godot/scene/3d/voxelizer.cpp
2023-10-09 12:27:03 +03:00

1015 lines
28 KiB
C++

/**************************************************************************/
/* voxelizer.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "voxelizer.h"
#include "core/config/project_settings.h"
static _FORCE_INLINE_ void get_uv_and_normal(const Vector3 &p_pos, const Vector3 *p_vtx, const Vector2 *p_uv, const Vector3 *p_normal, Vector2 &r_uv, Vector3 &r_normal) {
if (p_pos.is_equal_approx(p_vtx[0])) {
r_uv = p_uv[0];
r_normal = p_normal[0];
return;
}
if (p_pos.is_equal_approx(p_vtx[1])) {
r_uv = p_uv[1];
r_normal = p_normal[1];
return;
}
if (p_pos.is_equal_approx(p_vtx[2])) {
r_uv = p_uv[2];
r_normal = p_normal[2];
return;
}
Vector3 v0 = p_vtx[1] - p_vtx[0];
Vector3 v1 = p_vtx[2] - p_vtx[0];
Vector3 v2 = p_pos - p_vtx[0];
real_t d00 = v0.dot(v0);
real_t d01 = v0.dot(v1);
real_t d11 = v1.dot(v1);
real_t d20 = v2.dot(v0);
real_t d21 = v2.dot(v1);
real_t denom = (d00 * d11 - d01 * d01);
if (denom == 0) {
r_uv = p_uv[0];
r_normal = p_normal[0];
return;
}
real_t v = (d11 * d20 - d01 * d21) / denom;
real_t w = (d00 * d21 - d01 * d20) / denom;
real_t u = 1.0f - v - w;
r_uv = p_uv[0] * u + p_uv[1] * v + p_uv[2] * w;
r_normal = (p_normal[0] * u + p_normal[1] * v + p_normal[2] * w).normalized();
}
void Voxelizer::_plot_face(int p_idx, int p_level, int p_x, int p_y, int p_z, const Vector3 *p_vtx, const Vector3 *p_normal, const Vector2 *p_uv, const MaterialCache &p_material, const AABB &p_aabb) {
if (p_level == cell_subdiv) {
//plot the face by guessing its albedo and emission value
//find best axis to map to, for scanning values
int closest_axis = 0;
real_t closest_dot = 0;
Plane plane = Plane(p_vtx[0], p_vtx[1], p_vtx[2]);
Vector3 normal = plane.normal;
for (int i = 0; i < 3; i++) {
Vector3 axis;
axis[i] = 1.0;
real_t dot = ABS(normal.dot(axis));
if (i == 0 || dot > closest_dot) {
closest_axis = i;
closest_dot = dot;
}
}
Vector3 axis;
axis[closest_axis] = 1.0;
Vector3 t1;
t1[(closest_axis + 1) % 3] = 1.0;
Vector3 t2;
t2[(closest_axis + 2) % 3] = 1.0;
t1 *= p_aabb.size[(closest_axis + 1) % 3] / real_t(color_scan_cell_width);
t2 *= p_aabb.size[(closest_axis + 2) % 3] / real_t(color_scan_cell_width);
Color albedo_accum;
Color emission_accum;
Vector3 normal_accum;
float alpha = 0.0;
//map to a grid average in the best axis for this face
for (int i = 0; i < color_scan_cell_width; i++) {
Vector3 ofs_i = real_t(i) * t1;
for (int j = 0; j < color_scan_cell_width; j++) {
Vector3 ofs_j = real_t(j) * t2;
Vector3 from = p_aabb.position + ofs_i + ofs_j;
Vector3 to = from + t1 + t2 + axis * p_aabb.size[closest_axis];
Vector3 half = (to - from) * 0.5;
//is in this cell?
if (!Geometry3D::triangle_box_overlap(from + half, half, p_vtx)) {
continue; //face does not span this cell
}
//go from -size to +size*2 to avoid skipping collisions
Vector3 ray_from = from + (t1 + t2) * 0.5 - axis * p_aabb.size[closest_axis];
Vector3 ray_to = ray_from + axis * p_aabb.size[closest_axis] * 2;
if (normal.dot(ray_from - ray_to) < 0) {
SWAP(ray_from, ray_to);
}
Vector3 intersection;
if (!plane.intersects_segment(ray_from, ray_to, &intersection)) {
if (ABS(plane.distance_to(ray_from)) < ABS(plane.distance_to(ray_to))) {
intersection = plane.project(ray_from);
} else {
intersection = plane.project(ray_to);
}
}
intersection = Face3(p_vtx[0], p_vtx[1], p_vtx[2]).get_closest_point_to(intersection);
Vector2 uv;
Vector3 lnormal;
get_uv_and_normal(intersection, p_vtx, p_uv, p_normal, uv, lnormal);
if (lnormal == Vector3()) { //just in case normal is not provided
lnormal = normal;
}
int uv_x = CLAMP(int(Math::fposmod(uv.x, (real_t)1.0) * bake_texture_size), 0, bake_texture_size - 1);
int uv_y = CLAMP(int(Math::fposmod(uv.y, (real_t)1.0) * bake_texture_size), 0, bake_texture_size - 1);
int ofs = uv_y * bake_texture_size + uv_x;
albedo_accum.r += p_material.albedo[ofs].r;
albedo_accum.g += p_material.albedo[ofs].g;
albedo_accum.b += p_material.albedo[ofs].b;
albedo_accum.a += p_material.albedo[ofs].a;
emission_accum.r += p_material.emission[ofs].r;
emission_accum.g += p_material.emission[ofs].g;
emission_accum.b += p_material.emission[ofs].b;
normal_accum += lnormal;
alpha += 1.0;
}
}
if (alpha == 0) {
//could not in any way get texture information.. so use closest point to center
Face3 f(p_vtx[0], p_vtx[1], p_vtx[2]);
Vector3 inters = f.get_closest_point_to(p_aabb.get_center());
Vector3 lnormal;
Vector2 uv;
get_uv_and_normal(inters, p_vtx, p_uv, p_normal, uv, normal);
if (lnormal == Vector3()) { //just in case normal is not provided
lnormal = normal;
}
int uv_x = CLAMP(Math::fposmod(uv.x, (real_t)1.0) * bake_texture_size, 0, bake_texture_size - 1);
int uv_y = CLAMP(Math::fposmod(uv.y, (real_t)1.0) * bake_texture_size, 0, bake_texture_size - 1);
int ofs = uv_y * bake_texture_size + uv_x;
alpha = 1.0 / (color_scan_cell_width * color_scan_cell_width);
albedo_accum.r = p_material.albedo[ofs].r * alpha;
albedo_accum.g = p_material.albedo[ofs].g * alpha;
albedo_accum.b = p_material.albedo[ofs].b * alpha;
albedo_accum.a = p_material.albedo[ofs].a * alpha;
emission_accum.r = p_material.emission[ofs].r * alpha;
emission_accum.g = p_material.emission[ofs].g * alpha;
emission_accum.b = p_material.emission[ofs].b * alpha;
normal_accum = lnormal * alpha;
} else {
float accdiv = 1.0 / (color_scan_cell_width * color_scan_cell_width);
alpha *= accdiv;
albedo_accum.r *= accdiv;
albedo_accum.g *= accdiv;
albedo_accum.b *= accdiv;
albedo_accum.a *= accdiv;
emission_accum.r *= accdiv;
emission_accum.g *= accdiv;
emission_accum.b *= accdiv;
normal_accum *= accdiv;
}
//put this temporarily here, corrected in a later step
bake_cells.write[p_idx].albedo[0] += albedo_accum.r;
bake_cells.write[p_idx].albedo[1] += albedo_accum.g;
bake_cells.write[p_idx].albedo[2] += albedo_accum.b;
bake_cells.write[p_idx].emission[0] += emission_accum.r;
bake_cells.write[p_idx].emission[1] += emission_accum.g;
bake_cells.write[p_idx].emission[2] += emission_accum.b;
bake_cells.write[p_idx].normal[0] += normal_accum.x;
bake_cells.write[p_idx].normal[1] += normal_accum.y;
bake_cells.write[p_idx].normal[2] += normal_accum.z;
bake_cells.write[p_idx].alpha += alpha;
} else {
//go down
int half = (1 << cell_subdiv) >> (p_level + 1);
for (int i = 0; i < 8; i++) {
AABB aabb = p_aabb;
aabb.size *= 0.5;
int nx = p_x;
int ny = p_y;
int nz = p_z;
if (i & 1) {
aabb.position.x += aabb.size.x;
nx += half;
}
if (i & 2) {
aabb.position.y += aabb.size.y;
ny += half;
}
if (i & 4) {
aabb.position.z += aabb.size.z;
nz += half;
}
//make sure to not plot beyond limits
if (nx < 0 || nx >= axis_cell_size[0] || ny < 0 || ny >= axis_cell_size[1] || nz < 0 || nz >= axis_cell_size[2]) {
continue;
}
{
AABB test_aabb = aabb;
//test_aabb.grow_by(test_aabb.get_longest_axis_size()*0.05); //grow a bit to avoid numerical error in real-time
Vector3 qsize = test_aabb.size * 0.5; //quarter size, for fast aabb test
if (!Geometry3D::triangle_box_overlap(test_aabb.position + qsize, qsize, p_vtx)) {
//if (!Face3(p_vtx[0],p_vtx[1],p_vtx[2]).intersects_aabb2(aabb)) {
//does not fit in child, go on
continue;
}
}
if (bake_cells[p_idx].children[i] == CHILD_EMPTY) {
//sub cell must be created
uint32_t child_idx = bake_cells.size();
bake_cells.write[p_idx].children[i] = child_idx;
bake_cells.resize(bake_cells.size() + 1);
bake_cells.write[child_idx].level = p_level + 1;
bake_cells.write[child_idx].x = nx / half;
bake_cells.write[child_idx].y = ny / half;
bake_cells.write[child_idx].z = nz / half;
}
_plot_face(bake_cells[p_idx].children[i], p_level + 1, nx, ny, nz, p_vtx, p_normal, p_uv, p_material, aabb);
}
}
}
Vector<Color> Voxelizer::_get_bake_texture(Ref<Image> p_image, const Color &p_color_mul, const Color &p_color_add) {
Vector<Color> ret;
if (p_image.is_null() || p_image->is_empty()) {
ret.resize(bake_texture_size * bake_texture_size);
for (int i = 0; i < bake_texture_size * bake_texture_size; i++) {
ret.write[i] = p_color_add;
}
return ret;
}
p_image = p_image->duplicate();
if (p_image->is_compressed()) {
p_image->decompress();
}
p_image->convert(Image::FORMAT_RGBA8);
p_image->resize(bake_texture_size, bake_texture_size, Image::INTERPOLATE_CUBIC);
const uint8_t *r = p_image->get_data().ptr();
ret.resize(bake_texture_size * bake_texture_size);
for (int i = 0; i < bake_texture_size * bake_texture_size; i++) {
Color c;
c.r = (r[i * 4 + 0] / 255.0) * p_color_mul.r + p_color_add.r;
c.g = (r[i * 4 + 1] / 255.0) * p_color_mul.g + p_color_add.g;
c.b = (r[i * 4 + 2] / 255.0) * p_color_mul.b + p_color_add.b;
c.a = r[i * 4 + 3] / 255.0;
ret.write[i] = c;
}
return ret;
}
Voxelizer::MaterialCache Voxelizer::_get_material_cache(Ref<Material> p_material) {
// This way of obtaining materials is inaccurate and also does not support some compressed formats very well.
Ref<BaseMaterial3D> mat = p_material;
Ref<Material> material = mat; //hack for now
if (material_cache.has(material)) {
return material_cache[material];
}
MaterialCache mc;
if (mat.is_valid()) {
Ref<Texture2D> albedo_tex = mat->get_texture(BaseMaterial3D::TEXTURE_ALBEDO);
Ref<Image> img_albedo;
if (albedo_tex.is_valid()) {
img_albedo = albedo_tex->get_image();
mc.albedo = _get_bake_texture(img_albedo, mat->get_albedo(), Color(0, 0, 0)); // albedo texture, color is multiplicative
} else {
mc.albedo = _get_bake_texture(img_albedo, Color(1, 1, 1), mat->get_albedo()); // no albedo texture, color is additive
}
if (mat->get_feature(BaseMaterial3D::FEATURE_EMISSION)) {
Ref<Texture2D> emission_tex = mat->get_texture(BaseMaterial3D::TEXTURE_EMISSION);
Color emission_col = mat->get_emission();
float emission_energy = mat->get_emission_energy_multiplier() * exposure_normalization;
if (GLOBAL_GET("rendering/lights_and_shadows/use_physical_light_units")) {
emission_energy *= mat->get_emission_intensity();
}
Ref<Image> img_emission;
if (emission_tex.is_valid()) {
img_emission = emission_tex->get_image();
}
if (mat->get_emission_operator() == BaseMaterial3D::EMISSION_OP_ADD) {
mc.emission = _get_bake_texture(img_emission, Color(1, 1, 1) * emission_energy, emission_col * emission_energy);
} else {
mc.emission = _get_bake_texture(img_emission, emission_col * emission_energy, Color(0, 0, 0));
}
} else {
Ref<Image> empty;
mc.emission = _get_bake_texture(empty, Color(0, 0, 0), Color(0, 0, 0));
}
} else {
Ref<Image> empty;
mc.albedo = _get_bake_texture(empty, Color(0, 0, 0), Color(1, 1, 1));
mc.emission = _get_bake_texture(empty, Color(0, 0, 0), Color(0, 0, 0));
}
material_cache[p_material] = mc;
return mc;
}
void Voxelizer::plot_mesh(const Transform3D &p_xform, Ref<Mesh> &p_mesh, const Vector<Ref<Material>> &p_materials, const Ref<Material> &p_override_material) {
for (int i = 0; i < p_mesh->get_surface_count(); i++) {
if (p_mesh->surface_get_primitive_type(i) != Mesh::PRIMITIVE_TRIANGLES) {
continue; //only triangles
}
Ref<Material> src_material;
if (p_override_material.is_valid()) {
src_material = p_override_material;
} else if (i < p_materials.size() && p_materials[i].is_valid()) {
src_material = p_materials[i];
} else {
src_material = p_mesh->surface_get_material(i);
}
MaterialCache material = _get_material_cache(src_material);
Array a = p_mesh->surface_get_arrays(i);
Vector<Vector3> vertices = a[Mesh::ARRAY_VERTEX];
const Vector3 *vr = vertices.ptr();
Vector<Vector2> uv = a[Mesh::ARRAY_TEX_UV];
const Vector2 *uvr = nullptr;
Vector<Vector3> normals = a[Mesh::ARRAY_NORMAL];
const Vector3 *nr = nullptr;
Vector<int> index = a[Mesh::ARRAY_INDEX];
if (uv.size()) {
uvr = uv.ptr();
}
if (normals.size()) {
nr = normals.ptr();
}
if (index.size()) {
int facecount = index.size() / 3;
const int *ir = index.ptr();
for (int j = 0; j < facecount; j++) {
Vector3 vtxs[3];
Vector2 uvs[3];
Vector3 normal[3];
for (int k = 0; k < 3; k++) {
vtxs[k] = p_xform.xform(vr[ir[j * 3 + k]]);
}
if (uvr) {
for (int k = 0; k < 3; k++) {
uvs[k] = uvr[ir[j * 3 + k]];
}
}
if (nr) {
for (int k = 0; k < 3; k++) {
normal[k] = nr[ir[j * 3 + k]];
}
}
//test against original bounds
if (!Geometry3D::triangle_box_overlap(original_bounds.get_center(), original_bounds.size * 0.5, vtxs)) {
continue;
}
//plot
_plot_face(0, 0, 0, 0, 0, vtxs, normal, uvs, material, po2_bounds);
}
} else {
int facecount = vertices.size() / 3;
for (int j = 0; j < facecount; j++) {
Vector3 vtxs[3];
Vector2 uvs[3];
Vector3 normal[3];
for (int k = 0; k < 3; k++) {
vtxs[k] = p_xform.xform(vr[j * 3 + k]);
}
if (uvr) {
for (int k = 0; k < 3; k++) {
uvs[k] = uvr[j * 3 + k];
}
}
if (nr) {
for (int k = 0; k < 3; k++) {
normal[k] = nr[j * 3 + k];
}
}
//test against original bounds
if (!Geometry3D::triangle_box_overlap(original_bounds.get_center(), original_bounds.size * 0.5, vtxs)) {
continue;
}
//plot face
_plot_face(0, 0, 0, 0, 0, vtxs, normal, uvs, material, po2_bounds);
}
}
}
max_original_cells = bake_cells.size();
}
void Voxelizer::_sort() {
// cells need to be sorted by level and coordinates
// it is important that level has more priority (for compute), and that Z has the least,
// given it may aid older implementations plot using GPU
Vector<CellSort> sorted_cells;
uint32_t cell_count = bake_cells.size();
sorted_cells.resize(cell_count);
{
CellSort *sort_cellsp = sorted_cells.ptrw();
const Cell *bake_cellsp = bake_cells.ptr();
for (uint32_t i = 0; i < cell_count; i++) {
sort_cellsp[i].x = bake_cellsp[i].x;
sort_cellsp[i].y = bake_cellsp[i].y;
sort_cellsp[i].z = bake_cellsp[i].z;
sort_cellsp[i].level = bake_cellsp[i].level;
sort_cellsp[i].index = i;
}
}
sorted_cells.sort();
//verify just in case, index 0 must be level 0
ERR_FAIL_COND(sorted_cells[0].level != 0);
Vector<Cell> new_bake_cells;
new_bake_cells.resize(cell_count);
Vector<uint32_t> reverse_map;
{
reverse_map.resize(cell_count);
const CellSort *sort_cellsp = sorted_cells.ptr();
uint32_t *reverse_mapp = reverse_map.ptrw();
for (uint32_t i = 0; i < cell_count; i++) {
reverse_mapp[sort_cellsp[i].index] = i;
}
}
{
const CellSort *sort_cellsp = sorted_cells.ptr();
const Cell *bake_cellsp = bake_cells.ptr();
const uint32_t *reverse_mapp = reverse_map.ptr();
Cell *new_bake_cellsp = new_bake_cells.ptrw();
for (uint32_t i = 0; i < cell_count; i++) {
//copy to new cell
new_bake_cellsp[i] = bake_cellsp[sort_cellsp[i].index];
//remap children
for (uint32_t j = 0; j < 8; j++) {
if (new_bake_cellsp[i].children[j] != CHILD_EMPTY) {
new_bake_cellsp[i].children[j] = reverse_mapp[new_bake_cellsp[i].children[j]];
}
}
}
}
bake_cells = new_bake_cells;
sorted = true;
}
void Voxelizer::_fixup_plot(int p_idx, int p_level) {
if (p_level == cell_subdiv) {
leaf_voxel_count++;
float alpha = bake_cells[p_idx].alpha;
bake_cells.write[p_idx].albedo[0] /= alpha;
bake_cells.write[p_idx].albedo[1] /= alpha;
bake_cells.write[p_idx].albedo[2] /= alpha;
//transfer emission to light
bake_cells.write[p_idx].emission[0] /= alpha;
bake_cells.write[p_idx].emission[1] /= alpha;
bake_cells.write[p_idx].emission[2] /= alpha;
bake_cells.write[p_idx].normal[0] /= alpha;
bake_cells.write[p_idx].normal[1] /= alpha;
bake_cells.write[p_idx].normal[2] /= alpha;
Vector3 n(bake_cells[p_idx].normal[0], bake_cells[p_idx].normal[1], bake_cells[p_idx].normal[2]);
if (n.length() < 0.01) {
//too much fight over normal, zero it
bake_cells.write[p_idx].normal[0] = 0;
bake_cells.write[p_idx].normal[1] = 0;
bake_cells.write[p_idx].normal[2] = 0;
} else {
n.normalize();
bake_cells.write[p_idx].normal[0] = n.x;
bake_cells.write[p_idx].normal[1] = n.y;
bake_cells.write[p_idx].normal[2] = n.z;
}
bake_cells.write[p_idx].alpha = 1.0;
/*if (bake_light.size()) {
for(int i=0;i<6;i++) {
}
}*/
} else {
//go down
bake_cells.write[p_idx].emission[0] = 0;
bake_cells.write[p_idx].emission[1] = 0;
bake_cells.write[p_idx].emission[2] = 0;
bake_cells.write[p_idx].normal[0] = 0;
bake_cells.write[p_idx].normal[1] = 0;
bake_cells.write[p_idx].normal[2] = 0;
bake_cells.write[p_idx].albedo[0] = 0;
bake_cells.write[p_idx].albedo[1] = 0;
bake_cells.write[p_idx].albedo[2] = 0;
float alpha_average = 0;
for (int i = 0; i < 8; i++) {
uint32_t child = bake_cells[p_idx].children[i];
if (child == CHILD_EMPTY) {
continue;
}
_fixup_plot(child, p_level + 1);
alpha_average += bake_cells[child].alpha;
}
bake_cells.write[p_idx].alpha = alpha_average / 8.0;
}
}
void Voxelizer::begin_bake(int p_subdiv, const AABB &p_bounds, float p_exposure_normalization) {
sorted = false;
original_bounds = p_bounds;
cell_subdiv = p_subdiv;
exposure_normalization = p_exposure_normalization;
bake_cells.resize(1);
material_cache.clear();
//find out the actual real bounds, power of 2, which gets the highest subdivision
po2_bounds = p_bounds;
int longest_axis = po2_bounds.get_longest_axis_index();
axis_cell_size[longest_axis] = 1 << cell_subdiv;
leaf_voxel_count = 0;
for (int i = 0; i < 3; i++) {
if (i == longest_axis) {
continue;
}
axis_cell_size[i] = axis_cell_size[longest_axis];
real_t axis_size = po2_bounds.size[longest_axis];
//shrink until fit subdiv
while (axis_size / 2.0 >= po2_bounds.size[i]) {
axis_size /= 2.0;
axis_cell_size[i] >>= 1;
}
po2_bounds.size[i] = po2_bounds.size[longest_axis];
}
Transform3D to_bounds;
to_bounds.basis.scale(Vector3(po2_bounds.size[longest_axis], po2_bounds.size[longest_axis], po2_bounds.size[longest_axis]));
to_bounds.origin = po2_bounds.position;
Transform3D to_grid;
to_grid.basis.scale(Vector3(axis_cell_size[longest_axis], axis_cell_size[longest_axis], axis_cell_size[longest_axis]));
to_cell_space = to_grid * to_bounds.affine_inverse();
cell_size = po2_bounds.size[longest_axis] / axis_cell_size[longest_axis];
}
void Voxelizer::end_bake() {
if (!sorted) {
_sort();
}
_fixup_plot(0, 0);
}
//create the data for rendering server
int Voxelizer::get_voxel_gi_octree_depth() const {
return cell_subdiv;
}
Vector3i Voxelizer::get_voxel_gi_octree_size() const {
return Vector3i(axis_cell_size[0], axis_cell_size[1], axis_cell_size[2]);
}
int Voxelizer::get_voxel_gi_cell_count() const {
return bake_cells.size();
}
Vector<uint8_t> Voxelizer::get_voxel_gi_octree_cells() const {
Vector<uint8_t> data;
data.resize((8 * 4) * bake_cells.size()); //8 uint32t values
{
uint8_t *w = data.ptrw();
uint32_t *children_cells = (uint32_t *)w;
const Cell *cells = bake_cells.ptr();
uint32_t cell_count = bake_cells.size();
for (uint32_t i = 0; i < cell_count; i++) {
for (uint32_t j = 0; j < 8; j++) {
children_cells[i * 8 + j] = cells[i].children[j];
}
}
}
return data;
}
Vector<uint8_t> Voxelizer::get_voxel_gi_data_cells() const {
Vector<uint8_t> data;
data.resize((4 * 4) * bake_cells.size()); //8 uint32t values
{
uint8_t *w = data.ptrw();
uint32_t *dataptr = (uint32_t *)w;
const Cell *cells = bake_cells.ptr();
uint32_t cell_count = bake_cells.size();
for (uint32_t i = 0; i < cell_count; i++) {
{ //position
uint32_t x = cells[i].x;
uint32_t y = cells[i].y;
uint32_t z = cells[i].z;
uint32_t position = x;
position |= y << 11;
position |= z << 21;
dataptr[i * 4 + 0] = position;
}
{ //albedo + alpha
uint32_t rgba = uint32_t(CLAMP(cells[i].alpha * 255.0, 0, 255)) << 24; //a
rgba |= uint32_t(CLAMP(cells[i].albedo[2] * 255.0, 0, 255)) << 16; //b
rgba |= uint32_t(CLAMP(cells[i].albedo[1] * 255.0, 0, 255)) << 8; //g
rgba |= uint32_t(CLAMP(cells[i].albedo[0] * 255.0, 0, 255)); //r
dataptr[i * 4 + 1] = rgba;
}
{ //emission, as rgbe9995
Color emission = Color(cells[i].emission[0], cells[i].emission[1], cells[i].emission[2]);
dataptr[i * 4 + 2] = emission.to_rgbe9995();
}
{ //normal
Vector3 n(bake_cells[i].normal[0], bake_cells[i].normal[1], bake_cells[i].normal[2]);
n.normalize();
uint32_t normal = uint32_t(uint8_t(int8_t(CLAMP(n.x * 127.0, -128, 127))));
normal |= uint32_t(uint8_t(int8_t(CLAMP(n.y * 127.0, -128, 127)))) << 8;
normal |= uint32_t(uint8_t(int8_t(CLAMP(n.z * 127.0, -128, 127)))) << 16;
dataptr[i * 4 + 3] = normal;
}
}
}
return data;
}
Vector<int> Voxelizer::get_voxel_gi_level_cell_count() const {
uint32_t cell_count = bake_cells.size();
const Cell *cells = bake_cells.ptr();
Vector<int> level_count;
level_count.resize(cell_subdiv + 1); //remember, always x+1 levels for x subdivisions
{
int *w = level_count.ptrw();
for (int i = 0; i < cell_subdiv + 1; i++) {
w[i] = 0;
}
for (uint32_t i = 0; i < cell_count; i++) {
w[cells[i].level]++;
}
}
return level_count;
}
// euclidean distance computation based on:
// https://prideout.net/blog/distance_fields/
#define square(m_s) ((m_s) * (m_s))
#define INF 1e20
/* dt of 1d function using squared distance */
static void edt(float *f, int stride, int n) {
float *d = (float *)alloca(sizeof(float) * n + sizeof(int) * n + sizeof(float) * (n + 1));
int *v = reinterpret_cast<int *>(&(d[n]));
float *z = reinterpret_cast<float *>(&v[n]);
int k = 0;
v[0] = 0;
z[0] = -INF;
z[1] = +INF;
for (int q = 1; q <= n - 1; q++) {
float s = ((f[q * stride] + square(q)) - (f[v[k] * stride] + square(v[k]))) / (2 * q - 2 * v[k]);
while (s <= z[k]) {
k--;
s = ((f[q * stride] + square(q)) - (f[v[k] * stride] + square(v[k]))) / (2 * q - 2 * v[k]);
}
k++;
v[k] = q;
z[k] = s;
z[k + 1] = +INF;
}
k = 0;
for (int q = 0; q <= n - 1; q++) {
while (z[k + 1] < q) {
k++;
}
d[q] = square(q - v[k]) + f[v[k] * stride];
}
for (int i = 0; i < n; i++) {
f[i * stride] = d[i];
}
}
#undef square
Vector<uint8_t> Voxelizer::get_sdf_3d_image() const {
Vector3i octree_size = get_voxel_gi_octree_size();
uint32_t float_count = octree_size.x * octree_size.y * octree_size.z;
float *work_memory = memnew_arr(float, float_count);
for (uint32_t i = 0; i < float_count; i++) {
work_memory[i] = INF;
}
uint32_t y_mult = octree_size.x;
uint32_t z_mult = y_mult * octree_size.y;
//plot solid cells
{
const Cell *cells = bake_cells.ptr();
uint32_t cell_count = bake_cells.size();
for (uint32_t i = 0; i < cell_count; i++) {
if (cells[i].level < (cell_subdiv - 1)) {
continue; //do not care about this level
}
work_memory[cells[i].x + cells[i].y * y_mult + cells[i].z * z_mult] = 0;
}
}
//process in each direction
//xy->z
for (int i = 0; i < octree_size.x; i++) {
for (int j = 0; j < octree_size.y; j++) {
edt(&work_memory[i + j * y_mult], z_mult, octree_size.z);
}
}
//xz->y
for (int i = 0; i < octree_size.x; i++) {
for (int j = 0; j < octree_size.z; j++) {
edt(&work_memory[i + j * z_mult], y_mult, octree_size.y);
}
}
//yz->x
for (int i = 0; i < octree_size.y; i++) {
for (int j = 0; j < octree_size.z; j++) {
edt(&work_memory[i * y_mult + j * z_mult], 1, octree_size.x);
}
}
Vector<uint8_t> image3d;
image3d.resize(float_count);
{
uint8_t *w = image3d.ptrw();
for (uint32_t i = 0; i < float_count; i++) {
uint32_t d = uint32_t(Math::sqrt(work_memory[i]));
if (d == 0) {
w[i] = 0;
} else {
w[i] = MIN(d, 254u) + 1;
}
}
}
memdelete_arr(work_memory);
return image3d;
}
#undef INF
void Voxelizer::_debug_mesh(int p_idx, int p_level, const AABB &p_aabb, Ref<MultiMesh> &p_multimesh, int &idx) {
if (p_level == cell_subdiv - 1) {
Vector3 center = p_aabb.get_center();
Transform3D xform;
xform.origin = center;
xform.basis.scale(p_aabb.size * 0.5);
p_multimesh->set_instance_transform(idx, xform);
Color col;
col = Color(bake_cells[p_idx].albedo[0], bake_cells[p_idx].albedo[1], bake_cells[p_idx].albedo[2]);
//Color col = Color(bake_cells[p_idx].emission[0], bake_cells[p_idx].emission[1], bake_cells[p_idx].emission[2]);
p_multimesh->set_instance_color(idx, col);
idx++;
} else {
for (int i = 0; i < 8; i++) {
uint32_t child = bake_cells[p_idx].children[i];
if (child == CHILD_EMPTY || child >= (uint32_t)max_original_cells) {
continue;
}
AABB aabb = p_aabb;
aabb.size *= 0.5;
if (i & 1) {
aabb.position.x += aabb.size.x;
}
if (i & 2) {
aabb.position.y += aabb.size.y;
}
if (i & 4) {
aabb.position.z += aabb.size.z;
}
_debug_mesh(bake_cells[p_idx].children[i], p_level + 1, aabb, p_multimesh, idx);
}
}
}
Ref<MultiMesh> Voxelizer::create_debug_multimesh() {
Ref<MultiMesh> mm;
mm.instantiate();
mm->set_transform_format(MultiMesh::TRANSFORM_3D);
mm->set_use_colors(true);
mm->set_instance_count(leaf_voxel_count);
Ref<ArrayMesh> mesh;
mesh.instantiate();
{
Array arr;
arr.resize(Mesh::ARRAY_MAX);
Vector<Vector3> vertices;
Vector<Color> colors;
#define ADD_VTX(m_idx) \
vertices.push_back(face_points[m_idx]); \
colors.push_back(Color(1, 1, 1, 1));
for (int i = 0; i < 6; i++) {
Vector3 face_points[4];
for (int j = 0; j < 4; j++) {
real_t v[3];
v[0] = 1.0;
v[1] = 1 - 2 * ((j >> 1) & 1);
v[2] = v[1] * (1 - 2 * (j & 1));
for (int k = 0; k < 3; k++) {
if (i < 3) {
face_points[j][(i + k) % 3] = v[k];
} else {
face_points[3 - j][(i + k) % 3] = -v[k];
}
}
}
//tri 1
ADD_VTX(0);
ADD_VTX(1);
ADD_VTX(2);
//tri 2
ADD_VTX(2);
ADD_VTX(3);
ADD_VTX(0);
}
arr[Mesh::ARRAY_VERTEX] = vertices;
arr[Mesh::ARRAY_COLOR] = colors;
mesh->add_surface_from_arrays(Mesh::PRIMITIVE_TRIANGLES, arr);
}
{
Ref<StandardMaterial3D> fsm;
fsm.instantiate();
fsm->set_flag(StandardMaterial3D::FLAG_SRGB_VERTEX_COLOR, true);
fsm->set_flag(StandardMaterial3D::FLAG_ALBEDO_FROM_VERTEX_COLOR, true);
fsm->set_shading_mode(StandardMaterial3D::SHADING_MODE_UNSHADED);
fsm->set_flag(StandardMaterial3D::FLAG_DISABLE_FOG, true);
fsm->set_albedo(Color(1, 1, 1, 1));
mesh->surface_set_material(0, fsm);
}
mm->set_mesh(mesh);
int idx = 0;
_debug_mesh(0, 0, po2_bounds, mm, idx);
return mm;
}
Transform3D Voxelizer::get_to_cell_space_xform() const {
return to_cell_space;
}
Voxelizer::Voxelizer() {
}