1364 lines
63 KiB
C++
1364 lines
63 KiB
C++
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#include "ClipperUtils.hpp"
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#include "Geometry.hpp"
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#include "Tesselate.hpp"
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#include "TriangleMesh.hpp"
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#include "TriangleMeshSlicer.hpp"
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#include <algorithm>
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#include <cmath>
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#include <deque>
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#include <queue>
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#include <utility>
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#include <boost/log/trivial.hpp>
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#include <tbb/parallel_for.h>
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#if 0
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#define DEBUG
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#define _DEBUG
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#undef NDEBUG
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#define SLIC3R_DEBUG
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// #define SLIC3R_TRIANGLEMESH_DEBUG
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#endif
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#include <assert.h>
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#if defined(SLIC3R_DEBUG) || defined(SLIC3R_DEBUG_SLICE_PROCESSING)
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#include "SVG.hpp"
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#endif
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namespace Slic3r {
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class IntersectionReference
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{
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public:
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IntersectionReference() = default;
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IntersectionReference(int point_id, int edge_id) : point_id(point_id), edge_id(edge_id) {}
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// Where is this intersection point located? On mesh vertex or mesh edge?
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// Only one of the following will be set, the other will remain set to -1.
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// Index of the mesh vertex.
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int point_id { -1 };
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// Index of the mesh edge.
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int edge_id { -1 };
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};
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class IntersectionPoint : public Point, public IntersectionReference
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{
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public:
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IntersectionPoint() = default;
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IntersectionPoint(int point_id, int edge_id, const Point &pt) : IntersectionReference(point_id, edge_id), Point(pt) {}
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IntersectionPoint(const IntersectionReference &ir, const Point &pt) : IntersectionReference(ir), Point(pt) {}
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// Inherits coord_t x, y
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};
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class IntersectionLine : public Line
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{
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public:
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IntersectionLine() = default;
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bool skip() const { return (this->flags & SKIP) != 0; }
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void set_skip() { this->flags |= SKIP; }
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bool is_seed_candidate() const { return (this->flags & NO_SEED) == 0 && ! this->skip(); }
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void set_no_seed(bool set) { if (set) this->flags |= NO_SEED; else this->flags &= ~NO_SEED; }
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// Inherits Point a, b
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// For each line end point, either {a,b}_id or {a,b}edge_a_id is set, the other is left to -1.
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// Vertex indices of the line end points.
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int a_id { -1 };
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int b_id { -1 };
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// Source mesh edges of the line end points.
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int edge_a_id { -1 };
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int edge_b_id { -1 };
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enum class FacetEdgeType {
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// A general case, the cutting plane intersect a face at two different edges.
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General,
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// Two vertices are aligned with the cutting plane, the third vertex is below the cutting plane.
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Top,
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// Two vertices are aligned with the cutting plane, the third vertex is above the cutting plane.
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Bottom,
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// All three vertices of a face are aligned with the cutting plane.
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Horizontal
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};
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// feGeneral, feTop, feBottom, feHorizontal
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FacetEdgeType edge_type { FacetEdgeType::General };
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// Used by TriangleMeshSlicer::slice() to skip duplicate edges.
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enum {
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// Triangle edge added, because it has no neighbor.
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EDGE0_NO_NEIGHBOR = 0x001,
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EDGE1_NO_NEIGHBOR = 0x002,
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EDGE2_NO_NEIGHBOR = 0x004,
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// Triangle edge added, because it makes a fold with another horizontal edge.
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EDGE0_FOLD = 0x010,
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EDGE1_FOLD = 0x020,
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EDGE2_FOLD = 0x040,
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// The edge cannot be a seed of a greedy loop extraction (folds are not safe to become seeds).
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NO_SEED = 0x100,
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SKIP = 0x200,
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};
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uint32_t flags { 0 };
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};
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using IntersectionLines = std::vector<IntersectionLine>;
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enum class FacetSliceType {
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NoSlice = 0,
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Slicing = 1,
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Cutting = 2
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};
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// Return true, if the facet has been sliced and line_out has been filled.
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static FacetSliceType slice_facet(
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float slice_z, const stl_vertex *vertices, const stl_triangle_vertex_indices &indices, const int *edge_neighbor,
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const int idx_vertex_lowest, const bool horizontal, IntersectionLine *line_out)
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{
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IntersectionPoint points[3];
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size_t num_points = 0;
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auto point_on_layer = size_t(-1);
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// Reorder vertices so that the first one is the one with lowest Z.
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// This is needed to get all intersection lines in a consistent order
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// (external on the right of the line)
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for (int j = 0; j < 3; ++ j) { // loop through facet edges
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int edge_id;
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const stl_vertex *a, *b;
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int a_id, b_id;
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{
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int k = (idx_vertex_lowest + j) % 3;
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int l = (k + 1) % 3;
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edge_id = edge_neighbor[k];
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a_id = indices[k];
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a = vertices + k;
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b_id = indices[l];
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b = vertices + l;
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}
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// Is edge or face aligned with the cutting plane?
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if (a->z() == slice_z && b->z() == slice_z) {
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// Edge is horizontal and belongs to the current layer.
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// The following rotation of the three vertices may not be efficient, but this branch happens rarely.
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const stl_vertex &v0 = vertices[0];
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const stl_vertex &v1 = vertices[1];
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const stl_vertex &v2 = vertices[2];
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// We may ignore this edge for slicing purposes, but we may still use it for object cutting.
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FacetSliceType result = FacetSliceType::Slicing;
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if (horizontal) {
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// All three vertices are aligned with slice_z.
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line_out->edge_type = IntersectionLine::FacetEdgeType::Horizontal;
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result = FacetSliceType::Cutting;
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double normal = (v1.x() - v0.x()) * (v2.y() - v1.y()) - (v1.y() - v0.y()) * (v2.x() - v1.x());
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if (normal < 0) {
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// If normal points downwards this is a bottom horizontal facet so we reverse its point order.
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std::swap(a, b);
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std::swap(a_id, b_id);
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}
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} else {
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// Two vertices are aligned with the cutting plane, the third vertex is below or above the cutting plane.
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// Is the third vertex below the cutting plane?
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bool third_below = v0.z() < slice_z || v1.z() < slice_z || v2.z() < slice_z;
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// Two vertices on the cutting plane, the third vertex is below the plane. Consider the edge to be part of the slice
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// only if it is the upper edge.
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// (the bottom most edge resp. vertex of a triangle is not owned by the triangle, but the top most edge resp. vertex is part of the triangle
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// in respect to the cutting plane).
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result = third_below ? FacetSliceType::Slicing : FacetSliceType::Cutting;
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if (third_below) {
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line_out->edge_type = IntersectionLine::FacetEdgeType::Top;
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std::swap(a, b);
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std::swap(a_id, b_id);
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} else
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line_out->edge_type = IntersectionLine::FacetEdgeType::Bottom;
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}
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line_out->a.x() = a->x();
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line_out->a.y() = a->y();
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line_out->b.x() = b->x();
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line_out->b.y() = b->y();
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line_out->a_id = a_id;
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line_out->b_id = b_id;
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assert(line_out->a != line_out->b);
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return result;
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}
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if (a->z() == slice_z) {
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// Only point a alings with the cutting plane.
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if (point_on_layer == size_t(-1) || points[point_on_layer].point_id != a_id) {
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point_on_layer = num_points;
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IntersectionPoint &point = points[num_points ++];
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point.x() = a->x();
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point.y() = a->y();
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point.point_id = a_id;
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}
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} else if (b->z() == slice_z) {
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// Only point b alings with the cutting plane.
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if (point_on_layer == size_t(-1) || points[point_on_layer].point_id != b_id) {
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point_on_layer = num_points;
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IntersectionPoint &point = points[num_points ++];
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point.x() = b->x();
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point.y() = b->y();
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point.point_id = b_id;
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}
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} else if ((a->z() < slice_z && b->z() > slice_z) || (b->z() < slice_z && a->z() > slice_z)) {
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// A general case. The face edge intersects the cutting plane. Calculate the intersection point.
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assert(a_id != b_id);
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// Sort the edge to give a consistent answer.
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if (a_id > b_id) {
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std::swap(a_id, b_id);
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std::swap(a, b);
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}
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IntersectionPoint &point = points[num_points];
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double t = (double(slice_z) - double(b->z())) / (double(a->z()) - double(b->z()));
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if (t <= 0.) {
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if (point_on_layer == size_t(-1) || points[point_on_layer].point_id != a_id) {
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point.x() = a->x();
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point.y() = a->y();
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point_on_layer = num_points ++;
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point.point_id = a_id;
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}
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} else if (t >= 1.) {
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if (point_on_layer == size_t(-1) || points[point_on_layer].point_id != b_id) {
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point.x() = b->x();
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point.y() = b->y();
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point_on_layer = num_points ++;
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point.point_id = b_id;
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}
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} else {
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point.x() = coord_t(floor(double(b->x()) + (double(a->x()) - double(b->x())) * t + 0.5));
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point.y() = coord_t(floor(double(b->y()) + (double(a->y()) - double(b->y())) * t + 0.5));
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point.edge_id = edge_id;
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++ num_points;
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}
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}
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}
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// Facets must intersect each plane 0 or 2 times, or it may touch the plane at a single vertex only.
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assert(num_points < 3);
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if (num_points == 2) {
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line_out->edge_type = IntersectionLine::FacetEdgeType::General;
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line_out->a = (Point)points[1];
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line_out->b = (Point)points[0];
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line_out->a_id = points[1].point_id;
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line_out->b_id = points[0].point_id;
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line_out->edge_a_id = points[1].edge_id;
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line_out->edge_b_id = points[0].edge_id;
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// Not a zero lenght edge.
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//FIXME slice_facet() may create zero length edges due to rounding of doubles into coord_t.
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//assert(line_out->a != line_out->b);
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// The plane cuts at least one edge in a general position.
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assert(line_out->a_id == -1 || line_out->b_id == -1);
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assert(line_out->edge_a_id != -1 || line_out->edge_b_id != -1);
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// General slicing position, use the segment for both slicing and object cutting.
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#if 0
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if (line_out->a_id != -1 && line_out->b_id != -1) {
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// Solving a degenerate case, where both the intersections snapped to an edge.
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// Correctly classify the face as below or above based on the position of the 3rd point.
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int i = indices[0];
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if (i == line_out->a_id || i == line_out->b_id)
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i = indices[1];
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if (i == line_out->a_id || i == line_out->b_id)
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i = indices[2];
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assert(i != line_out->a_id && i != line_out->b_id);
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line_out->edge_type = ((m_use_quaternion ?
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(m_quaternion * this->v_scaled_shared[i]).z()
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: this->v_scaled_shared[i].z()) < slice_z) ? IntersectionLine::FacetEdgeType::Top : IntersectionLine::FacetEdgeType::Bottom;
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}
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#endif
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return FacetSliceType::Slicing;
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}
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return FacetSliceType::NoSlice;
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}
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static void slice_facet_at_zs(
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const stl_triangle_vertex_indices &indices,
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const std::vector<Vec3f> &v_scaled_shared,
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const int *facet_neighbors,
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const Eigen::Quaternion<float, Eigen::DontAlign> *quaternion,
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std::vector<IntersectionLines> *lines,
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boost::mutex *lines_mutex,
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const std::vector<float> &scaled_zs)
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{
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stl_vertex vertices[3] { v_scaled_shared[indices(0)], v_scaled_shared[indices(1)], v_scaled_shared[indices(2)] };
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if (quaternion)
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for (int i = 0; i < 3; ++ i)
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vertices[i] = *quaternion * vertices[i];
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// find facet extents
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const float min_z = fminf(vertices[0].z(), fminf(vertices[1].z(), vertices[2].z()));
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const float max_z = fmaxf(vertices[0].z(), fmaxf(vertices[1].z(), vertices[2].z()));
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// find layer extents
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auto min_layer = std::lower_bound(scaled_zs.begin(), scaled_zs.end(), min_z); // first layer whose slice_z is >= min_z
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auto max_layer = std::upper_bound(min_layer, scaled_zs.end(), max_z); // first layer whose slice_z is > max_z
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for (auto it = min_layer; it != max_layer; ++ it) {
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IntersectionLine il;
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int idx_vertex_lowest = (vertices[1].z() == min_z) ? 1 : ((vertices[2].z() == min_z) ? 2 : 0);
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if (slice_facet(*it, vertices, indices, facet_neighbors, idx_vertex_lowest, min_z == max_z, &il) == FacetSliceType::Slicing &&
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il.edge_type != IntersectionLine::FacetEdgeType::Horizontal) {
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// Ignore horizontal triangles. Any valid horizontal triangle must have a vertical triangle connected, otherwise the part has zero volume.
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boost::lock_guard<boost::mutex> l(*lines_mutex);
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(*lines)[it - scaled_zs.begin()].emplace_back(il);
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}
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}
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}
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#if 0
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//FIXME Should this go away? For valid meshes the function slice_facet() returns Slicing
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// and sets edges of vertical triangles to produce only a single edge per pair of neighbor faces.
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// So the following code makes only sense now to handle degenerate meshes with more than two faces
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// sharing a single edge.
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static inline void remove_tangent_edges(std::vector<IntersectionLine> &lines)
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{
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std::vector<IntersectionLine*> by_vertex_pair;
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by_vertex_pair.reserve(lines.size());
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for (IntersectionLine& line : lines)
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if (line.edge_type != IntersectionLine::FacetEdgeType::General && line.a_id != -1)
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// This is a face edge. Check whether there is its neighbor stored in lines.
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by_vertex_pair.emplace_back(&line);
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auto edges_lower_sorted = [](const IntersectionLine *l1, const IntersectionLine *l2) {
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// Sort vertices of l1, l2 lexicographically
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||
|
|
int l1a = l1->a_id;
|
||
|
|
int l1b = l1->b_id;
|
||
|
|
int l2a = l2->a_id;
|
||
|
|
int l2b = l2->b_id;
|
||
|
|
if (l1a > l1b)
|
||
|
|
std::swap(l1a, l1b);
|
||
|
|
if (l2a > l2b)
|
||
|
|
std::swap(l2a, l2b);
|
||
|
|
// Lexicographical "lower" operator on lexicographically sorted vertices should bring equal edges together when sored.
|
||
|
|
return l1a < l2a || (l1a == l2a && l1b < l2b);
|
||
|
|
};
|
||
|
|
std::sort(by_vertex_pair.begin(), by_vertex_pair.end(), edges_lower_sorted);
|
||
|
|
for (auto line = by_vertex_pair.begin(); line != by_vertex_pair.end(); ++ line) {
|
||
|
|
IntersectionLine &l1 = **line;
|
||
|
|
if (! l1.skip()) {
|
||
|
|
// Iterate as long as line and line2 edges share the same end points.
|
||
|
|
for (auto line2 = line + 1; line2 != by_vertex_pair.end() && ! edges_lower_sorted(*line, *line2); ++ line2) {
|
||
|
|
// Lines must share the end points.
|
||
|
|
assert(! edges_lower_sorted(*line, *line2));
|
||
|
|
assert(! edges_lower_sorted(*line2, *line));
|
||
|
|
IntersectionLine &l2 = **line2;
|
||
|
|
if (l2.skip())
|
||
|
|
continue;
|
||
|
|
if (l1.a_id == l2.a_id) {
|
||
|
|
assert(l1.b_id == l2.b_id);
|
||
|
|
l2.set_skip();
|
||
|
|
// If they are both oriented upwards or downwards (like a 'V'),
|
||
|
|
// then we can remove both edges from this layer since it won't
|
||
|
|
// affect the sliced shape.
|
||
|
|
// If one of them is oriented upwards and the other is oriented
|
||
|
|
// downwards, let's only keep one of them (it doesn't matter which
|
||
|
|
// one since all 'top' lines were reversed at slicing).
|
||
|
|
if (l1.edge_type == l2.edge_type) {
|
||
|
|
l1.set_skip();
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
assert(l1.a_id == l2.b_id && l1.b_id == l2.a_id);
|
||
|
|
// If this edge joins two horizontal facets, remove both of them.
|
||
|
|
if (l1.edge_type == IntersectionLine::FacetEdgeType::Horizontal && l2.edge_type == IntersectionLine::FacetEdgeType::Horizontal) {
|
||
|
|
l1.set_skip();
|
||
|
|
l2.set_skip();
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
struct OpenPolyline {
|
||
|
|
OpenPolyline() = default;
|
||
|
|
OpenPolyline(const IntersectionReference &start, const IntersectionReference &end, Points &&points) :
|
||
|
|
start(start), end(end), points(std::move(points)), consumed(false) { this->length = Slic3r::length(this->points); }
|
||
|
|
void reverse() {
|
||
|
|
std::swap(start, end);
|
||
|
|
std::reverse(points.begin(), points.end());
|
||
|
|
}
|
||
|
|
IntersectionReference start;
|
||
|
|
IntersectionReference end;
|
||
|
|
Points points;
|
||
|
|
double length;
|
||
|
|
bool consumed;
|
||
|
|
};
|
||
|
|
|
||
|
|
// called by TriangleMeshSlicer::make_loops() to connect sliced triangles into closed loops and open polylines by the triangle connectivity.
|
||
|
|
// Only connects segments crossing triangles of the same orientation.
|
||
|
|
static void chain_lines_by_triangle_connectivity(std::vector<IntersectionLine> &lines, Polygons &loops, std::vector<OpenPolyline> &open_polylines)
|
||
|
|
{
|
||
|
|
// Build a map of lines by edge_a_id and a_id.
|
||
|
|
std::vector<IntersectionLine*> by_edge_a_id;
|
||
|
|
std::vector<IntersectionLine*> by_a_id;
|
||
|
|
by_edge_a_id.reserve(lines.size());
|
||
|
|
by_a_id.reserve(lines.size());
|
||
|
|
for (IntersectionLine &line : lines) {
|
||
|
|
if (! line.skip()) {
|
||
|
|
if (line.edge_a_id != -1)
|
||
|
|
by_edge_a_id.emplace_back(&line);
|
||
|
|
if (line.a_id != -1)
|
||
|
|
by_a_id.emplace_back(&line);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
auto by_edge_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->edge_a_id < il2->edge_a_id; };
|
||
|
|
auto by_vertex_lower = [](const IntersectionLine* il1, const IntersectionLine *il2) { return il1->a_id < il2->a_id; };
|
||
|
|
std::sort(by_edge_a_id.begin(), by_edge_a_id.end(), by_edge_lower);
|
||
|
|
std::sort(by_a_id.begin(), by_a_id.end(), by_vertex_lower);
|
||
|
|
// Chain the segments with a greedy algorithm, collect the loops and unclosed polylines.
|
||
|
|
IntersectionLines::iterator it_line_seed = lines.begin();
|
||
|
|
for (;;) {
|
||
|
|
// take first spare line and start a new loop
|
||
|
|
IntersectionLine *first_line = nullptr;
|
||
|
|
for (; it_line_seed != lines.end(); ++ it_line_seed)
|
||
|
|
if (it_line_seed->is_seed_candidate()) {
|
||
|
|
//if (! it_line_seed->skip()) {
|
||
|
|
first_line = &(*it_line_seed ++);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (first_line == nullptr)
|
||
|
|
break;
|
||
|
|
first_line->set_skip();
|
||
|
|
Points loop_pts;
|
||
|
|
loop_pts.emplace_back(first_line->a);
|
||
|
|
IntersectionLine *last_line = first_line;
|
||
|
|
|
||
|
|
/*
|
||
|
|
printf("first_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n",
|
||
|
|
first_line->edge_a_id, first_line->edge_b_id, first_line->a_id, first_line->b_id,
|
||
|
|
first_line->a.x, first_line->a.y, first_line->b.x, first_line->b.y);
|
||
|
|
*/
|
||
|
|
|
||
|
|
IntersectionLine key;
|
||
|
|
for (;;) {
|
||
|
|
// find a line starting where last one finishes
|
||
|
|
IntersectionLine* next_line = nullptr;
|
||
|
|
if (last_line->edge_b_id != -1) {
|
||
|
|
key.edge_a_id = last_line->edge_b_id;
|
||
|
|
auto it_begin = std::lower_bound(by_edge_a_id.begin(), by_edge_a_id.end(), &key, by_edge_lower);
|
||
|
|
if (it_begin != by_edge_a_id.end()) {
|
||
|
|
auto it_end = std::upper_bound(it_begin, by_edge_a_id.end(), &key, by_edge_lower);
|
||
|
|
for (auto it_line = it_begin; it_line != it_end; ++ it_line)
|
||
|
|
if (! (*it_line)->skip()) {
|
||
|
|
next_line = *it_line;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (next_line == nullptr && last_line->b_id != -1) {
|
||
|
|
key.a_id = last_line->b_id;
|
||
|
|
auto it_begin = std::lower_bound(by_a_id.begin(), by_a_id.end(), &key, by_vertex_lower);
|
||
|
|
if (it_begin != by_a_id.end()) {
|
||
|
|
auto it_end = std::upper_bound(it_begin, by_a_id.end(), &key, by_vertex_lower);
|
||
|
|
for (auto it_line = it_begin; it_line != it_end; ++ it_line)
|
||
|
|
if (! (*it_line)->skip()) {
|
||
|
|
next_line = *it_line;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (next_line == nullptr) {
|
||
|
|
// Check whether we closed this loop.
|
||
|
|
if ((first_line->edge_a_id != -1 && first_line->edge_a_id == last_line->edge_b_id) ||
|
||
|
|
(first_line->a_id != -1 && first_line->a_id == last_line->b_id)) {
|
||
|
|
// The current loop is complete. Add it to the output.
|
||
|
|
loops.emplace_back(std::move(loop_pts));
|
||
|
|
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
|
||
|
|
printf(" Discovered %s polygon of %d points\n", (p.is_counter_clockwise() ? "ccw" : "cw"), (int)p.points.size());
|
||
|
|
#endif
|
||
|
|
} else {
|
||
|
|
// This is an open polyline. Add it to the list of open polylines. These open polylines will processed later.
|
||
|
|
loop_pts.emplace_back(last_line->b);
|
||
|
|
open_polylines.emplace_back(OpenPolyline(
|
||
|
|
IntersectionReference(first_line->a_id, first_line->edge_a_id),
|
||
|
|
IntersectionReference(last_line->b_id, last_line->edge_b_id), std::move(loop_pts)));
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
printf("next_line edge_a_id = %d, edge_b_id = %d, a_id = %d, b_id = %d, a = %d,%d, b = %d,%d\n",
|
||
|
|
next_line->edge_a_id, next_line->edge_b_id, next_line->a_id, next_line->b_id,
|
||
|
|
next_line->a.x, next_line->a.y, next_line->b.x, next_line->b.y);
|
||
|
|
*/
|
||
|
|
loop_pts.emplace_back(next_line->a);
|
||
|
|
last_line = next_line;
|
||
|
|
next_line->set_skip();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
std::vector<OpenPolyline*> open_polylines_sorted(std::vector<OpenPolyline> &open_polylines, bool update_lengths)
|
||
|
|
{
|
||
|
|
std::vector<OpenPolyline*> out;
|
||
|
|
out.reserve(open_polylines.size());
|
||
|
|
for (OpenPolyline &opl : open_polylines)
|
||
|
|
if (! opl.consumed) {
|
||
|
|
if (update_lengths)
|
||
|
|
opl.length = Slic3r::length(opl.points);
|
||
|
|
out.emplace_back(&opl);
|
||
|
|
}
|
||
|
|
std::sort(out.begin(), out.end(), [](const OpenPolyline *lhs, const OpenPolyline *rhs){ return lhs->length > rhs->length; });
|
||
|
|
return out;
|
||
|
|
}
|
||
|
|
|
||
|
|
// called by TriangleMeshSlicer::make_loops() to connect remaining open polylines across shared triangle edges and vertices.
|
||
|
|
// Depending on "try_connect_reversed", it may or may not connect segments crossing triangles of opposite orientation.
|
||
|
|
static void chain_open_polylines_exact(std::vector<OpenPolyline> &open_polylines, Polygons &loops, bool try_connect_reversed)
|
||
|
|
{
|
||
|
|
// Store the end points of open_polylines into vectors sorted
|
||
|
|
struct OpenPolylineEnd {
|
||
|
|
OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {}
|
||
|
|
OpenPolyline *polyline;
|
||
|
|
// Is it the start or end point?
|
||
|
|
bool start;
|
||
|
|
const IntersectionReference& ipref() const { return start ? polyline->start : polyline->end; }
|
||
|
|
// Return a unique ID for the intersection point.
|
||
|
|
// Return a positive id for a point, or a negative id for an edge.
|
||
|
|
int id() const { const IntersectionReference &r = ipref(); return (r.point_id >= 0) ? r.point_id : - r.edge_id; }
|
||
|
|
bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; }
|
||
|
|
};
|
||
|
|
auto by_id_lower = [](const OpenPolylineEnd &ope1, const OpenPolylineEnd &ope2) { return ope1.id() < ope2.id(); };
|
||
|
|
std::vector<OpenPolylineEnd> by_id;
|
||
|
|
by_id.reserve(2 * open_polylines.size());
|
||
|
|
for (OpenPolyline &opl : open_polylines) {
|
||
|
|
if (opl.start.point_id != -1 || opl.start.edge_id != -1)
|
||
|
|
by_id.emplace_back(OpenPolylineEnd(&opl, true));
|
||
|
|
if (try_connect_reversed && (opl.end.point_id != -1 || opl.end.edge_id != -1))
|
||
|
|
by_id.emplace_back(OpenPolylineEnd(&opl, false));
|
||
|
|
}
|
||
|
|
std::sort(by_id.begin(), by_id.end(), by_id_lower);
|
||
|
|
// Find an iterator to by_id_lower for the particular end of OpenPolyline (by comparing the OpenPolyline pointer and the start attribute).
|
||
|
|
auto find_polyline_end = [&by_id, by_id_lower](const OpenPolylineEnd &end) -> std::vector<OpenPolylineEnd>::iterator {
|
||
|
|
for (auto it = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower);
|
||
|
|
it != by_id.end() && it->id() == end.id(); ++ it)
|
||
|
|
if (*it == end)
|
||
|
|
return it;
|
||
|
|
return by_id.end();
|
||
|
|
};
|
||
|
|
// Try to connect the loops.
|
||
|
|
std::vector<OpenPolyline*> sorted_by_length = open_polylines_sorted(open_polylines, false);
|
||
|
|
for (OpenPolyline *opl : sorted_by_length) {
|
||
|
|
if (opl->consumed)
|
||
|
|
continue;
|
||
|
|
opl->consumed = true;
|
||
|
|
OpenPolylineEnd end(opl, false);
|
||
|
|
for (;;) {
|
||
|
|
// find a line starting where last one finishes
|
||
|
|
auto it_next_start = std::lower_bound(by_id.begin(), by_id.end(), end, by_id_lower);
|
||
|
|
for (; it_next_start != by_id.end() && it_next_start->id() == end.id(); ++ it_next_start)
|
||
|
|
if (! it_next_start->polyline->consumed)
|
||
|
|
goto found;
|
||
|
|
// The current loop could not be closed. Unmark the segment.
|
||
|
|
opl->consumed = false;
|
||
|
|
break;
|
||
|
|
found:
|
||
|
|
// Attach this polyline to the end of the initial polyline.
|
||
|
|
if (it_next_start->start) {
|
||
|
|
auto it = it_next_start->polyline->points.begin();
|
||
|
|
std::copy(++ it, it_next_start->polyline->points.end(), back_inserter(opl->points));
|
||
|
|
} else {
|
||
|
|
auto it = it_next_start->polyline->points.rbegin();
|
||
|
|
std::copy(++ it, it_next_start->polyline->points.rend(), back_inserter(opl->points));
|
||
|
|
}
|
||
|
|
opl->length += it_next_start->polyline->length;
|
||
|
|
// Mark the next polyline as consumed.
|
||
|
|
it_next_start->polyline->points.clear();
|
||
|
|
it_next_start->polyline->length = 0.;
|
||
|
|
it_next_start->polyline->consumed = true;
|
||
|
|
if (try_connect_reversed) {
|
||
|
|
// Running in a mode, where the polylines may be connected by mixing their orientations.
|
||
|
|
// Update the end point lookup structure after the end point of the current polyline was extended.
|
||
|
|
auto it_end = find_polyline_end(end);
|
||
|
|
auto it_next_end = find_polyline_end(OpenPolylineEnd(it_next_start->polyline, !it_next_start->start));
|
||
|
|
// Swap the end points of the current and next polyline, but keep the polyline ptr and the start flag.
|
||
|
|
std::swap(opl->end, it_next_end->start ? it_next_end->polyline->start : it_next_end->polyline->end);
|
||
|
|
// Swap the positions of OpenPolylineEnd structures in the sorted array to match their respective end point positions.
|
||
|
|
std::swap(*it_end, *it_next_end);
|
||
|
|
}
|
||
|
|
// Check whether we closed this loop.
|
||
|
|
if ((opl->start.edge_id != -1 && opl->start.edge_id == opl->end.edge_id) ||
|
||
|
|
(opl->start.point_id != -1 && opl->start.point_id == opl->end.point_id)) {
|
||
|
|
// The current loop is complete. Add it to the output.
|
||
|
|
//assert(opl->points.front().point_id == opl->points.back().point_id);
|
||
|
|
//assert(opl->points.front().edge_id == opl->points.back().edge_id);
|
||
|
|
// Remove the duplicate last point.
|
||
|
|
opl->points.pop_back();
|
||
|
|
if (opl->points.size() >= 3) {
|
||
|
|
if (try_connect_reversed && area(opl->points) < 0)
|
||
|
|
// The closed polygon is patched from pieces with messed up orientation, therefore
|
||
|
|
// the orientation of the patched up polygon is not known.
|
||
|
|
// Orient the patched up polygons CCW. This heuristic may close some holes and cavities.
|
||
|
|
std::reverse(opl->points.begin(), opl->points.end());
|
||
|
|
loops.emplace_back(std::move(opl->points));
|
||
|
|
}
|
||
|
|
opl->points.clear();
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
// Continue with the current loop.
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// called by TriangleMeshSlicer::make_loops() to connect remaining open polylines across shared triangle edges and vertices,
|
||
|
|
// possibly closing small gaps.
|
||
|
|
// Depending on "try_connect_reversed", it may or may not connect segments crossing triangles of opposite orientation.
|
||
|
|
static void chain_open_polylines_close_gaps(std::vector<OpenPolyline> &open_polylines, Polygons &loops, double max_gap, bool try_connect_reversed)
|
||
|
|
{
|
||
|
|
const coord_t max_gap_scaled = (coord_t)scale_(max_gap);
|
||
|
|
|
||
|
|
// Sort the open polylines by their length, so the new loops will be seeded from longer chains.
|
||
|
|
// Update the polyline lengths, return only not yet consumed polylines.
|
||
|
|
std::vector<OpenPolyline*> sorted_by_length = open_polylines_sorted(open_polylines, true);
|
||
|
|
|
||
|
|
// Store the end points of open_polylines into ClosestPointInRadiusLookup<OpenPolylineEnd>.
|
||
|
|
struct OpenPolylineEnd {
|
||
|
|
OpenPolylineEnd(OpenPolyline *polyline, bool start) : polyline(polyline), start(start) {}
|
||
|
|
OpenPolyline *polyline;
|
||
|
|
// Is it the start or end point?
|
||
|
|
bool start;
|
||
|
|
const Point& point() const { return start ? polyline->points.front() : polyline->points.back(); }
|
||
|
|
bool operator==(const OpenPolylineEnd &rhs) const { return this->polyline == rhs.polyline && this->start == rhs.start; }
|
||
|
|
};
|
||
|
|
struct OpenPolylineEndAccessor {
|
||
|
|
const Point* operator()(const OpenPolylineEnd &pt) const { return pt.polyline->consumed ? nullptr : &pt.point(); }
|
||
|
|
};
|
||
|
|
typedef ClosestPointInRadiusLookup<OpenPolylineEnd, OpenPolylineEndAccessor> ClosestPointLookupType;
|
||
|
|
ClosestPointLookupType closest_end_point_lookup(max_gap_scaled);
|
||
|
|
for (OpenPolyline *opl : sorted_by_length) {
|
||
|
|
closest_end_point_lookup.insert(OpenPolylineEnd(opl, true));
|
||
|
|
if (try_connect_reversed)
|
||
|
|
closest_end_point_lookup.insert(OpenPolylineEnd(opl, false));
|
||
|
|
}
|
||
|
|
// Try to connect the loops.
|
||
|
|
for (OpenPolyline *opl : sorted_by_length) {
|
||
|
|
if (opl->consumed)
|
||
|
|
continue;
|
||
|
|
OpenPolylineEnd end(opl, false);
|
||
|
|
if (try_connect_reversed)
|
||
|
|
// The end point of this polyline will be modified, thus the following entry will become invalid. Remove it.
|
||
|
|
closest_end_point_lookup.erase(end);
|
||
|
|
opl->consumed = true;
|
||
|
|
size_t n_segments_joined = 1;
|
||
|
|
for (;;) {
|
||
|
|
// Find a line starting where last one finishes, only return non-consumed open polylines (OpenPolylineEndAccessor returns null for consumed).
|
||
|
|
std::pair<const OpenPolylineEnd*, double> next_start_and_dist = closest_end_point_lookup.find(end.point());
|
||
|
|
const OpenPolylineEnd *next_start = next_start_and_dist.first;
|
||
|
|
// Check whether we closed this loop.
|
||
|
|
double current_loop_closing_distance2 = (opl->points.back() - opl->points.front()).cast<double>().squaredNorm();
|
||
|
|
bool loop_closed = current_loop_closing_distance2 < coordf_t(max_gap_scaled) * coordf_t(max_gap_scaled);
|
||
|
|
if (next_start != nullptr && loop_closed && current_loop_closing_distance2 < next_start_and_dist.second) {
|
||
|
|
// Heuristics to decide, whether to close the loop, or connect another polyline.
|
||
|
|
// One should avoid closing loops shorter than max_gap_scaled.
|
||
|
|
loop_closed = sqrt(current_loop_closing_distance2) < 0.3 * length(opl->points);
|
||
|
|
}
|
||
|
|
if (loop_closed) {
|
||
|
|
// Remove the start point of the current polyline from the lookup.
|
||
|
|
// Mark the current segment as not consumed, otherwise the closest_end_point_lookup.erase() would fail.
|
||
|
|
opl->consumed = false;
|
||
|
|
closest_end_point_lookup.erase(OpenPolylineEnd(opl, true));
|
||
|
|
if (current_loop_closing_distance2 == 0.) {
|
||
|
|
// Remove the duplicate last point.
|
||
|
|
opl->points.pop_back();
|
||
|
|
} else {
|
||
|
|
// The end points are different, keep both of them.
|
||
|
|
}
|
||
|
|
if (opl->points.size() >= 3) {
|
||
|
|
if (try_connect_reversed && n_segments_joined > 1 && area(opl->points) < 0)
|
||
|
|
// The closed polygon is patched from pieces with messed up orientation, therefore
|
||
|
|
// the orientation of the patched up polygon is not known.
|
||
|
|
// Orient the patched up polygons CCW. This heuristic may close some holes and cavities.
|
||
|
|
std::reverse(opl->points.begin(), opl->points.end());
|
||
|
|
loops.emplace_back(std::move(opl->points));
|
||
|
|
}
|
||
|
|
opl->points.clear();
|
||
|
|
opl->consumed = true;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (next_start == nullptr) {
|
||
|
|
// The current loop could not be closed. Unmark the segment.
|
||
|
|
opl->consumed = false;
|
||
|
|
if (try_connect_reversed)
|
||
|
|
// Re-insert the end point.
|
||
|
|
closest_end_point_lookup.insert(OpenPolylineEnd(opl, false));
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
// Attach this polyline to the end of the initial polyline.
|
||
|
|
if (next_start->start) {
|
||
|
|
auto it = next_start->polyline->points.begin();
|
||
|
|
if (*it == opl->points.back())
|
||
|
|
++ it;
|
||
|
|
std::copy(it, next_start->polyline->points.end(), back_inserter(opl->points));
|
||
|
|
} else {
|
||
|
|
auto it = next_start->polyline->points.rbegin();
|
||
|
|
if (*it == opl->points.back())
|
||
|
|
++ it;
|
||
|
|
std::copy(it, next_start->polyline->points.rend(), back_inserter(opl->points));
|
||
|
|
}
|
||
|
|
++ n_segments_joined;
|
||
|
|
// Remove the end points of the consumed polyline segment from the lookup.
|
||
|
|
OpenPolyline *opl2 = next_start->polyline;
|
||
|
|
closest_end_point_lookup.erase(OpenPolylineEnd(opl2, true));
|
||
|
|
if (try_connect_reversed)
|
||
|
|
closest_end_point_lookup.erase(OpenPolylineEnd(opl2, false));
|
||
|
|
opl2->points.clear();
|
||
|
|
opl2->consumed = true;
|
||
|
|
// Continue with the current loop.
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
static void make_loops(std::vector<IntersectionLine> &lines, Polygons* loops)
|
||
|
|
{
|
||
|
|
#if 0
|
||
|
|
//FIXME slice_facet() may create zero length edges due to rounding of doubles into coord_t.
|
||
|
|
//#ifdef _DEBUG
|
||
|
|
for (const Line &l : lines)
|
||
|
|
assert(l.a != l.b);
|
||
|
|
#endif /* _DEBUG */
|
||
|
|
|
||
|
|
// There should be no tangent edges, as the horizontal triangles are ignored and if two triangles touch at a cutting plane,
|
||
|
|
// only the bottom triangle is considered to be cutting the plane.
|
||
|
|
// remove_tangent_edges(lines);
|
||
|
|
|
||
|
|
#ifdef SLIC3R_DEBUG_SLICE_PROCESSING
|
||
|
|
BoundingBox bbox_svg;
|
||
|
|
{
|
||
|
|
static int iRun = 0;
|
||
|
|
for (const Line &line : lines) {
|
||
|
|
bbox_svg.merge(line.a);
|
||
|
|
bbox_svg.merge(line.b);
|
||
|
|
}
|
||
|
|
SVG svg(debug_out_path("TriangleMeshSlicer_make_loops-raw_lines-%d.svg", iRun ++).c_str(), bbox_svg);
|
||
|
|
for (const Line &line : lines)
|
||
|
|
svg.draw(line);
|
||
|
|
svg.Close();
|
||
|
|
}
|
||
|
|
#endif /* SLIC3R_DEBUG_SLICE_PROCESSING */
|
||
|
|
|
||
|
|
std::vector<OpenPolyline> open_polylines;
|
||
|
|
chain_lines_by_triangle_connectivity(lines, *loops, open_polylines);
|
||
|
|
|
||
|
|
#ifdef SLIC3R_DEBUG_SLICE_PROCESSING
|
||
|
|
{
|
||
|
|
static int iRun = 0;
|
||
|
|
SVG svg(debug_out_path("TriangleMeshSlicer_make_loops-polylines-%d.svg", iRun ++).c_str(), bbox_svg);
|
||
|
|
svg.draw(union_ex(*loops));
|
||
|
|
for (const OpenPolyline &pl : open_polylines)
|
||
|
|
svg.draw(Polyline(pl.points), "red");
|
||
|
|
svg.Close();
|
||
|
|
}
|
||
|
|
#endif /* SLIC3R_DEBUG_SLICE_PROCESSING */
|
||
|
|
|
||
|
|
// Now process the open polylines.
|
||
|
|
// Do it in two rounds, first try to connect in the same direction only,
|
||
|
|
// then try to connect the open polylines in reversed order as well.
|
||
|
|
chain_open_polylines_exact(open_polylines, *loops, false);
|
||
|
|
chain_open_polylines_exact(open_polylines, *loops, true);
|
||
|
|
|
||
|
|
#ifdef SLIC3R_DEBUG_SLICE_PROCESSING
|
||
|
|
{
|
||
|
|
static int iRun = 0;
|
||
|
|
SVG svg(debug_out_path("TriangleMeshSlicer_make_loops-polylines2-%d.svg", iRun++).c_str(), bbox_svg);
|
||
|
|
svg.draw(union_ex(*loops));
|
||
|
|
for (const OpenPolyline &pl : open_polylines) {
|
||
|
|
if (pl.points.empty())
|
||
|
|
continue;
|
||
|
|
svg.draw(Polyline(pl.points), "red");
|
||
|
|
svg.draw(pl.points.front(), "blue");
|
||
|
|
svg.draw(pl.points.back(), "blue");
|
||
|
|
}
|
||
|
|
svg.Close();
|
||
|
|
}
|
||
|
|
#endif /* SLIC3R_DEBUG_SLICE_PROCESSING */
|
||
|
|
|
||
|
|
// Try to close gaps.
|
||
|
|
// Do it in two rounds, first try to connect in the same direction only,
|
||
|
|
// then try to connect the open polylines in reversed order as well.
|
||
|
|
#if 0
|
||
|
|
for (double max_gap : { EPSILON, 0.001, 0.1, 1., 2. }) {
|
||
|
|
chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, false);
|
||
|
|
chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, true);
|
||
|
|
}
|
||
|
|
#else
|
||
|
|
const double max_gap = 2.; //mm
|
||
|
|
chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, false);
|
||
|
|
chain_open_polylines_close_gaps(open_polylines, *loops, max_gap, true);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifdef SLIC3R_DEBUG_SLICE_PROCESSING
|
||
|
|
{
|
||
|
|
static int iRun = 0;
|
||
|
|
SVG svg(debug_out_path("TriangleMeshSlicer_make_loops-polylines-final-%d.svg", iRun++).c_str(), bbox_svg);
|
||
|
|
svg.draw(union_ex(*loops));
|
||
|
|
for (const OpenPolyline &pl : open_polylines) {
|
||
|
|
if (pl.points.empty())
|
||
|
|
continue;
|
||
|
|
svg.draw(Polyline(pl.points), "red");
|
||
|
|
svg.draw(pl.points.front(), "blue");
|
||
|
|
svg.draw(pl.points.back(), "blue");
|
||
|
|
}
|
||
|
|
svg.Close();
|
||
|
|
}
|
||
|
|
#endif /* SLIC3R_DEBUG_SLICE_PROCESSING */
|
||
|
|
}
|
||
|
|
|
||
|
|
// Used to cut the mesh into two halves.
|
||
|
|
static ExPolygons make_expolygons_simple(std::vector<IntersectionLine> &lines)
|
||
|
|
{
|
||
|
|
ExPolygons slices;
|
||
|
|
Polygons holes;
|
||
|
|
|
||
|
|
{
|
||
|
|
Polygons loops;
|
||
|
|
make_loops(lines, &loops);
|
||
|
|
for (Polygon &loop : loops)
|
||
|
|
if (loop.area() >= 0.)
|
||
|
|
slices.emplace_back(std::move(loop));
|
||
|
|
else
|
||
|
|
holes.emplace_back(std::move(loop));
|
||
|
|
}
|
||
|
|
|
||
|
|
// If there are holes, then there should also be outer contours.
|
||
|
|
assert(holes.empty() || ! slices.empty());
|
||
|
|
if (! slices.empty())
|
||
|
|
{
|
||
|
|
// Assign holes to outer contours.
|
||
|
|
for (Polygon &hole : holes) {
|
||
|
|
// Find an outer contour to a hole.
|
||
|
|
int slice_idx = -1;
|
||
|
|
double current_contour_area = std::numeric_limits<double>::max();
|
||
|
|
for (ExPolygon &slice : slices)
|
||
|
|
if (slice.contour.contains(hole.points.front())) {
|
||
|
|
double area = slice.contour.area();
|
||
|
|
if (area < current_contour_area) {
|
||
|
|
slice_idx = &slice - slices.data();
|
||
|
|
current_contour_area = area;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// assert(slice_idx != -1);
|
||
|
|
if (slice_idx == -1)
|
||
|
|
// Ignore this hole.
|
||
|
|
continue;
|
||
|
|
assert(current_contour_area < std::numeric_limits<double>::max() && current_contour_area >= -hole.area());
|
||
|
|
slices[slice_idx].holes.emplace_back(std::move(hole));
|
||
|
|
}
|
||
|
|
|
||
|
|
#if 0
|
||
|
|
// If the input mesh is not valid, the holes may intersect with the external contour.
|
||
|
|
// Rather subtract them from the outer contour.
|
||
|
|
Polygons poly;
|
||
|
|
for (auto it_slice = slices->begin(); it_slice != slices->end(); ++ it_slice) {
|
||
|
|
if (it_slice->holes.empty()) {
|
||
|
|
poly.emplace_back(std::move(it_slice->contour));
|
||
|
|
} else {
|
||
|
|
Polygons contours;
|
||
|
|
contours.emplace_back(std::move(it_slice->contour));
|
||
|
|
for (auto it = it_slice->holes.begin(); it != it_slice->holes.end(); ++ it)
|
||
|
|
it->reverse();
|
||
|
|
polygons_append(poly, diff(contours, it_slice->holes));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// If the input mesh is not valid, the input contours may intersect.
|
||
|
|
*slices = union_ex(poly);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#if 0
|
||
|
|
// If the input mesh is not valid, the holes may intersect with the external contour.
|
||
|
|
// Rather subtract them from the outer contour.
|
||
|
|
ExPolygons poly;
|
||
|
|
for (auto it_slice = slices->begin(); it_slice != slices->end(); ++ it_slice) {
|
||
|
|
Polygons contours;
|
||
|
|
contours.emplace_back(std::move(it_slice->contour));
|
||
|
|
for (auto it = it_slice->holes.begin(); it != it_slice->holes.end(); ++ it)
|
||
|
|
it->reverse();
|
||
|
|
expolygons_append(poly, diff_ex(contours, it_slice->holes));
|
||
|
|
}
|
||
|
|
// If the input mesh is not valid, the input contours may intersect.
|
||
|
|
*slices = std::move(poly);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
return slices;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void make_expolygons(const Polygons &loops, const float closing_radius, const float extra_offset, ExPolygons* slices)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
Input loops are not suitable for evenodd nor nonzero fill types, as we might get
|
||
|
|
two consecutive concentric loops having the same winding order - and we have to
|
||
|
|
respect such order. In that case, evenodd would create wrong inversions, and nonzero
|
||
|
|
would ignore holes inside two concentric contours.
|
||
|
|
So we're ordering loops and collapse consecutive concentric loops having the same
|
||
|
|
winding order.
|
||
|
|
TODO: find a faster algorithm for this, maybe with some sort of binary search.
|
||
|
|
If we computed a "nesting tree" we could also just remove the consecutive loops
|
||
|
|
having the same winding order, and remove the extra one(s) so that we could just
|
||
|
|
supply everything to offset() instead of performing several union/diff calls.
|
||
|
|
|
||
|
|
we sort by area assuming that the outermost loops have larger area;
|
||
|
|
the previous sorting method, based on $b->contains($a->[0]), failed to nest
|
||
|
|
loops correctly in some edge cases when original model had overlapping facets
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* The following lines are commented out because they can generate wrong polygons,
|
||
|
|
see for example issue #661 */
|
||
|
|
|
||
|
|
//std::vector<double> area;
|
||
|
|
//std::vector<size_t> sorted_area; // vector of indices
|
||
|
|
//for (Polygons::const_iterator loop = loops.begin(); loop != loops.end(); ++ loop) {
|
||
|
|
// area.emplace_back(loop->area());
|
||
|
|
// sorted_area.emplace_back(loop - loops.begin());
|
||
|
|
//}
|
||
|
|
//
|
||
|
|
//// outer first
|
||
|
|
//std::sort(sorted_area.begin(), sorted_area.end(),
|
||
|
|
// [&area](size_t a, size_t b) { return std::abs(area[a]) > std::abs(area[b]); });
|
||
|
|
|
||
|
|
//// we don't perform a safety offset now because it might reverse cw loops
|
||
|
|
//Polygons p_slices;
|
||
|
|
//for (std::vector<size_t>::const_iterator loop_idx = sorted_area.begin(); loop_idx != sorted_area.end(); ++ loop_idx) {
|
||
|
|
// /* we rely on the already computed area to determine the winding order
|
||
|
|
// of the loops, since the Orientation() function provided by Clipper
|
||
|
|
// would do the same, thus repeating the calculation */
|
||
|
|
// Polygons::const_iterator loop = loops.begin() + *loop_idx;
|
||
|
|
// if (area[*loop_idx] > +EPSILON)
|
||
|
|
// p_slices.emplace_back(*loop);
|
||
|
|
// else if (area[*loop_idx] < -EPSILON)
|
||
|
|
// //FIXME This is arbitrary and possibly very slow.
|
||
|
|
// // If the hole is inside a polygon, then there is no need to diff.
|
||
|
|
// // If the hole intersects a polygon boundary, then diff it, but then
|
||
|
|
// // there is no guarantee of an ordering of the loops.
|
||
|
|
// // Maybe we can test for the intersection before running the expensive diff algorithm?
|
||
|
|
// p_slices = diff(p_slices, *loop);
|
||
|
|
//}
|
||
|
|
|
||
|
|
// Perform a safety offset to merge very close facets (TODO: find test case for this)
|
||
|
|
// 0.0499 comes from https://github.com/slic3r/Slic3r/issues/959
|
||
|
|
// double safety_offset = scale_(0.0499);
|
||
|
|
// 0.0001 is set to satisfy GH #520, #1029, #1364
|
||
|
|
assert(closing_radius >= 0);
|
||
|
|
assert(extra_offset >= 0);
|
||
|
|
double offset_out = + scale_(closing_radius + extra_offset);
|
||
|
|
double offset_in = - scale_(closing_radius);
|
||
|
|
|
||
|
|
/* The following line is commented out because it can generate wrong polygons,
|
||
|
|
see for example issue #661 */
|
||
|
|
//ExPolygons ex_slices = offset2_ex(p_slices, +safety_offset, -safety_offset);
|
||
|
|
|
||
|
|
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
|
||
|
|
size_t holes_count = 0;
|
||
|
|
for (ExPolygons::const_iterator e = ex_slices.begin(); e != ex_slices.end(); ++ e)
|
||
|
|
holes_count += e->holes.size();
|
||
|
|
printf("%zu surface(s) having %zu holes detected from %zu polylines\n",
|
||
|
|
ex_slices.size(), holes_count, loops.size());
|
||
|
|
#endif
|
||
|
|
|
||
|
|
// append to the supplied collection
|
||
|
|
expolygons_append(*slices,
|
||
|
|
offset_out > 0 && offset_in < 0 ? offset2_ex(union_ex(loops), offset_out, offset_in) :
|
||
|
|
offset_out > 0 ? offset_ex(union_ex(loops), offset_out) :
|
||
|
|
offset_in < 0 ? offset_ex(union_ex(loops), offset_in) :
|
||
|
|
union_ex(loops));
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
static void make_expolygons(std::vector<IntersectionLine> &lines, const float closing_radius, ExPolygons* slices)
|
||
|
|
{
|
||
|
|
Polygons pp;
|
||
|
|
make_loops(lines, &pp);
|
||
|
|
Slic3r::make_expolygons(pp, closing_radius, 0.f, slices);
|
||
|
|
}
|
||
|
|
*/
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::init(const TriangleMesh *mesh, throw_on_cancel_callback_type throw_on_cancel)
|
||
|
|
{
|
||
|
|
if (! mesh->has_shared_vertices())
|
||
|
|
throw Slic3r::InvalidArgument("TriangleMeshSlicer was passed a mesh without shared vertices.");
|
||
|
|
|
||
|
|
this->init(&mesh->its, throw_on_cancel);
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::init(const indexed_triangle_set *its, throw_on_cancel_callback_type throw_on_cancel)
|
||
|
|
{
|
||
|
|
m_its = its;
|
||
|
|
facets_edges = create_face_neighbors_index(*its, throw_on_cancel);
|
||
|
|
v_scaled_shared.assign(its->vertices.size(), stl_vertex());
|
||
|
|
for (size_t i = 0; i < v_scaled_shared.size(); ++ i)
|
||
|
|
this->v_scaled_shared[i] = its->vertices[i] / float(SCALING_FACTOR);
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::set_up_direction(const Vec3f& up)
|
||
|
|
{
|
||
|
|
m_quaternion.setFromTwoVectors(up, Vec3f::UnitZ());
|
||
|
|
m_use_quaternion = true;
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::slice(
|
||
|
|
const std::vector<float> &z,
|
||
|
|
const MeshSlicingParams ¶ms,
|
||
|
|
std::vector<Polygons> *layers,
|
||
|
|
throw_on_cancel_callback_type throw_on_cancel) const
|
||
|
|
{
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::slice";
|
||
|
|
|
||
|
|
/*
|
||
|
|
This method gets called with a list of unscaled Z coordinates and outputs
|
||
|
|
a vector pointer having the same number of items as the original list.
|
||
|
|
Each item is a vector of polygons created by slicing our mesh at the
|
||
|
|
given heights.
|
||
|
|
|
||
|
|
This method should basically combine the behavior of the existing
|
||
|
|
Perl methods defined in lib/Slic3r/TriangleMesh.pm:
|
||
|
|
|
||
|
|
- analyze(): this creates the 'facets_edges' and the 'edges_facets'
|
||
|
|
tables (we don't need the 'edges' table)
|
||
|
|
|
||
|
|
- slice_facet(): this has to be done for each facet. It generates
|
||
|
|
intersection lines with each plane identified by the Z list.
|
||
|
|
The get_layer_range() binary search used to identify the Z range
|
||
|
|
of the facet is already ported to C++ (see Object.xsp)
|
||
|
|
|
||
|
|
- make_loops(): this has to be done for each layer. It creates polygons
|
||
|
|
from the lines generated by the previous step.
|
||
|
|
|
||
|
|
At the end, we free the tables generated by analyze() as we don't
|
||
|
|
need them anymore.
|
||
|
|
|
||
|
|
NOTE: this method accepts a vector of floats because the mesh coordinate
|
||
|
|
type is float.
|
||
|
|
*/
|
||
|
|
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::slice_facet_at_zs";
|
||
|
|
std::vector<IntersectionLines> lines(z.size());
|
||
|
|
{
|
||
|
|
std::vector<float> scaled_z(z);
|
||
|
|
for (float &z : scaled_z)
|
||
|
|
z = scaled<float>(z);
|
||
|
|
boost::mutex lines_mutex;
|
||
|
|
tbb::parallel_for(
|
||
|
|
tbb::blocked_range<int>(0, int(m_its->indices.size())),
|
||
|
|
[&lines, &lines_mutex, &scaled_z, throw_on_cancel, this](const tbb::blocked_range<int>& range) {
|
||
|
|
const Eigen::Quaternion<float, Eigen::DontAlign> *rotation = m_use_quaternion ? &m_quaternion : nullptr;
|
||
|
|
for (int facet_idx = range.begin(); facet_idx < range.end(); ++ facet_idx) {
|
||
|
|
if ((facet_idx & 0x0ffff) == 0)
|
||
|
|
throw_on_cancel();
|
||
|
|
slice_facet_at_zs(m_its->indices[facet_idx], this->v_scaled_shared, this->facets_edges.data() + facet_idx * 3, rotation, &lines, &lines_mutex, scaled_z);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
);
|
||
|
|
}
|
||
|
|
throw_on_cancel();
|
||
|
|
|
||
|
|
// v_scaled_shared could be freed here
|
||
|
|
|
||
|
|
// build loops
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::_make_loops_do";
|
||
|
|
layers->resize(z.size());
|
||
|
|
tbb::parallel_for(
|
||
|
|
tbb::blocked_range<size_t>(0, z.size()),
|
||
|
|
[&lines, &layers, ¶ms, throw_on_cancel](const tbb::blocked_range<size_t>& range) {
|
||
|
|
for (size_t line_idx = range.begin(); line_idx < range.end(); ++ line_idx) {
|
||
|
|
if ((line_idx & 0x0ffff) == 0)
|
||
|
|
throw_on_cancel();
|
||
|
|
|
||
|
|
Polygons &polygons = (*layers)[line_idx];
|
||
|
|
make_loops(lines[line_idx], &polygons);
|
||
|
|
|
||
|
|
auto this_mode = line_idx < params.slicing_mode_normal_below_layer ? params.mode_below : params.mode;
|
||
|
|
if (! polygons.empty()) {
|
||
|
|
if (this_mode == SlicingMode::Positive) {
|
||
|
|
// Reorient all loops to be CCW.
|
||
|
|
for (Polygon& p : polygons)
|
||
|
|
p.make_counter_clockwise();
|
||
|
|
} else if (this_mode == SlicingMode::PositiveLargestContour) {
|
||
|
|
// Keep just the largest polygon, make it CCW.
|
||
|
|
double max_area = 0.;
|
||
|
|
Polygon* max_area_polygon = nullptr;
|
||
|
|
for (Polygon& p : polygons) {
|
||
|
|
double a = p.area();
|
||
|
|
if (std::abs(a) > std::abs(max_area)) {
|
||
|
|
max_area = a;
|
||
|
|
max_area_polygon = &p;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
assert(max_area_polygon != nullptr);
|
||
|
|
if (max_area < 0.)
|
||
|
|
max_area_polygon->reverse();
|
||
|
|
Polygon p(std::move(*max_area_polygon));
|
||
|
|
polygons.clear();
|
||
|
|
polygons.emplace_back(std::move(p));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
);
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::slice finished";
|
||
|
|
|
||
|
|
#ifdef SLIC3R_DEBUG
|
||
|
|
{
|
||
|
|
static int iRun = 0;
|
||
|
|
for (size_t i = 0; i < z.size(); ++ i) {
|
||
|
|
Polygons &polygons = (*layers)[i];
|
||
|
|
ExPolygons expolygons = union_ex(polygons, true);
|
||
|
|
SVG::export_expolygons(debug_out_path("slice_%d_%d.svg", iRun, i).c_str(), expolygons);
|
||
|
|
{
|
||
|
|
BoundingBox bbox;
|
||
|
|
for (const IntersectionLine &l : lines[i]) {
|
||
|
|
bbox.merge(l.a);
|
||
|
|
bbox.merge(l.b);
|
||
|
|
}
|
||
|
|
SVG svg(debug_out_path("slice_loops_%d_%d.svg", iRun, i).c_str(), bbox);
|
||
|
|
svg.draw(expolygons);
|
||
|
|
for (const IntersectionLine &l : lines[i])
|
||
|
|
svg.draw(l, "red", 0);
|
||
|
|
svg.draw_outline(expolygons, "black", "blue", 0);
|
||
|
|
svg.Close();
|
||
|
|
}
|
||
|
|
#if 0
|
||
|
|
//FIXME slice_facet() may create zero length edges due to rounding of doubles into coord_t.
|
||
|
|
for (Polygon &poly : polygons) {
|
||
|
|
for (size_t i = 1; i < poly.points.size(); ++ i)
|
||
|
|
assert(poly.points[i-1] != poly.points[i]);
|
||
|
|
assert(poly.points.front() != poly.points.back());
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
++ iRun;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::slice(
|
||
|
|
// Where to slice.
|
||
|
|
const std::vector<float> &z,
|
||
|
|
const MeshSlicingParamsExtended ¶ms,
|
||
|
|
std::vector<ExPolygons> *layers,
|
||
|
|
throw_on_cancel_callback_type throw_on_cancel) const
|
||
|
|
{
|
||
|
|
std::vector<Polygons> layers_p;
|
||
|
|
{
|
||
|
|
MeshSlicingParams slicing_params(params);
|
||
|
|
if (params.mode == SlicingMode::PositiveLargestContour)
|
||
|
|
slicing_params.mode = SlicingMode::Positive;
|
||
|
|
if (params.mode_below == SlicingMode::PositiveLargestContour)
|
||
|
|
slicing_params.mode_below = SlicingMode::Positive;
|
||
|
|
this->slice(z, slicing_params, &layers_p, throw_on_cancel);
|
||
|
|
}
|
||
|
|
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::make_expolygons in parallel - start";
|
||
|
|
layers->resize(z.size());
|
||
|
|
tbb::parallel_for(
|
||
|
|
tbb::blocked_range<size_t>(0, z.size()),
|
||
|
|
[&layers_p, ¶ms, layers, throw_on_cancel]
|
||
|
|
(const tbb::blocked_range<size_t>& range) {
|
||
|
|
for (size_t layer_id = range.begin(); layer_id < range.end(); ++ layer_id) {
|
||
|
|
#ifdef SLIC3R_TRIANGLEMESH_DEBUG
|
||
|
|
printf("Layer %zu (slice_z = %.2f):\n", layer_id, z[layer_id]);
|
||
|
|
#endif
|
||
|
|
throw_on_cancel();
|
||
|
|
ExPolygons &expolygons = (*layers)[layer_id];
|
||
|
|
Slic3r::make_expolygons(layers_p[layer_id], params.closing_radius, params.extra_offset, &expolygons);
|
||
|
|
//FIXME simplify
|
||
|
|
const auto this_mode = layer_id < params.slicing_mode_normal_below_layer ? params.mode_below : params.mode;
|
||
|
|
if (this_mode == SlicingMode::PositiveLargestContour)
|
||
|
|
keep_largest_contour_only(expolygons);
|
||
|
|
}
|
||
|
|
});
|
||
|
|
BOOST_LOG_TRIVIAL(debug) << "TriangleMeshSlicer::make_expolygons in parallel - end";
|
||
|
|
}
|
||
|
|
|
||
|
|
static void triangulate_slice(indexed_triangle_set &its, IntersectionLines &lines, const std::vector<int> &slice_vertices, float z)
|
||
|
|
{
|
||
|
|
// BOOST_LOG_TRIVIAL(trace) << "TriangleMeshSlicer::cut - triangulating the cut";
|
||
|
|
|
||
|
|
ExPolygons section = make_expolygons_simple(lines);
|
||
|
|
Pointf3s triangles = triangulate_expolygons_3d(section, z, true);
|
||
|
|
std::vector<std::pair<Vec2f, int>> map_vertex_to_index;
|
||
|
|
map_vertex_to_index.reserve(slice_vertices.size());
|
||
|
|
for (int i : slice_vertices)
|
||
|
|
map_vertex_to_index.emplace_back(to_2d(its.vertices[i]), i);
|
||
|
|
std::sort(map_vertex_to_index.begin(), map_vertex_to_index.end(),
|
||
|
|
[](const std::pair<Vec2f, int> &l, const std::pair<Vec2f, int> &r) {
|
||
|
|
return l.first.x() < r.first.x() || (l.first.x() == r.first.x() && l.first.y() < r.first.y()); });
|
||
|
|
size_t idx_vertex_new_first = its.vertices.size();
|
||
|
|
for (size_t i = 0; i < triangles.size(); ) {
|
||
|
|
stl_triangle_vertex_indices facet;
|
||
|
|
for (size_t j = 0; j < 3; ++ j) {
|
||
|
|
Vec3f v = triangles[i++].cast<float>();
|
||
|
|
auto it = lower_bound_by_predicate(map_vertex_to_index.begin(), map_vertex_to_index.end(),
|
||
|
|
[&v](const std::pair<Vec2f, int> &l) { return l.first.x() < v.x() || (l.first.x() == v.x() && l.first.y() < v.y()); });
|
||
|
|
int idx = -1;
|
||
|
|
if (it != map_vertex_to_index.end() && it->first.x() == v.x() && it->first.y() == v.y())
|
||
|
|
idx = it->second;
|
||
|
|
else {
|
||
|
|
// Try to find the vertex in the list of newly added vertices. Those vertices are not matched on the cut and they shall be rare.
|
||
|
|
for (size_t k = idx_vertex_new_first; k < its.vertices.size(); ++ k)
|
||
|
|
if (its.vertices[k] == v) {
|
||
|
|
idx = int(k);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (idx == -1) {
|
||
|
|
idx = int(its.vertices.size());
|
||
|
|
its.vertices.emplace_back(v);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
facet(j) = idx;
|
||
|
|
}
|
||
|
|
its.indices.emplace_back(facet);
|
||
|
|
}
|
||
|
|
|
||
|
|
its_compactify_vertices(its);
|
||
|
|
its_remove_degenerate_faces(its);
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::cut(float z, indexed_triangle_set *upper, indexed_triangle_set *lower) const
|
||
|
|
{
|
||
|
|
assert(upper || lower);
|
||
|
|
if (upper == nullptr && lower == nullptr)
|
||
|
|
return;
|
||
|
|
|
||
|
|
if (upper) {
|
||
|
|
upper->clear();
|
||
|
|
upper->vertices = m_its->vertices;
|
||
|
|
upper->indices.reserve(m_its->indices.size());
|
||
|
|
}
|
||
|
|
if (lower) {
|
||
|
|
lower->clear();
|
||
|
|
lower->vertices = m_its->vertices;
|
||
|
|
lower->indices.reserve(m_its->indices.size());
|
||
|
|
}
|
||
|
|
|
||
|
|
BOOST_LOG_TRIVIAL(trace) << "TriangleMeshSlicer::cut - slicing object";
|
||
|
|
const auto scaled_z = scaled<float>(z);
|
||
|
|
|
||
|
|
// To triangulate the caps after slicing.
|
||
|
|
IntersectionLines upper_lines, lower_lines;
|
||
|
|
std::vector<int> upper_slice_vertices, lower_slice_vertices;
|
||
|
|
|
||
|
|
for (int facet_idx = 0; facet_idx < int(m_its->indices.size()); ++ facet_idx) {
|
||
|
|
const stl_triangle_vertex_indices &facet = m_its->indices[facet_idx];
|
||
|
|
Vec3f vertices[3] { m_its->vertices[facet(0)], m_its->vertices[facet(1)], m_its->vertices[facet(2)] };
|
||
|
|
stl_vertex vertices_scaled[3]{ this->v_scaled_shared[facet[0]], this->v_scaled_shared[facet[1]], this->v_scaled_shared[facet[2]] };
|
||
|
|
float min_z = std::min(vertices[0].z(), std::min(vertices[1].z(), vertices[2].z()));
|
||
|
|
float max_z = std::max(vertices[0].z(), std::max(vertices[1].z(), vertices[2].z()));
|
||
|
|
|
||
|
|
// intersect facet with cutting plane
|
||
|
|
IntersectionLine line;
|
||
|
|
int idx_vertex_lowest = (vertices[1].z() == min_z) ? 1 : ((vertices[2].z() == min_z) ? 2 : 0);
|
||
|
|
FacetSliceType slice_type = slice_facet(scaled_z, vertices_scaled, m_its->indices[facet_idx], this->facets_edges.data() + facet_idx * 3, idx_vertex_lowest, min_z == max_z, &line);
|
||
|
|
if (slice_type != FacetSliceType::NoSlice) {
|
||
|
|
// Save intersection lines for generating correct triangulations.
|
||
|
|
if (line.edge_type == IntersectionLine::FacetEdgeType::Top) {
|
||
|
|
lower_lines.emplace_back(line);
|
||
|
|
lower_slice_vertices.emplace_back(line.a_id);
|
||
|
|
lower_slice_vertices.emplace_back(line.b_id);
|
||
|
|
} else if (line.edge_type == IntersectionLine::FacetEdgeType::Bottom) {
|
||
|
|
upper_lines.emplace_back(line);
|
||
|
|
upper_slice_vertices.emplace_back(line.a_id);
|
||
|
|
upper_slice_vertices.emplace_back(line.b_id);
|
||
|
|
} else if (line.edge_type == IntersectionLine::FacetEdgeType::General) {
|
||
|
|
lower_lines.emplace_back(line);
|
||
|
|
upper_lines.emplace_back(line);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (min_z > z || (min_z == z && max_z > z)) {
|
||
|
|
// facet is above the cut plane and does not belong to it
|
||
|
|
if (upper != nullptr)
|
||
|
|
upper->indices.emplace_back(facet);
|
||
|
|
} else if (max_z < z || (max_z == z && min_z < z)) {
|
||
|
|
// facet is below the cut plane and does not belong to it
|
||
|
|
if (lower != nullptr)
|
||
|
|
lower->indices.emplace_back(facet);
|
||
|
|
} else if (min_z < z && max_z > z) {
|
||
|
|
// Facet is cut by the slicing plane.
|
||
|
|
assert(slice_type == FacetSliceType::Slicing);
|
||
|
|
assert(line.edge_type == IntersectionLine::FacetEdgeType::General);
|
||
|
|
|
||
|
|
// look for the vertex on whose side of the slicing plane there are no other vertices
|
||
|
|
int isolated_vertex =
|
||
|
|
(vertices[0].z() > z) == (vertices[1].z() > z) ? 2 :
|
||
|
|
(vertices[1].z() > z) == (vertices[2].z() > z) ? 0 : 1;
|
||
|
|
|
||
|
|
// get vertices starting from the isolated one
|
||
|
|
int iv = isolated_vertex;
|
||
|
|
const stl_vertex &v0 = vertices[iv];
|
||
|
|
const int iv0 = facet[iv];
|
||
|
|
if (++ iv == 3)
|
||
|
|
iv = 0;
|
||
|
|
const stl_vertex &v1 = vertices[iv];
|
||
|
|
const int iv1 = facet[iv];
|
||
|
|
if (++ iv == 3)
|
||
|
|
iv = 0;
|
||
|
|
const stl_vertex &v2 = vertices[iv];
|
||
|
|
const int iv2 = facet[iv];
|
||
|
|
|
||
|
|
// intersect v0-v1 and v2-v0 with cutting plane and make new vertices
|
||
|
|
auto new_vertex = [upper, lower, &upper_slice_vertices, &lower_slice_vertices](const Vec3f &a, const int ia, const Vec3f &b, const int ib, float z, float t) {
|
||
|
|
int iupper, ilower;
|
||
|
|
if (t <= 0.f)
|
||
|
|
iupper = ilower = ia;
|
||
|
|
else if (t >= 1.f)
|
||
|
|
iupper = ilower = ib;
|
||
|
|
else {
|
||
|
|
const stl_vertex c = Vec3f(lerp(a.x(), b.x(), t), lerp(a.y(), b.y(), t), z);
|
||
|
|
if (c == a)
|
||
|
|
iupper = ilower = ia;
|
||
|
|
else if (c == b)
|
||
|
|
iupper = ilower = ib;
|
||
|
|
else {
|
||
|
|
// Insert a new vertex into upper / lower.
|
||
|
|
if (upper) {
|
||
|
|
iupper = int(upper->vertices.size());
|
||
|
|
upper->vertices.emplace_back(c);
|
||
|
|
upper_slice_vertices.emplace_back(iupper);
|
||
|
|
}
|
||
|
|
if (lower) {
|
||
|
|
ilower = int(lower->vertices.size());
|
||
|
|
lower->vertices.emplace_back(c);
|
||
|
|
lower_slice_vertices.emplace_back(ilower);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return std::make_pair(iupper, ilower);
|
||
|
|
};
|
||
|
|
auto [iv0v1_upper, iv0v1_lower] = new_vertex(v1, iv1, v0, iv0, z, (z - v1.z()) / (v0.z() - v1.z()));
|
||
|
|
auto [iv2v0_upper, iv2v0_lower] = new_vertex(v2, iv2, v0, iv0, z, (z - v2.z()) / (v0.z() - v2.z()));
|
||
|
|
|
||
|
|
if (v0(2) > z) {
|
||
|
|
if (upper != nullptr)
|
||
|
|
upper->indices.emplace_back(iv0, iv0v1_upper, iv2v0_upper);
|
||
|
|
if (lower != nullptr) {
|
||
|
|
lower->indices.emplace_back(iv1, iv2, iv0v1_lower);
|
||
|
|
lower->indices.emplace_back(iv2, iv2v0_lower, iv0v1_lower);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
if (upper != nullptr) {
|
||
|
|
upper->indices.emplace_back(iv1, iv2, iv0v1_upper);
|
||
|
|
upper->indices.emplace_back(iv2, iv2v0_upper, iv0v1_upper);
|
||
|
|
}
|
||
|
|
if (lower != nullptr)
|
||
|
|
lower->indices.emplace_back(iv0, iv0v1_lower, iv2v0_lower);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (upper != nullptr)
|
||
|
|
triangulate_slice(*upper, upper_lines, upper_slice_vertices, z);
|
||
|
|
|
||
|
|
if (lower != nullptr)
|
||
|
|
triangulate_slice(*lower, lower_lines, lower_slice_vertices, z);
|
||
|
|
}
|
||
|
|
|
||
|
|
void TriangleMeshSlicer::cut(float z, TriangleMesh *upper_mesh, TriangleMesh *lower_mesh) const
|
||
|
|
{
|
||
|
|
indexed_triangle_set upper, lower;
|
||
|
|
this->cut(z, upper_mesh ? &upper : nullptr, lower_mesh ? &lower : nullptr);
|
||
|
|
if (upper_mesh)
|
||
|
|
*upper_mesh = TriangleMesh(upper);
|
||
|
|
if (lower_mesh)
|
||
|
|
*lower_mesh = TriangleMesh(lower);
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|