Calculate field of view based on aspect ratio?

[dkirkby]

From @kfanning:

I noticed it seems to have a fixed FoV regardless of the aspect ratio, leading to weirdness when viewing vertically on a phone but better horizontally.

Next steps:

• [x] reproduce the problem
• [x] figure out whether the pannellum FoV is horiz or vert or something else
• [x] calculate desired FoV based on window dimensions
• [x] implement an event handler for changes of window dimensions

[dkirkby]

The pannellum library assumes a fixed horizontal FoV independent of the window width, which leads to a jarring change in FoV per pixel when rotating between portrait and landscape on mobile devices.

The solution I implemented is to generate the initial view with a fixed FoV of 0.09 deg / pixel, then track changes to the FoV initiated by the user (via zoom in/out), and preserve the current pixel FoV during window resize events.

So far I have only tested this in a chrome browser on a Mac.

[kfanning]

Tested with firefox on android rotating the phone as well as firefox on a laptop resizing the window and the new behavior feels consistent when changing aspect ratio (either through rotation or resizing) and has less distortion in vertical aspect ratios.

[dkirkby]

This seems to be working well - closing now.