| 3-D Visualization | |
This section discusses the individual camera motion functions selectable from the toolbar.
| Note When interpreting the following diagrams, keep in mind that the camera always points towards the camera target. See the Defining Scenes with Camera Graphics section in this chapter for an illustration of the graphics properties involved in camera motion. |
Orbit Camera rotates the camera about the z-axis (by default). You can select x-, y-, z-, or free-axis rotation using the Principal Axis Selectors. When using no principal axis, you can rotate about an arbitrary axis.
Graphics Properties. Orbit camera changes the CameraPosition property while keeping the CameraTarget fixed.
Orbit Scene Light
The scene light is a light source that is placed with respect to the camera position. By default, the scene light is positioned to the right of the camera (i.e., camlight right). Orbit Scene Light changes the light's offset from the camera position. There is only one scene light, however, you can add other lights using the light command.
Toggle the scene light on and off by clicking on the yellow light bulb icon.
Graphics Properties. Orbit Scene Light moves the scene light by changing the light's Position property.
Pan/Tilt Camera
Pan/Tilt Camera moves the point in the scene that the camera points to while keeping the camera fixed. The movement occurs in an arc about the z-axis by default. You can select x-, y-, z-, or free-axis rotation using the Principal Axes Selectors.
Graphics Properties. Pan/Tilt Camera moves the point in the scene that the camera is pointing to by changing the CameraTarget property.
Move Camera Horizontally/Vertically
Moving the cursor horizontally or vertically (or any combination of the two) moves the scene in the same direction.
Graphics Properties. The horizontal and vertical movement is achieved by moving the CameraPosition and the CameraTarget in unison along parallel lines.
Move Camera Forward and Backwards
Moving the cursor up or to the right moves the camera towards the scene. Moving the cursor down or to the left moves the camera away from the scene. It is possible to move the camera through objects in the scene and to the other side of the camera target.
Graphics Properties. This function moves the CameraPosition along the line connecting the camera position and the camera target.
Zoom Camera makes the scene larger as you move the cursor up or to the right and smaller as you move the cursor down or to the left. Zooming does not move the camera and therefore cannot move the viewpoint through objects in the scene.
Graphics Properties. Zoom is implemented by changing the CameraViewAngle. The larger the angle, the smaller the scene appears, and vice versa.
Camera Roll
Camera Roll rotates the camera about the viewing axis, thereby rotating the view on the screen.
Graphics Properties. Camera Roll changes the CameraUpVector
Walk Camera
Walk Camera moves the camera in the direction of the camera target and moves the camera target by the same amount. It also pans the camera from side to side. Walk Camera enables you to move the camera through the scene, passing through objects that lie along the viewing axis.
Walk Camera is somewhat analogous to driving a car while keeping your eyes pointed straight ahead. As you turn to the right, the objects in the scene move off to the left.
Walk Camera is best used when viewing axis lies in a plane that is perpendicular to the principle axis. For example, if Z is the principle axis, then you should position the camera at the same Z value as that of the camera target (you can do this using Orbit Camera). The toward or away motion then stays at a constant Z value. You may find it useful to zoom out before using Walk Camera.
Graphics Properties. Walk Camera modifies both the CameraPosition and the CameraTarget, preserving the distance between them.
| | View Control with the Camera Toolbar | Camera Graphics Functions | |
