Volume series flickers in VR when Model Panel shown

[goddard@…]

The following bug report has been submitted:
Platform:        Windows-10-10.0.17134
ChimeraX Version: 0.91 (2019-07-25)
Description
Playing volume series in VR using the play series hand controller mode has lots of flicker when model panel is shown because model panel is constantly updating shown buttons and there are 600 models (300 volumes and 300 volume surfaces).  This data set has 4 channels, 74 time points.


Log:
UCSF ChimeraX version: 0.91 (2019-07-25)  
© 2016-2019 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  

> open
"C:\\\Users\\\goddard\\\Desktop\\\CD2RFP_MacBlue_B4649_BiTEsA488_ReducedStack.tif"

Opened multichannel map series
CD2RFP_MacBlue_B4649_BiTEsA488_ReducedStack.tif, 4 channels, 74 images per
channel, grid size 388,246,12, pixel 1.06,1.01,4, shown at step 1, values
float32  




OpenGL version: 3.3.0 NVIDIA 398.35
OpenGL renderer: GeForce GTX 1070 with Max-Q Design/PCIe/SSE2
OpenGL vendor: NVIDIA Corporation

[Tom Goddard]

Model panel gets a trigger notification any time a model display state changes, then updates the table after frame drawn trigger fires. When it updates the table it sets model colors, names, shown state, selected state for all models. This apparently is pretty time consuming for 600 models when only a few have changed, some being hidden and some being shown.

Playing through this volume series of 4 channels x 74 time points the first time creating surfaces takes 33 seconds with model panel shown and 13 seconds with Model Panel hidden. During this first play through 4 new surfaces are created on each of 74 frames. This adds a new model and so the entire model panel tree widget is rebuilt, which is probably more expensive than when just display state changes.

Eric improved model panel to only do the update after a certain number of frames where no changes were made. This fixes both the initial computation of surfaces and the VR hand mode playing through the series -- giving performance nearly the same as if Model Panel is hidden. In the VR case testing showed that the display checkbutton did update if the hand controller is moved slowly, but this did not cause troublesome flicker in the VR.

[Tom Goddard]

Fixed by Eric's changes.