Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!ucsd!sdcc6!sdcc10!cs161agc
From: cs161agc@sdcc10.ucsd.EDU (John Schultz)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Simple sprite help please
Message-ID: <40@sdcc10.ucsd.EDU>
Date: 31 Dec 88 02:58:24 GMT
References: <160@csd4.milw.wisc.edu>
Reply-To: cs161agc@sdcc10.ucsd.edu.UUCP (John Schultz)
Distribution: na
Organization: University of California, San Diego
Lines: 38

In article <160@csd4.milw.wisc.edu> gregm@csd4.milw.wisc.edu (Gregory Jerome Mumm) writes:
[stuff deleted]
>my controlling it. In other words the 'missle' keeps going without
>me having to keep move it one pixel at a time. I envision a procedure
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  You're gonna have to move it yourself, as there is no "Magic" way
of doing it in parallel.  The code can look like this:

  INC(MissileX,deltaX);
  INC(MissileY,deltaY);
  MoveSprite(ViewPort,MissileSprite,MissileX,MissileY);

  You'll need to do bounds/collision checking too.
  Just place in your main animation loop.   

>Last but not least I need to know when a missle hits one of the space ships.

  If you are only using 2 opposing spaceships, each with independent
missiles, then you can check the Sprite Hardware Collision Register
(Explained in the back of the Hardware manual) for collisions.  Only certain
pairs register collisions, so choose carefully.
  For more complex animation, use a "Proximity" equation like:

  PROCEDURE proximity(x,y,enemyx,enemyy, 
                      width,height      : INTEGER): BOOLEAN;
  BEGIN
    RETURN (ABS(x-enemyx) < width) AND (ABS(y-enemyy) < height);
  END proximity;

  This function will return TRUE when the "rectangles" defining your
shapes overlap.

>Csnet:	  gregm%uwmcsd4@uwm	             Greg Mumm 

  Hope this helps.

  
  John Schultz