The normal is calculated as the cross product of two vectors, and is anti-commutative. That means
aXb is not equal to bXa (where X stands for the crossproduct operator) If you're not familiar with vector math, think of ; 'a' as being the side of a triangle (vector) from vertex 0 to vertex 1 'b' as being the side of a triangle (vector) from vertex 0 to vertex 2 you can find the direction of the cross product (or normal) with the right hand rule. If you change the order of calculating the crossproduct, you find the direction with your left hand rule. If none of this makes sense, Here's a link that goes into more depth; http://members.tripod.com/~Paul_Kirby/vector/Vcrossproduct.html#findnormal regards, Peter =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff JAVA3D-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
