#532 Prevent Screen Distortion on multi-monitor setups

[simon wood]

At present a single OpenGL viewport is used, which has the problem that on very wide screens the items in the perpherial vision are distorted.

I'm using a screen size 3840x1024, using the glance left/right I can see that the front wheels of an open-wheeler are getting rendered too large as I 'turn my head'.

I believe that this is caused by the single viewport, in that it is a flat plan infront of the camera. When items are drawn they are projected onto this 'screen' and as they are closer they are projected back and enlarged.

A solution might be to split the rendering into 3 (or however many) viewports, one for each monitor, where the frustum angle is adjusted to suit the monitor setup.

[simon wood]

Figured out my error in how the offset should be applied, this might actually be correct now.

Checked in r5164

[simon wood]

Put a 'before and after' video on YouTube to show how much better this makes the view from the driver's seat.

http://www.youtube.com/watch?v=OSZ3Pq8b4cU