Smooth transition between 2d and 3d

[ahocevar]

Idea: A la google map, share the bottom line and tilt. Forward and Backward.

Some thoughts about the camera movement: https://gist.github.com/tonio/750dbc843ef95601c4be (might be outdated with the experience of the following POCs)

Ongoing work:

• 1. POC: http://bl.ocks.org/tonio/raw/9759909/
• To be developed further: http://bl.ocks.org/gberaudo/raw/51f050326d91d4e9c09a/1b55ad64a1f3de2dcba5673ecb52f976104a4592/#

Remarks:

• all directions must be handled (not just NS and EW);
• all tilted situations must be handled (starting from an arbitrary tilted angle);
• always keep center of bottom line fixed in general, whole line for NS and EW.

[klokan]

It seems the diagram shows rotation around fixed center point with (an optional?) variable distance of camera:

This may be quite easy to do right now with camera from #8 - just to implement animation with setTilt() and setDistance() calls. All directions (NS, etc) should be handled automatically by OLCesium.

If the implementation should be more closer to what is visible if clicking on Tilt control or switch to maps in Google Maps WebGL globe:
https://www.google.com/maps/@24.5168465,0.2099982,69709a,20y,71.85t/data=!3m1!1e3
Then the diagram is wrong, because the center poing should be moving significantly and altitude of camera should be fixed.

Google Earth plugin integrated with Google Maps V2 had a different animation I think.

[gberaudo]

Indeed, Google Map V2 behaviour seems to do a simple rotation around the bottom line center. As a consequence, the intersection of the camera direction with the terrain is moving in the direction of the horizon. It is this transformation which we want to implement.

[klokan]

Do you have a demo with Google Maps V2 online to have it here?