# Option to choose shape and projection

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.

Hi Hyper,

We just added an orthographic projection option accessible via a new widget in the upper right if you have the time to do some testing: #5021

Patrick