HACD : Hierarchical Approximate Convex Decomposition by Khaled Mamou Sample Application

I have just created and made available a test application for people to use/experiment with Khaled Mamou's excellent HACD system.

TestHACD on Google Code

Due to requirements that I have at my job, I had to refactor the code so that it did not use any of the standard template library (STL) and 100% of all memory allocations had to be trapped by a user provided allocator. (i.e. no global new/delete, malloc, free).

One of the more challenging things to factor out regarding the STL was the use of the STL set and map containers.  To accomplish this what I did was refactor a copy of the EASTL (written by Paul Pedriana).  Even though Paul's EASTL is a dramatically smaller code base than the full STL implementation, I went a step further and refactored his code so that I extracted *only* the STL map/set containers and nothing else.  I then put this refactored code into just three small source files where all memory allocations and data types could be trapped and revectored.

There is a single header file in the provided project 'PxSimpleTypes.h'.  You can modify the data types and memory allocation macros in this one header file to make the source conform to the coding standard of your own game engine, or at least it provides a single easy location to do some global find/replace on the source to make it conform to your internal standards.

Khaled's algorithm produces absolutely amazing results much better than my version ever did.  However, one thing I have yet to be able to get his to do is produce just one our two hulls.

With the provided sample mesh no matter what I set the concavity threshold to, no matter how high, I still get 14 convex hulls.  I don't know if this is a limitation of his algorithm or I am not exposing all of the correct parameters at this time.

If you wish to make improvements to this code, please let me know and I will add you to the Google Code project so you can make changes.  Also, sometime in the next week, I am going to revise the code to auto-generate a skeletal deformed mesh from the HACD output.  I will add this to the TestHACD open source project.

Be aware that Khaled's algorithm can be extremely CPU intensive.  With triangle meshes with very large vertex counts; it could possibly take an extremely lengthy period of time.