quakeforge/libs/video/renderer/glsl/quakeski.frag

31 lines
620 B
GLSL

uniform sampler2D palette;
uniform sampler2D solid;
uniform sampler2D trans;
uniform float realtime;
varying vec3 direction;
const float SCALE = 189.0 / 64.0;
void
main (void)
{
float len;
float pix;
vec2 flow = vec2 (1.0, 1.0);
vec2 st;
vec3 dir = direction;
dir.z *= 3.0;
len = dot (dir, dir);
len = SCALE * inversesqrt (len);
st = direction.xy * len + flow * realtime / 8.0;
pix = texture2D (trans, st).r;
if (pix == 0.0) {
st = direction.xy * len + flow * realtime / 16.0;
pix = texture2D (solid, st).r;
}
gl_FragColor = texture2D (palette, vec2 (pix, 0.0));
}