54 lines
1.4 KiB
GLSL
54 lines
1.4 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;
|
|
uniform int iteration;
|
|
|
|
varying vec2 vTexCoord;
|
|
|
|
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) {
|
|
float rad = ceil(sigma);
|
|
|
|
float sum = 0.0;
|
|
|
|
vec4 color = vec4(0.0);
|
|
|
|
bool radius_is_zero = (rad == 0.0);
|
|
|
|
if (!radius_is_zero) {
|
|
for (float x=-rad+0.5;x<=rad;x+=2.0) {
|
|
sum += gaussian2(x, 0.0, sigma);
|
|
}
|
|
}
|
|
|
|
if (iteration == 0 && horiz_blur && !radius_is_zero) {
|
|
for (float x=-rad+0.5;x<=rad;x+=2.0) {
|
|
float weight = (gaussian2(x, 0.0, sigma)/sum);
|
|
color += texture2D(image, (vec2(gl_FragCoord.x+x, gl_FragCoord.y))/resolution)*(weight);
|
|
}
|
|
gl_FragColor = color;
|
|
} else if (iteration == 1 && vert_blur && !radius_is_zero) {
|
|
for (float x=-rad+0.5;x<=rad;x+=2.0) {
|
|
float weight = (gaussian2(0.0, x, sigma)/sum);
|
|
color += texture2D(image, (vec2(gl_FragCoord.x, gl_FragCoord.y+x))/resolution)*(weight);
|
|
}
|
|
gl_FragColor = color;
|
|
} else {
|
|
gl_FragColor = texture2D(image, vTexCoord);
|
|
}
|
|
} |