Hi List,

Line 593 of pdp_imageproc_portable.c:

    /* affine x, y mappings in screen coordinates */

    double mapx(double _x, double _y){return cx + izx * ( c * (_x-cx) + s * (_y-cy));}

    double mapy(double _x, double _y){return cy + izy * (-s * (_x-cx) + c * (_y-cy));}

These lines are found _inside_ a function called pdp_imageproc_resample_affinemap_process.

It's fun to focus on the substring "portable.c", and just read these lines a few times. :)

-Jonathan