Path: chuka.playstation.co.uk!news
From: "Andrew Partington" <a.partington@yaroze41.freeserve.co.uk>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: offscreen sprite/line/etc drawing - how?
Date: Thu, 9 Sep 1999 16:59:44 +0100
Organization: PlayStation Net Yaroze (SCEE)
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Hi everyone

I am trying to do a pixel-perfect collision routine that will support
scaled/rotated sprites.  I have the collision detection part working
perfectly, but as things stand it won't support scaled/rotated sprites.
Basically I have a 64*64 pixel area in VRAM which I copy the collidable
sprites to (from another area in VRAM using the MoveImage() function),
before copying the area to main RAM for pixel-by-pixel collision testing.
Obviously, this will not handle when the sprite is scaled or rotated.

What I need to know is:  is there any way of using GsSortSprite() etc to
draw to my offscreen area in VRAM?  And how would I go about doing this?  I
really need to be able to draw scaled/rotated sprites to my offscreen VRAM
area (at 320,447 BTW), or else my collision routine is not that much use to
me!

I've only been seriously using my Yaroze since I graduated from uni, so I
don't know too much about ordering tables or all the rest of it.  I don't
want to use MoveImage()  etc to take a copy of the sprite from the display
area, since I would be copying all the other garbage surrounding the sprite
as well, and I don't want that.


Cheers


Andy