[AD] rotate direction

["Trent Gamblin" <trent@xxxxxxxxxx>]

Writing some code for my game I came to realize that the C trig
function sin behaves differently than the al_draw_rotated_*
functions. "sin" starts at 0 (3 o'clock) and moves clockwise so that
pi/2 is at 6 o'clock. The allegro functions however go counter
clockwise, starting at the same 0 with pi/2 at 12 o'clock.

Now we have the option to change or keep this behavior.

First there is the argument that everything should work the same so
we follow the C conventions.

On the other hand, OpenGL by default works like Allegro does at
present. Also, at least in Canada, in school we're taught with
angles that follow the same behavior.

So do we want to harmonize with C or stick with the more "standard"
(IMO) convention (no change to current code)?


Trent :{)>