Problems rotating model - ardor3d

Engines, Libraries and Tools
#1

Alright, so I’m trying to rotate a model, and I got front and back down:
Back:

ReadOnlyMatrix3 tempM3 = new Matrix3(1,0,0,
												 0,1,0,
												 0,0,-1);
			colladaNode.setRotation(tempM3);

Front:

ReadOnlyMatrix3 tempM3 = new Matrix3(1,0,0,
												 0,1,0,
												 0,0,1);
			colladaNode.setRotation(tempM3);

But when I tried to do the sides:

ReadOnlyMatrix3 tempM3 = new Matrix3(1,0,0,
												 0,1,0,
												 0,0,-0.5);
			colladaNode.setRotation(tempM3);

or

ReadOnlyMatrix3 tempM3 = new Matrix3(1,0,0,
												 0,1,0,
												 0,0, 0.5);
			colladaNode.setRotation(tempM3);

it doesn’t seem to work. my model still faces back or front.

Any idea why?

#2

Google rotation matrices http://lmgtfy.com/?q=rotation+matrices, or look at the available methods in the ReadOnlyMatrix3f class (it probably has utility functions mentioning euler angles or something like that).

In brief, your first matrix is flips the z-axis, which resembles a rotation but isn’t really. Your second matrix is the identity, so it’s not doing anything, and your other ones are not valid rotation matrices, they are scaling the z coordinate and flipping its sign.