YYAST

YYAST is a library which completes Lex and Yacc by adding an Abstract Syntax Tree (AST). It is designed so that you write as little as code as possible in the Lex and Yacc grammar files, so that it doesn't distract from the grammar of the language.

YYAST was intended to create a stand alone parser for your new programming language. The AST files created by the stand alone parser can the be read by your compiler which can be written in a high level programming language.

Distribution is allowed under the BSD 2-Clause license.

libtvutils

Take Vos' Library of useful utilities.

A C library of types and function that don't belong in their own library. The functions are designed primarily with performance in mind. These are a few of the functions in this library:

intel aes
atomic
base64
large integer math
binary search
daemonizing
dynamic argument passing
hash table
endian and unaligned memory access
random number generator access
lock-free ring buffer
strings
time

Distribution is allowed under the LGPL 2.1+ License.

GitHub page

CAMVOX

CAMVOX is a 3D CSG (Constructive Solid Geometry) / Voxel engine. It was originally designed to be used for a CAM (Computer Aided Manufacturing).

Currently it supports just a few shapes and most operations, these can be combined to form more complex shapes:

Cylinder
Plane
Sphere
Difference
Invert
Union
Intersection

Distribution is allowed under the GPL 3+ License.