Glow effect 2D

This shader allows you to make a part of a sprite glow without having to make a light mask

you have source colors these are the colors of the pixels you want to glow

the threshold value is a sensivity

the intensity is the strength of the glow

and the opacity allows to see the original sprite under it

oh and of course the glow color you want

if you’re new with Godot you’ll need a worldenvironment node with “glow” checked for this to work.

Shader code

shader_type canvas_item;

uniform vec4 color1 : source_color;
uniform vec4 color2 : source_color;
uniform float threshold;
uniform float intensity;
uniform float opacity;
uniform vec4 glow_color : source_color;

void fragment() {
	// Get the pixel color from the texture
	vec4 pixel_color = texture(TEXTURE, UV);
	
	// Calculate the distance between the pixel color and the first source color
	float distance = length(pixel_color - color1);
	
	// Calculate the distance between the pixel color and the second source color
	float distance_second = length(pixel_color - color2);
	
	// Create a new variable to store the modified glow color
	vec4 modified_glow_color = glow_color;
	
	// Set the alpha value of the modified glow color to the specified opacity
	modified_glow_color.a = opacity;
	
	// If the distance to either source color is below the threshold, set the output color to a blend of the pixel color and the modified glow color
	if (distance < threshold || distance_second < threshold) {
		COLOR = mix(pixel_color, modified_glow_color * intensity, modified_glow_color.a);
	}
	// Otherwise, set the output color to the pixel color
	else {
		COLOR = pixel_color;
	}
}