Rendering improvements

[nevenjohnson]

Summary

What features did you add, bugs did you fix, etc?

Add support for normal mapping in the sim. This improves visual fidelity and can be used to make simulated pointcloud data more detailed. Normal mapping is toggleable in case it produces undesired results for a particular use case.

Also updated shaders to optionally use true PBR (incorporates metallic and roughness values per mesh). This is toggleable through checkbox in the sim GUI.

Did you add documentation to the wiki?

No

How was this code tested?

Tested this code in the sim by toggling normal mapping on and off and by toggling PBR on and off. Performance impact (on my machine) seems negligible.

Did you test this in sim?

Yes

Did you test this on the rover?

No

Did you add unit tests?

No

[ejhon1116]

@nevenjohnson is this real chat or can i close

[nevenjohnson]

Yeah ts is real I just ran into some issues when John finally got around to considering it and I didn't fix in time. Would be fire to get this in soon tho

[qhdwight]

"Rendering improvements" and no screenshots

[nevenjohnson]

This PR adds 2 main improvements: physically based rendering (PBR) and normal mapping. Physically based rendering uses more realistic shading of models that is grounded in physics. As compared to the existing rendering, this should improve the appearance of models, especially with respect to material properties like roughness and metallic character. This PR also updates the existing basic shaders to fix some bugs. Normal mapping adds much more visual detail to models without increasing the complexity of their geometry. Screenshots below.

main:
new default:
pbr:
normals:
pbr+normals: