21 lines
658 B
GLSL
21 lines
658 B
GLSL
/// tip:"Ensure colorbuffer is alpha clear before calling this one."
|
|
|
|
uniform int thickness; /// set:2
|
|
uniform vec4 border_color; /// set:1,1,0,1
|
|
|
|
void main() {
|
|
vec4 texel = texture(iChannel0, uv);
|
|
float outline = 0.0;
|
|
if( texel.a == 0.0 ) {
|
|
for( int x = -thickness; x <= thickness; x++ ) {
|
|
for( int y = -thickness;y <= thickness; y++ ) {
|
|
float sample = texture(iChannel0, uv+vec2(float(x)/iWidth, float(y)/iHeight)).a;
|
|
if( sample > 0.0 ) {
|
|
outline = 1.0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
FRAGCOLOR = mix(texel, border_color, outline * border_color.a);
|
|
} |