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dotfiles/gnome/.local/share/gnome-shell/extensions/blur-my-shell@aunetx/effects/blur_effect.glsl

114 lines
3.5 KiB
GLSL

uniform sampler2D tex;
uniform float sigma;
uniform int dir;
uniform float brightness;
uniform float corner_radius;
uniform float width;
uniform float height;
float circleBounds(vec2 p, vec2 center, float clip_radius) {
vec2 delta = p - center;
float dist_squared = dot(delta, delta);
float outer_radius = clip_radius + 0.5;
if (dist_squared >= (outer_radius * outer_radius))
return 0.0;
float inner_radius = clip_radius - 0.5;
if (dist_squared <= (inner_radius * inner_radius))
return 1.0;
return outer_radius - sqrt(dist_squared);
}
vec4 shapeCorner(vec4 pixel, vec2 p, vec2 center, float clip_radius) {
float alpha = circleBounds(p, center, clip_radius);
return vec4(pixel.rgb * alpha, min(alpha, pixel.a));
}
vec4 getTexture(vec2 uv) {
if (uv.x < 2. / width)
uv.x = 2. / width;
if (uv.y < 2. / height)
uv.y = 2. / height;
if (uv.x > 1. - 3. / width)
uv.x = 1. - 3. / width;
if (uv.y > 1. - 3. / height)
uv.y = 1. - 3. / height;
return texture2D(tex, uv);
}
void main(void) {
vec2 uv = cogl_tex_coord_in[0].xy;
vec2 pos = uv * vec2(width, height);
vec2 direction = vec2(dir, (1.0 - dir));
float pixel_step;
if (dir == 0)
pixel_step = 1.0 / height;
else
pixel_step = 1.0 / width;
vec3 gauss_coefficient;
gauss_coefficient.x = 1.0 / (sqrt(2.0 * 3.14159265) * sigma);
gauss_coefficient.y = exp(-0.5 / (sigma * sigma));
gauss_coefficient.z = gauss_coefficient.y * gauss_coefficient.y;
float gauss_coefficient_total = gauss_coefficient.x;
vec4 ret = getTexture(uv) * gauss_coefficient.x;
gauss_coefficient.xy *= gauss_coefficient.yz;
int n_steps = int(ceil(1.5 * sigma)) * 2;
for (int i = 1; i <= n_steps; i += 2) {
float coefficient_subtotal = gauss_coefficient.x;
gauss_coefficient.xy *= gauss_coefficient.yz;
coefficient_subtotal += gauss_coefficient.x;
float gauss_ratio = gauss_coefficient.x / coefficient_subtotal;
float foffset = float(i) + gauss_ratio;
vec2 offset = direction * foffset * pixel_step;
ret += getTexture(uv + offset) * coefficient_subtotal;
ret += getTexture(uv - offset) * coefficient_subtotal;
gauss_coefficient_total += 2.0 * coefficient_subtotal;
gauss_coefficient.xy *= gauss_coefficient.yz;
}
vec4 outColor = ret / gauss_coefficient_total;
// apply brightness and rounding on the second pass (dir==0 comes last)
if (dir == 0) {
// left side
if (pos.x < corner_radius) {
// top left corner
if (pos.y < corner_radius) {
outColor = shapeCorner(outColor, pos, vec2(corner_radius + 2., corner_radius + 2.), corner_radius);
// bottom left corner
} else if (pos.y > height - corner_radius) {
outColor = shapeCorner(outColor, pos, vec2(corner_radius + 2., height - corner_radius - 1.), corner_radius);
}
// right side
} else if (pos.x > width - corner_radius) {
// top right corner
if (pos.y < corner_radius) {
outColor = shapeCorner(outColor, pos, vec2(width - corner_radius - 1., corner_radius + 2.), corner_radius);
// bottom right corner
} else if (pos.y > height - corner_radius) {
outColor = shapeCorner(outColor, pos, vec2(width - corner_radius - 1., height - corner_radius - 1.), corner_radius);
}
}
outColor.rgb *= brightness;
}
cogl_color_out = outColor;
}