Pixel-Composer/shaders/sh_d3d_outline/sh_d3d_outline.fsh
2023-08-14 19:22:04 +02:00

40 lines
772 B
GLSL

//
// Simple passthrough fragment shader
//
varying vec2 v_vTexcoord;
varying vec4 v_vColour;
uniform vec2 dimension;
uniform vec4 outlineColor;
#define TAU 6.283185307179586
void main() {
vec2 pixelPosition = v_vTexcoord * dimension;
gl_FragColor = vec4(0.);
vec4 sam = texture2D( gm_BaseTexture, v_vTexcoord );
if(sam.r > 0.5) return;
for(float i = 1.; i <= 2.; i++) {
float base = 1.;
float top = 0.;
for(float j = 0.; j <= 8.; j++) {
float ang = top / base * TAU;
top += 2.;
if(top >= base) {
top = 1.;
base *= 2.;
}
vec2 pxs = (pixelPosition + vec2( cos(ang), sin(ang)) * i) / dimension;
vec4 sam = texture2D( gm_BaseTexture, pxs );
if(sam.r > 0.5) {
gl_FragColor = outlineColor;
return;
}
}
}
}