shaders: add skia shaders

Add shaders extracted from skia's unit tests[1]

[1] https://skia.org/dev/testing/testing

1 files changed, 77 insertions, 0 deletions

diff --git a/shaders/skia/616-4.shader_test b/shaders/skia/616-4.shader_test
new file mode 100644
index 0000000..a51e699
--- /dev/null
+++ b/shaders/skia/616-4.shader_test
@@ -0,0 +1,77 @@
+[require]
+GLSL >= 1.40
+
+[fragment shader]
+#version 140
+
+out vec4 sk_FragColor;
+uniform float uinnerThreshold_Stage2_c0_c0;
+uniform float uouterThreshold_Stage2_c0_c0;
+uniform sampler2D uTextureSampler_0_Stage1;
+uniform sampler2D uTextureSampler_0_Stage2;
+noperspective in vec2 vTransformedCoords_0_Stage0;
+noperspective in vec2 vTransformedCoords_1_Stage0;
+vec4 AlphaThresholdFragmentProcessor_Stage2_c0_c0(vec4 _input) {
+    vec4 _output;
+    vec4 color = _input;
+    vec4 mask_color = texture(uTextureSampler_0_Stage2, vTransformedCoords_1_Stage0);
+    if (mask_color.w < 0.5) {
+        if (color.w > uouterThreshold_Stage2_c0_c0) {
+            float scale = uouterThreshold_Stage2_c0_c0 / color.w;
+            color.xyz *= scale;
+            color.w = uouterThreshold_Stage2_c0_c0;
+        }
+    } else if (color.w < uinnerThreshold_Stage2_c0_c0) {
+        float scale = uinnerThreshold_Stage2_c0_c0 / max(0.0010000000474974513, color.w);
+        color.xyz *= scale;
+        color.w = uinnerThreshold_Stage2_c0_c0;
+    }
+    _output = color;
+    return _output;
+}
+float _guarded_divide(float n, float d) {
+    return n / d;
+}
+float _color_burn_component(float sc, float sa, float dc, float da) {
+    if (da == dc) {
+        return (sa * da + sc * (1.0 - da)) + dc * (1.0 - sa);
+    } else if (sc == 0.0) {
+        return dc * (1.0 - sa);
+    }
+    float d = max(0.0, da - _guarded_divide((da - dc) * sa, sc));
+    return (d * sa + sc * (1.0 - da)) + dc * (1.0 - sa);
+}
+vec4 blend_color_burn(vec4 src, vec4 dst) {
+    return vec4(_color_burn_component(src.x, src.w, dst.x, dst.w), _color_burn_component(src.y, src.w, dst.y, dst.w), _color_burn_component(src.z, src.w, dst.z, dst.w), src.w + (1.0 - src.w) * dst.w);
+}
+void main() {
+    vec4 output_Stage1;
+    {
+        output_Stage1 = texture(uTextureSampler_0_Stage1, vTransformedCoords_0_Stage0);
+    }
+    vec4 output_Stage2;
+    {
+        output_Stage2 = blend_color_burn(AlphaThresholdFragmentProcessor_Stage2_c0_c0(vec4(1.0)), output_Stage1);
+    }
+    {
+        sk_FragColor = output_Stage2;
+    }
+}
+
+[vertex shader]
+#version 140
+
+uniform vec4 sk_RTAdjust;
+uniform mat3 uCoordTransformMatrix_0_Stage0;
+uniform mat3 uCoordTransformMatrix_1_Stage0;
+in vec2 position;
+in vec2 localCoord;
+noperspective out vec2 vTransformedCoords_0_Stage0;
+noperspective out vec2 vTransformedCoords_1_Stage0;
+void main() {
+    vTransformedCoords_0_Stage0 = (uCoordTransformMatrix_0_Stage0 * vec3(localCoord, 1.0)).xy;
+    vTransformedCoords_1_Stage0 = (uCoordTransformMatrix_1_Stage0 * vec3(localCoord, 1.0)).xy;
+    gl_Position = vec4(position.x, position.y, 0.0, 1.0);
+    gl_Position = vec4(gl_Position.xy * sk_RTAdjust.xz + gl_Position.ww * sk_RTAdjust.yw, 0.0, gl_Position.w);
+}
+