Remove camera calculations once OpenUSD/#2556 is fixed

[hybridherbst]

usdrecord should already calculate bounds and clipping, however there seems to be a bug with small objects where clipping planes aren't set correctly:
PixarAnimationStudios/OpenUSD#2556

Once that is fixed, the code here can be simplified (e.g. camera calculations could be optional if more control is needed).

[hybridherbst]

This one seems to be fixed now:

• usdrecord: empty output for files that are visible in usdview PixarAnimationStudios/OpenUSD#2556

Might be worth a try and

• either remove custom camera calculations from this repo
• or report an issue with what doesn't work with the usdrecord calculations

[beersandrew]

This one seems to be fixed now:

• usdrecord: empty output for files that are visible in usdview PixarAnimationStudios/OpenUSD#2556

Might be worth a try and

• either remove custom camera calculations from this repo
• or report an issue with what doesn't work with the usdrecord calculations

usdrecord by default does frame the subject well, not sure in which cases this was not working in the past. but the one factor here is that usdrecord is taking the image as if it's being seen for the first time in usdview. this usdview camera is not square so i think for the purposes of thumbnails there still needs to be camera logic to frame the subject and adjust field of view to produce a square view of the subject. this makes me think there isn't anything to change here. let me know if that makes sense or if you had some other ideas for this issue.