/blob/main/shaders/src/surface_shadowing.fs
 uniform sampler2D ntex;
 #if defined(GL_ES) && defined(GL_FRAGMENT_PRECISION_HIGH)
 uniform highp sampler2D dtex;
@@ -58,11 +59,16 @@ vec2 vogel_disk_16[16] = vec2[](
     vec2(-0.1133270115046468, -0.9490025827627441)
 );
 
-vec2 vogel_disk_4[4] = vec2[](
-	vec2(0.21848650099008202, -0.09211370200809937),
-	vec2(-0.5866112654782878, 0.32153793477769893),
-	vec2(-0.06595078555407359, -0.879656059066481),
-	vec2(0.43407555004227927, 0.6502318262968816)
+// https://learn.microsoft.com/en-us/windows/win32/api/d3d11/ne-d3d11-d3d11_standard_multisample_quality_levels?redirectedfrom=MSDN
+vec2 sample_point_pos[8] = vec2[](
+	vec2( 0.125, -0.375),
+    vec2(-0.125,  0.375),
+    vec2( 0.625,  0.125),
+    vec2(-0.375, -0.625),
+    vec2(-0.625,  0.625),
+    vec2(-0.875, -0.125),
+    vec2( 0.375,  0.875),
+    vec2( 0.875, -0.875)
 );
 
 float interleavedGradientNoise(vec2 w)
@@ -95,27 +101,26 @@ mat2 getRandomRotationMatrix(vec2 fragCoord)
 void blockerSearchAndFilter(out float occludedCount, out float z_occSum,
         vec2 uv, float z_rec, uint layer, vec2 filterRadii, mat2 R, vec2 dz_duv)
 {
-    occludedCount = 0.0;
-    z_occSum = 0.0;
-    for (uint i = 0u; i < 4u; i++)
+    // Make sure no light leaking
+    float z_occ = texture(shadowtexdepth, vec3(uv, float(layer))).r;
+    float dz = z_rec - z_occ;
+    float occluded = 0.01 * step(0., dz);
+    occludedCount = occluded;
+    z_occSum = z_occ * occluded;
+
+    for (uint i = 0u; i < 8u; i++)
     {
-        vec2 duv = R * (vogel_disk_4[i] * filterRadii);
+        vec2 duv = R * sample_point_pos[i] * filterRadii;
         vec2 tc = clamp(uv + duv, vec2(0.), vec2(1.));
-
-        float z_occ = texture(shadowtexdepth, vec3(tc, float(layer))).r;
-
         // receiver plane depth bias
         float z_bias = dot(dz_duv, duv);
+
+        float z_occ = texture(shadowtexdepth, vec3(tc, float(layer))).r;
         float dz = z_rec - z_occ; // dz>0 when blocker is between receiver and light
         float occluded = step(z_bias, dz);
         occludedCount += occluded;
         z_occSum += z_occ * occluded;
     }
-    float z_occ = texture(shadowtexdepth, vec3(uv, float(layer))).r;
-    float dz = z_rec - z_occ;
-    float occluded = step(0., dz);
-    occludedCount += occluded;
-    z_occSum += z_occ * occluded;
 }
 
 float filterPCSS(vec2 uv, float z_rec, uint layer,
@@ -152,8 +157,9 @@ float getShadowFactor(vec3 position, vec3 bbox, vec2 dz_duv, uint layer)
     }
 
     float penumbraRatio = 1.0 - z_occSum / occludedCount / position.z;
+    vec2 radius = max(penumbra / bbox.xy * penumbraRatio, vec2(0.5 / shadow_res));
 
-    float percentageOccluded = filterPCSS(position.xy, position.z, layer, penumbra / bbox.xy * penumbraRatio, R, dz_duv);
+    float percentageOccluded = filterPCSS(position.xy, position.z, layer, radius, R, dz_duv);
 
     return percentageOccluded;
 }

src/config/user_config.hpp

@@ -1013,14 +1013,14 @@ namespace UserConfigParams
             PARAM_DEFAULT(BoolUserConfigParam(true,
                            "light_scatter", &m_graphics_quality,
                            "Enable light scattering shaders") );
-    PARAM_PREFIX BoolUserConfigParam         m_pcss
-            PARAM_DEFAULT(BoolUserConfigParam(false,
-                           "pcss", &m_graphics_quality,
-                           "Enable Percentage Closer Soft Shadows (needs high shadow resolution)") );
     PARAM_PREFIX IntUserConfigParam          m_shadows_resolution
             PARAM_DEFAULT( IntUserConfigParam(0,
                            "shadows_resolution", &m_graphics_quality,
                            "Shadow resolution (0 = disabled") );
+    PARAM_PREFIX IntUserConfigParam          m_pcss_threshold
+            PARAM_DEFAULT( IntUserConfigParam(2048,
+                           "pcss_threshold", &m_graphics_quality,
+                           "Enable Percentage Closer Soft Shadows when shadow resolution is higher than this value") );
     PARAM_PREFIX BoolUserConfigParam          m_degraded_IBL
         PARAM_DEFAULT(BoolUserConfigParam(true,
         "Degraded_IBL", &m_graphics_quality,

src/graphics/lighting_passes.cpp

@@ -514,7 +514,7 @@ void LightingPasses::renderLights(  bool has_shadow,
             glDisable(GL_DEPTH_TEST);
             glBlendFunc(GL_ONE, GL_ONE);
             glBlendEquation(GL_FUNC_ADD);
-            if (UserConfigParams::m_pcss)
+            if (UserConfigParams::m_pcss_threshold <= UserConfigParams::m_shadows_resolution)
             {
                 ShadowedSunLightShaderPCSS::getInstance()->render(normal_depth_texture,
                                                                   depth_stencil_texture,

src/graphics/shadow_matrices.cpp

@@ -176,12 +176,14 @@ core::matrix4 ShadowMatrices::getTightestFitOrthoProj(const core::matrix4 &trans
     // Prevent Matrix without extend
     if (left == right || up == down)
         return tmp_matrix;
+
+    float vnear = std::min((zmax + zmin) / 2 - 200, zmin); // 200m above karts
     tmp_matrix.buildProjectionMatrixOrthoLH(left, right,
         down, up,
-        zmin - 100, zmax);
+        vnear, zmax);
     bounding_box_extent.X = right - left;
     bounding_box_extent.Y = down - up;
-    bounding_box_extent.Z = zmax - zmin + 100;
+    bounding_box_extent.Z = zmax - vnear;
     return tmp_matrix;
 }   // getTightestFitOrthoProj
 

src/states_screens/dialogs/custom_video_settings.cpp

@@ -116,7 +116,6 @@ void CustomVideoSettingsDialog::beforeAddingWidgets()
     getWidget<CheckBoxWidget>("ssao")->setState(UserConfigParams::m_ssao);
     getWidget<CheckBoxWidget>("bloom")->setState(UserConfigParams::m_bloom);
     getWidget<CheckBoxWidget>("lightscattering")->setState(UserConfigParams::m_light_scatter);
-    getWidget<CheckBoxWidget>("pcss")->setState(UserConfigParams::m_pcss);
     if (CVS->isEXTTextureCompressionS3TCUsable())
     {
         getWidget<CheckBoxWidget>("texture_compression")->setState(UserConfigParams::m_texture_compression);
@@ -190,9 +189,6 @@ GUIEngine::EventPropagation CustomVideoSettingsDialog::processEvent(const std::s
             UserConfigParams::m_light_scatter =
                 advanced_pipeline && getWidget<CheckBoxWidget>("lightscattering")->getState();
 
-            UserConfigParams::m_pcss =
-                advanced_pipeline && getWidget<CheckBoxWidget>("pcss")->getState();
-
             UserConfigParams::m_texture_compression =
                 getWidget<CheckBoxWidget>("texture_compression")->getState();
 #ifndef SERVER_ONLY
@@ -235,10 +231,6 @@ GUIEngine::EventPropagation CustomVideoSettingsDialog::processEvent(const std::s
     {
         updateActivation();
     }
-    else if (eventSource == "shadows")
-    {
-        updateActivation();
-    }
 #endif
     return GUIEngine::EVENT_LET;
 }   // processEvent
@@ -249,7 +241,6 @@ void CustomVideoSettingsDialog::updateActivation()
 {
 #ifndef SERVER_ONLY
     bool light = getWidget<CheckBoxWidget>("dynamiclight")->getState();
-    bool shadows = getWidget<SpinnerWidget>("shadows")->getValue();
     if (!CVS->isGLSL())
     {
         getWidget<CheckBoxWidget>("dynamiclight")->setActive(false);
@@ -267,6 +258,5 @@ void CustomVideoSettingsDialog::updateActivation()
     getWidget<CheckBoxWidget>("glow")->setActive(light);
     getWidget<CheckBoxWidget>("bloom")->setActive(light);
     getWidget<CheckBoxWidget>("lightscattering")->setActive(light);
-    getWidget<CheckBoxWidget>("pcss")->setActive(light & shadows);
 #endif
 }   // updateActivation

src/states_screens/options/options_screen_video.cpp

@@ -43,55 +43,55 @@ void OptionsScreenVideo::initPresets()
         false /* light */, 0 /* shadow */, false /* bloom */, false /* lightshaft */,
         false /* glow */, false /* mlaa */, false /* ssao */, false /* light scatter */,
         false /* animatedCharacters */, 1 /* particles */, 0 /* image_quality */,
-        true /* degraded IBL */, 0 /* Geometry Detail */, false /* pcss */
+        true /* degraded IBL */, 0 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 2
     ({
         false /* light */, 0 /* shadow */, false /* bloom */, false /* lightshaft */,
         false /* glow */, false /* mlaa */, false /* ssao */, false /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 1 /* image_quality */,
-        true /* degraded IBL */, 1 /* Geometry Detail */, false /* pcss */
+        true /* degraded IBL */, 1 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 3
     ({
         true /* light */, 0 /* shadow */, false /* bloom */, false /* lightshaft */,
         false /* glow */, false /* mlaa */, false /* ssao */, false /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 1 /* image_quality */,
-        true /* degraded IBL */, 2 /* Geometry Detail */, false /* pcss */
+        true /* degraded IBL */, 2 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 4
     ({
         true /* light */, 0 /* shadow */, false /* bloom */, true /* lightshaft */,
         true /* glow */, true /* mlaa */, false /* ssao */, true /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 2 /* image_quality */,
-        false /* degraded IBL */, 3 /* Geometry Detail */, false /* pcss */
+        false /* degraded IBL */, 3 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 5
     ({
         true /* light */, 512 /* shadow */, true /* bloom */, true /* lightshaft */,
         true /* glow */, true /* mlaa */, false /* ssao */, true /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 3 /* image_quality */,
-        false /* degraded IBL */, 3 /* Geometry Detail */, false /* pcss */
+        false /* degraded IBL */, 3 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 6
     ({
         true /* light */, 1024 /* shadow */, true /* bloom */, true /* lightshaft */,
         true /* glow */, true /* mlaa */, true /* ssao */, true /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 3 /* image_quality */,
-        false /* degraded IBL */, 4 /* Geometry Detail */, false /* pcss */
+        false /* degraded IBL */, 4 /* Geometry Detail */
     });
 
     m_presets.push_back // Level 7
     ({
         true /* light */, 2048 /* shadow */, true /* bloom */, true /* lightshaft */,
         true /* glow */, true /* mlaa */, true /* ssao */, true /* light scatter */,
         true /* animatedCharacters */, 2 /* particles */, 3 /* image_quality */,
-        false /* degraded IBL */, 5 /* Geometry Detail */, true /* pcss */
+        false /* degraded IBL */, 5 /* Geometry Detail */
     });
 
     m_blur_presets.push_back
@@ -358,8 +358,7 @@ void OptionsScreenVideo::updateGfxSlider()
             m_presets[l].degraded_ibl == UserConfigParams::m_degraded_IBL &&
             m_presets[l].geometry_detail == (UserConfigParams::m_geometry_level == 0 ? 2 :
                                              UserConfigParams::m_geometry_level == 2 ? 0 :
-                                             UserConfigParams::m_geometry_level) &&
-            m_presets[l].pcss == UserConfigParams::m_pcss)
+                                             UserConfigParams::m_geometry_level))
         {
             gfx->setValue(l + 1);
             found = true;
@@ -498,9 +497,6 @@ void OptionsScreenVideo::updateTooltip()
     //I18N: in graphical options
     tooltip = tooltip + L"\n" + _("Ambient occlusion: %s",
         UserConfigParams::m_ssao ? enabled : disabled);
-    //I18N: in graphical options
-    tooltip = tooltip + L"\n" + _("Soft shadows: %s",
-        UserConfigParams::m_pcss ? enabled : disabled);
 
     //I18N: in graphical options
     tooltip = tooltip + L"\n" + _("Animated Characters: %s",
@@ -609,7 +605,6 @@ void OptionsScreenVideo::eventCallback(Widget* widget, const std::string& name,
         UserConfigParams::m_geometry_level     = (m_presets[level].geometry_detail == 0 ? 2 :
                                                   m_presets[level].geometry_detail == 2 ? 0 :
                                                   m_presets[level].geometry_detail);
-        UserConfigParams::m_pcss               = m_presets[level].pcss;
 
         updateGfxSlider();
     }

src/states_screens/options/options_screen_video.hpp

@@ -40,7 +40,6 @@ struct GFXPreset
     int image_quality;
     bool degraded_ibl;
     int geometry_detail;
-    bool pcss;
 };
 
 struct BlurPreset