Message-Id: <199609150201.VAA17517@ghgcorp.ghgcorp.com>
Comments: Authenticated sender is <rbachtel AT mailman DOT ghgcorp DOT com>
From: "Bachtel" <rbachtel AT ghgcorp DOT com>
To: djgpp AT delorie DOT com
Date: Sat, 14 Sep 1996 20:51:56 +0000
MIME-Version: 1.0
Content-type: text/plain; charset=US-ASCII
Content-transfer-encoding: 7BIT
Subject: GrBitBlt - quest(ions)

I was wondering if someone could give me a concise snippet of code, 
using GrBitBlt as a sprite function (_if_ this is possible). (Grx2, 
btw). I've looked at BitBltTst.c, and as far as I can see, it doesn't 
do what I need, which is namely a simple sprite put. When I do:
GrContext sprite=GrCreateContext(40,40,NULL,NULL);
GrBitBlt(sprite,0,0,NULL,0,0,39,39,GrWRITE);

then

while (!kbhit())
{
GrBitBlt(NULL,random(600),random(600),sprite,0,0,39,39,GrWRITE);
}

BitBlt gets the data area okay, but if it happens to write over part 
of the screen where it originally got the sprite, it incorporates the 
new image into the sprite data. While it is cool looking, can 
somebody tell me a way to avoid it? The GRX2 manual didn't say, and 
I'm saving D/l Grx1 as a last resort, if possible.

Thanks for _any_ and _all_ help,
Jeff

(*PS: No, this wasn't in manual :)