kwin/effects/data/liquid.frag
Rivo Laks e979de43fb Another demo effect which uses shader and render target to turn your screen into a liquid, wavy surface.
Soon we'll have more silly effects than Beryl/Compiz ;-)

svn path=/branches/work/kwin_composite/; revision=655575
2007-04-18 19:44:49 +00:00

50 lines
1.4 KiB
GLSL

uniform sampler2D sceneTex;
uniform float displayWidth;
uniform float displayHeight;
uniform float time;
varying vec2 pos;
#define DEG2RAD (6.2832/360.0)
// Converts pixel coordinates to texture coordinates
vec2 pix2tex(vec2 pix)
{
return vec2(pix.x / displayWidth, 1.0 - pix.y / displayHeight);
}
float wave(vec2 pos, vec2 wave_dir, float wave_length, float wave_speed)
{
return sin(((pos.x * wave_dir.x) + (pos.y * wave_dir.y)) * 6.2832 / wave_length +
time * wave_speed * 6.2832 / wave_length);
}
vec2 displacement(float wave_angle, float wave_length, float wave_speed, float wave_height)
{
vec2 wave_dir = vec2(cos(wave_angle * DEG2RAD), sin(wave_angle * DEG2RAD));
return wave_dir * (wave(pos, wave_dir, wave_length, wave_speed) * wave_height);
}
// Only for debugging
float wave_color(float wave_angle, float wave_length, float wave_speed, float wave_height)
{
vec2 wave_dir = vec2(cos(wave_angle * DEG2RAD), sin(wave_angle * DEG2RAD));
return wave(pos, wave_dir, wave_length, wave_speed) * 0.5 + 0.5;
}
void main()
{
vec2 texpos = pos;
texpos += displacement( 20.0, 250.0, 120.0, 4.0);
texpos += displacement(-40.0, 350.0, 100.0, 4.0);
texpos += displacement(240.0, 1000.0, 100.0, 12.0);
texpos += displacement(160.0, 50.0, 30.0, 2.0);
vec3 tex = texture2D(sceneTex, pix2tex(texpos)).rgb;
//tex.r = wave_color( 20, 250, 150, 4); // debug
gl_FragColor = vec4(tex, 1.0);
}