Camera Manipulation

Each MFC window has a separate HOOPS camera that may be manipulated to change the current view of the model. The camera operations implemented are:

  • Orbit

  • Pan

  • Zoom

  • Walk

These are modal operators on the view and are chosen by toggling the camera manipulation modes in the Standard Toolbar or selected as an option in the Manipulation menu. Once a camera manipulation operator has been selected, the camera may be interactively manipulated with the mouse. All operators respond to the following sequence: left mouse button down, left mouse button down and moved (motion), left mouse button up.

The Orbit Operator allows for panning and zooming without switching operators. To pan, hold down the [SHIFT] key while dragging the mouse. To zoom while in orbit mode, hold down the [CTRL] key while moving the mouse. In addition holding down the middle (or third) mouse button while over an object will orbit the camera around the selected point.

At any time double clicking the middle mouse button will either zoom to the object under the cursor or (if no object is under the cursor) will reset the camera to the scene extents.

The Walking operator allows the camera to be moved “inside” the scene. By Pressing the left mouse button and dragging the mouse forward or backward the camera moves along the current view vector on the ground plane. Dragging the mouse left or right rotates the camera around its up-vector. Holding down the middle mouse button while dragging strafes the camera up/down and left/right without changing the rotation. Finally using the mouse wheel the camera can be tilted up and down.

In the Manipulation menu, you will find that the Smooth Transition option is on by default. When this feature is turned on, the camera will smoothly transition producing animation effect when user zooms to window, changes the view plain or resets camera. You can toggled this feature on and off.