shaderlib: Implement gaussian_blur(); implements #39

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ChaoticByte 2025-01-11 15:59:58 +01:00
parent 85d33d5d77
commit d08329c750
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3 changed files with 42 additions and 2 deletions

8
examples/blur.gdshader Normal file
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@ -0,0 +1,8 @@
shader_type canvas_item;
//!load ./images/swamp.jpg
#include "res://shaderlib/blur.gdshaderinc"
void fragment() {
COLOR = gaussian_blur(TEXTURE, UV, 48, 24.0);
}

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@ -0,0 +1,30 @@
// gaussian_blur adapted from https://godotshaders.com/shader/customizable-gausian-blur/
// original code by https://godotshaders.com/author/djbob-gaming-yt/
// maximum radius is 64
vec4 gaussian_blur(sampler2D texture, vec2 uv, int radius, float sigma) {
vec2 resolution = 1.0 / vec2(textureSize(texture, 0));
// calculate kernel
float kernel[64];
float sum = 0.0;
for (int i = 0; i <= radius; i++) {
kernel[i] = exp(-0.5 * float(i * i) / (sigma * sigma));
sum += i == 0 ? kernel[i] : 2.0 * kernel[i];
}
for (int i = 0; i <= radius; i++) {
kernel[i] /= sum;
}
//
vec4 final_color = vec4(0.0);
float total_weight = 0.0;
for (int x = -radius; x <= radius; x++) {
for (int y = -radius; y <= radius; y++) {
float weight = kernel[abs(x)] * kernel[abs(y)];
vec2 offset = vec2(float(x), float(y)) * resolution;
final_color += texture(texture, uv + offset) * weight;
total_weight += weight;
}
}
final_color /= total_weight;
return final_color;
}

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@ -133,14 +133,16 @@ var shaderlib_regex = {
"transform": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/transform\.gdshaderinc\"'),
"transparency": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/transparency\.gdshaderinc\"'),
"effects": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/effects\.gdshaderinc\"'),
"denoise": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/denoise\.gdshaderinc\"')
"denoise": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/denoise\.gdshaderinc\"'),
"blur": RegEx.create_from_string(r'\s*\#include\s+\"res\:\/\/shaderlib\/blur\.gdshaderinc\"'),
}
const shaderlib_functions = {
"colorspaces": ["rgb2hsv", "hsv2rgb"],
"transform": ["place_texture"],
"transparency": ["alpha_blend"],
"effects": ["pixelate"],
"denoise": ["smart_denoise"]
"denoise": ["smart_denoise"],
"blur": ["gaussian_blur"],
}
#
# configure Highlighter