Needed: Placeholder for NORTH to maintain direction

[AntiochInteractive]

The tutorial for setting up a radar on v3.0 showed a manual process of finding north, then using the user information field to store it. With this solution, we could use the placeholder $ui to get our north value. v4.0 provides the ability to set North from the Viewing Parameters screen, but does not provide us the ability to get the value with a placeholder.

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A placeholder is needed like $ap to return the pan value for north, and a placeholder to return the offset from north ($apNorth - $ap).

http://gardengnomesoftware.com/wiki/Skin_-_Placeholder

This will allow us to automatically pan to the correct direction when jumping scenes.

If North is at 90 degrees... and we're at 135 degrees -- we set the 'target' field to 45 degrees (that's the offset).
Then we open the next pano @ 45 degrees, and on init, add THAT pano's $apNorth to the current pan.... and then we are facing the correct direction every single time.

[Tong]

good point with auto hotspots set, when we activate hotspot in hotspot editor auto set fov and view angle using north from it and corresponding of node to open panorama.

right now we set it manually or used default for node view, good will be have autofill with ability correct it of course.