stk-code_catmod/data/shaders/godray.frag
vincentlj fa068d7810 OGL32CTX: Ask #version 130 for all our shaders
git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@14919 178a84e3-b1eb-0310-8ba1-8eac791a3b58
2014-01-05 00:08:00 +00:00

31 lines
527 B
GLSL

#version 130
uniform sampler2D tex;
uniform vec2 sunpos;
#define SAMPLES 12
const float decaystep = 0.88;
void main()
{
vec2 texc = gl_TexCoord[0].xy;
vec2 tosun = sunpos - texc;
if (dot(tosun, tosun) > 0.49) discard;
vec2 dist = tosun * 1.0/(float(SAMPLES) * 1.12);
vec3 col = texture2D(tex, texc).xyz;
float decay = 1.0;
for (int i = 0; i < SAMPLES; i++) {
texc += dist;
vec3 here = texture2D(tex, texc).xyz;
here *= decay;
col += here;
decay *= decaystep;
}
gl_FragColor = vec4(col, 1.0) * 0.8;
}