The aim of geom3d library is to handle and visualize 3D geometric primitives such as points, lines, planes, polyhedra... It provides lowlevel functions for manipulating 3D geometric primitives, making easier the development of more complex geometric algorithms.
Some features of the library are:
 creation of various shapes (3D points, 3D lines, planes, polyhedra...) through an intuitive syntax. Ex:
createPlane(p1, p2, p3) to create a plane through 3 points.
 derivation of new shapes: intersection between 2 planes, intersection between a plane and a line, between a sphere and a line...
 functions for 3D polygons and polyhedra. Polyhedra use classical vertexfaces arrays (face array contain indices of vertices), and support faces with any number of vertices. Some basic models are provided (createOctaedron, createCubeoctaedron...), as well as some computation (like faceNormal or centroid)
 manipulation of planar transformation. Ex.:
ROT = createRotationOx(THETA);
P2 = transformPoint3d(P1, ROT);
 direct drawing of shapes with specialized functions. Clipping is performed automatically for unbounded shapes such as lines or rays. Ex:
drawPoint3d([50 50 25; 20 70 10], 'ro'); % draw some points
drawLine3d([X0 Y0 Z0 DX DY DZ]); % clip and draw straight line
The library is divided into two packages:
* geom3d for general computation in 3d
* meshes3d for representation and manipulation of polyhedral meshes
Several functions require the geom2d package, available on the FEx.
Additional help is provided in geom3d/Contents.m and meshes3d/Contents.m files, as well as summary files like 'points3d.m' or 'lines3d.m'.
