SuperTuxKart 1.5 upstream source (from official release tarball)

data/shaders/sp_tilling_mitigation.frag

@@ -0,0 +1,57 @@
+in vec3 bitangent;
+in vec4 color;
+in float hue_change;
+in vec3 normal;
+in vec3 tangent;
+in vec2 uv;
+in float camdist;
+
+layout(location = 0) out vec4 o_diffuse_color;
+layout(location = 1) out vec4 o_normal_color;
+
+#stk_include "utils/encode_normal.frag"
+#stk_include "utils/rgb_conversion.frag"
+#stk_include "utils/sp_texture_sampling.frag"
+
+void main()
+{
+    vec4 col = multi_sampleTextureLayer0(uv, camdist);
+
+    if (hue_change > 0.0)
+    {
+        float mask = col.a;
+        vec3 old_hsv = rgbToHsv(col.rgb);
+        float mask_step = step(mask, 0.5);
+#if !defined(Advanced_Lighting_Enabled)
+        // For similar color
+        float saturation = mask * 1.825; // 2.5 * 0.5 ^ (1. / 2.2)
+#else
+        float saturation = mask * 2.5;
+#endif
+        vec2 new_xy = mix(vec2(old_hsv.x, old_hsv.y), vec2(hue_change,
+            max(old_hsv.y, saturation)), vec2(mask_step, mask_step));
+        vec3 new_color = hsvToRgb(vec3(new_xy.x, new_xy.y, old_hsv.z));
+        col = vec4(new_color.r, new_color.g, new_color.b, 1.0);
+    }
+
+    vec3 final_color = col.xyz * color.xyz;
+
+#if defined(Advanced_Lighting_Enabled)
+    vec4 layer_2 = multi_sampleTextureLayer2(uv, camdist);
+    vec4 layer_3 = multi_sampleTextureLayer3(uv, camdist);
+    o_diffuse_color = vec4(final_color, layer_2.z);
+
+    vec3 tangent_space_normal = 2.0 * layer_3.xyz - 1.0;
+    vec3 frag_tangent = normalize(tangent);
+    vec3 frag_bitangent = normalize(bitangent);
+    vec3 frag_normal = normalize(normal);
+    mat3 t_b_n = mat3(frag_tangent, frag_bitangent, frag_normal);
+
+    vec3 world_normal = t_b_n * tangent_space_normal;
+
+    o_normal_color.xy = EncodeNormal(normalize(world_normal));
+    o_normal_color.zw = layer_2.xy;
+#else
+    o_diffuse_color = vec4(final_color, 1.0);
+#endif
+}