[osg-users] Side by side viewers with different field of view

[Steven Powers]

I have need a bit of a sanity check as I've been fighting with this all day.

I have two different applications that are rendering the same scene in parallel. The only difference is the projection matrix and viewports. I would expect both of these windows, when put end to end to match completely. The problem is that items in the scene are misaligned vertically but are aligned horizontally

Left camera has the following set:
	Viewport 0 20 640 400 
        Near 1
        Far 44000
        #frustum angles in degrees
        Frustum -14 14 -8.75 8.75
	#View Offset (these are offsets from the observer's position in degrees) 
	ViewOffset1 Rotate -28 0 1 0 

The right camera has the following set:
	Viewport 640 20 1280 400 
        Near 1
        Far 44000
        Frustum -28 28 -8.75 8.75	
	#View Offset (these are offsets from the observer's position) 
	ViewOffset1 Rotate 14 0 1 0 


I've attached a screenshot of the result. (I've cropped it a bit on the sides but you can clearly see the seam in the middle. This works completely fine when both left and right applications have the same FOV and viewport.

Does anyone know if settings like this should line up? Should they only work if the frustum angles match? I'd like to think that they would since they seem to line up perfectly on the horizontal but are flawed on the vertical.

What should I do to get them to line up?

Cheers,
Steven

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http://forum.openscenegraph.org/viewtopic.php?p=67659#67659




Attachments: 
http://forum.openscenegraph.org//files/fovdifference_161.jpg