light_world.lua/shader/glow.glsl
2014-03-19 23:22:46 +01:00

20 lines
574 B
GLSL

extern Image glowImage;
extern float glowTime;
vec4 effect(vec4 color, Image texture, vec2 texture_coords, vec2 pixel_coords) {
vec3 glowInfo = Texel(glowImage, texture_coords).rgb;
if(glowInfo.r != glowInfo.g) {
float glowStrength = glowTime + glowInfo.b;
if(mod(glowStrength, 2.0) < 1.0) {
glowInfo.b = mod(glowStrength, 1.0);
} else {
glowInfo.b = 1.0 - mod(glowStrength, 1.0);
}
return Texel(texture, texture_coords) * (glowInfo.g + glowInfo.b * (glowInfo.r - glowInfo.g));
}
return vec4(Texel(texture, texture_coords).rgb * glowInfo.r, 1.0);
}