GenericMapItems Concept Reference

Definition

The concept GenericMapItems allows to customize a dD generic map by choosing the information associated with darts, by enabling and disabling some attributes, and by choosing to use indices or handles. For that, it defines an inner class template named Dart_wrapper, with one template parameter, Map, a model of the GenericMap concept. This inner class can define the two types Dart_info and Attributes.

Has Models:

CGAL::Generic_map_min_items

See also

GenericMap

Example

The following examples show two possible models of the GenericMapItems concept: the first one for a generic map without dart information, nor enabled attributes, the second one for a generic map that uses std::uint16_t as indices, with a double associated with each dart, and edge attributes enabled, and associated with a Cell_attribute containing an int.

struct Exemple_Item_1
{
  template < class CMap >
  struct Dart_wrapper
  {};
};
 
struct Exemple_Item_2
{
  typedef CGAL::Tag_true Use_index; // CGAL::Tag_false by default
  typedef std::uint16_t Index_type; // std::uint32_t by default
  template < class GMap >
  struct Dart_wrapper
  {
    typedef double Dart_info;
    typedef CGAL::Cell_attribute<GMap, int> Edge_attrib;
    typedef std::tuple<void,Edge_attrib> Attributes;
  };
};

Public Types
typedef unspecified_type	Use_index
	If Use_index is CGAL::Tag_true, uses indices as descriptors.
typedef unspecified_type	Index_type
	Number type used for indices when Use_index is CGAL::Tag_true.
template<typename Map >
using	Dart_wrapper = unspecified_type
	Wrapper class defining type of information associated with darts and types of attributes.

Member Typedef Documentation

Dart_wrapper

template<typename Map >

using GenericMapItems::Dart_wrapper = unspecified_type

Wrapper class defining type of information associated with darts and types of attributes.

The class Dart_wrapper<Map> must provide:

• Dart_wrapper<Map>::Dart_info, the type of information associated with darts. Not defined or equal to void to have no information.
• Dart_wrapper<Map>::Attributes The tuple of attributes, containing at most Map::dimension+1 types (one for each possible cell of the generic map). Each type of the tuple must be either a model of the CellAttribute concept or void. The first type corresponds to 0-attributes, the second to 1-attributes and so on. If the \( i^{\mbox{th}}\) type in the tuple is void, (i-1)-attributes are disabled. Otherwise, (i-1)-attributes are enabled and have the given type. If the size of the tuple is k, with k<Map::dimension+1, \( \forall\)i: k \( \leq\)i \( \leq\)Map::dimension, i-attributes are disabled. If this type is not defined, all attributes are disabled.

Note

It can be implemented using a nested template class.

Index_type

typedef unspecified_type GenericMapItems::Index_type

Number type used for indices when Use_index is CGAL::Tag_true.

By default, use std::uint32_t.

Use_index

typedef unspecified_type GenericMapItems::Use_index

If Use_index is CGAL::Tag_true, uses indices as descriptors.

Otherwise (if this type is not defined or different from CGAL::Tag_true), use handles.