shaders: add skia shaders

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

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

1 files changed, 64 insertions, 0 deletions

diff --git a/shaders/skia/253-5.shader_test b/shaders/skia/253-5.shader_test
new file mode 100644
index 0000000..4c5810a
--- /dev/null
+++ b/shaders/skia/253-5.shader_test
@@ -0,0 +1,64 @@
+[require]
+GLSL >= 1.40
+
+[fragment shader]
+#version 140
+
+#extension GL_ARB_fragment_coord_conventions : require
+layout(origin_upper_left) in vec4 gl_FragCoord;
+out vec4 sk_FragColor;
+uniform vec4 ucircle_Stage2_c0_c0;
+uniform sampler2D uTextureSampler_0_Stage1;
+noperspective in vec2 vTransformedCoords_0_Stage0;
+vec4 CircleEffect_Stage2_c0_c0(vec4 _input) {
+    vec4 _output;
+    float d;
+    {
+        d = (length((ucircle_Stage2_c0_c0.xy - gl_FragCoord.xy) * ucircle_Stage2_c0_c0.w) - 1.0) * ucircle_Stage2_c0_c0.z;
+    }
+    {
+        _output = d > 0.5 ? _input : vec4(0.0);
+    }
+    return _output;
+}
+vec4 ClampFragmentProcessor_Stage2_c1_c0(vec4 _input) {
+    vec4 _output;
+    {
+        float alpha = clamp(_input.w, 0.0, 1.0);
+        _output = vec4(clamp(_input.xyz, 0.0, alpha), alpha);
+    }
+    return _output;
+}
+vec4 blend_dst_over(vec4 src, vec4 dst) {
+    return (1.0 - dst.w) * src + dst;
+}
+void main() {
+    vec4 output_Stage1;
+    {
+        output_Stage1 = texture(uTextureSampler_0_Stage1, vTransformedCoords_0_Stage0);
+    }
+    vec4 output_Stage2;
+    {
+        vec4 inputColor = vec4(output_Stage1.xyz, 1.0);
+        output_Stage2 = blend_dst_over(CircleEffect_Stage2_c0_c0(inputColor), ClampFragmentProcessor_Stage2_c1_c0(inputColor));
+        output_Stage2 *= output_Stage1.w;
+    }
+    {
+        sk_FragColor = output_Stage2;
+    }
+}
+
+[vertex shader]
+#version 140
+
+uniform vec4 sk_RTAdjust;
+uniform mat3 uCoordTransformMatrix_0_Stage0;
+in vec2 position;
+in vec2 localCoord;
+noperspective out vec2 vTransformedCoords_0_Stage0;
+void main() {
+    vTransformedCoords_0_Stage0 = (uCoordTransformMatrix_0_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);
+}
+