// Copyright (c) 2022 Lachlan McDonald
// This work is licensed under the MIT License (MIT)
// https://github.com/lachlanmcdonald/magicavoxel-shaders
//
// xs_begin
// author : '@lachlanmcdonald'
// arg : { name = 'Spacing'  var = 'm_spacing'  range = '1 100'  value = '1'  step = '1'  precision = '0' }
// xs_end

float spacing = floor(m_spacing + 1.0);
bvec3 axis_mode = equal(ivec3(i_axis), ivec3(1));

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

	if (axis_mode.x) {
		int x = int(mod(v.x, spacing));
		return x == 0 ? voxel(vec3(floor(v.x / spacing), v.yz)) : 0.0;
	} else if (axis_mode.y) {
		int y = int(mod(v.y, spacing));
		return y == 0 ? voxel(vec3(v.x, floor(v.y / spacing), v.z)) : 0.0;
	} else if (axis_mode.z) {
		int z = int(mod(v.z, spacing));
		return z == 0 ? voxel(vec3(v.xy, floor(v.z / spacing))) : 0.0;
	} else {
		return index;
	}
}