Hello,

 

 I'm trying to merge two sub-graphs to the same image. It doesn't work so well, 
so I'll try to explain what in general I'm trying to achieve, then my not 
working so well solutions, and then the questions :-)

 

So, in general I want to replace an object (A) in the scene with another object 
(B) on some condition. The object (B) is some pixels which are lit up. The 
important thing is to keep the 3D scene distance from the camera for both 
objects, so if the object is obscured by another, then both (A) and (B) will be 
obscured, and if some other object (C) is obscured by (A), it will still be 
obscured by (B). Object (B) might be partially transparent.

 

Not working so well solution 1:

Have switch for (A)/(B).

The position of (A) is multiplied by view-projection matrix, the result is 
pos'. (B) is a set of points which their vertices are pos' with (x,y) replaced 
by the pixels I want to lit, and the new positions are multiplied by the 
inverse-projection invers-view matrices.

This solution had problems with setting the right pixels.

 

Not working so well solution 2:

Object (B) is a set of pixel under ABSOLUTE_REF orthographic projection with 
(x,y) of the pixels I want to lit and z is the negative distance between (A) 
and the camera.

This solution has the correct pattern of the lit pixels, but the Z order 
doesn't seems to be correct.

 

The implementation of solution 2 is to add camera with ABSOLUTE_RF and 
orthographic projection. View is identity. I set the clear mask to 0 since I 
don't want the Z-Buffer to be cleared. (opposed to huds and that kind of 
implementations). 

 

I used the osgviewer to put the cow at 0,0,-300 under absolute_rf, and a point 
at 0,0,0 under separate camera with orthographic projection, and the point was 
hidden by the cow (which is a mistake).

I thought that I might need to set the zNear/zFar of both camera's to be the 
same, but in this simple example it shouldn't matter since the point Z is zero…

 

So first, do I have to set the zNear/zFar of both camera's to be the same?

 

Any ideas whats going wrong?

 

Other solutions for the problem?

 

Btw, I tried to replace the points by quads under orthographic projection. The 
results were the same.

 

Thanks,

 Guy.

 

________________________________

מאת: [email protected] 
[mailto:[email protected]] בשם Robert Osfield
נשלח: Monday, March 16, 2009 5:39 PM
אל: [email protected]
נושא: Re: [osg-users] RecordCameraPathHandler where is the saved_animation.path 
file?

 

On Mon, Mar 16, 2009 at 3:28 PM, Felix Ilbring <[email protected]> wrote:

Hi Robert

I have done it. I put it to

new osgViewer::RecordCameraPathHandler("C:\\ETC.path");

but it was never there.


The class has always worked for me, so can't suggest any gotcha's, you'll have 
to open up a debug and see what the ReecordCameraPathHandler is doing on your 
build/system.

Robert.

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