openspace command convention

Quick note to self - when we want to use the built-in fadeIn or fadeOut commands, we can't use the name of the object as seen in the info tab - like Scene.Moon here,

We will get errors like
Error when calling script 'openspace.fadeIn': Could not find property 'Scene.Moon.Enabled'

Checking the script log, we need to append .Renderable to that name, like

openspace.fadeOut("Scene.Moon.Renderable", 5)

tumblerd prevents disk from being ejected on Linux

When trying to eject a USB external disk, a message along the lines of "process tumblerd is currently using the disk, eject anyway?"

https://duckduckgo.com/?q=what+is+tumblerd+which+is+keeping+disk+from+being+ejected+on+linux&ia=web

Since I had a very large number of images on that drive, and I had just saved an mp4 file onto the drive, tumblerd was probably creating thumbnails for all of the multimedia files. So, did 

killall -HUP tumblerd

and then the disk could be ejected.

OpenSpace session recording "save frames" crash

On my Lenovo ThinkCentre M93 machine with an NVidia GTX1050 graphics card, OpenSpace session recording playback with "save frames" was crashing after a few hundred frames being saved. Each frame was taking around 1000 to 1500 ms for 4096x4096 frames.

According to Claude.ai, the crashes might be due to CEF "being starved" between updates - and I submitted this fix as an issue on the OpenSpace repo.

Claude suggested workaround was in SGCT.

// sgct/src/image.cpp

png_set_compression_level(png, -1);  // changed to:

png_set_compression_level(png, 1);

As the comment just above that line says, -1 sets the compression level to default, which seems to be 6. Setting this to 1 made the frame export only 300 ms per frame (3x faster) and also fixed the crashes - so CEF was not "being starved" of updates.

The increase in file size was not much, 4 MB increased to 5.1 MB for a typical frame.

Another change I made before exporting again, was to close all other windows and apps like the Edge Browser, which I had used earlier for triggering the exports - now OpenSpace has some checkboxes in the export settings which allows us to hide the UI while exporting, so we don't need to trigger the export via a web browser.

Edit: No, the problem is not solved. No crash when saving frames for this recording, ts_003_moon_to_Earth.osrectxt

but crashes after a few hundred frames when saving frames for this recording, ts_002_india_rotate_zoom.osrectxt

So my current workaround was to split the recording into multiple smaller recordings.

downloading from a server via http (no SSL) with auth

Downloading some planetarium files from a server in Sweden, which had password protected directories but no SSL (no https) - 

1. Directly downloading via the browser - slow, prompts us to "Keep" or delete the file every time due to being downloaded unsecurely
   
   
2. Using aria2 - 
   
    aria2c -x16 -s16 --http-user=USERNAME --http-passwd=PASSWORD url
   
   Need ProtonVPN, since without it, http downloads are severely throttled to less than 100 kbps.
   
   
3. Better option, running 
   
   aria2c -x16 -s16 --http-user=USERNAME --http-passwd=PASSWORD -i urls.txt
   
   on one of our AWS servers - all the URLs get downloaded in a jiffy, then we can use Filezilla and download to our local machine over sftp without throttling issues.