Unreal does not provide an opengl context for third party libraries?

Development Rendering
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1

The error I get, “No override found”, means that VTK’s object factory mechanism could not instantiate the right OpenGL class (vtkOpenGLRayCastImageDisplayHelper, in this case) for the super class used (vtkRayCastImageDisplayHelper, in this case).

This happens if I do not create the right OpenGL context or if there are any GLEW errors when instantiating the render window. First off, my computer has the latest OpenGL and a card that launched 2 months ago so OpenGL not being available should not be a problem. I have no idea how UE4 chooses between OpenGL and DirectX or if we can change that.

What I am trying to do is to add volumetric rendering to UE4. I am trying to use VTK to do the rendering and then simply display that in UE4 instead of writing everything myself. From what I have read I should start by looking at the RHI module, but before I think about incorporating it into the renderer I wanted to render it by itself and then simply importing the rendered framedata into UE4 as a texture always turned towards the user.

The reason for why I trying to do this is because I want to try to mix scientific visualization and game mechanics in VR to offer an improved experience for scientists and at the same time make science more approachable and interesting for younger ones.

I am not looking for an answer, as I think this should be more work than a simple text answer here can cover, but I would appreciate someone with experience with the UE4 environment helping me by pointing out possibilities and giving advice. That would save me a lot of time and work.

(If I am lucky my god and savior Rama will bless me with his guidance. :P)

2

I tried launching the editor using -opengl3 or -opengl4 aftern enabling these in the project settings, but nothing helps. I still cant make UE4 provide the OpenGL context the thirdparty library needs.

3

After many attempts I have to conclude that you cant get the context or create one. I made my own thread and I called a single function that should ask the driver to give me a function pointer that I can use. However, nothing worked out and I crashed every time I called that function. As such I am left with no choice but to use inter-process communication to get the result I needed.

4

Are you sure about it?You run on Windows or Linux?If the engine runs on OpenGL (Linux is the case),then you should have the context available just out of the box.

5

At least I was unable to do it. I am on a windows PC and I started anew thread and tried getting the context. It did not work. I tried a lot of things. Nothing worked. If you rae able to do it, please tell me.