https://github.com/maplibre/geometry.hpp

C++ geometry types
https://github.com/maplibre/geometry.hpp

Last synced: 5 days ago
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C++ geometry types

• Host: GitHub
• URL: https://github.com/maplibre/geometry.hpp
• Owner: maplibre
• License: isc
• Created: 2024-10-14T23:15:46.000Z (29 days ago)
• Default Branch: main
• Last Pushed: 2024-10-21T22:18:59.000Z (22 days ago)
• Last Synced: 2024-11-04T12:27:08.480Z (9 days ago)
• Language: C++
• Homepage:
• Size: 150 KB
• Stars: 1
• Watchers: 3
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Funding: .github/FUNDING.yml
  • License: LICENSE
  • Code of conduct: CODE-OF-CONDUCT.md
  • Security: SECURITY.md

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# geometry.hpp

Provides header-only, generic C++ interfaces for geometry types, geometry collections, and features.

 - `maplibre::geometry::point`

 - `maplibre::geometry::multi_point`

 - `maplibre::geometry::line_string`

 - `maplibre::geometry::multi_line_string`

 - `maplibre::geometry::polygon`

 - `maplibre::geometry::multi_polygon`

 - `maplibre::geometry::geometry_collection`

 - `maplibre::feature::feature`

Dependency of [MapLibre Native](https://github.com/maplibre/maplibre-native).

### Design

These types are designed to be easy to parse and serialize to [GeoJSON](http://geojson.org/).

They should also be a robust and high performance container for data processing and conversion.

### Goals

 - Header-only

 - Fast compile

 - C++20

 - No external dependencies for usage of core types (point, line_string, etc)

 - No dependencies for usage of enclosing `geometry` type

 - Easily [adaptable to `boost::geometry`](http://www.boost.org/doc/libs/1_56_0/libs/geometry/doc/html/geometry/examples/example__adapting_a_legacy_geometry_object_model.html)

### Usage

Using a single type directly:

```cpp

#include 

#include 

using maplibre::geometry::point;

int main() {

    point pt(1.0,0.0);

    std::clog << "x: " << pt.x << " y: " << pt.y << "\n";

}

```

Creating a geometry collection:

```cpp

#include 

#include 

#include 

using maplibre::geometry::geometry_collection;

using maplibre::geometry::geometry;

using maplibre::geometry::point;

using point_type = point;

struct printer

{

    printer() {}

    void operator()(point_type const& pt) const

    {

        std::clog << "x: " << pt.x << " y: " << pt.y << "\n";

    }

    template 

    void operator()(T const& g) const

    {

        std::clog << "encountered non-point geometry\n";

    }

};

int main() {

    geometry_collection gc;

    gc.emplace_back(point_type(1.0,0.0));

    geometry const& geom = gc.at(0);

    printer visitor;

    std::visit(visitor, geom);

}

```