On Wed, 1 Nov 1995, Rob Hagopian wrote:

> >Well, just so you know that LC's have some problems when trying to be
> >compatible with other Macs' Color Quickdraw.  You have to call an extra
> >function everytime you setup a color grafport.  It took me a whole year
> 
> What call? That would be good to know! Thx!
>                         -Rob H.

Sorry it took so long to reply.  I had to search through piles of source 
code to find it.  I found this extra line of code somewhere when spending 
a year trying to get a simple offscreen pixmap call to work.  When I 
found it, I was thoroughly disgusted.  It wasn't in any of my references, 
and I have lots of them.

Basically when you create an offscreen pixmap (probably onscreen, too) 
you create a new pixmap and open a new color port and set the port's 
portPixMap to that new pixmap, then:

Rect anotherRect; /* rectangle depicting size of port (0,0)-(ht,wd) */
CGrafPtr anotherPort;  /* I'm assuming this is already setup */
...
(**anotherPort->visRgn).rgnBBox = anotherRect;
...

I don't know why the LC's require setting up the visible region, but I 
tried a program both with and without this code on my LCIII and it only 
worked with the code.  I don't even know why/if it doesn't work on 
non-LC's but I'm assuming that the code can't hurt.

If somebody can explain this, go right ahead.  I've spent two years 
trying to do animation and other "game" graphics on my LC3 and so far, 
nothing works!

BTW:  GIve me one more week, and I'll have BSD on my mac... just about 
the time I'm considering buying a workstation!  I'll never win.  :(

--Rick C. Petty,  aka Snoopy
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