🚀 go-pugleaf

In article <1992Aug20.132131.9585@uoft02.utoledo.edu> evaleros@jupiter.cse.utoledo.edu (Elsa S. Valeroso) writes:

>	I have just compiled PEXtk Version 1.0 based on DEC Contrib PEXlib 5.0
>	on one of our Sun SPARC station IPCs. I ftp'd the source code and the 
>	library from export.lcs. 

>	My question is: "When I execute any of the test programs, shouldn't the
>	workstation be clear of any previous images drawn by a previous test 
>	program? 
>	[...]
>	current one. It seems that the problem lies in the double-buffering. 
>	Test programs which do not use double buffering seem to be working 
>	fine.

Depends on the PEX server you are using. I believe that SunPHIGS2.0
only supports double buffering on graphics accelerators that have it
in hardware. ie, not IPCs, you need a SPARC2 with GS or GT
accelerator.

The SunPEX server extension is based on the PEX SI although with
optimisations for their various accelerators. I guess (we have yet to
get our hands on the Sun PEX server) that they will use the same logic
as with Sun PHIGS - support double buffering only on their better
graphics accelerators.

If you are using the PEX consortium SI, well that does not support
double buffering or HLHSR *at all*. It is a code sample; designed to
be read as much as run.

So your diagnosis seems completely correct - programs that use double
buffering will fail. You have not done anything wrong, this is the
expected behaviour.

--
Chris Lilley
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