stk-code_catmod/data/shaders/displace.frag
2013-11-30 21:33:06 +00:00

41 lines
981 B
GLSL

uniform sampler2D tex;
uniform vec2 screen;
uniform vec2 dir;
uniform vec2 dir2;
varying float camdist;
void main()
{
vec2 tc = gl_TexCoord[0].xy;
vec4 col = vec4(0.0);
const float maxlen = 0.02;
float horiz = texture2D(tex, tc + dir).x;
float vert = texture2D(tex, (tc.yx + dir2) * vec2(0.9)).x;
vec2 offset = vec2(horiz, vert);
offset *= 2.0;
offset -= 1.0;
// Fade according to distance to cam
float fade = 1.0 - smoothstep(1.0, 40.0, camdist);
// Fade according to distance from the edges
vec2 edger = gl_TexCoord[1].xy;
const float mindist = 0.1;
fade *= smoothstep(0.0, mindist, edger.x) * smoothstep(0.0, mindist, edger.y) *
(1.0 - smoothstep(1.0 - mindist, 1.0, edger.x)) *
(1.0 - smoothstep(1.0 - mindist, 1.0, edger.y));
offset *= 50.0 * fade * maxlen;
col.r = step(offset.x, 0.0) * -offset.x;
col.g = step(0.0, offset.x) * offset.x;
col.b = step(offset.y, 0.0) * -offset.y;
col.a = step(0.0, offset.y) * offset.y;
gl_FragColor = col;
}