The "Normal" is a direction that points directly away from any surface. Typically, the "normal" direction is represented by a Vector (a collection of x, y, and z values). For example, if the floor of your room is in the X-Y plain, then the normal direction will be along either the +Z or -Z direction -- straight up or straight down. In this case you get to choose which direction is considered the "normal" direction. If you chose "up" then the Normal Vector would be x=0, y=0, and z=1 ... also written as <0, 0, 1>. If you chose "down" then the Normal Vector would be <0, 0, -1>. The direction you choose is important because sometimes Java3D will only draw the surfaces with Normals pointing toward the viewer instead of away. For example, if you choose the "up" direction above such that the floor's Normal Vector was <0, 0, 1> then Java3D would draw the floor for viewers standing on the floor, but anyone on the floor below would not see it when they looked up -- if would look like there was no ceiling because the Normal Vector was pointing away from them. To see the ceiling you would need a second surface with a Normal pointing down.
-Todd J.
Jasmine Kwok wrote:
Hi,
Can someone kindly give me a brief explanation of what is a normal in a GeometryArray? The J3D API doesn't help. Thank you!
Regards, Jasmine
=========================================================================== 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".
