[vtk-developers] [VTK 0012703]: vtkOpenGLGPUVolumeRayCastMapper: Exception in LoadExtensions causes InRender flag to stay set and never render again

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://vtk.org/Bug/view.php?id=12703 
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Reported By:                CJ Bourn
Assigned To:                
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Project:                    VTK
Issue ID:                   12703
Category:                   (No Category)
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     backlog
Project:                    TBD 
Type:                       crash 
Resolution:                 open
Fixed in Version:           
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Date Submitted:             2011-11-03 10:26 EDT
Last Modified:              2011-11-03 10:26 EDT
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Summary:                    vtkOpenGLGPUVolumeRayCastMapper: Exception in
LoadExtensions causes InRender flag to stay set and never render again
Description: 
In vtkOpenGLGPUVolumeRayCastMapper, if the GL context could not actually be set
up, then all the calls to glGetString() will return NULL. These results are then
blindly passed to strstr() which results in an exception. This method gets
called during Render() which causes the InRender flag of vtkRenderWindow to
never be cleared and thus rendering will never occur again. The fix is simple,
eg Line 2160:

  const char *gl_version=reinterpret_cast<const char
*>(glGetString(GL_VERSION));
  if(gl_version != 0 && strstr(gl_version,"Mesa")!=0)
     ^^^^^^^^^^^^^^^^^^ 
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Issue History 
Date Modified    Username       Field                    Change               
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2011-11-03 10:26 CJ Bourn       New Issue                                    
2011-11-03 10:26 CJ Bourn       File Added: vtkOpenGLGPUVolumeRayCastMapper.cxx 
                  
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