Camera problem

[larztheloser]

Because I'm using windows to do my input I can't use the FPS or Maya camera classes.

What I've done is create a normal camera and made it float above a terrain. Then I made 4 global variables to store information about the camera's position: camx, camy, camz and camr (the last one being rotation). Then each frame I update the camera's position like so:

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camera->setPosition(core::vector3df(camx,camy,camz));
camera->setRotation(core::vector3df(0,camr,0));

It renders fine EXCEPT when camx, camy or camz are changing. What it does is focus on the last position the camera was in, until of course the camera stops moving. Turning the camera works fine. Moving and turning the camera, it turns right but the target of the camera is still wrong.

Any ideas as to why/how to fix this?

[larztheloser]

Sorry, I'll be even more descriptive of the problem.

Why does the camera tilt down when moving up, or up if moving down?
Why does the camera turn 180 degrees when moving forward?

[Epi]

maybe the camera is looking to its target, set by

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virtual void irr::scene::ICameraSceneNode::setTarget  	(  	const core::vector3df &   	 pos  	 )

[larztheloser]

I thought of that. But shouldn't that be handled by:

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cam->bindTargetAndRotation(true)

?
Thanks for trying!

[larztheloser]

Solved my own problem, I think.

For some reason, if you set the position, then render, then rotate, then update the absolute position, that works.

Can anybody tell me why? I'm confused - doesn't rendering the scene update the absolute position for me?

[CuteAlien]

If you use setTarget then it still has the old position. Calling updateAbsolutePosition after the setPosition will fix that.
If you only use setRotation and not setTarget then I'm not sure what the problem is.

My own camera code also looks like this (including comments):

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    mIrrCamNode->setPosition( camPos );
    mIrrCamNode->updateAbsolutePosition();  // don't remove - see comment below
    // setTarget will set also the rotation.
    // This only works if setPosition and updateAbsolutePosition are called first
    mIrrCamNode->setTarget( targetPos );
    mIrrCamNode->updateAbsolutePosition();

[larztheloser]

Yeah - I'm only using setRotation.

Thanks for that code snippet though!