3d math library for C. Vectors, 3x3 matrices, quaternions. 32-bit floats.
This library is intended for embedded projects where C++ is not used. In the author's opinion, C++'s feature set enables dramatically more readable 3d math code. However, many embedded projects stick with C by necessity or preference. The goal of this project is to create the best possible programmer experience within the constraints of C syntax. If cmath3d is missing something you need, feature requests are encouraged.
Unlike many other C libraries of this type,
cmath3d passes arguments
and returns results by value instead of by pointer and pointer-to-output.
This choice has several motivations:
- avoids the need to name non-meaningful intermediate results for the sake of taking their address
- enables nested expressions
- reduces bugs by allowing more variables to be declared
- gives the optimizing compiler complete knowledge about function semantics, theoretically enabling better optimizations (see Chandler Carruth's talk)
Although Carruth's talk implies that using these functions with inline, header-only definitions -- thus hiding no code from the compiler in external object files -- will enable as good or better optimizations than a pass-by-pointer version, in practice this library seems to consume more stack memory than it should. I am currently researching ways to fix this problem, since I believe a SSA compiler with the ability to destructure structs should produce optimal code from this library.
note for users
If you use
cmath3d in your project,
I would very much appreciate it if you leave a comment in #2.