From: Bruce S. <ba...@an...> - 2001-08-18 02:43:33
|
There are three different attributes of a display that affect the camera position: center the point in the scene that the camera is pointing at forward the direction that the camera is pointing (toward center) fov field of view The negative of scene.forward is a vector pointing from scene.center toward the camera. The distance of the camera from scene.center is determined by the field of view. The larger the field of view, the closer the camera is to scene.center; the distance is inversely proportional to scene.fov. I don't understand the comment that "Setting scene.center and scene.forward to their initial conditions (after a mouse-move) does not put the camera back at [0,0,3] ..." When I do this, it does in fact restore the camera back to [0,0,3]. Bruce Sherwood --On Monday, August 13, 2001 16:14 -0400 Gary Strangman <st...@nm...> wrote: > Is there _any_ way (direct or indirect) to specify the exact position of > the camera in 3D coordinates? Apparently the camera orientation can only > be changed with scene.center, but how about the position? The > scene.mouse.camera attribute is read-only, so the doc says to change > scene.center and scene.forward to change the camera position. While the > camera position does change when I change those 2 controls, I still have > been unable put the camera where I want it (e.g., to put the camera back > where it started prior to a user mouse-zooming around). > > Perhaps this is related to the fact that I don't understand how the camera > is positioned in the first place. At the bottom of this e-mail I've > attached a very simple example that shows where the camera is located as > one mouse-zooms around. Why does the camera start at [0,0,3]? And how, > after some zooming, could I put it back there? Setting scene.center and > scene.forward to their initial conditions (after a mouse-move) does not > put the camera back at [0,0,3] ... |