🚀 go-pugleaf

   From article <1992Jul26.181425.207@micor.ocunix.on.ca>, by goss@micor.ocunix.on.ca (Timothy D. Goss):
   > How about this?  Create a grid which represents the graphics screen but one
   > which does not represent every pixel.  Group pixels into 2x2, 4x4 etc groups.
   > This grid can be used to represent the approximate location of each sprite or
   > background image.  To check if a sprite has collided with something simply
   > check its destination position in the grid to see if any deadly objects are
   > there.  The contents of the grid could be id bytes or something.  Each time
   > a sprite is moved, its position in the grid is also updated.

       Here's where some data structures could come in. Its most probable that 
   the actual array will be mostly empty. So I advise you to use a sparse array
   instead. This will reduce the amount of memory consumed.

 Well that saves memory but it's a SLOW data structure.\
 What he needs is a quad tree wich is fast and eats up very few mem
 AND it doesn't force the grid to a fixed dimension and allows
 several objects with the form you like even disconnected.

 For more info see some books on spatial data structures and use
 the quad-tree variant most suited for your app.

	Hope this helps,
			Acacio Cruz
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Acacio Justino Calcada da Cruz| BITNET/Internet: axc@fct.unl.pt
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