Vector3f rotation methods?

[elias4444]

Ok, I'm tired of looking for help on this in regular openGL forums to only hear someone say, "just use such-and-such C++ math library" that I can't use with LWJGL. 

The problem: I'm setting up different types of bounding volumes. Specifically, let's talk about AABB. When you rotate something via glRotatef, it draws just right, but then you need to recompute the 8-points of the original bounding box and redetermine the max-min X, Y, and Z points. I have a method that works, but uses trig (lot's of Math.cos() calls). I've read that most people recommend using a transformation matrix to determine the new points instead, but I can't figure out how to do that in LWJGL.

I can setup a new matrix (via: new Matrix4f()), and rotate it (via: theMatrix.rotate(Math.toRadians(45), new Vector3f(1,0,0))). But I have no clue how to apply that matrix to my original point (contained as a Vector3f) to get a new, rotated Vector3f.

Could someone please post a code snippet for me?

Any help is appreciated!

[princec]

Simply multiply the matrix by the point to get the transformed point.

Cas

[elias4444]

Yeah, it's that "simply" part that gets me every time. 

So, how do you multiply a matrix4f by a vector3f? 

[elias4444]

Hey I found it!

Here's the answer... you CAN'T multiply a Matrix4f by a Vector3f!!!! BUT, you CAN multiply a Matrix4f by a Vector4f!!



Thanks for the help Cas!

[princec]

It's always the details isn't it

Cas