Odd issue with using TV3d on a secondary form (VB6)

[fezman]

OK, so I have a project I'm using TV3d for (firearms training simulator) and the 3D rendering is only part of it, so I have the TV3D stuff in it's own seperate form, which I load and unload as necessary.

It was all working well this way, until I started using multiple atmospheres (rain, snow, day, night, etc). When it runs the first time everything works great, then when I'm dont I unload that form. When I go back to run another training session (the main form on this app stayed running) the rain or snow is screwed up, like it didn't unload properly. The rain / snow just sits in one spot (maybe at 0,0?) instead of moving with the camera.

And the worst part is that every now and then when this happens it will cause the computer to blue screen and reboot when the 3D app is starting up. I noticed it takes a few seconds after telling TV3D to quit before the memory usage drops to normal, but I don't think I'm trying to tell it to reload before that happens.

I think for the time being I can force the entire app to reload after finishing the 3D part without too much of an issue, but it seems very bad for this issue to cause blue screens on some computers (my dev system doesn't blue screen, but the systems in the simulator do). I don't currently have any debug logs from when the systems blue screen, but when the bug occurs the debug logs look normal.

Is this a bug, or possibly just something in my code?  :?

[fezman]

Here's a couple screenshots of the bug in action.

Rain Bug:


Snow Bug: (Notice the weird particle effects? I'm not using particles at all...)


Sorry for using Imageshack... just wanted to get some screenshots up in case that helps.

[fezman]

OK, I made a simple test project to make sure it wasn't my code that was screwing up somewhere, and try and isolate what is going on here. I took VB6 tutorial 7 (the landscape one) and added in another form, made that the startup form, added a button to spawn the 3d window (and some option boxes for fog/rain options), and a module to store the fog/rain option variables in.

I also moved the form_load events to a seperate sub that's called from a timer right after the form loads (otherwise the form_load never finishes, and causes an error from the calling form button press event), and added in the basic atmospheric options.

When I run it, the first time I spawn the 3d window it works perfect. Mouse look, fog, rain, keyboard movement all work. Then the second time I spawn the 3d window the fog still works but the rain never works right again, no matter how many times I close it and respawn it.

Another odd thing is that on the subsequent runs, sometimes mouse look or keyboard movement doesn't work, or sometimes both. It looks like this bug affects more than just the rain, but the input engine as well?

Here's a link to the test project:
http://thefezman.googlepages.com/home

[Icy_idee]

Same problem here. When I load my form with a TV3D on another form, my scene basically slants and I haven't figured out yet how to work this thing.