// Copyright (c) 2023 Lachlan McDonald
// This work is licensed under the MIT License (MIT)
// https://github.com/lachlanmcdonald/magicavoxel-shaders
//
// xs brush/grid [Color A] [Color B] [Thickness] [Size X] [Size Y] [Size Z]
//
// xs_begin
// author : '@lmcdx.bsky.social'
// arg : { name = 'Color A'  var = 'm_color_a'  range = '0 255'  value = '1'  step = '1'  precision = '0' }
// arg : { name = 'Color B'  var = 'm_color_b'  range = '0 255'  value = '2'  step = '1'  precision = '0' }
// arg : { name = 'Thickness'  var = 'm_thickness'  range = '1 256'  value = '1'  step = '1'  precision = '0' }
// arg : { name = 'Size X'  var = 'm_size_x'  range = '1 256'  value = '4'  step = '1'  precision = '0' }
// arg : { name = 'Size Y'  var = 'm_size_y'  range = '1 256'  value = '4'  step = '1'  precision = '0' }
// arg : { name = 'Size Z'  var = 'm_size_z'  range = '1 256'  value = '4'  step = '1'  precision = '0' }
// xs_end

float thickness = m_thickness - 1.0;
vec3 dim = vec3(m_size_x, m_size_y, m_size_z) + 1.0;

bool no_axis_mode = all(equal(ivec3(i_axis), ivec3(0)));
bvec3 axis_mode = no_axis_mode ? bvec3(true) : equal(ivec3(i_axis), ivec3(1));

float map(vec3 v) {
	if (axis_mode.x) {
		if (dim.x > thickness) {
			float m = floor(mod(v.x, dim.x));

			if (m <= thickness) {
				return m_color_a;
			}
		}
	}
	if (axis_mode.y) {
		if (dim.y > thickness) {
			float m = floor(mod(v.y, dim.y));

			if (m <= thickness) {
				return m_color_a;
			}
		}
	}
	if (axis_mode.z) {
		if (dim.z > thickness) {
			float m = floor(mod(v.z, dim.z));

			if (m <= thickness) {
				return m_color_a;
			}
		}
	}

	return m_color_b;
}