// Copyright (c) 2023 Lachlan McDonald
// This work is licensed under the MIT License (MIT)
// https://github.com/lachlanmcdonald/magicavoxel-shaders
//
// xs brush/zigzag2 [Direction] [Width A] [Width B]
//
// xs_begin
// author : '@lmcdx.bsky.social'
// arg : { name = 'Direction'  var = 'm_direction'  range = '0 3'  value = '0'  step = '1'  precision = '0' }
// arg : { name = 'Width A'  var = 'm_width_a'  range = '1 256'  value = '2'  step = '1'  precision = '0' }
// arg : { name = 'Width B'  var = 'm_width_b'  range = '1 256'  value = '2'  step = '1'  precision = '0' }
// xs_end

int direction = int(m_direction);

float map(vec3 v) {
	if (direction == 1) {
		v.y = -v.y;
	} else if (direction == 2) {
		v.x = -v.x;
		v.y = -v.y;
	} else if (direction == 3) {
		v.x = -v.x;
	}

	float size = m_width_a + m_width_b;
	vec3 c = floor(v / size);
	vec3 ic = floor(v - c * size);

	if (mod(c.x + c.y, 2.0) == 0.0) {
		if (any(lessThan(ic.xy, vec2(m_width_a)))) {
			return color_sel(0.0);
		} else {
			return i_num_color_sels < 2 ? 0.0 : color_sel(1.0);
		}
	} else {
		if (all(lessThan(ic.xy, vec2(m_width_a)))) {
			return color_sel(0.0);
		} else {
			return i_num_color_sels < 2 ? 0.0 : color_sel(1.0);
		}
	}
}