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fteqw/engine/shaders/glsl/crepuscular_rays.glsl
Spoike 33a540806e Small tweeks, bugfixes, breakages, cleanups...
Added $reflection texture map for (water) shaders. Just renders the screen to an fbo before rendering the surface.
hub/savegame fixes.


git-svn-id: https://svn.code.sf.net/p/fteqw/code/trunk@4034 fc73d0e0-1445-4013-8a0c-d673dee63da5
2012-05-09 15:30:53 +00:00

43 lines
1.3 KiB
GLSL

!!cvarf crep_decay
!!cvarf crep_density
!!cvarf crep_weight
//this is a post-processing shader, drawn in 2d
//there will be a render target containing sky surfaces drawn with crepuscular_sky, and everything else drawn with crepuscular_opaque (to mask out the sky)
//this shader then just smudges the sky out a bit as though its coming from the sun or whatever through the clouds.
//yoinked from http://fabiensanglard.net/lightScattering/index.php
varying vec2 tc;
#ifdef VERTEX_SHADER
attribute vec2 v_texcoord;
void main ()
{
tc = v_texcoord;
gl_Position = v_position;
}
#endif
#ifdef FRAGMENT_SHADER
const float crep_decay = 0.94;
const float crep_density = 0.5;
const float crep_weight = 0.2;
uniform vec3 l_lightcolour;
uniform vec3 l_lightscreen;
uniform sampler2D s_t0;
const int NUM_SAMPLES = 100;
void main()
{
vec2 deltaTextCoord = vec2(tc.st - l_lightscreen.xy);
vec2 textCoo = tc.st;
deltaTextCoord *= 1.0 / float(NUM_SAMPLES) * crep_density;
float illuminationDecay = 1.0;
for(int i=0; i < NUM_SAMPLES ; i++)
{
textCoo -= deltaTextCoord;
vec4 sample = texture2D(s_t0, textCoo);
sample *= illuminationDecay * crep_weight;
gl_FragColor += sample;
illuminationDecay *= crep_decay;
}
gl_FragColor *= vec4(l_lightcolour, 1.0);
}
#endif