ELCO SISTEMAS, S.A. (elco++at++ran.es)
Thu, 1 Aug 1996 09:16:30 +0100
Sorry, for I have been sending this e-mail previously attached as a
microsoft word
document, instead of plain text. Hope this time it is Ok:
I am asking for help about how to use the stencil buffer with Performer 2.0.
I am quite sure that somebody must have dealt with this problem before.
I am using Performer 2.0 with an Indigo2 High IMPACT with 4 TRAM. This
machine has Open/GL native graphics hardware.
I need to create a sort of binocular with a graduated grid, to look trough
and see
the database terrain augmented. I have already solved putting the grid, using
the (unexisting in OpenGL) overlay plane , in a similar way as Performer does
with the stats channel. But I am still having series problems with the use
of the
STENCIL buffer, so as to draw the shape o a black binocular.
I am using a Post-Draw Callback function, within the framework of PERFLY, and
I have achieved some results, but I am having a problem with the shape of the
binocular flickering between the desired black and an strange sort of
clearScreen
apparently every frame. This problem misteriosly dissapear if I do a window
resize, or I do iconize the window and restore it the maximum size. But as soon
as I switch the binocular off, and on again, the problem of the flickering
appears
again as well.
I would hugely appreciate if somebody could tell me where to find any source of
information about the use of the stencil buffer with Performer 2.0, or any
fragment
of source C code making use of it.
Thanks in advance.
--------------
Rafael Garcia
ELCO Sistemas
Simulation Division
Madrid - Spain
--------------
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