diff options
Diffstat (limited to 'src/libslic3r/SLA/Pad.cpp')
| -rw-r--r-- | src/libslic3r/SLA/Pad.cpp | 203 |
1 files changed, 22 insertions, 181 deletions
diff --git a/src/libslic3r/SLA/Pad.cpp b/src/libslic3r/SLA/Pad.cpp index cf1786758..927c32589 100644 --- a/src/libslic3r/SLA/Pad.cpp +++ b/src/libslic3r/SLA/Pad.cpp @@ -1,5 +1,4 @@ #include <libslic3r/SLA/Pad.hpp> -#include <libslic3r/SLA/Common.hpp> #include <libslic3r/SLA/SpatIndex.hpp> #include <libslic3r/SLA/BoostAdapter.hpp> #include <libslic3r/SLA/Contour3D.hpp> @@ -11,6 +10,8 @@ #include "Tesselate.hpp" #include "MTUtils.hpp" +#include "TriangulateWall.hpp" + // For debugging: // #include <fstream> // #include <libnest2d/tools/benchmark.h> @@ -27,186 +28,27 @@ namespace Slic3r { namespace sla { namespace { -/// This function will return a triangulation of a sheet connecting an upper -/// and a lower plate given as input polygons. It will not triangulate the -/// plates themselves only the sheet. The caller has to specify the lower and -/// upper z levels in world coordinates as well as the offset difference -/// between the sheets. If the lower_z_mm is higher than upper_z_mm or the -/// offset difference is negative, the resulting triangle orientation will be -/// reversed. -/// -/// IMPORTANT: This is not a universal triangulation algorithm. It assumes -/// that the lower and upper polygons are offsetted versions of the same -/// original polygon. In general, it assumes that one of the polygons is -/// completely inside the other. The offset difference is the reference -/// distance from the inner polygon's perimeter to the outer polygon's -/// perimeter. The real distance will be variable as the clipper offset has -/// different strategies (rounding, etc...). This algorithm should have -/// O(2n + 3m) complexity where n is the number of upper vertices and m is the -/// number of lower vertices. Contour3D walls( const Polygon &lower, const Polygon &upper, double lower_z_mm, - double upper_z_mm, - double offset_difference_mm, - ThrowOnCancel thr = [] {}) + double upper_z_mm) { - Contour3D ret; - - if(upper.points.size() < 3 || lower.size() < 3) return ret; - - // The concept of the algorithm is relatively simple. It will try to find - // the closest vertices from the upper and the lower polygon and use those - // as starting points. Then it will create the triangles sequentially using - // an edge from the upper polygon and a vertex from the lower or vice versa, - // depending on the resulting triangle's quality. - // The quality is measured by a scalar value. So far it looks like it is - // enough to derive it from the slope of the triangle's two edges connecting - // the upper and the lower part. A reference slope is calculated from the - // height and the offset difference. - - // Offset in the index array for the ceiling - const auto offs = upper.points.size(); - - // Shorthand for the vertex arrays - auto& upts = upper.points, &lpts = lower.points; - auto& rpts = ret.points; auto& ind = ret.faces3; - - // If the Z levels are flipped, or the offset difference is negative, we - // will interpret that as the triangles normals should be inverted. - bool inverted = upper_z_mm < lower_z_mm || offset_difference_mm < 0; - - // Copy the points into the mesh, convert them from 2D to 3D - rpts.reserve(upts.size() + lpts.size()); - ind.reserve(2 * upts.size() + 2 * lpts.size()); - for (auto &p : upts) - rpts.emplace_back(unscaled(p.x()), unscaled(p.y()), upper_z_mm); - for (auto &p : lpts) - rpts.emplace_back(unscaled(p.x()), unscaled(p.y()), lower_z_mm); - - // Create pointing indices into vertex arrays. u-upper, l-lower - size_t uidx = 0, lidx = offs, unextidx = 1, lnextidx = offs + 1; - - // Simple squared distance calculation. - auto distfn = [](const Vec3d& p1, const Vec3d& p2) { - auto p = p1 - p2; return p.transpose() * p; - }; - - // We need to find the closest point on lower polygon to the first point on - // the upper polygon. These will be our starting points. - double distmin = std::numeric_limits<double>::max(); - for(size_t l = lidx; l < rpts.size(); ++l) { - thr(); - double d = distfn(rpts[l], rpts[uidx]); - if(d < distmin) { lidx = l; distmin = d; } - } - - // Set up lnextidx to be ahead of lidx in cyclic mode - lnextidx = lidx + 1; - if(lnextidx == rpts.size()) lnextidx = offs; - - // This will be the flip switch to toggle between upper and lower triangle - // creation mode - enum class Proceed { - UPPER, // A segment from the upper polygon and one vertex from the lower - LOWER // A segment from the lower polygon and one vertex from the upper - } proceed = Proceed::UPPER; - - // Flags to help evaluating loop termination. - bool ustarted = false, lstarted = false; - - // The variables for the fitness values, one for the actual and one for the - // previous. - double current_fit = 0, prev_fit = 0; - - // Every triangle of the wall has two edges connecting the upper plate with - // the lower plate. From the length of these two edges and the zdiff we - // can calculate the momentary squared offset distance at a particular - // position on the wall. The average of the differences from the reference - // (squared) offset distance will give us the driving fitness value. - const double offsdiff2 = std::pow(offset_difference_mm, 2); - const double zdiff2 = std::pow(upper_z_mm - lower_z_mm, 2); - - // Mark the current vertex iterator positions. If the iterators return to - // the same position, the loop can be terminated. - size_t uendidx = uidx, lendidx = lidx; - - do { thr(); // check throw if canceled - - prev_fit = current_fit; - - switch(proceed) { // proceed depending on the current state - case Proceed::UPPER: - if(!ustarted || uidx != uendidx) { // there are vertices remaining - // Get the 3D vertices in order - const Vec3d& p_up1 = rpts[uidx]; - const Vec3d& p_low = rpts[lidx]; - const Vec3d& p_up2 = rpts[unextidx]; - - // Calculate fitness: the average of the two connecting edges - double a = offsdiff2 - (distfn(p_up1, p_low) - zdiff2); - double b = offsdiff2 - (distfn(p_up2, p_low) - zdiff2); - current_fit = (std::abs(a) + std::abs(b)) / 2; - - if(current_fit > prev_fit) { // fit is worse than previously - proceed = Proceed::LOWER; - } else { // good to go, create the triangle - inverted - ? ind.emplace_back(int(unextidx), int(lidx), int(uidx)) - : ind.emplace_back(int(uidx), int(lidx), int(unextidx)); - - // Increment the iterators, rotate if necessary - ++uidx; ++unextidx; - if(unextidx == offs) unextidx = 0; - if(uidx == offs) uidx = 0; - - ustarted = true; // mark the movement of the iterators - // so that the comparison to uendidx can be made correctly - } - } else proceed = Proceed::LOWER; - - break; - case Proceed::LOWER: - // Mode with lower segment, upper vertex. Same structure: - if(!lstarted || lidx != lendidx) { - const Vec3d& p_low1 = rpts[lidx]; - const Vec3d& p_low2 = rpts[lnextidx]; - const Vec3d& p_up = rpts[uidx]; - - double a = offsdiff2 - (distfn(p_up, p_low1) - zdiff2); - double b = offsdiff2 - (distfn(p_up, p_low2) - zdiff2); - current_fit = (std::abs(a) + std::abs(b)) / 2; - - if(current_fit > prev_fit) { - proceed = Proceed::UPPER; - } else { - inverted - ? ind.emplace_back(int(uidx), int(lnextidx), int(lidx)) - : ind.emplace_back(int(lidx), int(lnextidx), int(uidx)); - - ++lidx; ++lnextidx; - if(lnextidx == rpts.size()) lnextidx = offs; - if(lidx == rpts.size()) lidx = offs; - - lstarted = true; - } - } else proceed = Proceed::UPPER; - - break; - } // end of switch - } while(!ustarted || !lstarted || uidx != uendidx || lidx != lendidx); + Wall w = triangulate_wall(lower, upper, lower_z_mm, upper_z_mm); + Contour3D ret; + ret.points = std::move(w.first); + ret.faces3 = std::move(w.second); + return ret; } // Same as walls() but with identical higher and lower polygons. Contour3D inline straight_walls(const Polygon &plate, double lo_z, - double hi_z, - ThrowOnCancel thr) + double hi_z) { - return walls(plate, plate, lo_z, hi_z, .0 /*offset_diff*/, thr); + return walls(plate, plate, lo_z, hi_z); } // Function to cut tiny connector cavities for a given polygon. The input poly @@ -527,17 +369,15 @@ bool add_cavity(Contour3D &pad, ExPolygon &top_poly, const PadConfig3D &cfg, if (inner_base.empty() || middle_base.empty()) { logerr(); return false; } - ExPolygons pdiff = diff_ex(top_poly, middle_base.contour); + ExPolygons pdiff = diff_ex((Polygons)top_poly, (Polygons)middle_base.contour); if (pdiff.size() != 1) { logerr(); return false; } top_poly = pdiff.front(); double z_min = -cfg.wing_height, z_max = 0; - double offset_difference = -wing_distance; - pad.merge(walls(inner_base.contour, middle_base.contour, z_min, z_max, - offset_difference, thr)); - + pad.merge(walls(inner_base.contour, middle_base.contour, z_min, z_max)); + thr(); pad.merge(triangulate_expolygon_3d(inner_base, z_min, NORMALS_UP)); return true; @@ -555,17 +395,17 @@ Contour3D create_outer_pad_geometry(const ExPolygons & skeleton, offset_contour_only(pad_part, -scaled(cfg.bottom_offset())); if (bottom_poly.empty()) continue; - + thr(); + double z_min = -cfg.height, z_max = 0; - ret.merge(walls(top_poly.contour, bottom_poly.contour, z_max, z_min, - cfg.bottom_offset(), thr)); + ret.merge(walls(top_poly.contour, bottom_poly.contour, z_max, z_min)); if (cfg.wing_height > 0. && add_cavity(ret, top_poly, cfg, thr)) z_max = -cfg.wing_height; for (auto &h : bottom_poly.holes) - ret.merge(straight_walls(h, z_max, z_min, thr)); - + ret.merge(straight_walls(h, z_max, z_min)); + ret.merge(triangulate_expolygon_3d(bottom_poly, z_min, NORMALS_DOWN)); ret.merge(triangulate_expolygon_3d(top_poly, NORMALS_UP)); } @@ -581,11 +421,12 @@ Contour3D create_inner_pad_geometry(const ExPolygons & skeleton, double z_max = 0., z_min = -cfg.height; for (const ExPolygon &pad_part : skeleton) { - ret.merge(straight_walls(pad_part.contour, z_max, z_min,thr)); + thr(); + ret.merge(straight_walls(pad_part.contour, z_max, z_min)); for (auto &h : pad_part.holes) - ret.merge(straight_walls(h, z_max, z_min, thr)); - + ret.merge(straight_walls(h, z_max, z_min)); + ret.merge(triangulate_expolygon_3d(pad_part, z_min, NORMALS_DOWN)); ret.merge(triangulate_expolygon_3d(pad_part, z_max, NORMALS_UP)); } |