Increasing MAX_WIDTH/MAX_HEIGHT in Mesa does have it's problems if
you go too far though.

Here's a little more detail from Brian Paul.

Alan.

----- Forwarded message from Brian Paul <[EMAIL PROTECTED]> -----

Unfortunately, it's not that simple.  Increasing MAX_WIDTH has a few
implications:

1. A number of temporary scan-line buffers are dimensioned to MAX_WIDTH.
   On Macs there's a 32KB stack frame limitation.  We're using some
   macros (DEFMARRAY, etc) to allocate these temporaries in a number of
   places.  It works, but if we crank up MAX_WIDTH to 8K or 16K there'll
   probably be some breakage.  There's also evidence that large stack
   frame allocations on Win32 cause slow-downs.  That's not a real big
   deal though...

2. The real issue may be with line/triangle rasterization.  I'm using
   fixed point math quite heavily in the triangle code.  I'm afraid
   that large values for MAX_WIDTH will cause overflow problems, causing
   triangle drawing to blow up.

I can't increase the default MAX_WIDTH too much (maybe 3K) until I've
done some testing to see what happens.

Feel free to forward this info to the xpert list if you want.

-Brian
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