Geometry Maths?

Does anyone have a link about the vector math used in jME?



To be more specific: about (modifing) rotation of objects.

I understand the simple things like rotating an object around the x/y/z axes and so on.

And I can imagine what direction/left/up vectors mean.



I had vectors, matrices, and stuff like that in school as well as in my computer science studies. (called "Analytic Geometry" back then)

But i must confess i simply don't figure out how rotation matrices work in jME or what the .w coordinate of a Quaternion stands for :frowning:

And i don't have the slightest clue for what 4-dimensional matrices are needed in a 3-dimensional room

One of the best math books that will cover all of that (one that was used for much of the jME code) is:



Mathematics for 3D Game Programming and Computer Graphics

http://www.amazon.com/exec/obidos/tg/detail/-/1584502770/102-0005820-6308104


I want to make an object (i.e. a quad) always face the camera in a 90

Thanks mojo, just ordered that book. :)  Gonna read it over the weekend.



darkfrog

Hm thx for the answer, but i'm too spoiled by google to buy a book for things i can surely find somewhere in the web :smiley:

Besides, i don't need the whole thing from a to z, but only a few lines of explanation.



And for the billboardNode… i'll try it out, but this won't really solve my problem, as the 90

Well, I'm a professional developer, but have recently decided to make a major commitment in my spare time to learning game development and eventually make it more than a hobby, so I've got a bigger interest than most. :)  The more I can learn about 3d the better off I'll be.



darkfrog

Here’s a couple of good articles:

http://www.gamedev.net/reference/list.asp?categoryid=28



You may also want to check out this one:

http://chortle.ccsu.edu/VectorLessons/vectorIndex.html



Sometimes mathworld can be of help as well:

http://www.mathworld.com/



And I’ve had this book on my shelf for a while now:

Mathematics for Game Developers



I havn’t had the time to look into it that much, but it seems alright.

Thanks!  More information the better. :slight_smile:



One of these days I'll know enough to be useful. :wink:



darkfrog

Big thx! from me, too, Per.



This is exactely what I had in mind. Especially the gamedev.net link.

Happy to help :slight_smile: