View source for Lib2geom


== What is lib2geom? ==

[https://gitlab.com/inkscape/lib2geom lib2geom] (2Geom in private life) was initially a library developed for Inkscape, but it can provide a robust computational geometry framework for any application. It is not a rendering library, instead concentrating on high level algorithms such as computing arc length.

== Design Decisions ==
* Small, algebraic objects (Point/Matrix) will be mutable, whereas large objects like a pathset will be immutable.  <justification here>
* We are using an original development method we've dubbed "Toy Driven Development".  Under this process graphical toys are implemented which allow playing with the features of the library.

== Quick Feature List ==

(not complete)

* C++
* Functional programming style.
* Points
* Efficient affine transformations
* Rectangles
* Convex Hulls
* Bounded error
* General purpose paths:
** Exact elliptical arcs
** Area
** Centroid and bending moments
* Path Locations:
** Determination of special spots (e.g. maximum curvature)
** Splitting
** Point, tangent, curvature at location
** Efficient arc length and inverse arc length
* Path algebra:
** Computations such as offset curves can be written with their mathematical definition and still get a bounded error, efficient curve. (preliminary trials indicate offset done this way out performs the method used in Inkscape)
* Arbitrary distortion (with bounded error):
** Mesh distorts
** Computational distorts such as the GIMP's 'vortex' plugin
** 3d mapping (perspective, flag, sphere)
* Exact boolean ops (elliptic arcs remain elliptic arcs)
* Efficient 2d database
* Implicit function plotting
* NURBs input and output
* Tunable path simplification
* PDoF constraint system for CAD/CAGD



== Links ==

[[WorkingWith2GeomFAQ]]: real-life questions answered about using <code>2Geom</code> in real code

[[lib2geom py2geom]]: Python bindings to <code>2geom</code>. With this you can use the power of <code>2geom</code> in Python scripts.

https://sourceforge.net/p/lib2geom/wiki: 2geom wiki site on SourceForge (obsolescent)

https://gitlab.com/inkscape/lib2geom/: Official source code for the project