Provide access to detailed rendering logs

[exbluesbreaker]

Is your feature request related to a problem? Please describe.
It would be great to be able to access verbose rendering logs to profile/analyze performance.

Describe the solution you'd like
I was debugging some graphical issues and I saw at least on vtk side vtkTimerLog is used for logging, at least being able to retrieve data from it can be helpful. Also maybe some additional log on a side of F3D can be also useful.

Describe alternatives you've considered
For now I was manually analyzing using debug prints.

Contribution
I think I could work on it. At least work on basic implementation at first.

[mwestphal]

Can you explain what you have in mind in more details ?

I fail to see how vtkTimerLog would help, its merely a start/stop counting timer.
You can put it anywhere to measure performance but I dont think we want to instrumentize the whole code with it.
Especially as most of the rendering/interaction stack is in VTK, not in F3D.

[exbluesbreaker]

Can you explain what you have in mind in more details ?

I fail to see how vtkTimerLog would help, its merely a start/stop counting timer. You can put it anywhere to measure performance but I dont think we want to instrumentize the whole code with it. Especially as most of the rendering/interaction stack is in VTK, not in F3D.

Maybe it is not relevant. I was basically concentrating a lot of on rendering durations while investigating animation freeze issue. While issue wasn't with render taking too long, but events related to rotation of scene and related rendering flooding and not letting animation update and related rendering.

In general I just saw some timer timestamps logging or something on VTK side in some of the rendering methods I was debugging through. So I though maybe it could be retrieved in some kind of debug build on F3D side. I will second check my observations there.