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Forum Topic - devg-extreme2 is omitting points when glDrawArrays() is executing.: (3 Items)
   
devg-extreme2 is omitting points when glDrawArrays() is executing.  
Kevin Raymond reports the same problem with devg-gma9xx driver here:
http://community.qnx.com/sf/discussion/do/listPosts/projects.bsp/discussion.bsp.topc6952

I'm able to reproduce this problem on devg-extreme2, but test application will be in binary form, since it using a lot 
of dependencies to software which is under development.

The same binaries work fine using software GLES implementation. Under devg-extreme2:

sphere - uses QNX's native egl interface. All points on sphere are drawed correctly.
sdl_sphere - uses SDL which initializes all GLES stuff, like it done in "sphere" test, applications are very similar to 
each other, even the same. But the sphere located in the middle-bottom has been drawn incorrectly, when sdl_sphere 
renders sphere of points.

Take a look into it.
Attachment: Text pointstest.tar.gz 740.52 KB
Re: devg-extreme2 is omitting points when glDrawArrays() is executing.  
Additional information. Problem with points disappearing using devg-extreme2 graphics driver could be reproduced if 
current display color depth is 15 bpp (1555) or 16 bpp (565). But while using 32 bpp depth (8888 format) all works fine.

Re: devg-extreme2 is omitting points when glDrawArrays() is executing.  
Hi I work with Kevin Raymond and I came across the problem of invisible points in i830 in QNX 6.4 with a core duo 
machine while writing a program that uses OpenGL to draw a simple set of points in 2D.  I modified the photon GL gears 
app to showcase this problem, if you run it with gma9xx you can see one of the gears, in i830 you see nothing.  I will 
attach the program and quote the included README:
---------------------------------------------------------------------
This code demonstrates the issue with the i830 driver in QNX.  Tested in i830 display on a Core Duo with intel 945 
integrated graphics.
When run in i830 with 16M color (we have found this configuration the most stable) you will see a black screen.
When run with gma9xx with 32K color (16M crashes QNX sometimes..) you do see the green gear in the bottom right part of 
the screen drawn as faint points.

The problem at hand seems to be that in the i830 driver QNX will not render GL_POINTS on plane z=0.  This is incorrect 
behaviour as all other OpenGL implementations render GL_POINTS at z=0.  Doing a glTranslatef(0.0, 0.0, -1.0) will allow 
the points to show up but in some cases it is important to render with 0 depth.




--- Card from pci -v -------
Class          = Display (VGA)
Vendor ID      = 8086h, Intel Corporation
Device ID      = 2772h,  82945G/GZ Integrated Graphics Controller
PCI index      = 0h
PCI Mem Address = ffa80000h enabled
PCI IO Address  = ec00h enabled
PCI Mem Address = e0000000h enabled
PCI Mem Address = ffa40000h enabled
PCI Int Pin    = INT A
Interrupt line = 5
CPU Interrupt  = 5h
Attachment: Text GLES_i830_QNX64_bug_sample_app.tgz 23.98 KB