Re: [Burrtools-discussion] burrtools lib

[Andreas <ro...@us...>]

Hello,

Please don't use HTML for emails. I tend to immediately remove them due to 
spam.

> I'd like to use the burrtools library to analyze some problems. I have some 
> questions:

> - What ist the difference between the classes voxel_0_c, voxel_1_c,
>   voxel_2_c and voxel_3_c? Why is it necessary to derive
>   four different classes from voxel_c? 

The inherited classes are for the special space grids while the base class 
contains common functionality. The special code is mainly about 
transformation (rotation) of the voxel space and also about finding neighbor 
voxels. The numbers are as follows 0 for brick, 1 for triangular, 2 for 
spheres, 3 for rhombic, 4 for tetrahedral octahedral grid.

Normally you are not supposed to use the constructors directly. If you want a 
voxel space that fits into a certain puzzle p use

p->getGridType()->getVoxel(.....) 

functions. They will always return the proper derived class. Also you nearly 
nowhere need to construct the classes directly. Most of the time (well in 
cases with derived classes) you will use the gridType factory. It contains 
factory functions for all those hierarchies.

> - The piecegenerator that comes with burrtools 0.4.2 is not working for me. 
>   Is somebody working on a piecegenerator which is able to  
>   - calculate pieces by varying the voxels VX_VARIABLE  
>   - build Pentominos, Hexominos, ...   ? 

Sorry, but the release version of 0.4.2 doesn't contain a valid piece 
generator. In the development version that file is removed. I never got that 
finished. The development version does contain something that is suitable for 
constructing some pieces but it works differently.

Best would be to download the current development version (using darcs) and 
look there. There are many (really many) changes in there. The new piece 
generation functions are documented in the manual, so you can look there, or 
ask here once you get the development version running.

It is certainly possible to generate pentominos and hexominos with it.

Andreas