I have not tested this patch.
Icons are stored in textures/misc/mpi000
, a square texture that is used as follows:
- The first 0.390625% from the top and left are ignored.
For the original size 256 this amounts to exactly one pixel. - There is a twelve by twelve grid using 8.204125% per tile.
For ths original size 256 this amounts to exactly 21 pixels. - The last original tile 143 is reserved for the selection rectangle
To extend this, the easiest way would be to increase the texture size to 512x512.