LDraw snapshots coming up empty

[Ber]

I suspect that Roland was right and this is a driver problem. Bear in mind that while both LDView and LDCad use OpenGL, they do so in very different ways.

The first thing to try is to disable LDView's use of all OpenGL extensions. If this fixes the problem, you can then try to narrow down which specific extension(s) is/are causing the problem. (You definitely want LDView to be able to use as many extensions as possible.)

To disable LDView's use of OpenGL extensions, do the following:

• Run regedit
  
• Browse to HKEY_CURRENT_USER\Software\Travis Cobbs\LDView
  
• Right click on the LDView key in the tree and select New->DWORD (32-bit) Value
  
• Rename the new value to IgnoreAllOGLExtensions
  
• Edit the value and set it to 1
  

Exit LDView if it is running and run it again. Then open your model and save the snapshot. If this doesn't fix the problem, then I honestly have no idea what is going on. If it does fix the problem, the next step is to try to figure out which OpenGL extension is causing the problem.

To do this, edit the IgnoreAllOGLExtensions value and set it to 0. The most likely other problem extensions are FBO, PBuffer, and PixelFormat. So try creating one or more of the following DWORD registry values (in the same LDView registry key) with values of 1:

• IgnoreFramebufferObject
  
• IgnorePBuffer
  
• IgnorePixelFormat
  

To be honest, if "IgnoreAll" works, and none of the above works (even all three), then I'll be very surprised. But these are the other keys that can be set to ignore other extensions:

• IgnoreAniso
  
• IgnoreMultiDrawArrays
  
• IgnoreMultisample
  
• IgnoreMultisampleFilterHint
  
• IgnoreVAR
  
• IgnoreVBO
  

Hi again

Thanks for giving me these steps to try!

So, my starting point for testing the registry settings was using the latest 64-bit you recommended I download. Since my last post, I have also tried installing the whole LDraw package on a second computer, a desktop gaming computer. All this talk about OpenGL, I figured a better video card than on my basic laptop might make a difference. What I found on the desktop was, same problem! black output files.

However, when I tried the registry fixes, they worked on both the laptop and desktop, but each needed a different 'Ignore' setting!

Desktop:
IgnoreAllOGLExtensions = 1
Result: good png

IgnoreAllOGLExtensions = 0
IgnoreFramebufferObject = 1
Result: black png

IgnoreAllOGLExtensions = 0
IgnorePBuffer = 1
Result: black png

IgnoreAllOGLExtensions = 0
IgnorePixelFormat = 1
Result: good png

laptop:
IgnoreAllOGLExtensions = 1
Result: good png

IgnoreAllOGLExtensions = 0
IgnoreFramebufferObject = 1
Result: black png

IgnoreAllOGLExtensions = 0
IgnorePBuffer = 1
Result: good png

IgnoreAllOGLExtensions = 0
IgnorePixelFormat = 1
Result: black png


So, OpenGL really not behaving for LDView! But I have a working solution for LDView on both computers now, thank you.

I hope my results are helpful for you. If you would like any other info or testing from me to help you make use of my test results, let me know and I'll be happy to help.