Vector angle calculations, basic test package

[FortressBuilder]

Changes

• Added angle and angleCos methods to Vector classes. These return the angle and the cosinus of the angle, respectively, of two vectors. The angle is in radians.
• Added static negate methods to Vector classes.
• Removed the commas from and added whitespace to the Quaternion and AngleAxis toString methods (so they are consistent with the Vector and Matrix classes).
• Added org.joml.test package with some simple test classes. At the moment only angle is tested.

Issues

• The angle method in the Vector classes returns the angle in radians. However, I did see some methods that took degrees in their parameters. I decided to let the user choose whether they want to have it in radians or convert it to degrees. Is this correct? Which angle unit system should I use?

[httpdigest]

Thank you for your additions!

[FortressBuilder]

Thanks for including them! However, regarding the issue above: Should I use radians or degrees on further changes?

[httpdigest]

Regarding degrees vs. radians:
You are right, the angle parameters of most methods use degrees.

This is debatable, but was chosen for two reasons:

• to be compatible with the semantics of GLU and GL functions
• most typical angles in rotate() and the field-of-view in perspective() specified by the user can use "typical"/"nice" degree values, such as rotating about 90 degrees or having a field-of-view of 45 or 60 degrees, instead of using fractions of PI (or having to do Math.toRadians)

However, methods which return angles should use the "mathematical" variant of radians in order for those results to be chained to other methods also operating with radians.
But we must make it very clear in the JavaDocs that this is the case.

[FortressBuilder]

Okay, thanks. Maybe this should be added to the Design wiki page as well.

Edit: What about overloaded methods? perspective using degrees and perspectiveRad radians?