Changing core

Troubleshooting General Help
1

First I want to thank the makers of JME for the engine. I have been using the old core for half a year. I am changing over to the new core of JME and have noticed made a few observations:


  1. There is no rotate pitch and rotate yaw in the new core like there was in the old. How can I convert the rotation from the old system to the new?



    2 The culling seams to be off. My MS Models are disappearing while they are still on the screen, and in between the near and far planes. (I am using a few week old CVS snapshot).
2
  1. Rotations are handled via rotational matrices or quaternions now. Usually, you’ll deal with quaternions, and a quaternion can be built in a number of ways. I’m most comfortable with an angle of rotation and an angle. For controlling a node or similar check out the code for the NodeController, that might give you some insights on how to go about setting the objects angle.


  2. This is a new problem, and it’s known now. It’s caused by mixing bounding volumes. And if you are using a model loader they are automatically setting their volumes to spheres (something that will be fixed soon), so you should be using spheres for any other nodes you have. Soon, you will denote the model bound of the models. Later, we will allow merging of multiple bounding volumes.
3

What is a quaternions how do I convert pitch and yaw to one. javascript:emoticon(’:?’)

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4

A Quaternion is another mathmatical way to describe rotation. See the following urls for some explanations:



history and theory:

http://mathworld.wolfram.com/Quaternion.html



practical usage:

http://skal.planet-d.net/demo/matrixfaq.htm#Q47



Also, please see the Quaternion class itself for various methods that may be useful to you, especially fromAngleAxis, fromAngles and fromRotationMatrix.