Path: chuka.playstation.co.uk!scea!peter_alau@playstation.sony.com
From: "Antony Arciuolo" <antony.arciuolo@mail.trincoll.edu>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Sprite Rotation questions.
Date: Sat, 22 Aug 1998 15:38:32 -0400
Organization: SCEA News Server
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I have a 2d scrolling world with 20 32x32 sprites that are all the same.

Sprite[0] is controlled by pad1 and works. When you press left/right, a
function called RotateCW(Object *obj, short degrees) or RotateCCW(Object
*obj, short degrees) is invoked. These functions either add or decrement
obj->spr.rotate by (degrees * ONE), and then make an adjustment if the
rotation is out of the 0-360 range. Here are the functions.

void RotateCCW(WOBJECT *obj, short degrees)
{
 obj->spr.rotate -= (MAKEFIXED(degrees));
 if (obj->spr.rotate < 0) obj->spr.rotate += (MAKEFIXED(360));
}

void RotateCW(WOBJECT *obj, short degrees)
{
 obj->spr.rotate += (MAKEFIXED(degrees));
 if (obj->spr.rotate >= MAKEFIXED(360)) obj->spr.rotate -= MAKEFIXED(360);
}

Now I want Sprite[1] to "look at" Sprite[0] when I press a button on pad1.

After doing all the complex stuff to get this to work, and receiving the
problem I will describe shortly, I simplified the situation to having
Sprite[1] rotate in a circle.

So:

void main(void)
{
    ...

    handlePad1();

    ...

    RotateCW(&Sprite[1], 5);

    ...

}

This runs fine as long as Sprite(0) is not moving, but when there is a
non-zero value for the pad1 buffer, the program freezes and  I get this
message:

GPU
timeout:que=1,stat=5602220f,chcr-01000401,madr=0000000d,func=(80029e50)(801e
052c, 00000000)

What could cause a GPU timeout like this? If I comment out the RotateCW
line, everything works normally.

- Tony