Orchid XP v8 wrote:
> Jim Charter wrote:
> 
>> On a whim I spent just a little time poking around with Google to 
>> investigate how difficult it would be to set up a virtual space with a 
>> viewpoint that can be zoomed, dollyed, and panned. This could be in a 
>> browser or in a separate viewer. At first blush it seems that panning 
>> the camera or rotating an object is easy, also zoom, but dollying the 
>> camera not so?  Is this true?  Does this function present a particlar 
>> hurtle that panning and zooming doesn't?  Google maps does it.  Does 
>> the difficulty increase linearly or exponentially?
> 
> 
> If you wanna look from side to side or turn around, you can just 
> manipulate a flat 2D image using 2D translations and rotations - just 
> make sure the edges line up to make a continuous visual. Zooming is a 
> similar story.
> 
> You want to *move* the camera position? Well then... *now* you must have 
> a *real* 3D environment. (After all, you need paralex and stuff. You can 
> fake that in 2D to some extent, but if arbitrary camera positions are 
> possible, there's really no way to avoid a full 3D environment.) 
> Obviously this is *significantly* more complicated to do.
> 
> Google Earth does it because it only draws a spherical planet. ;-)
> 
Okay, perhaps, but my findings actually assumed 3d in all cases.  For 
instance there are applets around which will rotate an object and zoom 
the camera.  Also on various forums there are little opengl engines that 
do same.  But for a game engine or something that would do like a game 
character walking through rooms,... that seems to be a much bigger deal. 
  Again, I apologise that I am only beginning to look into this.

The basic Google Maps gives an orthographic-like view with zoom and 
unconstrained movement.  The zoom also increases the resolution.  Also 
there is the 'street view' which is like the game thing where the 'car' 
drives along a constrained path and the viewer in the car can see 
panoramas at any point though the resolution is constant.

Google Earth is more like the camera in a modelling program with 
uncontrained movement, pan and zoom, with the added bit where it quite 
smoothly replaces low-res with high-res 'textures' as you zoom.

Roughly what I was dreaming of doing was to marry the type of drawn map 
info in Google Maps with the camera freedom of Google Earth, but without 
any of the sophisticated resolution adjustment in either presentation. 
All I was really envisioning was to control the movement of a camera 
around say a box with a diagram on it and maybe a coupla other boxes to 
mark buildings.  But rotating and zooming the object would be a little 
underwhelming without being able to dolly the camera too.  Because 
dollying a character through a game scene seemed such a common thing to 
do I was a little surprised at my initial findings.

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