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*zor*
06-30-2008, 05:53 AM
gluLookAt( GLdouble eyeX,
GLdouble eyeY,
GLdouble eyeZ,
GLdouble centerX,
GLdouble centerY,
GLdouble centerZ,
GLdouble upX,
GLdouble upY,
GLdouble upZ )

can you explain me what "center" and "up" are? please don't use technical expressions because beginners don't understand that :(

it is enough if you tell me how to look at a 3D object from exactly the top of it.(with angle of 90)

thx

dletozeun
06-30-2008, 06:11 AM
http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/glu/lookat.html

center is the target of your camera, and eye is the center of the camera

*zor*
06-30-2008, 06:14 AM
thx but i don't understand what "up vector" is : /

Zengar
06-30-2008, 06:32 AM
Up vector is wgere the top of yur head looks at :) Imagine it liek this: when you have a camera, you can rotate it around it's view vector (the eye and the target point are the same!). The up vector explains this rotation. Usually you want the camera head to look "up".

*zor*
06-30-2008, 06:44 AM
hmm

can we say that eye-up states the direction of our head and center is the actual place that we want to look?

thank you very much if i understand correcty
and if i don't, still thank you very much :D

dletozeun
06-30-2008, 07:25 AM
SOrry I read too fast, I forgot the up vector...

can we say that eye-up states the direction of our head and center is the actual place that we want to look?
Yes, you can think that the up vector is the vertical rotation axis of your neck when you do a camera panning movement.

*zor*
06-30-2008, 07:34 AM
thx thx thx :)