math problem

[Blade]

I guess i have a mathematics problem but perhaps, there is a better way in Irrlicht to get what I want:

I want a aabbox3df to follow a scene node (not the bounding box). All i've got is a matrix4 where the rotation and translation of the node is stored. So i can get matrix4->getRotationDegrees() and matrix4->getTranslation().

Here is my code:

Code: Select all

void Update() // not an Irrlicht Update function
{
actmat.getTransformInformation();
lastmat.transformBox(physbox);
actmat.transformBox(physbox);
actmat.getInverse(lastmat);
}

I'm sure i get the right information because with this actmat matrix i also change the position and rotation of my scenenode.

I also tried to transform the MinEdge and MaxEdge vectors of aabbox3df but it didn't work either

[vitek]

The nodes bounding box does follow it around, provide that you transform it using the nodes absolute transformation...

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core::aabbox3df box = node->getBoundingBox();
node->getAbsoluteTransformation().transformBoxEx(box);
// box should be positioned where node is

If you have the rotation and position of a scene node, you should be able to do essentially the same thing..

Code: Select all

core::matrix4 m;

// it is safe to put a translate and a rotate into a matrix like this,
// just don't apply a scale
m.setTranslation(translation);
m.setRotation(rotation);

m.transformBoxEx(box);

Travis