// Copyright (c) 2023 Lachlan McDonald
// This work is licensed under the MIT License (MIT)
// https://github.com/lachlanmcdonald/magicavoxel-shaders
//
// xs outline2 [Color]
//
// xs_begin
// author : '@lmcdx.bsky.social'
// arg : { name = 'Color'  var = 'm_color'  range = '0 255'  value = '1'  step = '1'  precision = '0' }
// xs_end

bool isSelectedPal(float p) {
	for (int i = 0; i < i_num_color_sels; i += 1) {
		if (p == color_sel(float(i))) {
			return true;
		}
	}
	return false;
}

float map(vec3 v) {
	float index = voxel(v);

	if (isSelectedPal(index)) {
		float n = voxel(vec3(v.x - 1.0, v.y, v.z));
		float s = voxel(vec3(v.x + 1.0, v.y, v.z));
		float e = voxel(vec3(v.x, v.y - 1.0, v.z));
		float w = voxel(vec3(v.x, v.y + 1.0, v.z));
		float a = voxel(vec3(v.x, v.y, v.z - 1.0));
		float b = voxel(vec3(v.x, v.y, v.z + 1.0));

		if ((isSelectedPal(n) == false && n != 0.0) ||
			(isSelectedPal(s) == false && s != 0.0) ||
			(isSelectedPal(e) == false && e != 0.0) ||
			(isSelectedPal(w) == false && w != 0.0) ||
			(isSelectedPal(a) == false && a != 0.0) ||
			(isSelectedPal(b) == false && b != 0.0)) {
			return m_color;
		}
	}
	return index;
}