Re: [stella] New game: Ace 2600

Subject: Re: [stella] New game: Ace 2600
From: KirkIsrael@xxxxxxxxxxxxx
Date: 27 Oct 2003 12:41:59 -0000
> Kirk Israel wrote:
> >Well, the thing I'm wondering about is how any of the 4 missiles
> >has to be able to detect hits on any of the 4 players.  Wouldn't 
> >you tend to miss certain events if the flickering was off?  
> That depends on the size and speed of the objects. The smaller and 
> faster the objects are, the more problems you will have with 
> hardware collision detection.

You might also have to come up with an intelligent flicker
routine...for instance, if you always displayed 
player and bullets 1 + 2 on one frame then 3+4 on the alternate,
1's bullets could never hit 3 I think, and vice versa.
> > Or would you suggest using bounding rectangles and exact 
> > positioning or something?

> A perfect detection would require to calculate and check *all* 
> intermediate points for both objects between two frames. But 
> that's usually not necessary. As long as the player doesn't notice 
> wrong or missed collisions everything is just fine. know, if you were using exact horizontal positioning 
for everything...if the missile a square, once you've figured out 
they're in the same bounding rectangle, you could probably just 
do some ANDing against the player graphic for that row, and the 
binary digit 1 or 11 leftshifted.  Might be a bit fiddley, but 
actually easier to do than on some systems where you're not working
at such a low graphical level.

"Evaporation is God's paper towel" --Dylan Murray

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