tienminhphan
Community Member
Posts: 7
|
 |
« on: September 24, 2009, 09:27:28 AM » |
|
I have a big problem with my program.In fact, Someone can explain to me the orientation in truevision? for exemple, the nature of the axes Ox,Oy,Oz!!! Because I see that They are not orthogonal! I mean they're not natural(Ox,Oy,Oz in right hand). And what're the positive orientation due to Ox,Oy,Oz!!
Excuse-me for my english
Thanks so much!!
|
|
|
|
|
Logged
|
|
|
|
jviper
Community Member
Posts: 2130
Discipline in training
|
|
« Reply #1 on: September 24, 2009, 01:19:16 PM » |
|
In TV3D, the X axis points to the right, the Y Axis points up, and the Z axis points forward.
|
|
|
|
|
Logged
|
JAbstract.....Don't just imagine, make it happen!
|
|
|
tienminhphan
Community Member
Posts: 7
|
|
« Reply #2 on: September 25, 2009, 02:50:15 AM » |
|
Jviper,as you say, Three axis in TV3D follow to the rule of right hand? X is the thumb, Y is the index finger( forefinger) and Z is the middle finger??,
Thanks so much!
|
|
|
|
|
Logged
|
|
|
|
jviper
Community Member
Posts: 2130
Discipline in training
|
|
« Reply #3 on: September 25, 2009, 10:48:51 AM » |
|
Actually, I beleive it would be more like the left hand rule, where thumb is right, index finger is up, but the middle finger points forward (away from you), rather than backward (toward you).
|
|
|
|
|
Logged
|
JAbstract.....Don't just imagine, make it happen!
|
|
|
|
Aki
|
|
« Reply #4 on: September 25, 2009, 12:04:42 PM » |
|
It might be more helpful to imagine 3d orientation as a piece of graph paper (x is horizonal, y is vertical) and then imagine the z axis as going in and out of the paper, adding depth. The positive x and y values are the same as it would be on graph paper, and positive z is towards you.
|
|
|
|
|
Logged
|
|
|
|
jviper
Community Member
Posts: 2130
Discipline in training
|
|
« Reply #5 on: September 25, 2009, 01:29:31 PM » |
|
positive z would be pointing away
|
|
|
|
|
Logged
|
JAbstract.....Don't just imagine, make it happen!
|
|
|
tienminhphan
Community Member
Posts: 7
|
|
« Reply #6 on: September 25, 2009, 04:13:14 PM » |
|
Thank you so much for your answer!!
So, someone can explain to me, when I turn from x to y around z, this is positive or not?
And anothers orientation? x ->y around z, y->z around x, and z->x around y??
|
|
|
|
|
Logged
|
|
|
|
jviper
Community Member
Posts: 2130
Discipline in training
|
|
« Reply #7 on: September 25, 2009, 07:48:46 PM » |
|
hmmm,
Around the -z axis
+x -> +y, +y -> -x, -x -> -y, -y -> +x would all be positive
+x -> -y. -y -> -x, -x -> +y, +y -> +x would all be negative
Around the +y axis
+x -> +z, +z -> -x, -x -> -z, -z -> +x would all be positive
+x -> -z. -z -> -x, -x -> +z, +z -> +x would all be negative
Around the +x axis
+y -> +z, +z -> -y, -y -> -z, -z -> +y would all be positive
+y -> -z. -z -> -y, -y -> +z, +z -> +y would all be negative
Careful though. Just because an object appears to be facing foward does not mean it is facing forward. It depends on how the model was modelled and what the model artists believes to be the front of an object.
|
|
|
|
|
Logged
|
JAbstract.....Don't just imagine, make it happen!
|
|
|
tienminhphan
Community Member
Posts: 7
|
|
« Reply #8 on: September 28, 2009, 01:14:42 AM » |
|
Thanx so much Jviper!!!
|
|
|
|
|
Logged
|
|
|
|
|
