BambuStudio/libslic3r/CSGMesh/SliceCSGMesh.hpp

132 lines
4.3 KiB
C++

#ifndef SLICECSGMESH_HPP
#define SLICECSGMESH_HPP
#include "CSGMesh.hpp"
#include <stack>
#include "libslic3r/TriangleMeshSlicer.hpp"
#include "libslic3r/ClipperUtils.hpp"
#include "libslic3r/Execution/ExecutionTBB.hpp"
namespace Slic3r { namespace csg {
namespace detail {
inline void merge_slices(csg::CSGType op, size_t i,
std::vector<ExPolygons> &target,
std::vector<ExPolygons> &source)
{
switch(op) {
case CSGType::Union:
for (ExPolygon &expoly : source[i])
target[i].emplace_back(std::move(expoly));
break;
case CSGType::Difference:
target[i] = diff_ex(target[i], source[i]);
break;
case CSGType::Intersection:
target[i] = intersection_ex(target[i], source[i]);
break;
}
}
inline void collect_nonempty_indices(csg::CSGType op,
const std::vector<float> &slicegrid,
const std::vector<ExPolygons> &slices,
std::vector<size_t> &indices)
{
indices.clear();
for (size_t i = 0; i < slicegrid.size(); ++i) {
if (op == CSGType::Intersection || !slices[i].empty())
indices.emplace_back(i);
}
}
} // namespace detail
template<class ItCSG>
std::vector<ExPolygons> slice_csgmesh_ex(
const Range<ItCSG> &csgrange,
const std::vector<float> &slicegrid,
const MeshSlicingParamsEx &params,
const std::function<void()> &throw_on_cancel = [] {})
{
using namespace detail;
struct Frame { CSGType op; std::vector<ExPolygons> slices; };
std::stack opstack{std::vector<Frame>{}};
MeshSlicingParamsEx params_cpy = params;
auto trafo = params.trafo;
auto nonempty_indices = reserve_vector<size_t>(slicegrid.size());
opstack.push({CSGType::Union, std::vector<ExPolygons>(slicegrid.size())});
for (const auto &csgpart : csgrange) {
const indexed_triangle_set *its = csg::get_mesh(csgpart);
auto op = get_operation(csgpart);
if (get_stack_operation(csgpart) == CSGStackOp::Push) {
opstack.push({op, std::vector<ExPolygons>(slicegrid.size())});
op = CSGType::Union;
}
Frame *top = &opstack.top();
if (its) {
params_cpy.trafo = trafo * csg::get_transform(csgpart).template cast<double>();
std::vector<ExPolygons> slices = slice_mesh_ex(*its,
slicegrid, params_cpy,
throw_on_cancel);
assert(slices.size() == slicegrid.size());
collect_nonempty_indices(op, slicegrid, slices, nonempty_indices);
execution::for_each(
ex_tbb, nonempty_indices.begin(), nonempty_indices.end(),
[op, &slices, &top](size_t i) {
merge_slices(op, i, top->slices, slices);
}, execution::max_concurrency(ex_tbb));
}
if (get_stack_operation(csgpart) == CSGStackOp::Pop) {
std::vector<ExPolygons> popslices = std::move(top->slices);
auto popop = opstack.top().op;
opstack.pop();
std::vector<ExPolygons> &prev_slices = opstack.top().slices;
collect_nonempty_indices(popop, slicegrid, popslices, nonempty_indices);
execution::for_each(
ex_tbb, nonempty_indices.begin(), nonempty_indices.end(),
[&popslices, &prev_slices, popop](size_t i) {
merge_slices(popop, i, prev_slices, popslices);
}, execution::max_concurrency(ex_tbb));
}
}
std::vector<ExPolygons> ret = std::move(opstack.top().slices);
// TODO: verify if this part can be omitted or not.
execution::for_each(ex_tbb, ret.begin(), ret.end(), [](ExPolygons &slice) {
auto it = std::remove_if(slice.begin(), slice.end(), [](const ExPolygon &p){
return p.area() < double(SCALED_EPSILON) * double(SCALED_EPSILON);
});
// Hopefully, ExPolygons are moved, not copied to new positions
// and that is cheap for expolygons
slice.erase(it, slice.end());
slice = union_ex(slice);
}, execution::max_concurrency(ex_tbb));
return ret;
}
}} // namespace Slic3r::csg
#endif // SLICECSGMESH_HPP