Shader Pallet Swap Godot 4 (ColorRect)

Shader Pallet Swap  Godot 4 (ColorRect)

shader_type canvas_item;

uniform vec4 color_white_like : source_color = vec4(0.820, 0.846, 0.705, 1.0); // tom mais claro (quase branco)
uniform vec4 color_light     : source_color = vec4(0.538, 0.559, 0.458, 1.0); // claro
uniform vec4 color_mid       : source_color = vec4(0.383, 0.403, 0.314, 1.0); // médio
uniform vec4 color_dark      : source_color = vec4(0.258, 0.272, 0.214, 1.0); // escuro
uniform vec4 color_near_black: source_color = vec4(0.124, 0.125, 0.121, 1.0); // quase preto

uniform sampler2D SCREEN_TEXTURE : hint_screen_texture, filter_linear_mipmap;

float min5(float a, float b, float c, float d, float e){
    return min(a, min(b, min(c, min(d, e))));
}

void fragment(){
    vec4 currentColor = texture(SCREEN_TEXTURE, SCREEN_UV);

    // Referência em tons de cinza (usamos 5 níveis de luminância como base)
    float d_white = distance(currentColor, vec4(vec3(1.0), 1.0));   // mais claro (branco)
    float d_light = distance(currentColor, vec4(vec3(0.75), 1.0));  // claro
    float d_mid   = distance(currentColor, vec4(vec3(0.50), 1.0));  // médio
    float d_dark  = distance(currentColor, vec4(vec3(0.25), 1.0));  // escuro
    float d_black = distance(currentColor, vec4(vec3(0.0), 1.0));   // preto

    float m = min5(d_white, d_light, d_mid, d_dark, d_black);

    if (m == d_white)      COLOR = color_white_like;
    else if (m == d_light) COLOR = color_light;
    else if (m == d_mid)   COLOR = color_mid;
    else if (m == d_dark)  COLOR = color_dark;
    else                   COLOR = color_near_black;
}