Maybe instead of 1 group of radio buttons (CV,2D,3D)
CV: Earth surface rendered on a 40 mega-meter wide 20 mega-meter high rectangle using a perspective projection.
2D: Earth surface rendered on a 40 mega-meter wide 20 mega-meter high rectangle using a orthographic projection.
3D: Earth surface rendered on a 6,378,137 meter major radius x 6,356,752 meter minor radius Ellipsoid (not warped like on a rectangle)
There could be 2 groups of radio buttons:
Shape: Ellipsoid or warped onto a rectangle
Projection: Orthographic or Perspective.
This would open up a 4th option of viewing the Ellipsoid with a orthographic projection. Also it might be a little less confusing this way.
I don’t know why pitch is fixed at -90deg and roll at 0deg in 2D mode for setView, as altering pitch can provide some interesting views:
CV can show terrain, why not 2D? Ya without the pitch option it would be pointless, but not if you could alter the pitch.
observations and thoughts regarding orthographic:
-If you only change the range to what you’re looking you will not see any changes while in orthographic projection.
-However changing altitude while pitch isn’t vertical will cause the view to shift.
-FOV should be interpreted as distance between the left and right frustum planes while in orthographic projection (while in perspective its the angle between)
-One can’t tell if the world is over them tilting downward or if the world is under them tilting upward!
-Orthographic is great for showing a very long skinny area where each part is shown the same as opposed to perspective where close items are large and far items are small.
I see that the rectangle size was not randomly chosen:
26,378,137PI = equatorial length ~= 40 Mega-Meters which explains the width of the rectangle.
Latitude covers half the degrees of Longitude (180 vs 360) which explains why the rectangle height is half of its width.