Blender Git Loki

* Tablet support fixup

This commit should hopefully fix some of the problems some people were
having with tablet support in sculpt mode, and also the problems I made
visible with my previous commit related to number field dragging.

Now, all the ghost related stuff is tucked away in ghostwinlay.c and a
simple Blender API, similar to the existing get_mbut() for example, is
provided to access the tablet data. As with the other mouse related data in
Blender, the tablet data is cached upon each mouse move or click, in the
Window struct.

You can now just use:

float get_pressure(void);
void get_tilt(float *xtilt, float *ytilt);
short get_activedevice(void);

to get such data from the tablet. Documentation on the returned data
is in ghostwinlay.c in the _Window struct definition.


Brecht and Nicholas, I've updated the painting and sculpt code and it works
just fine here, you may want to give it a check though to make sure I
haven't done anything silly.