OpenVR

[Robadob]

This branch is work adding VR support.

At current it's able to render to a VR headset. override BB.

• ~Need to add controller input~
  • ~SceneVR extends public Scene to provide access to VR specific features (aka tracked devices).~
  • Need to stop tracked devices sharing scene graph
  • ~Need to extend Renderable to act as scene graph. (so models can be attached to controllers)~
• Override tracked device models
• Allow user to move the vr origin around
  • This is now possible via HMDCamera::setWorldMat(), would be nice to add proper locomotion however. Attempted grip skiing, similar to sports bar vr, however it was very unstable and I don't think I got the maths quite correct.
• ~Need to add backbuffer override method~ (untested)
  • ~Need to make backbuffer auto grab dimensions etc. (flawed if it doesn't tbh)~
    • ~Make whole class static, add dimension/clear colour privates same as visualisation uses to~
• ~Need to update Overlay/Sprite2D to support flipping texture hoz/vertical (via tex coords?)~
• ~Need to fix rendering of tracked devices~
• ~Need to fix companion window~
• ~Two pass scene tries to resize backbuffer? why?~

Misc:

• Primitive PolyLine

• VAO class for holding vertex attribs, potentially reorganise shaders/entities to work inverted.

• VR portal

Changelog:

• Improved BackBuffer so that it's dimensions are managed by Visualisation, making it more portable.
  • BackBuffer::useStatic() can now be called to enable the backbuffer without holding an instance.
• Extended Renderable to support scene graph behaviours.
  • Extended Shaders to allow overriding model matrix at render. (taken from Assimp branch implementation)
• Added Entity2 and related classes from material_light_uniforms branch, this is unfinished but capable of rendering models with basic materials at current.
• Added VisualisationVR, SceneVR and several other VR related classes for drop-in VR support.
• Added flipVertical() and flipHorizontal() methods to Overlay
• Added drawing primitives Points, Lines, 'PolyLinefor providingglVertex` replacement.

[Robadob]

http://on-demand.gputechconf.com/siggraph/2016/presentation/sig1648-mark-kilgard-virtual-reality-rendering-features-nvidia-gpu.pdf NV_stereo_view_rendering (single pass stereo render) EXT_window_rectangles (saves rendering 17% of unused frags to each eye, does this also do LensMatchedShading?).

Slide 105 onwards: http://on-demand.gputechconf.com/siggraph/2016/presentation/sig1609-kilgard-jeffrey-keil-nvidia-opengl-in-2016.pdf

[Robadob]

OpenVR_2019 branch now contains maual merge of old OpenVR code into master/SceneGraph2.

Next step seems to be updating input to the the IVRInput system, as old system has been deprecated. This involves creation an 'action manifest' to define application controller I/O events, which can then be bound to unique controls for each controller style.

https://github.com/ValveSoftware/openvr/wiki/SteamVR-Input