libnest2d::placers::NfpPConfig< RawShape > Struct Template Reference

#include <src/libnest2d/include/libnest2d/placers/nfpplacer.hpp>

Collaboration diagram for libnest2d::placers::NfpPConfig< RawShape >:

Public Types
enum class	Alignment {   CENTER , BOTTOM_LEFT , BOTTOM_RIGHT , TOP_LEFT ,   TOP_RIGHT , DONT_ALIGN }
using	ItemGroup = _ItemGroup< RawShape >

Public Member Functions
	NfpPConfig ()

Public Attributes
std::vector< Radians >	rotations
	Which angles to try out for better results.
Alignment	alignment
	Where to align the resulting packed pile.
Alignment	starting_point
	Where to start putting objects in the bin.
std::function< double(const _Item< RawShape > &)>	object_function
	A function object representing the fitting function in the placement optimization process. (Optional)
float	accuracy = 0.65f
	The quality of search for an optimal placement. This is a compromise slider between quality and speed. Zero is the fast and poor solution while 1.0 is the slowest but most accurate.
bool	explore_holes = false
	If you want to see items inside other item's holes, you have to turn this switch on.
bool	parallel = true
	If true, use all CPUs available. Run on a single core otherwise.
std::function< void(const nfp::Shapes< RawShape > &, const ItemGroup &, const ItemGroup &)>	before_packing
	before_packing Callback that is called just before a search for a new item's position is started. You can use this to create various cache structures and update them between subsequent packings.
std::function< void(const ItemGroup &, NfpPConfig &config)>	on_preload

Detailed Description

template<class RawShape>
struct libnest2d::placers::NfpPConfig< RawShape >

Member Typedef Documentation

ItemGroup

template<class RawShape >

using libnest2d::placers::NfpPConfig< RawShape >::ItemGroup = _ItemGroup<RawShape>

Member Enumeration Documentation

Alignment

template<class RawShape >

enum class libnest2d::placers::NfpPConfig::Alignment

strong

Enumerator
CENTER
BOTTOM_LEFT
BOTTOM_RIGHT
TOP_LEFT
TOP_RIGHT
DONT_ALIGN	‍Warning: parts may end up outside the bin with the default object function.

                         {
        CENTER,
        BOTTOM_LEFT,
        BOTTOM_RIGHT,
        TOP_LEFT,
        TOP_RIGHT,
        DONT_ALIGN      
    };

Constructor & Destructor Documentation

NfpPConfig()

template<class RawShape >

libnest2d::placers::NfpPConfig< RawShape >::NfpPConfig ( )

inline

                : rotations({0.0, Pi/2.0, Pi, 3*Pi/2}),
        alignment(Alignment::CENTER), starting_point(Alignment::CENTER) {}

References libnest2d::Pi.

Member Data Documentation

accuracy

template<class RawShape >

float libnest2d::placers::NfpPConfig< RawShape >::accuracy = 0.65f

The quality of search for an optimal placement. This is a compromise slider between quality and speed. Zero is the fast and poor solution while 1.0 is the slowest but most accurate.

alignment

template<class RawShape >

Alignment libnest2d::placers::NfpPConfig< RawShape >::alignment

Where to align the resulting packed pile.

before_packing

template<class RawShape >

std::function<void(const nfp::Shapes<RawShape>&, const ItemGroup&, const ItemGroup& )> libnest2d::placers::NfpPConfig< RawShape >::before_packing

before_packing Callback that is called just before a search for a new item's position is started. You can use this to create various cache structures and update them between subsequent packings.

Parameters

merged	pile A polygon that is the union of all items in the bin.
pile	The items parameter is a container with all the placed polygons excluding the current candidate. You can for instance check the alignment with the candidate item or do anything else.
remaining	A container with the remaining items waiting to be placed. You can use some features about the remaining items to alter to score of the current placement. If you know that you have to leave place for other items as well, that might influence your decision about where the current candidate should be placed. E.g. imagine three big circles which you want to place into a box: you might place them in a triangle shape which has the maximum pack density. But if there is a 4th big circle than you won't be able to pack it. If you knew apriori that there four circles are to be placed, you would have placed the first 3 into an L shape. This parameter can be used to make these kind of decisions (for you or a more intelligent AI).

explore_holes

template<class RawShape >

bool libnest2d::placers::NfpPConfig< RawShape >::explore_holes = false

If you want to see items inside other item's holes, you have to turn this switch on.

This will only work if a suitable nfp implementation is provided. The library has no such implementation right now.

object_function

template<class RawShape >

std::function<double(const _Item<RawShape>&)> libnest2d::placers::NfpPConfig< RawShape >::object_function

A function object representing the fitting function in the placement optimization process. (Optional)

This is the most versatile tool to configure the placer. The fitting function is evaluated many times when a new item is being placed into the bin. The output should be a rated score of the new item's position.

This is not a mandatory option as there is a default fitting function that will optimize for the best pack efficiency. With a custom fitting function you can e.g. influence the shape of the arranged pile.

Parameters

item	The only parameter is the candidate item which has info about its current position. Your job is to rate this position compared to the already packed items.

on_preload

template<class RawShape >

std::function<void(const ItemGroup &, NfpPConfig &config)> libnest2d::placers::NfpPConfig< RawShape >::on_preload

parallel

template<class RawShape >

bool libnest2d::placers::NfpPConfig< RawShape >::parallel = true

If true, use all CPUs available. Run on a single core otherwise.

rotations

template<class RawShape >

std::vector<Radians> libnest2d::placers::NfpPConfig< RawShape >::rotations

Which angles to try out for better results.

starting_point

template<class RawShape >

Alignment libnest2d::placers::NfpPConfig< RawShape >::starting_point

Where to start putting objects in the bin.

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The documentation for this struct was generated from the following file:

• src/libnest2d/include/libnest2d/placers/nfpplacer.hpp