tibia-client/modules/game_shaders/shaders/radialblur.frag

50 lines
1.8 KiB
GLSL
Raw Normal View History

2012-06-14 20:26:55 +02:00
uniform sampler2D u_Tex0;
varying vec2 v_TexCoord;
// some const, tweak for best look
const float sampleDist = 1.0;
const float sampleStrength = 2.2;
void main(void)
{
// 0.5,0.5 is the center of the screen
// so substracting v_TexCoord from it will result in
// a vector pointing to the middle of the screen
vec2 dir = 0.5 - v_TexCoord;
// calculate the distance to the center of the screen
float dist = sqrt(dir.x*dir.x + dir.y*dir.y);
// normalize the direction (reuse the distance)
dir = dir/dist;
// this is the original colour of this fragment
// using only this would result in a nonblurred version
vec4 color = texture2D(u_Tex0,v_TexCoord);
vec4 sum = color;
// take 10 additional blur samples in the direction towards
// the center of the screen
2012-06-19 01:58:56 +02:00
sum += texture2D(u_Tex0, v_TexCoord - 0.08 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord - 0.05 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord - 0.03 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord - 0.02 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord - 0.01 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord + 0.01 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord + 0.02 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord + 0.03 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord + 0.05 * dir * sampleDist);
sum += texture2D(u_Tex0, v_TexCoord + 0.08 * dir * sampleDist);
2012-06-14 20:26:55 +02:00
// we have taken eleven samples
sum *= 1.0/11.0;
// weighten the blur effect with the distance to the
// center of the screen ( further out is blurred more)
float t = dist * sampleStrength;
t = clamp(t ,0.0,1.0); //0 <= t <= 1
//Blend the original color with the averaged pixels
gl_FragColor = mix(color, sum, t);
2012-06-19 01:58:56 +02:00
}