How to access model normals in "world space"?

[gamebeavis]

I was curious how to access a models vertex position and normals translated into world space. Basically, if I load a model into irrlicht, and perform an animation, rotation, and translation I dont think the actual mesh data changes, just the view of it does or does it actually change? If it dosnt, how do I access the vertex/normal data in its changed form?? If it does change I suppose I can just read that data directly from the mesh buffer of the node??

[bitplane]

the data held in the mesh buffers doesn't actually change, just the position which it is rendered from. so if you want a vertex position in world space, you have to transform the position by the model's absolute transformation matrix:

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node->getAbsoluteTransformation().transformVect(tempPosition)

normals are a unit vector that holds a direction rather than a position, so it makes no sense to translate or scale them. so just rotate them instead:

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node->getAbsoluteTransformation().rotateVect(tempNormal)

[omaremad]

btw this will only yield valid normals if you dont scale your model, scaled models need to use the inverse transpose of the model matrix.