This is a dat.gui controlled WebGL 2 tool for spherical reprojection of equirectangular images.
I thought it would be fun to hang a Ricoh Theta V under a kite, but I got nausea from the perspectives in a VR headset.
I needed a tool to bring the photographed horizon to the texture's equator and Simple 360 degree fov was there to help.
The Euler angle navigation is prone to Gimbal lock. Quaternions promise hope, but that's not yet implemented.
Perhaps Orbit Controls could be worth the challenge too. Your chance.
Nikolas Stausbøl from @evryone_XR, creator of Nickeldome, suggested a way to add exif data for sharing on Facebook.
I typically use this Windows command line tool with a batch file where you can drop image files on.
Drop your own equirectangular photos on this site and save reprojections of it, currently at a fixed size of 4096x2048 pixels.
Press X to toggle a grid overlay on and off.
Press Q or E to +/- increment angle1, keys A and D control angle2, W and S angle3.
Increment steps start with 0.1° accuracy but get wider the longer you keep the keys pressed.
Cursor arrow keys Left and Right switch between images.
The Up and Down cursor arrow keys change the projection method.
Chronologically, after equirectangular came the azimuthal projection collage.
Then came the stereographic projection. Both got a few more dat.gui controlled parameters.
d=0 is very near, d=1 gnomonic projection is a special case in the very center of the sphere, only d=2 is stereographic actually.
d > 2 is out of the sphere on the other side again. Like here but with a changed sign.
Press F11 for fullscreen and the space bar to shut this splainer box.