[vtkusers] vtk getting wrong OpenGL version number from mesa and macports

[Langer, Stephen A. (Fed)]

Hi Ben --

Setting MESA_GL_VERSION_OVERRIDE doesn't change anything.

However, the plot thickens.

From within vtkXOpenGLRenderWindow::WindowInitialize():

(1)  vtkXOpenGLRenderWindow::CreateAWindow(),  in the block under the comment "try for 32 context", is successfully creating an OpenGL 4.5 context (independent of the value of MESA_GL_VERSION_OVERRIDE).

(2) Then vtkOpenGLRenderWindow::OpenGLInitContext() calls glewInit() and finds that GLEW_VERSION_3_1 and GLEW_VERSION_3_2 aren't set, which they should be if the GL version is 4.5, right?   I don't really understand the difference between GL_VERSION and GLEW_VERSION_x_y.

Changing the setting of VTK_USE_SYSTEM_GLEW doesn't affect this behavior.  I made sure to uninstall macports' glew after turning off VTK_USE_SYSTEM_GLEW.

Sorry about forgetting to CC the list earlier!

 -- Steve

On 1/30/18, 9:33 AM, "Ben Boeckel" <ben.boeckel at kitware.com> wrote:

    [ Adding the list back to CC. Please keep the list in the loop. ]
    
    On Tue, Jan 30, 2018 at 03:17:25 +0000, Langer, Stephen A. (Fed) wrote:
    > I'm not explicitly requesting any profile -- I'm just trying to use
    > vtkXOpenGLRenderWindow, which is being created by
    > vtkRenderWindow::New().
    
    I asked since you said you were looking at the requests; I assume the
    profile is in there around the same area.
    
    > Is MESA_GL_OVERRIDE a run time variable, or do I set it when building
    > mesa or vtk?  Setting it at run time doesn't do anything, unless I'm
    > doing it wrong.. I tried
    
    Sorry, I have this one history item floating around that I really need
    to purge (done now). It's actually called `MESA_GL_VERSION_OVERRIDE`.
    
    >    % MESA_GL_OVERRIDE=3.2 [my program]
    > and it gave the same warnings as before.
    
    This is the right way of using it, just the wrong name :) .
    
    --Ben