shaders: add skia shaders

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

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

1 files changed, 106 insertions, 0 deletions

diff --git a/shaders/skia/550-4.shader_test b/shaders/skia/550-4.shader_test
new file mode 100644
index 0000000..2b6e6cb
--- /dev/null
+++ b/shaders/skia/550-4.shader_test
@@ -0,0 +1,106 @@
+[require]
+GLSL >= 1.40
+
+[fragment shader]
+#version 140
+
+out vec4 sk_FragColor;
+uniform vec2 ubaseFrequency_Stage2_c0_c0;
+uniform float uz_Stage2_c0_c0;
+uniform sampler2D uTextureSampler_0_Stage1;
+uniform sampler2D uTextureSampler_0_Stage2;
+uniform sampler2D uTextureSampler_1_Stage2;
+noperspective in vec2 vTransformedCoords_0_Stage0;
+noperspective in vec2 vTransformedCoords_1_Stage0;
+vec3 fade_Stage2_c0_c0(vec3 t) {
+    return ((t * t) * t) * (t * (t * 6.0 - 15.0) + 10.0);
+}
+float perm_Stage2_c0_c0(float x) {
+    return texture(uTextureSampler_0_Stage2, vec2(fract(x / 256.0), 0.0)).x * 255.0;
+}
+float grad_Stage2_c0_c0(float x, vec3 p) {
+    return dot(texture(uTextureSampler_1_Stage2, vec2(fract(x / 16.0), 0.0)).xyz * 255.0 - vec3(1.0), p);
+}
+float lerp_Stage2_c0_c0(float a, float b, float w) {
+    return a + w * (b - a);
+}
+float noise_Stage2_c0_c0(vec3 p) {
+    vec3 P = mod(floor(p), 256.0);
+    p -= floor(p);
+    vec3 f = fade_Stage2_c0_c0(p);
+    float A = perm_Stage2_c0_c0(P.x) + P.y;
+    float AA = perm_Stage2_c0_c0(A) + P.z;
+    float AB = perm_Stage2_c0_c0(A + 1.0) + P.z;
+    float B = perm_Stage2_c0_c0(P.x + 1.0) + P.y;
+    float BA = perm_Stage2_c0_c0(B) + P.z;
+    float BB = perm_Stage2_c0_c0(B + 1.0) + P.z;
+    float result = lerp_Stage2_c0_c0(lerp_Stage2_c0_c0(lerp_Stage2_c0_c0(grad_Stage2_c0_c0(perm_Stage2_c0_c0(AA), p), grad_Stage2_c0_c0(perm_Stage2_c0_c0(BA), p + vec3(-1.0, 0.0, 0.0)), f.x), lerp_Stage2_c0_c0(grad_Stage2_c0_c0(perm_Stage2_c0_c0(AB), p + vec3(0.0, -1.0, 0.0)), grad_Stage2_c0_c0(perm_Stage2_c0_c0(BB), p + vec3(-1.0, -1.0, 0.0)), f.x), f.y), lerp_Stage2_c0_c0(lerp_Stage2_c0_c0(grad_Stage2_c0_c0(perm_Stage2_c0_c0(AA + 1.0), p + vec3(0.0, 0.0, -1.0)), grad_Stage2_c0_c0(perm_Stage2_c0_c0(BA + 1.0), p + vec3(-1.0, 0.0, -1.0)), f.x), lerp_Stage2_c0_c0(grad_Stage2_c0_c0(perm_Stage2_c0_c0(AB + 1.0), p + vec3(0.0, -1.0, -1.0)), grad_Stage2_c0_c0(perm_Stage2_c0_c0(BB + 1.0), p + vec3(-1.0, -1.0, -1.0)), f.x), f.y), f.z);
+    return result;
+}
+float noiseOctaves_Stage2_c0_c0(vec3 p) {
+    float result = 0.0;
+    float ratio = 1.0;
+    for (float i = 0.0;i < 2.0; i++) {
+        result += noise_Stage2_c0_c0(p) / ratio;
+        p *= 2.0;
+        ratio *= 2.0;
+    }
+    return (result + 1.0) / 2.0;
+}
+vec4 ImprovedPerlinNoise_Stage2_c0_c0(vec4 _input) {
+    vec4 _output;
+    vec2 coords = vTransformedCoords_1_Stage0 * ubaseFrequency_Stage2_c0_c0;
+    float r = noiseOctaves_Stage2_c0_c0(vec3(coords, uz_Stage2_c0_c0));
+    float g = noiseOctaves_Stage2_c0_c0(vec3(coords, uz_Stage2_c0_c0));
+    float b = noiseOctaves_Stage2_c0_c0(vec3(coords, uz_Stage2_c0_c0));
+    float a = noiseOctaves_Stage2_c0_c0(vec3(coords, uz_Stage2_c0_c0));
+    _output = vec4(r, g, b, a);
+    _output = clamp(_output, 0.0, 1.0);
+    _output = vec4(_output.xyz * _output.www, _output.w);
+    return _output;
+}
+float _blend_overlay_component(float sc, float sa, float dc, float da) {
+    if (2.0 * dc <= da) {
+        return (2.0 * sc) * dc;
+    }
+    return sa * da - (2.0 * (da - dc)) * (sa - sc);
+}
+vec4 blend_overlay(vec4 src, vec4 dst) {
+    vec4 result = vec4(_blend_overlay_component(src.x, src.w, dst.x, dst.w), _blend_overlay_component(src.y, src.w, dst.y, dst.w), _blend_overlay_component(src.z, src.w, dst.z, dst.w), src.w + (1.0 - src.w) * dst.w);
+    result.xyz += dst.xyz * (1.0 - src.w) + src.xyz * (1.0 - dst.w);
+    return result;
+}
+vec4 blend_hard_light(vec4 src, vec4 dst) {
+    return blend_overlay(dst, src);
+}
+void main() {
+    vec4 output_Stage1;
+    {
+        output_Stage1 = texture(uTextureSampler_0_Stage1, vTransformedCoords_0_Stage0);
+    }
+    vec4 output_Stage2;
+    {
+        output_Stage2 = blend_hard_light(ImprovedPerlinNoise_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);
+}
+