New object function considering item size categories (big and small)

This commit is contained in:
tamasmeszaros 2018-07-27 17:31:30 +02:00
parent 84f97e1f64
commit f364bd1884
2 changed files with 91 additions and 34 deletions

View file

@ -78,7 +78,7 @@ struct NfpPConfig {
* into the bin.
*
*/
std::function<double(const Nfp::Shapes<RawShape>&, const _Item<RawShape>&,
std::function<double(Nfp::Shapes<RawShape>&, const _Item<RawShape>&,
double, double, double)>
object_function;
@ -163,18 +163,22 @@ template<class RawShape> class EdgeCache {
void fetchCorners() const {
if(!contour_.corners.empty()) return;
// TODO Accuracy
contour_.corners = contour_.distances;
for(auto& d : contour_.corners) d /= contour_.full_distance;
contour_.corners.reserve(contour_.distances.size() / 3 + 1);
for(size_t i = 0; i < contour_.distances.size() - 1; i += 3) {
contour_.corners.emplace_back(
contour_.distances.at(i) / contour_.full_distance);
}
}
void fetchHoleCorners(unsigned hidx) const {
auto& hc = holes_[hidx];
if(!hc.corners.empty()) return;
// TODO Accuracy
hc.corners = hc.distances;
for(auto& d : hc.corners) d /= hc.full_distance;
hc.corners.reserve(hc.distances.size() / 3 + 1);
for(size_t i = 0; i < hc.distances.size() - 1; i += 3) {
hc.corners.emplace_back(
hc.distances.at(i) / hc.full_distance);
}
}
inline Vertex coords(const ContourCache& cache, double distance) const {
@ -433,7 +437,7 @@ class _NofitPolyPlacer: public PlacerBoilerplate<_NofitPolyPlacer<RawShape>,
public:
using Pile = const Nfp::Shapes<RawShape>&;
using Pile = Nfp::Shapes<RawShape>;
inline explicit _NofitPolyPlacer(const BinType& bin):
Base(bin),
@ -536,7 +540,7 @@ public:
// customizable by the library client
auto _objfunc = config_.object_function?
config_.object_function :
[this](const Nfp::Shapes<RawShape>& pile, Item,
[this](Nfp::Shapes<RawShape>& pile, Item,
double occupied_area, double /*norm*/,
double penality)
{
@ -565,14 +569,14 @@ public:
d += startpos;
item.translation(d);
pile.emplace_back(item.transformedShape());
// pile.emplace_back(item.transformedShape());
double occupied_area = pile_area + item.area();
double score = _objfunc(pile, item, occupied_area,
norm_, penality_);
pile.pop_back();
// pile.pop_back();
return score;
};

View file

@ -529,7 +529,6 @@ bool arrange(Model &model, coordf_t dist, const Slic3r::BoundingBoxf* bb,
// handle different rotations
// arranger.useMinimumBoundigBoxRotation();
pcfg.rotations = { 0.0 };
double norm_2 = std::nan("");
// Magic: we will specify what is the goal of arrangement... In this case
// we override the default object function to make the larger items go into
@ -538,8 +537,8 @@ bool arrange(Model &model, coordf_t dist, const Slic3r::BoundingBoxf* bb,
// We alse sacrafice a bit of pack efficiency for this to work. As a side
// effect, the arrange procedure is a lot faster (we do not need to
// calculate the convex hulls)
pcfg.object_function = [bin, hasbin, &norm_2](
NfpPlacer::Pile pile, // The currently arranged pile
pcfg.object_function = [bin, hasbin](
NfpPlacer::Pile& pile, // The currently arranged pile
Item item,
double /*area*/, // Sum area of items (not needed)
double norm, // A norming factor for physical dimensions
@ -547,37 +546,91 @@ bool arrange(Model &model, coordf_t dist, const Slic3r::BoundingBoxf* bb,
{
using pl = PointLike;
auto bb = ShapeLike::boundingBox(pile);
static const double BIG_ITEM_TRESHOLD = 0.2;
static const double GRAVITY_RATIO = 0.5;
static const double DENSITY_RATIO = 1.0 - GRAVITY_RATIO;
// We will treat big items (compared to the print bed) differently
NfpPlacer::Pile bigs;
bigs.reserve(pile.size());
for(auto& p : pile) {
auto pbb = ShapeLike::boundingBox(p);
auto na = std::sqrt(pbb.width()*pbb.height())/norm;
if(na > BIG_ITEM_TRESHOLD) bigs.emplace_back(p);
}
// Candidate item bounding box
auto ibb = item.boundingBox();
auto minc = ibb.minCorner();
auto maxc = ibb.maxCorner();
if(std::isnan(norm_2)) norm_2 = pow(norm, 2);
// Calculate the full bounding box of the pile with the candidate item
pile.emplace_back(item.transformedShape());
auto fullbb = ShapeLike::boundingBox(pile);
pile.pop_back();
// We get the distance of the reference point from the center of the
// heat bed
auto cc = bb.center();
auto top_left = PointImpl{getX(minc), getY(maxc)};
auto bottom_right = PointImpl{getX(maxc), getY(minc)};
// The bounding box of the big items (they will accumulate in the center
// of the pile
auto bigbb = bigs.empty()? fullbb : ShapeLike::boundingBox(bigs);
auto a = pl::distance(ibb.maxCorner(), cc);
auto b = pl::distance(ibb.minCorner(), cc);
auto c = pl::distance(ibb.center(), cc);
auto d = pl::distance(top_left, cc);
auto e = pl::distance(bottom_right, cc);
// The size indicator of the candidate item. This is not the area,
// but almost...
auto itemnormarea = std::sqrt(ibb.width()*ibb.height())/norm;
auto area = bb.width() * bb.height() / norm_2;
// Will hold the resulting score
double score = 0;
auto min_dist = std::min({a, b, c, d, e}) / norm;
if(itemnormarea > BIG_ITEM_TRESHOLD) {
// This branch is for the bigger items..
// Here we will use the closest point of the item bounding box to
// the already arranged pile. So not the bb center nor the a choosen
// corner but whichever is the closest to the center. This will
// prevent unwanted strange arrangements.
// The score will be the normalized distance which will be minimized,
// effectively creating a circle shaped pile of items
double score = 0.8*min_dist + 0.2*area;
auto minc = ibb.minCorner(); // bottom left corner
auto maxc = ibb.maxCorner(); // top right corner
// top left and bottom right corners
auto top_left = PointImpl{getX(minc), getY(maxc)};
auto bottom_right = PointImpl{getX(maxc), getY(minc)};
auto cc = fullbb.center(); // The gravity center
// Now the distnce of the gravity center will be calculated to the
// five anchor points and the smallest will be chosen.
std::array<double, 5> dists;
dists[0] = pl::distance(minc, cc);
dists[1] = pl::distance(maxc, cc);
dists[2] = pl::distance(ibb.center(), cc);
dists[3] = pl::distance(top_left, cc);
dists[4] = pl::distance(bottom_right, cc);
auto dist = *(std::min_element(dists.begin(), dists.end())) / norm;
// Density is the pack density: how big is the arranged pile
auto density = std::sqrt(fullbb.width()*fullbb.height()) / norm;
// The score is a weighted sum of the distance from pile center
// and the pile size
score = GRAVITY_RATIO * dist + DENSITY_RATIO * density;
std::cout << "big " << std::endl;
} else if(itemnormarea < BIG_ITEM_TRESHOLD && bigs.empty()) {
// If there are no big items, only small, we should consider the
// density here as well to not get silly results
auto bindist = pl::distance(ibb.center(), bin.center()) / norm;
auto density = std::sqrt(fullbb.width()*fullbb.height()) / norm;
score = GRAVITY_RATIO* bindist + DENSITY_RATIO * density;
} else {
// Here there are the small items that should be placed around the
// already processed bigger items.
// No need to play around with the anchor points, the center will be
// just fine for small items
score = pl::distance(ibb.center(), bigbb.center()) / norm;
}
// If it does not fit into the print bed we will beat it
// with a large penality. If we would not do this, there would be only
// one big pile that doesn't care whether it fits onto the print bed.
if(!NfpPlacer::wouldFit(bb, bin)) score = 2*penality - score;
if(!NfpPlacer::wouldFit(fullbb, bin)) score = 2*penality - score;
return score;
};