#version 100 | |
precision mediump float; | |
uniform sampler2D uSampler0_Stage0; | |
uniform vec4 urect_Stage1; | |
uniform float uRTHeight; | |
varying vec4 vColor; | |
varying vec2 vMatrixCoord_Stage0; | |
// This texture is used when Skia renders a box shadow that has a very large | |
// blur applied to it, relative to box size. It will do so by first rendering | |
// to a texture and then using that texture to blur, masked by the outside | |
// of a rectangle. | |
void main() { | |
vec4 fragCoordYDown = vec4(gl_FragCoord.x, uRTHeight - gl_FragCoord.y, 1.0, 1.0); | |
vec4 output_Stage0; | |
{ | |
// Stage 0: Texture | |
output_Stage0 = (vColor * texture2D(uSampler0_Stage0, vMatrixCoord_Stage0)); | |
} | |
vec4 output_Stage1; | |
{ | |
// Stage 1: AARect | |
float xSub, ySub; | |
xSub = min(fragCoordYDown.x - urect_Stage1.x, 0.0); | |
xSub += min(urect_Stage1.z - fragCoordYDown.x, 0.0); | |
ySub = min(fragCoordYDown.y - urect_Stage1.y, 0.0); | |
ySub += min(urect_Stage1.w - fragCoordYDown.y, 0.0); | |
float alpha = (1.0 + max(xSub, -1.0)) * (1.0 + max(ySub, -1.0)); | |
alpha = 1.0 - alpha; | |
output_Stage1 = (output_Stage0 * alpha); | |
} | |
gl_FragColor = output_Stage1; | |
} | |