I don’t have a more elegant way of expressing the problem, so I took some screenshots. I’m working on a hat (hence the sphere) and as soon as I start manipulating the mesh, it collapses.

1-2: New scene, create a sphere mesh.
3: Using edge select mode, and delete everything in the lower half of the sphere.
4: Manually select the edge loop around the equator (edge loop selection and range selection are not working, but that’s another problem.)
5: Scale the selected edge loop. As soon as I do this, the wireframe “disappears.” The selection I’m working with remains, but the transform controls are
6-7: By changing the view mode to Shaded, I can see that the polys are still there, but they’ve been mangled.

Also, if I change the view mode to “shaded” in the “camera” viewport (anyone know why they changed this from the “user” default?) my wireframes disappear in ALL the viewports and I can’t get them back.

Has anyone else experienced this? I’m running this on 32-bit windows XP if that makes any difference.

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I thought Camera was always the default.

What video card and driver are you using?

Version 6.5 defaulted to “User” in top left, but it’s not really a big deal.

System specs… right. The video card is a Sapphire Radeon 9600XT (256 MB) and the driver is 8.593.100.0 If it matters, the system is an Athlon XP 3200+ and 1.5 GB memory. I know I need to upgrade, but it’s not really an option at this moment.

Thanks for your help!

Check the antialiasing setting of your graphic card: set it to Application-controlled.

http://usa.autodesk.com/getdoc/id=TS13522800

Okay, I checked that and there was no option for AA. I downloaded the latest Catalyst driver (per suggested at the Softimage help link you posted) and made sure that all the settings that could be application-controlled were.

I still have the problem. Also, and this was present before as well, if I change the view mode to Shaded from Wireframe, all the geometry simply disappears and this cannot be undone.

Thanks for the ideas, anyway. Any other suggestions?

Try setting the XSI_EMULATE_OPENGL environment variable to 1.4. Add this line to your setenv.bat:

set XSI_EMULATE_OPENGL=1.4

This will prevent Softimage from using newer OpenGL features, which can sometimes cause strange problems with certain cards.

Okay, that did not immediately fix the problem.

However, I just realized that toggling “hide” (H key) refreshes the display. The geometry is still there… but it toggles off even when the geometry is not hidden. By toggling hide, the mesh ‘reappears’. Basically, the geometry doesn’t seem to be destroyed, just invisible. Selection makes the selected edges visible but only while selected.

I suspect my video card may be to blame. I turned hardware acceleration to “None” in the display properties panel. Guess what? The mesh displays normally. I can scale it, I can turn on shading, nothing warps, disappears, anything.

Any fixes for this? Barring a solution, is there a way to set hardware acceleration per-application?

Thanks to both of you for the advice so far.