3DPrinting/PrusaSlicer-NonPlainar
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Eradicated admesh from TriangleMesh:

Browse source 
TriangleMesh newly only holds indexed_triangle_set and
TriangleMeshStats. TriangleMeshStats contains an excerpt of stl_stats.
TriangleMeshStats are updated when initializing with indexed_triangle_set.

Admesh triangle mesh fixing is newly only used when loading an STL.
AMF / 3MF / OBJ file formats are already indexed triangle sets, thus
they are no more converted to admesh stl_file format, nor fixed
through admesh repair machinery. When importing AMF / 3MF / OBJ files,
volume is calculated and if negative, all faces are flipped. Also
a bounding box and number of open edges is calculated.

Implemented its_number_of_patches(), its_num_open_edges()
Optimized its_split(), its_is_splittable() using a visitor pattern.

Reworked QHull integration into TriangleMesh:
    1) Face normals were not right.
    2) Indexed triangle set is newly emitted instead of duplicating
       vertices for each face.

Fixed cut_mesh(): Orient the triangulated faces correctly.
This commit is contained in:
Vojtech Bubnik 2021-09-20 17:12:22 +02:00
parent f484953a5a
commit 8a2a9dba2f
59 changed files with 1056 additions and 1758 deletions
src/libslic3r
MeshSplitImpl.hpp

155
src/libslic3r/MeshSplitImpl.hpp
View file

@ -28,65 +28,84 @@ template<> struct ItsWithNeighborsIndex_<indexed_triangle_set> {
}
};
// Visit all unvisited neighboring facets that are reachable from the first unvisited facet,
// and return them.
// Discover connected patches of facets one by one.
template<class NeighborIndex>
std::vector<size_t> its_find_unvisited_neighbors(
const indexed_triangle_set &its,
const NeighborIndex & neighbor_index,
std::vector<char> & visited)
{
using stack_el = size_t;
auto facestack = reserve_vector<stack_el>(its.indices.size());
auto push = [&facestack] (const stack_el &s) { facestack.emplace_back(s); };
auto pop = [&facestack] () -> stack_el {
stack_el ret = facestack.back();
facestack.pop_back();
return ret;
};
// find the next unvisited facet and push the index
auto facet = std::find(visited.begin(), visited.end(), false);
std::vector<size_t> ret;
if (facet != visited.end()) {
ret.reserve(its.indices.size());
auto idx = size_t(facet - visited.begin());
push(idx);
ret.emplace_back(idx);
visited[idx] = true;
struct NeighborVisitor {
NeighborVisitor(const indexed_triangle_set &its, const NeighborIndex &neighbor_index) :
its(its), neighbor_index(neighbor_index) {
m_visited.assign(its.indices.size(), false);
m_facestack.reserve(its.indices.size());
}
NeighborVisitor(const indexed_triangle_set &its, NeighborIndex &&aneighbor_index) :
its(its), neighbor_index(m_neighbor_index_data), m_neighbor_index_data(std::move(aneighbor_index)) {
m_visited.assign(its.indices.size(), false);
m_facestack.reserve(its.indices.size());
}
while (!facestack.empty()) {
size_t facet_idx = pop();
const auto &neighbors = neighbor_index[facet_idx];
for (auto neighbor_idx : neighbors) {
if (size_t(neighbor_idx) < visited.size() && !visited[size_t(neighbor_idx)]) {
visited[size_t(neighbor_idx)] = true;
push(stack_el(neighbor_idx));
ret.emplace_back(size_t(neighbor_idx));
template<typename Visitor>
void visit(Visitor visitor)
{
// find the next unvisited facet and push the index
auto facet = std::find(m_visited.begin() + m_seed, m_visited.end(), false);
m_seed = facet - m_visited.begin();
if (facet != m_visited.end()) {
// Skip this element in the next round.
auto idx = m_seed ++;
if (! visitor(idx))
return;
this->push(idx);
m_visited[idx] = true;
while (! m_facestack.empty()) {
size_t facet_idx = this->pop();
for (auto neighbor_idx : neighbor_index[facet_idx]) {
assert(neighbor_idx < int(m_visited.size()));
if (neighbor_idx >= 0 && !m_visited[neighbor_idx]) {
if (! visitor(size_t(neighbor_idx)))
return;
m_visited[neighbor_idx] = true;
this->push(stack_el(neighbor_idx));
}
}
}
}
}
return ret;
}
const indexed_triangle_set &its;
const NeighborIndex &neighbor_index;
private:
// If initialized with &&neighbor_index, take the ownership of the data.
const NeighborIndex m_neighbor_index_data;
std::vector<char> m_visited;
using stack_el = size_t;
std::vector<stack_el> m_facestack;
void push(const stack_el &s) { m_facestack.emplace_back(s); }
stack_el pop() { stack_el ret = m_facestack.back(); m_facestack.pop_back(); return ret; }
// Last face visited.
size_t m_seed { 0 };
};
} // namespace meshsplit_detail
// Funky wrapper for timinig of its_split() using various neighbor index creating methods, see sandboxes/its_neighbor_index/main.cpp
template<class IndexT> struct ItsNeighborsWrapper
{
using Index = IndexT;
const indexed_triangle_set *its;
IndexT index;
const indexed_triangle_set &its;
const IndexT &index_ref;
const IndexT index;
ItsNeighborsWrapper(const indexed_triangle_set &m, IndexT &&idx)
: its{&m}, index{std::move(idx)}
{}
// Keeping a reference to index, the caller is responsible for keeping the index alive.
ItsNeighborsWrapper(const indexed_triangle_set &its, const IndexT &index) : its{its}, index_ref{index} {}
// Taking ownership of the index.
ItsNeighborsWrapper(const indexed_triangle_set &its, IndexT &&aindex) : its{its}, index_ref{index}, index(std::move(aindex)) {}
const auto& get_its() const noexcept { return *its; }
const auto& get_index() const noexcept { return index; }
const auto& get_its() const noexcept { return its; }
const auto& get_index() const noexcept { return index_ref; }
};
// Splits a mesh into multiple meshes when possible.
@ -97,20 +116,19 @@ void its_split(const Its &m, OutputIt out_it)
const indexed_triangle_set &its = ItsWithNeighborsIndex_<Its>::get_its(m);
std::vector<char> visited(its.indices.size(), false);
struct VertexConv {
size_t part_id = std::numeric_limits<size_t>::max();
size_t vertex_image;
};
std::vector<VertexConv> vidx_conv(its.vertices.size());
const auto& neighbor_index = ItsWithNeighborsIndex_<Its>::get_index(m);
meshsplit_detail::NeighborVisitor visitor(its, meshsplit_detail::ItsWithNeighborsIndex_<Its>::get_index(m));
std::vector<size_t> facets;
for (size_t part_id = 0;; ++part_id) {
std::vector<size_t> facets =
its_find_unvisited_neighbors(its, neighbor_index, visited);
// Collect all faces of the next patch.
facets.clear();
visitor.visit([&facets](size_t idx) { facets.emplace_back(idx); return true; });
if (facets.empty())
break;
@ -150,17 +168,34 @@ std::vector<indexed_triangle_set> its_split(const Its &its)
return ret;
}
template<class Its> bool its_is_splittable(const Its &m)
template<class Its>
bool its_is_splittable(const Its &m)
{
using namespace meshsplit_detail;
const indexed_triangle_set &its = ItsWithNeighborsIndex_<Its>::get_its(m);
const auto& neighbor_index = ItsWithNeighborsIndex_<Its>::get_index(m);
meshsplit_detail::NeighborVisitor visitor(meshsplit_detail::ItsWithNeighborsIndex_<Its>::get_its(m), meshsplit_detail::ItsWithNeighborsIndex_<Its>::get_index(m));
bool has_some = false;
bool has_some2 = false;
// Traverse the 1st patch fully.
visitor.visit([&has_some](size_t idx) { has_some = true; return true; });
if (has_some)
// Just check whether there is any face of the 2nd patch.
visitor.visit([&has_some2](size_t idx) { has_some2 = true; return false; });
return has_some && has_some2;
}
std::vector<char> visited(its.indices.size(), false);
its_find_unvisited_neighbors(its, neighbor_index, visited);
auto faces = its_find_unvisited_neighbors(its, neighbor_index, visited);
return !faces.empty();
template<class Its>
size_t its_number_of_patches(const Its &m)
{
meshsplit_detail::NeighborVisitor visitor(meshsplit_detail::ItsWithNeighborsIndex_<Its>::get_its(m), meshsplit_detail::ItsWithNeighborsIndex_<Its>::get_index(m));
size_t num_patches = 0;
for (;;) {
bool has_some = false;
// Traverse the 1st patch fully.
visitor.visit([&has_some](size_t idx) { has_some = true; return true; });
if (! has_some)
break;
++ num_patches;
}
return num_patches;
}
template<class ExPolicy>