Added option to blit on camera PostDraw

[rickyviking]

Added the option to blit the mirror camera on the Oculus Right eye camera PostDraw callback rather than swap callback. This allows other cameras rendering in POST to draw after the texture blit, allowing for instance to visualize osg stats.

See attached image for the OsgOculusViewerExample with the stats enabled (I think the huge update time is just due to the viewer waiting for the next swap buffer, saturated at 80Hz by the Oculus SDK).

[bjornblissing]

If my memory serves me correctly Oculus advised against assuming that the eyes were rendered in a specific order. But maybe this have changed?

[rickyviking]

It might well be as you remember, but that applies to how the Oculus SDK renders to the device, i.e. after submitting the frame to the Oculus SDK in the swap callback. The 2 osg cameras instead are rendered in a specific order (left and right), see: https://github.com/bjornblissing/osgoculusviewer/blob/master/src/oculusdevice.cpp#L221 So, after the right eye camera has been rendered by osg, the frame which will be sent to the Oculus in the swap callback is complete and should be OK to blit it to the mirror texture.

[bjornblissing]

closed by 0e9e521679d5ba62d8e3f7bfdcbe7ce8ebff7913