BambuStudio/src/libslic3r/Interlocking/InterlockingGenerator.cpp

334 lines
16 KiB
C++

// Copyright (c) 2023 UltiMaker
// CuraEngine is released under the terms of the AGPLv3 or higher.
#include "ClipperUtils.hpp"
#include "InterlockingGenerator.hpp"
#include "Layer.hpp"
namespace std {
template<> struct hash<Slic3r::GridPoint3>
{
size_t operator()(const Slic3r::GridPoint3& pp) const noexcept
{
static int prime = 31;
int result = 89;
result = static_cast<int>(result * prime + pp.x());
result = static_cast<int>(result * prime + pp.y());
result = static_cast<int>(result * prime + pp.z());
return static_cast<size_t>(result);
}
};
} // namespace std
namespace Slic3r {
void InterlockingGenerator::generate_interlocking_structure(PrintObject* print_object)
{
const auto& config = print_object->config();
if (!config.interlocking_beam) {
return;
}
const float rotation = Geometry::deg2rad(config.interlocking_orientation.value);
const coord_t beam_layer_count = config.interlocking_beam_layer_count;
const int interface_depth = config.interlocking_depth;
const int boundary_avoidance = config.interlocking_boundary_avoidance;
const coord_t beam_width = scaled(config.interlocking_beam_width.value);
const DilationKernel interface_dilation(GridPoint3(interface_depth, interface_depth, interface_depth), DilationKernel::Type::PRISM);
const bool air_filtering = boundary_avoidance > 0;
const DilationKernel air_dilation(GridPoint3(boundary_avoidance, boundary_avoidance, boundary_avoidance), DilationKernel::Type::PRISM);
const coord_t cell_width = beam_width + beam_width;
const Vec3crd cell_size(cell_width, cell_width, 2 * beam_layer_count);
for (size_t region_a_index = 0; region_a_index < print_object->num_printing_regions(); region_a_index++) {
const PrintRegion& region_a = print_object->printing_region(region_a_index);
const auto extruder_nr_a = region_a.extruder(FlowRole::frExternalPerimeter);
for (size_t region_b_index = region_a_index + 1; region_b_index < print_object->num_printing_regions(); region_b_index++) {
const PrintRegion& region_b = print_object->printing_region(region_b_index);
const auto extruder_nr_b = region_b.extruder(FlowRole::frExternalPerimeter);
if (extruder_nr_a == extruder_nr_b) {
continue;
}
InterlockingGenerator gen(*print_object, region_a_index, region_b_index, beam_width, boundary_avoidance, rotation, cell_size, beam_layer_count,
interface_dilation, air_dilation, air_filtering);
gen.generateInterlockingStructure();
}
}
}
std::pair<ExPolygons, ExPolygons> InterlockingGenerator::growBorderAreasPerpendicular(const ExPolygons& a, const ExPolygons& b, const coord_t& detect) const
{
const coord_t min_line =
std::min(print_object.printing_region(region_a_index).flow(print_object, frExternalPerimeter, 0.1).scaled_width(),
print_object.printing_region(region_b_index).flow(print_object, frExternalPerimeter, 0.1).scaled_width());
const ExPolygons total_shrunk = offset_ex(union_ex(offset_ex(a, min_line), offset_ex(b, min_line)), 2 * -min_line);
ExPolygons from_border_a = diff_ex(a, total_shrunk);
ExPolygons from_border_b = diff_ex(b, total_shrunk);
ExPolygons temp_a, temp_b;
for (coord_t i = 0; i < (detect / min_line) + 2; ++i) {
temp_a = offset_ex(from_border_a, min_line);
temp_b = offset_ex(from_border_b, min_line);
from_border_a = diff_ex(temp_a, temp_b);
from_border_b = diff_ex(temp_b, temp_a);
}
return {from_border_a, from_border_b};
}
void InterlockingGenerator::handleThinAreas(const std::unordered_set<GridPoint3>& has_all_meshes) const
{
const coord_t number_of_beams_detect = boundary_avoidance;
const coord_t number_of_beams_expand = boundary_avoidance - 1;
constexpr coord_t rounding_errors = 5;
const coord_t max_beam_width = beam_width;
const coord_t detect = (max_beam_width * number_of_beams_detect) + rounding_errors;
const coord_t expand = (max_beam_width * number_of_beams_expand) + rounding_errors;
const coord_t close_gaps =
std::min(print_object.printing_region(region_a_index).flow(print_object, frExternalPerimeter, 0.1).scaled_width(),
print_object.printing_region(region_b_index).flow(print_object, frExternalPerimeter, 0.1).scaled_width()) / 4;
// Make an inclusionary polygon, to only actually handle thin areas near actual microstructures (so not in skin for example).
std::vector<Polygons> near_interlock_per_layer;
near_interlock_per_layer.assign(print_object.layer_count(), Polygons());
for (const auto& cell : has_all_meshes) {
const auto bottom_corner = vu.toLowerCorner(cell);
for (coord_t layer_nr = bottom_corner.z();
layer_nr < bottom_corner.z() + cell_size.z() && layer_nr < static_cast<coord_t>(near_interlock_per_layer.size()); ++layer_nr) {
near_interlock_per_layer[static_cast<size_t>(layer_nr)].push_back(vu.toPolygon(cell));
}
}
for (auto& near_interlock : near_interlock_per_layer) {
near_interlock = offset(union_(closing(near_interlock, rounding_errors)), detect);
polygons_rotate(near_interlock, rotation);
}
// Only alter layers when they are present in both meshes, zip should take care if that.
for (size_t layer_nr = 0; layer_nr < print_object.layer_count(); layer_nr++){
auto layer = print_object.get_layer(layer_nr);
ExPolygons polys_a = to_expolygons(layer->get_region(region_a_index)->slices.surfaces);
ExPolygons polys_b = to_expolygons(layer->get_region(region_b_index)->slices.surfaces);
const auto [from_border_a, from_border_b] = growBorderAreasPerpendicular(polys_a, polys_b, detect);
// Get the areas of each mesh that are _not_ thin (large), by performing a morphological open.
const ExPolygons large_a = opening_ex(polys_a, detect);
const ExPolygons large_b = opening_ex(polys_b, detect);
// Derive the area that the thin areas need to expand into (so the added areas to the thin strips) from the information we already have.
const ExPolygons thin_expansion_a =
offset_ex(intersection_ex(intersection_ex(intersection_ex(large_b, offset_ex(diff_ex(polys_a, large_a), expand)),
near_interlock_per_layer[layer_nr]),
from_border_a),
rounding_errors);
const ExPolygons thin_expansion_b =
offset_ex(intersection_ex(intersection_ex(intersection_ex(large_a, offset_ex(diff_ex(polys_b, large_b), expand)),
near_interlock_per_layer[layer_nr]),
from_border_b),
rounding_errors);
// Expanded thin areas of the opposing polygon should 'eat into' the larger areas of the polygon,
// and conversely, add the expansions to their own thin areas.
layer->get_region(region_a_index)->slices.set(closing_ex(diff_ex(union_ex(polys_a, thin_expansion_a), thin_expansion_b), close_gaps), stInternal);
layer->get_region(region_b_index)->slices.set(closing_ex(diff_ex(union_ex(polys_b, thin_expansion_b), thin_expansion_a), close_gaps), stInternal);
}
}
void InterlockingGenerator::generateInterlockingStructure() const
{
std::vector<std::unordered_set<GridPoint3>> voxels_per_mesh = getShellVoxels(interface_dilation);
std::unordered_set<GridPoint3>& has_any_mesh = voxels_per_mesh[0];
std::unordered_set<GridPoint3>& has_all_meshes = voxels_per_mesh[1];
has_any_mesh.merge(has_all_meshes); // perform union and intersection simultaneously. Cannibalizes voxels_per_mesh
if (has_all_meshes.empty()) {
return;
}
const std::vector<ExPolygons> layer_regions = computeUnionedVolumeRegions();
if (air_filtering) {
std::unordered_set<GridPoint3> air_cells;
addBoundaryCells(layer_regions, air_dilation, air_cells);
for (const GridPoint3& p : air_cells) {
has_all_meshes.erase(p);
}
handleThinAreas(has_all_meshes);
}
applyMicrostructureToOutlines(has_all_meshes, layer_regions);
}
std::vector<std::unordered_set<GridPoint3>> InterlockingGenerator::getShellVoxels(const DilationKernel& kernel) const
{
std::vector<std::unordered_set<GridPoint3>> voxels_per_mesh(2);
// mark all cells which contain some boundary
for (size_t region_idx = 0; region_idx < 2; region_idx++)
{
const size_t region = (region_idx == 0) ? region_a_index : region_b_index;
std::unordered_set<GridPoint3>& mesh_voxels = voxels_per_mesh[region_idx];
std::vector<ExPolygons> rotated_polygons_per_layer(print_object.layer_count());
for (size_t layer_nr = 0; layer_nr < print_object.layer_count(); layer_nr++)
{
auto layer = print_object.get_layer(layer_nr);
rotated_polygons_per_layer[layer_nr] = to_expolygons(layer->get_region(region)->slices.surfaces);
expolygons_rotate(rotated_polygons_per_layer[layer_nr], rotation);
}
addBoundaryCells(rotated_polygons_per_layer, kernel, mesh_voxels);
}
return voxels_per_mesh;
}
void InterlockingGenerator::addBoundaryCells(const std::vector<ExPolygons>& layers,
const DilationKernel& kernel,
std::unordered_set<GridPoint3>& cells) const
{
auto voxel_emplacer = [&cells](GridPoint3 p) {
if (p.z() < 0) {
return true;
}
cells.emplace(p);
return true;
};
for (size_t layer_nr = 0; layer_nr < layers.size(); layer_nr++) {
const coord_t z = static_cast<coord_t>(layer_nr);
vu.walkDilatedPolygons(layers[layer_nr], z, kernel, voxel_emplacer);
ExPolygons skin = layers[layer_nr];
if (layer_nr > 0) {
skin = xor_ex(skin, layers[layer_nr - 1]);
}
skin = opening_ex(skin, cell_size.x() / 2.f); // remove superfluous small areas, which would anyway be included because of walkPolygons
vu.walkDilatedAreas(skin, z, kernel, voxel_emplacer);
}
}
std::vector<ExPolygons> InterlockingGenerator::computeUnionedVolumeRegions() const
{
const size_t max_layer_count = print_object.layer_count() +
1; // introduce ghost layer on top for correct skin computation of topmost layer.
std::vector<ExPolygons> layer_regions(max_layer_count);
for (size_t layer_nr = 0; layer_nr < max_layer_count - 1; layer_nr++) {
auto& layer_region = layer_regions[static_cast<size_t>(layer_nr)];
for (size_t region_idx : {region_a_index, region_b_index}) {
auto layer = print_object.get_layer(layer_nr);
expolygons_append(layer_region, to_expolygons(layer->get_region(region_idx)->slices.surfaces));
}
layer_region = closing_ex(layer_region, ignored_gap_); // Morphological close to merge meshes into single volume
expolygons_rotate(layer_region, rotation);
}
return layer_regions;
}
std::vector<std::vector<ExPolygons>> InterlockingGenerator::generateMicrostructure() const
{
std::vector<std::vector<ExPolygons>> cell_area_per_mesh_per_layer;
cell_area_per_mesh_per_layer.resize(2);
cell_area_per_mesh_per_layer[0].resize(2);
//const coord_t beam_w_sum = beam_width + beam_width;
//const coord_t middle = cell_size.x() * beam_width / beam_w_sum;
const coord_t middle = cell_size.x() / 2;
const coord_t width[2] = {middle, cell_size.x() - middle};
for (size_t mesh_idx : {0ul, 1ul}) {
Point offset(mesh_idx ? middle : 0, 0);
Point area_size(width[mesh_idx], cell_size.y());
Polygon poly;
poly.append(offset);
poly.append(offset + Point(area_size.x(), 0));
poly.append(offset + area_size);
poly.append(offset + Point(0, area_size.y()));
cell_area_per_mesh_per_layer[0][mesh_idx].emplace_back(poly);
}
cell_area_per_mesh_per_layer[1] = cell_area_per_mesh_per_layer[0];
for (ExPolygons& polys : cell_area_per_mesh_per_layer[1]) {
for (ExPolygon& poly : polys) {
for (Point& p : poly.contour) {
std::swap(p.x(), p.y());
}
}
}
return cell_area_per_mesh_per_layer;
}
void InterlockingGenerator::applyMicrostructureToOutlines(const std::unordered_set<GridPoint3>& cells,
const std::vector<ExPolygons>& layer_regions) const
{
std::vector<std::vector<ExPolygons>> cell_area_per_mesh_per_layer = generateMicrostructure();
const float unapply_rotation = -rotation;
const size_t max_layer_count = print_object.layer_count();
std::vector<ExPolygons> structure_per_layer[2]; // for each mesh the structure on each layer
// Every `beam_layer_count` number of layers are combined to an interlocking beam layer
// to store these we need ceil(max_layer_count / beam_layer_count) of these layers
// the formula is rewritten as (max_layer_count + beam_layer_count - 1) / beam_layer_count, so it works for integer division
size_t num_interlocking_layers = (max_layer_count + static_cast<size_t>(beam_layer_count) - 1ul) /
static_cast<size_t>(beam_layer_count);
structure_per_layer[0].resize(num_interlocking_layers);
structure_per_layer[1].resize(num_interlocking_layers);
// Only compute cell structure for half the layers, because since our beams are two layers high, every odd layer of the structure will
// be the same as the layer below.
for (const GridPoint3& grid_loc : cells) {
Vec3crd bottom_corner = vu.toLowerCorner(grid_loc);
for (size_t mesh_idx = 0; mesh_idx < 2; mesh_idx++) {
for (size_t layer_nr = bottom_corner.z(); layer_nr < bottom_corner.z() + cell_size.z() && layer_nr < max_layer_count;
layer_nr += beam_layer_count) {
ExPolygons areas_here = cell_area_per_mesh_per_layer[static_cast<size_t>(layer_nr / beam_layer_count) %
cell_area_per_mesh_per_layer.size()][mesh_idx];
for (auto & here : areas_here) {
here.translate(bottom_corner.x(), bottom_corner.y());
}
expolygons_append(structure_per_layer[mesh_idx][static_cast<size_t>(layer_nr / beam_layer_count)], areas_here);
}
}
}
for (size_t mesh_idx = 0; mesh_idx < 2; mesh_idx++) {
for (size_t layer_nr = 0; layer_nr < structure_per_layer[mesh_idx].size(); layer_nr++) {
ExPolygons& layer_structure = structure_per_layer[mesh_idx][layer_nr];
layer_structure = union_ex(layer_structure);
expolygons_rotate(layer_structure, unapply_rotation);
}
}
for (size_t region_idx = 0; region_idx < 2; region_idx++) {
const size_t region = (region_idx == 0) ? region_a_index : region_b_index;
for (size_t layer_nr = 0; layer_nr < max_layer_count; layer_nr++) {
ExPolygons layer_outlines = layer_regions[layer_nr];
expolygons_rotate(layer_outlines, unapply_rotation);
const ExPolygons areas_here = intersection_ex(structure_per_layer[region_idx][layer_nr / static_cast<size_t>(beam_layer_count)], layer_outlines);
const ExPolygons& areas_other = structure_per_layer[!region_idx][layer_nr / static_cast<size_t>(beam_layer_count)];
auto layer = print_object.get_layer(layer_nr);
auto& slices = layer->get_region(region)->slices;
ExPolygons polys = to_expolygons(slices.surfaces);
slices.set(union_ex(diff_ex(polys, areas_other), // reduce layer areas inward with beams from other mesh
areas_here) // extend layer areas outward with newly added beams
, stInternal);
}
}
}
} // namespace Slic3r