[stella] Angular movement

[Glenn Saunders <mos6507@xxxxxxxxxxx>]

At 10:30 AM 1/13/2004, you wrote:
> The easy way:
> First you decide how many angles you want and what should be the ball
> speed.
>
> For each angle you need two values, one for the x- and one for the
> y-speed. Each values consists out of two bytes to store fractional speeds.
>
> E.g. the ball speed should be 3 pixel/frame, for an angle of 30° you
> get a speed of 1.5/2.6 (x/y) pixels/frame. Converted into fractional
> values you get 1/128 and 2/153.


This is what you mean by a sine wave?  I already have these two tables but 
while I can get an accurate angle of movement, the speed is not consistent 
from angle to angle.

Is there a mathematical formula I can use to precisely calculate the 
numbers because something as simple as "45' angle up means .5/.5" isn't 
working.  I could manually tweak the numbers and eyeball it but I'm sure 
there has to be a formula.

Is this in any way related to the polar coordinate thread from way back?

----------------------------------------------------------------------------------------------
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/