# CombineImages - lots of OpenGL rendering messages.

**URL:** https://discourse.vtk.org/t/combineimages-lots-of-opengl-rendering-messages/4385
**Category:** Development
**Created:** [October 8, 2020, 9:35pm UTC](https://discourse.vtk.org/t/combineimages-lots-of-opengl-rendering-messages/4385 "2020-10-08T21:35:51Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![amaclean](https://discourse.vtk.org/user_avatar/discourse.vtk.org/amaclean/32/224_2.png) [@amaclean](https://discourse.vtk.org/u/amaclean)
#### Post date: [October 8, 2020, 9:35pm UTC](https://discourse.vtk.org/t/combineimages-lots-of-opengl-rendering-messages/4385/1 "2020-10-08T21:35:51Z")

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@ken-martin, You may have some ideas here.

I have been updating the VTK Examples and this example produces a huge number of OpenGL generic warnings and errors: [CombineImages](https://ajpmaclean.github.io/web-test/site/Cxx/Images/CombineImages/). An image is finally produced.

The test data is found in: `vtk-examples\src\Testing\Data`, namely `Ox.jpg` and `Gourds2.jpg`.

Thanks  
Andrew

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### Author: ![amaclean](https://discourse.vtk.org/user_avatar/discourse.vtk.org/amaclean/32/224_2.png) [@amaclean](https://discourse.vtk.org/u/amaclean)
#### Post date: [October 10, 2020, 9:55pm UTC](https://discourse.vtk.org/t/combineimages-lots-of-opengl-rendering-messages/4385/2 "2020-10-10T21:55:28Z")

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See: [https://gitlab.kitware.com/vtk/vtk/-/issues/18025](https://gitlab.kitware.com/vtk/vtk/-/issues/18025)