Files
oak-editor/effects/gaussianblur.frag
T

77 lines
2.8 KiB
GLSL

#version 110
#define M_PI 3.1415926535897932384626433832795
uniform sampler2D image;
uniform float radius;
uniform float sigma;
uniform vec2 resolution;
uniform bool horiz_blur;
uniform bool vert_blur;
float gaussian(float x, float sigma) {
return (1.0/(sigma*sqrt(2.0*M_PI)))*exp(-0.5*pow(x/sigma, 2.0));
}
float gaussian2(float x, float y, float sigma) {
return (1.0/(pow(sigma, 2.0)*2.0*M_PI))*exp(-0.5*((pow(x, 2.0) + pow(y, 2.0))/pow(sigma, 2.0)));
}
void main(void) {
if (radius == 0.0 || sigma == 0.0 || (!horiz_blur && !vert_blur)) {
gl_FragColor = texture2D(image, gl_FragCoord.xy/resolution);
} else {
float middleWeight = gaussian(0.0, sigma);
float sum = middleWeight;
if (horiz_blur && vert_blur) {
for (float i=1.0;i<=radius;i++) {
sum += (4.0*gaussian2(i, 0.0, sigma));
}
for (float x=1.0;x<=radius;x++) {
for (float y=1.0;y<=radius;y++) {
sum += (4.0*gaussian2(x, y, sigma));
}
}
gl_FragColor = texture2D(image, gl_FragCoord.xy/resolution)*(middleWeight/sum);
for (float i=1.0;i<=radius;i++) {
float weight = (gaussian2(i, 0.0, sigma)/sum);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x-i, gl_FragCoord.y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x+i, gl_FragCoord.y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x, gl_FragCoord.y+i))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x, gl_FragCoord.y-i))/resolution)*(weight);
}
for (float x=1.0;x<=radius;x++) {
for (float y=1.0;y<=radius;y++) {
float weight = (gaussian2(x, y, sigma)/sum);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x-x, gl_FragCoord.y-y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x+x, gl_FragCoord.y+y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x-x, gl_FragCoord.y+y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x+x, gl_FragCoord.y-y))/resolution)*(weight);
}
}
} else {
for (float i=1.0;i<=radius;i++) {
sum += (2.0*gaussian(i, sigma));
}
gl_FragColor = texture2D(image, gl_FragCoord.xy/resolution)*(middleWeight/sum);
for (float i=1.0;i<=radius;i++) {
float weight = gaussian(i, sigma)/sum;
if (horiz_blur) {
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x-i, gl_FragCoord.y))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x+i, gl_FragCoord.y))/resolution)*(weight);
} else {
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x, gl_FragCoord.y-i))/resolution)*(weight);
gl_FragColor += texture2D(image, (vec2(gl_FragCoord.x, gl_FragCoord.y+i))/resolution)*(weight);
}
}
}
}
}