Point
MotionPlanner::nearest_env_point(const ExPolygonCollection &env, const Point &from, const Point &to) const
{
/* In order to ensure that the move between 'from' and the initial env point does
not violate any of the configuration space boundaries, we limit our search to
the points that satisfy this condition. */
/* Assume that this method is never called when 'env' contains 'from';
so 'from' is either inside a hole or outside all contours */
// get the points of the hole containing 'from', if any
Points pp;
for (ExPolygons::const_iterator ex = env.expolygons.begin(); ex != env.expolygons.end(); ++ex) {
for (Polygons::const_iterator h = ex->holes.begin(); h != ex->holes.end(); ++h) {
if (h->contains(from)) {
pp = *h;
}
}
if (!pp.empty()) break;
}
/* If 'from' is not inside a hole, it's outside of all contours, so take all
contours' points */
if (pp.empty()) {
for (ExPolygons::const_iterator ex = env.expolygons.begin(); ex != env.expolygons.end(); ++ex) {
Points contour_pp = ex->contour;
pp.insert(pp.end(), contour_pp.begin(), contour_pp.end());
}
}
/* Find the candidate result and check that it doesn't cross any boundary.
(We could skip all of the above polygon finding logic and directly test all points
in env, but this way we probably reduce complexity). */
Polygons env_pp = env;
while (pp.size() >= 2) {
// find the point in pp that is closest to both 'from' and 'to'
size_t result = from.nearest_waypoint_index(pp, to);
if (intersects((Lines)Line(from, pp[result]), env_pp)) {
// discard result
pp.erase(pp.begin() + result);
} else {
return pp[result];
}
}
// if we're here, return last point if any (better than nothing)
if (!pp.empty()) return pp.front();
// if we have no points at all, then we have an empty environment and we
// make this method behave as a no-op (we shouldn't get here by the way)
return from;
}
void
MotionPlanner::initialize()
{
if (this->initialized) return;
if (this->islands.empty()) return; // prevent initialization of empty BoundingBox
// loop through islands in order to create inner expolygons and collect their contours
Polygons outer_holes;
for (std::vector<MotionPlannerEnv>::iterator island = this->islands.begin(); island != this->islands.end(); ++island) {
// generate the internal env boundaries by shrinking the island
// we'll use these inner rings for motion planning (endpoints of the Voronoi-based
// graph, visibility check) in order to avoid moving too close to the boundaries
island->env = offset_ex(island->island, -MP_INNER_MARGIN);
// island contours are holes of our external environment
outer_holes.push_back(island->island.contour);
}
// generate outer contour as bounding box of everything
BoundingBox bb;
for (Polygons::const_iterator contour = outer_holes.begin(); contour != outer_holes.end(); ++contour)
bb.merge(contour->bounding_box());
// grow outer contour
Polygons contour = offset(bb.polygon(), +MP_OUTER_MARGIN*2);
assert(contour.size() == 1);
// make expolygon for outer environment
ExPolygons outer = diff_ex(contour, outer_holes);
assert(outer.size() == 1);
this->outer.island = outer.front();
this->outer.env = ExPolygonCollection(diff_ex(contour, offset(outer_holes, +MP_OUTER_MARGIN)));
this->graphs.resize(this->islands.size() + 1, NULL);
this->initialized = true;
}
void
PerimeterGenerator::process()
{
// other perimeters
this->_mm3_per_mm = this->perimeter_flow.mm3_per_mm();
coord_t pwidth = this->perimeter_flow.scaled_width();
coord_t pspacing = this->perimeter_flow.scaled_spacing();
// external perimeters
this->_ext_mm3_per_mm = this->ext_perimeter_flow.mm3_per_mm();
coord_t ext_pwidth = this->ext_perimeter_flow.scaled_width();
coord_t ext_pspacing = this->ext_perimeter_flow.scaled_spacing();
coord_t ext_pspacing2 = this->ext_perimeter_flow.scaled_spacing(this->perimeter_flow);
// overhang perimeters
this->_mm3_per_mm_overhang = this->overhang_flow.mm3_per_mm();
// solid infill
coord_t ispacing = this->solid_infill_flow.scaled_spacing();
coord_t gap_area_threshold = pwidth * pwidth;
// Calculate the minimum required spacing between two adjacent traces.
// This should be equal to the nominal flow spacing but we experiment
// with some tolerance in order to avoid triggering medial axis when
// some squishing might work. Loops are still spaced by the entire
// flow spacing; this only applies to collapsing parts.
// For ext_min_spacing we use the ext_pspacing calculated for two adjacent
// external loops (which is the correct way) instead of using ext_pspacing2
// which is the spacing between external and internal, which is not correct
// and would make the collapsing (thus the details resolution) dependent on
// internal flow which is unrelated.
coord_t min_spacing = pspacing * (1 - INSET_OVERLAP_TOLERANCE);
coord_t ext_min_spacing = ext_pspacing * (1 - INSET_OVERLAP_TOLERANCE);
// prepare grown lower layer slices for overhang detection
if (this->lower_slices != NULL && this->config->overhangs) {
// We consider overhang any part where the entire nozzle diameter is not supported by the
// lower layer, so we take lower slices and offset them by half the nozzle diameter used
// in the current layer
double nozzle_diameter = this->print_config->nozzle_diameter.get_at(this->config->perimeter_extruder-1);
this->_lower_slices_p = offset(*this->lower_slices, scale_(+nozzle_diameter/2));
}
// we need to process each island separately because we might have different
// extra perimeters for each one
for (Surfaces::const_iterator surface = this->slices->surfaces.begin();
surface != this->slices->surfaces.end(); ++surface) {
// detect how many perimeters must be generated for this island
signed short loop_number = this->config->perimeters + surface->extra_perimeters;
loop_number--; // 0-indexed loops
Polygons gaps;
Polygons last = surface->expolygon.simplify_p(SCALED_RESOLUTION);
if (loop_number >= 0) { // no loops = -1
std::vector<PerimeterGeneratorLoops> contours(loop_number+1); // depth => loops
std::vector<PerimeterGeneratorLoops> holes(loop_number+1); // depth => loops
Polylines thin_walls;
// we loop one time more than needed in order to find gaps after the last perimeter was applied
for (signed short i = 0; i <= loop_number+1; ++i) { // outer loop is 0
Polygons offsets;
if (i == 0) {
// the minimum thickness of a single loop is:
// ext_width/2 + ext_spacing/2 + spacing/2 + width/2
if (this->config->thin_walls) {
offsets = offset2(
last,
-(ext_pwidth/2 + ext_min_spacing/2 - 1),
+(ext_min_spacing/2 - 1)
);
} else {
offsets = offset(last, -ext_pwidth/2);
}
// look for thin walls
if (this->config->thin_walls) {
Polygons diffpp = diff(
last,
offset(offsets, +ext_pwidth/2),
true // medial axis requires non-overlapping geometry
);
// the following offset2 ensures almost nothing in @thin_walls is narrower than $min_width
// (actually, something larger than that still may exist due to mitering or other causes)
coord_t min_width = ext_pwidth / 2;
ExPolygons expp = offset2_ex(diffpp, -min_width/2, +min_width/2);
// the maximum thickness of our thin wall area is equal to the minimum thickness of a single loop
Polylines pp;
for (ExPolygons::const_iterator ex = expp.begin(); ex != expp.end(); ++ex)
ex->medial_axis(ext_pwidth + ext_pspacing2, min_width, &pp);
double threshold = ext_pwidth * 2;
for (Polylines::const_iterator p = pp.begin(); p != pp.end(); ++p) {
if (p->length() > threshold) {
thin_walls.push_back(*p);
}
}
#ifdef DEBUG
printf(" %zu thin walls detected\n", thin_walls.size());
#endif
/*
if (false) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(
"medial_axis.svg",
no_arrows => 1,
#expolygons => \@expp,
polylines => \@thin_walls,
);
}
*/
}
} else {
coord_t distance = (i == 1) ? ext_pspacing2 : pspacing;
if (this->config->thin_walls) {
offsets = offset2(
last,
-(distance + min_spacing/2 - 1),
+(min_spacing/2 - 1)
);
} else {
offsets = offset(
last,
-distance
);
}
// look for gaps
if (this->config->gap_fill_speed.value > 0 && this->config->fill_density.value > 0) {
// not using safety offset here would "detect" very narrow gaps
// (but still long enough to escape the area threshold) that gap fill
// won't be able to fill but we'd still remove from infill area
ExPolygons diff_expp = diff_ex(
offset(last, -0.5*distance),
offset(offsets, +0.5*distance + 10) // safety offset
);
for (ExPolygons::const_iterator ex = diff_expp.begin(); ex != diff_expp.end(); ++ex) {
if (fabs(ex->area()) >= gap_area_threshold) {
Polygons pp = *ex;
gaps.insert(gaps.end(), pp.begin(), pp.end());
}
}
}
}
if (offsets.empty()) break;
if (i > loop_number) break; // we were only looking for gaps this time
last = offsets;
for (Polygons::const_iterator polygon = offsets.begin(); polygon != offsets.end(); ++polygon) {
PerimeterGeneratorLoop loop(*polygon, i);
loop.is_contour = polygon->is_counter_clockwise();
if (loop.is_contour) {
contours[i].push_back(loop);
} else {
holes[i].push_back(loop);
}
}
}
// nest loops: holes first
for (signed short d = 0; d <= loop_number; ++d) {
PerimeterGeneratorLoops &holes_d = holes[d];
// loop through all holes having depth == d
for (signed short i = 0; i < holes_d.size(); ++i) {
const PerimeterGeneratorLoop &loop = holes_d[i];
// find the hole loop that contains this one, if any
for (signed short t = d+1; t <= loop_number; ++t) {
for (signed short j = 0; j < holes[t].size(); ++j) {
PerimeterGeneratorLoop &candidate_parent = holes[t][j];
if (candidate_parent.polygon.contains(loop.polygon.first_point())) {
candidate_parent.children.push_back(loop);
holes_d.erase(holes_d.begin() + i);
--i;
goto NEXT_LOOP;
}
}
}
// if no hole contains this hole, find the contour loop that contains it
for (signed short t = loop_number; t >= 0; --t) {
for (signed short j = 0; j < contours[t].size(); ++j) {
PerimeterGeneratorLoop &candidate_parent = contours[t][j];
if (candidate_parent.polygon.contains(loop.polygon.first_point())) {
candidate_parent.children.push_back(loop);
holes_d.erase(holes_d.begin() + i);
--i;
goto NEXT_LOOP;
}
}
}
NEXT_LOOP: ;
}
}
// nest contour loops
for (signed short d = loop_number; d >= 1; --d) {
PerimeterGeneratorLoops &contours_d = contours[d];
// loop through all contours having depth == d
for (signed short i = 0; i < contours_d.size(); ++i) {
const PerimeterGeneratorLoop &loop = contours_d[i];
// find the contour loop that contains it
for (signed short t = d-1; t >= 0; --t) {
for (signed short j = 0; j < contours[t].size(); ++j) {
PerimeterGeneratorLoop &candidate_parent = contours[t][j];
if (candidate_parent.polygon.contains(loop.polygon.first_point())) {
candidate_parent.children.push_back(loop);
contours_d.erase(contours_d.begin() + i);
--i;
goto NEXT_CONTOUR;
}
}
}
NEXT_CONTOUR: ;
}
}
// at this point, all loops should be in contours[0]
ExtrusionEntityCollection entities = this->_traverse_loops(contours.front(), thin_walls);
// if brim will be printed, reverse the order of perimeters so that
// we continue inwards after having finished the brim
// TODO: add test for perimeter order
if (this->config->external_perimeters_first
|| (this->layer_id == 0 && this->print_config->brim_width.value > 0))
entities.reverse();
// append perimeters for this slice as a collection
if (!entities.empty())
this->loops->append(entities);
}
// fill gaps
if (!gaps.empty()) {
/*
if (false) {
require "Slic3r/SVG.pm";
Slic3r::SVG::output(
"gaps.svg",
expolygons => union_ex(\@gaps),
);
}
*/
// where $pwidth < thickness < 2*$pspacing, infill with width = 2*$pwidth
// where 0.1*$pwidth < thickness < $pwidth, infill with width = 1*$pwidth
std::vector<PerimeterGeneratorGapSize> gap_sizes;
gap_sizes.push_back(PerimeterGeneratorGapSize(pwidth, 2*pspacing, 2*pwidth));
gap_sizes.push_back(PerimeterGeneratorGapSize(0.1*pwidth, pwidth, 1*pwidth));
for (std::vector<PerimeterGeneratorGapSize>::const_iterator gap_size = gap_sizes.begin();
gap_size != gap_sizes.end(); ++gap_size) {
ExtrusionEntityCollection gap_fill = this->_fill_gaps(gap_size->min,
gap_size->max, unscale(gap_size->width), gaps);
this->gap_fill->append(gap_fill.entities);
// Make sure we don't infill narrow parts that are already gap-filled
// (we only consider this surface's gaps to reduce the diff() complexity).
// Growing actual extrusions ensures that gaps not filled by medial axis
// are not subtracted from fill surfaces (they might be too short gaps
// that medial axis skips but infill might join with other infill regions
// and use zigzag).
coord_t dist = gap_size->width/2;
Polygons filled;
for (ExtrusionEntitiesPtr::const_iterator it = gap_fill.entities.begin();
it != gap_fill.entities.end(); ++it) {
Polygons f;
offset((*it)->as_polyline(), &f, dist);
filled.insert(filled.end(), f.begin(), f.end());
}
last = diff(last, filled);
gaps = diff(gaps, filled); // prevent more gap fill here
}
}
// create one more offset to be used as boundary for fill
// we offset by half the perimeter spacing (to get to the actual infill boundary)
// and then we offset back and forth by half the infill spacing to only consider the
// non-collapsing regions
coord_t inset = 0;
if (loop_number == 0) {
// one loop
inset += ext_pspacing2/2;
} else if (loop_number > 0) {
// two or more loops
inset += pspacing/2;
}
// only apply infill overlap if we actually have one perimeter
if (inset > 0)
inset -= this->config->get_abs_value("infill_overlap", inset + ispacing/2);
{
ExPolygons expp = union_ex(last);
// simplify infill contours according to resolution
Polygons pp;
for (ExPolygons::const_iterator ex = expp.begin(); ex != expp.end(); ++ex)
ex->simplify_p(SCALED_RESOLUTION, &pp);
// collapse too narrow infill areas
coord_t min_perimeter_infill_spacing = ispacing * (1 - INSET_OVERLAP_TOLERANCE);
expp = offset2_ex(
pp,
-inset -min_perimeter_infill_spacing/2,
+min_perimeter_infill_spacing/2
);
// append infill areas to fill_surfaces
for (ExPolygons::const_iterator ex = expp.begin(); ex != expp.end(); ++ex)
this->fill_surfaces->surfaces.push_back(Surface(stInternal, *ex)); // use a bogus surface type
}
}
}
std::string
GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
{
// get a copy; don't modify the orientation of the original loop object otherwise
// next copies (if any) would not detect the correct orientation
// extrude all loops ccw
bool was_clockwise = loop.make_counter_clockwise();
// find the point of the loop that is closest to the current extruder position
// or randomize if requested
Point last_pos = this->last_pos();
if (this->config.spiral_vase) {
loop.split_at(last_pos);
} else if (this->config.seam_position == spNearest || this->config.seam_position == spAligned) {
Polygon polygon = loop.polygon();
// simplify polygon in order to skip false positives in concave/convex detection
// (loop is always ccw as polygon.simplify() only works on ccw polygons)
Polygons simplified = polygon.simplify(scale_(EXTRUDER_CONFIG(nozzle_diameter))/2);
// restore original winding order so that concave and convex detection always happens
// on the right/outer side of the polygon
if (was_clockwise) {
for (Polygons::iterator p = simplified.begin(); p != simplified.end(); ++p)
p->reverse();
}
// concave vertices have priority
Points candidates;
for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
Points concave = p->concave_points(PI*4/3);
candidates.insert(candidates.end(), concave.begin(), concave.end());
}
// if no concave points were found, look for convex vertices
if (candidates.empty()) {
for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
Points convex = p->convex_points(PI*2/3);
candidates.insert(candidates.end(), convex.begin(), convex.end());
}
}
// retrieve the last start position for this object
if (this->layer != NULL && this->_seam_position.count(this->layer->object()) > 0) {
last_pos = this->_seam_position[this->layer->object()];
}
Point point;
if (this->config.seam_position == spNearest) {
if (candidates.empty()) candidates = polygon.points;
last_pos.nearest_point(candidates, &point);
// On 32-bit Linux, Clipper will change some point coordinates by 1 unit
// while performing simplify_polygons(), thus split_at_vertex() won't
// find them anymore.
if (!loop.split_at_vertex(point)) loop.split_at(point);
} else if (!candidates.empty()) {
Points non_overhang;
for (Points::const_iterator p = candidates.begin(); p != candidates.end(); ++p) {
if (!loop.has_overhang_point(*p))
non_overhang.push_back(*p);
}
if (!non_overhang.empty())
candidates = non_overhang;
last_pos.nearest_point(candidates, &point);
if (!loop.split_at_vertex(point)) loop.split_at(point); // see note above
} else {
if (this->config.seam_position == spAlwaysHideSeam){
if (loop.role == elrContourInternalPerimeter) {
Polygon polygon = loop.polygon();
Point centroid = polygon.centroid();
point = Point(polygon.bounding_box().max.x, centroid.y);
point.rotate(rand() % 2*PI, centroid);
}
}
}
else{
std::string
GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
{
// get a copy; don't modify the orientation of the original loop object otherwise
// next copies (if any) would not detect the correct orientation
// extrude all loops ccw
bool was_clockwise = loop.make_counter_clockwise();
SeamPosition seam_position = this->config.seam_position;
if (loop.role == elrSkirt) seam_position = spNearest;
// find the point of the loop that is closest to the current extruder position
// or randomize if requested
Point last_pos = this->last_pos();
if (this->config.spiral_vase) {
loop.split_at(last_pos);
} else if (seam_position == spNearest || seam_position == spAligned) {
const Polygon polygon = loop.polygon();
// simplify polygon in order to skip false positives in concave/convex detection
// (loop is always ccw as polygon.simplify() only works on ccw polygons)
Polygons simplified = polygon.simplify(scale_(EXTRUDER_CONFIG(nozzle_diameter))/2);
// restore original winding order so that concave and convex detection always happens
// on the right/outer side of the polygon
if (was_clockwise) {
for (Polygons::iterator p = simplified.begin(); p != simplified.end(); ++p)
p->reverse();
}
// concave vertices have priority
Points candidates;
for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
Points concave = p->concave_points(PI*4/3);
candidates.insert(candidates.end(), concave.begin(), concave.end());
}
// if no concave points were found, look for convex vertices
if (candidates.empty()) {
for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
Points convex = p->convex_points(PI*2/3);
candidates.insert(candidates.end(), convex.begin(), convex.end());
}
}
// retrieve the last start position for this object
if (this->layer != NULL && this->_seam_position.count(this->layer->object()) > 0) {
last_pos = this->_seam_position[this->layer->object()];
}
Point point;
if (seam_position == spNearest) {
if (candidates.empty()) candidates = polygon.points;
last_pos.nearest_point(candidates, &point);
// On 32-bit Linux, Clipper will change some point coordinates by 1 unit
// while performing simplify_polygons(), thus split_at_vertex() won't
// find them anymore.
if (!loop.split_at_vertex(point)) loop.split_at(point);
} else if (!candidates.empty()) {
Points non_overhang;
for (Points::const_iterator p = candidates.begin(); p != candidates.end(); ++p) {
if (!loop.has_overhang_point(*p))
non_overhang.push_back(*p);
}
if (!non_overhang.empty())
candidates = non_overhang;
last_pos.nearest_point(candidates, &point);
if (!loop.split_at_vertex(point)) loop.split_at(point); // see note above
} else {
point = last_pos.projection_onto(polygon);
loop.split_at(point);
}
if (this->layer != NULL)
this->_seam_position[this->layer->object()] = point;
} else if (seam_position == spRandom) {
if (loop.role == elrContourInternalPerimeter) {
Polygon polygon = loop.polygon();
Point centroid = polygon.centroid();
last_pos = Point(polygon.bounding_box().max.x, centroid.y);
last_pos.rotate(fmod((float)rand()/16.0, 2.0*PI), centroid);
}
loop.split_at(last_pos);
}
// clip the path to avoid the extruder to get exactly on the first point of the loop;
// if polyline was shorter than the clipping distance we'd get a null polyline, so
// we discard it in that case
double clip_length = this->enable_loop_clipping
? scale_(EXTRUDER_CONFIG(nozzle_diameter)) * LOOP_CLIPPING_LENGTH_OVER_NOZZLE_DIAMETER
: 0;
// get paths
ExtrusionPaths paths;
loop.clip_end(clip_length, &paths);
if (paths.empty()) return "";
// apply the small perimeter speed
if (paths.front().is_perimeter() && loop.length() <= SMALL_PERIMETER_LENGTH) {
if (speed == -1) speed = this->config.get_abs_value("small_perimeter_speed");
}
// extrude along the path
std::string gcode;
for (ExtrusionPaths::const_iterator path = paths.begin(); path != paths.end(); ++path)
gcode += this->_extrude(*path, description, speed);
// reset acceleration
gcode += this->writer.set_acceleration(this->config.default_acceleration.value);
if (this->wipe.enable)
this->wipe.path = paths.front().polyline; // TODO: don't limit wipe to last path
// make a little move inwards before leaving loop
if (paths.back().role == erExternalPerimeter && this->layer != NULL && this->config.perimeters > 1) {
// detect angle between last and first segment
// the side depends on the original winding order of the polygon (left for contours, right for holes)
Point a = paths.front().polyline.points[1]; // second point
Point b = *(paths.back().polyline.points.end()-3); // second to last point
if (was_clockwise) {
// swap points
Point c = a; a = b; b = c;
}
double angle = paths.front().first_point().ccw_angle(a, b) / 3;
// turn left if contour, turn right if hole
if (was_clockwise) angle *= -1;
// create the destination point along the first segment and rotate it
// we make sure we don't exceed the segment length because we don't know
// the rotation of the second segment so we might cross the object boundary
Line first_segment(
paths.front().polyline.points[0],
paths.front().polyline.points[1]
);
double distance = std::min(
scale_(EXTRUDER_CONFIG(nozzle_diameter)),
first_segment.length()
);
Point point = first_segment.point_at(distance);
point.rotate(angle, first_segment.a);
// generate the travel move
gcode += this->writer.travel_to_xy(this->point_to_gcode(point), "move inwards before travel");
}
return gcode;
}
MotionPlannerGraph*
MotionPlanner::init_graph(int island_idx)
{
if (this->graphs[island_idx + 1] == NULL) {
Polygons pp;
if (island_idx == -1) {
pp = this->outer;
} else {
pp = this->inner[island_idx];
}
MotionPlannerGraph* graph = this->graphs[island_idx + 1] = new MotionPlannerGraph();
// add polygon boundaries as edges
size_t node_idx = 0;
Lines lines;
for (Polygons::const_iterator polygon = pp.begin(); polygon != pp.end(); ++polygon) {
graph->nodes.push_back(polygon->points.back());
node_idx++;
for (Points::const_iterator p = polygon->points.begin(); p != polygon->points.end(); ++p) {
graph->nodes.push_back(*p);
double dist = graph->nodes[node_idx-1].distance_to(*p);
graph->add_edge(node_idx-1, node_idx, dist);
graph->add_edge(node_idx, node_idx-1, dist);
node_idx++;
}
polygon->lines(&lines);
}
// add Voronoi edges as internal edges
{
typedef voronoi_diagram<double> VD;
typedef std::map<const VD::vertex_type*,size_t> t_vd_vertices;
VD vd;
t_vd_vertices vd_vertices;
boost::polygon::construct_voronoi(lines.begin(), lines.end(), &vd);
for (VD::const_edge_iterator edge = vd.edges().begin(); edge != vd.edges().end(); ++edge) {
if (edge->is_infinite()) continue;
const VD::vertex_type* v0 = edge->vertex0();
const VD::vertex_type* v1 = edge->vertex1();
Point p0 = Point(v0->x(), v0->y());
Point p1 = Point(v1->x(), v1->y());
// contains() should probably be faster than contains(),
// and should it fail on any boundary points it's not a big problem
if (island_idx == -1) {
if (!this->outer.contains(p0) || !this->outer.contains(p1)) continue;
} else {
if (!this->inner[island_idx].contains(p0) || !this->inner[island_idx].contains(p1)) continue;
}
t_vd_vertices::const_iterator i_v0 = vd_vertices.find(v0);
size_t v0_idx;
if (i_v0 == vd_vertices.end()) {
graph->nodes.push_back(p0);
v0_idx = node_idx;
vd_vertices[v0] = node_idx;
node_idx++;
} else {
v0_idx = i_v0->second;
}
t_vd_vertices::const_iterator i_v1 = vd_vertices.find(v1);
size_t v1_idx;
if (i_v1 == vd_vertices.end()) {
graph->nodes.push_back(p1);
v1_idx = node_idx;
vd_vertices[v1] = node_idx;
node_idx++;
} else {
v1_idx = i_v1->second;
}
double dist = graph->nodes[v0_idx].distance_to(graph->nodes[v1_idx]);
graph->add_edge(v0_idx, v1_idx, dist);
}
}
return graph;
}
return this->graphs[island_idx + 1];
}
bool
BridgeDetector::detect_angle()
{
if (this->_edges.empty() || this->_anchors.empty()) return false;
/* Outset the bridge expolygon by half the amount we used for detecting anchors;
we'll use this one to clip our test lines and be sure that their endpoints
are inside the anchors and not on their contours leading to false negatives. */
Polygons clip_area;
offset(this->expolygon, &clip_area, +this->extrusion_width/2);
/* we'll now try several directions using a rudimentary visibility check:
bridge in several directions and then sum the length of lines having both
endpoints within anchors */
// we test angles according to configured resolution
std::vector<double> angles;
for (int i = 0; i <= PI/this->resolution; ++i)
angles.push_back(i * this->resolution);
// we also test angles of each bridge contour
{
Polygons pp = this->expolygon;
for (Polygons::const_iterator p = pp.begin(); p != pp.end(); ++p) {
Lines lines = p->lines();
for (Lines::const_iterator line = lines.begin(); line != lines.end(); ++line)
angles.push_back(line->direction());
}
}
/* we also test angles of each open supporting edge
(this finds the optimal angle for C-shaped supports) */
for (Polylines::const_iterator edge = this->_edges.begin(); edge != this->_edges.end(); ++edge) {
if (edge->first_point().coincides_with(edge->last_point())) continue;
angles.push_back(Line(edge->first_point(), edge->last_point()).direction());
}
// remove duplicates
double min_resolution = PI/180.0; // 1 degree
std::sort(angles.begin(), angles.end());
for (size_t i = 1; i < angles.size(); ++i) {
if (xd::Geometry::directions_parallel(angles[i], angles[i-1], min_resolution)) {
angles.erase(angles.begin() + i);
--i;
}
}
/* compare first value with last one and remove the greatest one (PI)
in case they are parallel (PI, 0) */
if (xd::Geometry::directions_parallel(angles.front(), angles.back(), min_resolution))
angles.pop_back();
BridgeDirectionComparator bdcomp(this->extrusion_width);
double line_increment = this->extrusion_width;
bool have_coverage = false;
for (std::vector<double>::const_iterator angle = angles.begin(); angle != angles.end(); ++angle) {
Polygons my_clip_area = clip_area;
ExPolygons my_anchors = this->_anchors;
// rotate everything - the center point doesn't matter
for (Polygons::iterator it = my_clip_area.begin(); it != my_clip_area.end(); ++it)
it->rotate(-*angle, Point(0,0));
for (ExPolygons::iterator it = my_anchors.begin(); it != my_anchors.end(); ++it)
it->rotate(-*angle, Point(0,0));
// generate lines in this direction
BoundingBox bb;
for (ExPolygons::const_iterator it = my_anchors.begin(); it != my_anchors.end(); ++it)
bb.merge((Points)*it);
Lines lines;
for (coord_t y = bb.min.y; y <= bb.max.y; y += line_increment)
lines.push_back(Line(Point(bb.min.x, y), Point(bb.max.x, y)));
Lines clipped_lines;
intersection(lines, my_clip_area, &clipped_lines);
// remove any line not having both endpoints within anchors
for (size_t i = 0; i < clipped_lines.size(); ++i) {
Line &line = clipped_lines[i];
if (!xd::Geometry::contains(my_anchors, line.a)
|| !xd::Geometry::contains(my_anchors, line.b)) {
clipped_lines.erase(clipped_lines.begin() + i);
--i;
}
}
std::vector<double> lengths;
double total_length = 0;
for (Lines::const_iterator line = clipped_lines.begin(); line != clipped_lines.end(); ++line) {
double len = line->length();
lengths.push_back(len);
total_length += len;
}
if (total_length) have_coverage = true;
// sum length of bridged lines
bdcomp.dir_coverage[*angle] = total_length;
/* The following produces more correct results in some cases and more broken in others.
TODO: investigate, as it looks more reliable than line clipping. */
// $directions_coverage{$angle} = sum(map $_->area, @{$self->coverage($angle)}) // 0;
// max length of bridged lines
bdcomp.dir_avg_length[*angle] = !lengths.empty()
? *std::max_element(lengths.begin(), lengths.end())
: 0;
}
// if no direction produced coverage, then there's no bridge direction
if (!have_coverage) return false;
// sort directions by score
std::sort(angles.begin(), angles.end(), bdcomp);
this->angle = angles.front();
if (this->angle >= PI) this->angle -= PI;
// #ifdef SLIC3R_DEBUG
// printf(" Optimal infill angle is %d degrees\n", (int)Slic3r::Geometry::rad2deg(this->angle));
// #endif
return true;
}
void
BridgeDetector::coverage(double angle, Polygons* coverage) const
{
// Clone our expolygon and rotate it so that we work with vertical lines.
ExPolygon expolygon = this->expolygon;
expolygon.rotate(PI/2.0 - angle, Point(0,0));
/* Outset the bridge expolygon by half the amount we used for detecting anchors;
we'll use this one to generate our trapezoids and be sure that their vertices
are inside the anchors and not on their contours leading to false negatives. */
ExPolygons grown;
offset(expolygon, &grown, this->extrusion_width/2.0);
// Compute trapezoids according to a vertical orientation
Polygons trapezoids;
for (ExPolygons::const_iterator it = grown.begin(); it != grown.end(); ++it)
it->get_trapezoids2(&trapezoids, PI/2.0);
// get anchors, convert them to Polygons and rotate them too
Polygons anchors;
for (ExPolygons::const_iterator anchor = this->_anchors.begin(); anchor != this->_anchors.end(); ++anchor) {
Polygons pp = *anchor;
for (Polygons::iterator p = pp.begin(); p != pp.end(); ++p)
p->rotate(PI/2.0 - angle, Point(0,0));
anchors.insert(anchors.end(), pp.begin(), pp.end());
}
Polygons covered;
for (Polygons::const_iterator trapezoid = trapezoids.begin(); trapezoid != trapezoids.end(); ++trapezoid) {
Lines lines = trapezoid->lines();
Lines supported;
intersection(lines, anchors, &supported);
// not nice, we need a more robust non-numeric check
for (size_t i = 0; i < supported.size(); ++i) {
if (supported[i].length() < this->extrusion_width) {
supported.erase(supported.begin() + i);
i--;
}
}
if (supported.size() >= 2) covered.push_back(*trapezoid);
}
// merge trapezoids and rotate them back
Polygons _coverage;
union_(covered, &_coverage);
for (Polygons::iterator p = _coverage.begin(); p != _coverage.end(); ++p)
p->rotate(-(PI/2.0 - angle), Point(0,0));
// intersect trapezoids with actual bridge area to remove extra margins
// and append it to result
intersection(_coverage, this->expolygon, coverage);
/*
if (0) {
my @lines = map @{$_->lines}, @$trapezoids;
$_->rotate(-(PI/2 - $angle), [0,0]) for @lines;
require "Slic3r/SVG.pm";
Slic3r::SVG::output(
"coverage_" . rad2deg($angle) . ".svg",
expolygons => [$self->expolygon],
green_expolygons => $self->_anchors,
red_expolygons => $coverage,
lines => \@lines,
);
}
*/
}
void
SLAPrint::slice()
{
TriangleMesh mesh = this->model->mesh();
mesh.repair();
// align to origin taking raft into account
this->bb = mesh.bounding_box();
if (this->config.raft_layers > 0) {
this->bb.min.x -= this->config.raft_offset.value;
this->bb.min.y -= this->config.raft_offset.value;
this->bb.max.x += this->config.raft_offset.value;
this->bb.max.y += this->config.raft_offset.value;
}
mesh.translate(0, 0, -bb.min.z);
this->bb.translate(0, 0, -bb.min.z);
// if we are generating a raft, first_layer_height will not affect mesh slicing
const float lh = this->config.layer_height.value;
const float first_lh = this->config.first_layer_height.value;
// generate the list of Z coordinates for mesh slicing
// (we slice each layer at half of its thickness)
this->layers.clear();
{
const float first_slice_lh = (this->config.raft_layers > 0) ? lh : first_lh;
this->layers.push_back(Layer(first_slice_lh/2, first_slice_lh));
}
while (this->layers.back().print_z + lh/2 <= mesh.stl.stats.max.z) {
this->layers.push_back(Layer(this->layers.back().print_z + lh/2, this->layers.back().print_z + lh));
}
// perform slicing and generate layers
{
std::vector<float> slice_z;
for (size_t i = 0; i < this->layers.size(); ++i)
slice_z.push_back(this->layers[i].slice_z);
std::vector<ExPolygons> slices;
TriangleMeshSlicer(&mesh).slice(slice_z, &slices);
for (size_t i = 0; i < slices.size(); ++i)
this->layers[i].slices.expolygons = slices[i];
}
// generate infill
if (this->config.fill_density < 100) {
std::auto_ptr<Fill> fill(Fill::new_from_type(this->config.fill_pattern.value));
fill->bounding_box.merge(Point::new_scale(bb.min.x, bb.min.y));
fill->bounding_box.merge(Point::new_scale(bb.max.x, bb.max.y));
fill->spacing = this->config.get_abs_value("infill_extrusion_width", this->config.layer_height.value);
fill->angle = Geometry::deg2rad(this->config.fill_angle.value);
fill->density = this->config.fill_density.value/100;
parallelize<size_t>(
0,
this->layers.size()-1,
boost::bind(&SLAPrint::_infill_layer, this, _1, fill.get()),
this->config.threads.value
);
}
// generate support material
this->sm_pillars.clear();
ExPolygons overhangs;
if (this->config.support_material) {
// flatten and merge all the overhangs
{
Polygons pp;
for (std::vector<Layer>::const_iterator it = this->layers.begin()+1; it != this->layers.end(); ++it)
pp += diff(it->slices, (it - 1)->slices);
overhangs = union_ex(pp);
}
// generate points following the shape of each island
Points pillars_pos;
const coordf_t spacing = scale_(this->config.support_material_spacing);
const coordf_t radius = scale_(this->sm_pillars_radius());
for (ExPolygons::const_iterator it = overhangs.begin(); it != overhangs.end(); ++it) {
// leave a radius/2 gap between pillars and contour to prevent lateral adhesion
for (float inset = radius * 1.5;; inset += spacing) {
// inset according to the configured spacing
Polygons curr = offset(*it, -inset);
if (curr.empty()) break;
// generate points along the contours
for (Polygons::const_iterator pg = curr.begin(); pg != curr.end(); ++pg) {
Points pp = pg->equally_spaced_points(spacing);
for (Points::const_iterator p = pp.begin(); p != pp.end(); ++p)
pillars_pos.push_back(*p);
}
}
}
// for each pillar, check which layers it applies to
for (Points::const_iterator p = pillars_pos.begin(); p != pillars_pos.end(); ++p) {
SupportPillar pillar(*p);
bool object_hit = false;
// check layers top-down
for (int i = this->layers.size()-1; i >= 0; --i) {
// check whether point is void in this layer
if (!this->layers[i].slices.contains(*p)) {
// no slice contains the point, so it's in the void
if (pillar.top_layer > 0) {
// we have a pillar, so extend it
pillar.bottom_layer = i + this->config.raft_layers;
} else if (object_hit) {
// we don't have a pillar and we're below the object, so create one
pillar.top_layer = i + this->config.raft_layers;
}
} else {
if (pillar.top_layer > 0) {
// we have a pillar which is not needed anymore, so store it and initialize a new potential pillar
this->sm_pillars.push_back(pillar);
pillar = SupportPillar(*p);
}
object_hit = true;
}
}
if (pillar.top_layer > 0) this->sm_pillars.push_back(pillar);
}
}
// generate a solid raft if requested
// (do this after support material because we take support material shape into account)
if (this->config.raft_layers > 0) {
ExPolygons raft = this->layers.front().slices + overhangs; // take support material into account
raft = offset_ex(raft, scale_(this->config.raft_offset));
for (int i = this->config.raft_layers; i >= 1; --i) {
this->layers.insert(this->layers.begin(), Layer(0, first_lh + lh * (i-1)));
this->layers.front().slices = raft;
}
// prepend total raft height to all sliced layers
for (size_t i = this->config.raft_layers; i < this->layers.size(); ++i)
this->layers[i].print_z += first_lh + lh * (this->config.raft_layers-1);
}
}
