Pixelated burn

Heavily inspired by these two shaders
https://godotshaders.com/shader/burn-sprite/
https://godotshaders.com/shader/2d-burn-dissolve-from-point-v-1-0/

I needed something like this but which had both effects (from one point and multiple colors) and also was pixelated, so that it could fit better with pixel art.

Shader code

shader_type canvas_item;

uniform vec2 position;
uniform float radius;
uniform float borderWidth = 0.2;
uniform float burnMult = 0.34;
uniform sampler2D noiseTexture;
uniform vec4 burnColor : source_color;
uniform float pixel_size = 0.004;
uniform float blend_steps = 8.5; // lower number = more saturated

uniform sampler2D colorCurve;


void fragment() {
    vec2 snapped_uv = floor(UV / pixel_size) * pixel_size;

    float dist = length(position - snapped_uv) + (texture(noiseTexture, snapped_uv).b) * burnMult;
    float mask = clamp((dist - (radius - borderWidth)) / (2.0 * borderWidth), 0.0, 1.0);
    mask = 1.0 - mask;
    mask = floor(mask * blend_steps) / blend_steps;
	
    vec4 curve_value = texture(colorCurve, vec2(mask, 0.0));
    
    float blendMask = pow(mask, 0.1); 
    COLOR.rgb = mix(COLOR.rgb, curve_value.rgb, blendMask);
    
	COLOR.a *= min(COLOR.a,1.0-(float(dist<radius)));
}

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