Camera position: Define camera position

The dialog defines a camera position within polar coordinates, a target point within model coordinates and a model orientation given by an up-vector. These parameters can be dynamically changed by sliders (using mouse or cursor keys).

Hint: dragging the pointer in the graphics window with the left button pressed can also dynamically change Angles Phi and Psi. Dragging horizontally will change angle Phi, dragging vertically will change angle Psi.

When altering the view the display lists aren’t freshly build, only the view is adopted. So a quick display can be reached. When moving the sliders, the view is immediately adjusted only if the option “Apply immediately” is checked. With complex graphics each altering of the view may require several seconds, in this case adjusting the view may be quickened with button “QV on” (see below):

The zoom angle and the distance of the viewpoint may also be given numerically. From the list also 8 camera position in the 8 quadrants of the coordinate system can be selected. To adjust the view the button “Apply” must be pressed. Button “Default” sets a default view in the first quadrant.

Following Dialog shows the available options:

Apply immediately

With this option set the graphical representation will be immediately actualized after a slider is moved. Disabling this option several parameters can be modified before pressing button „Apply“ generates a new plot.

Up-vector and reference point

Reference point (target point) is specified with x,y,z-coordinates in model space. Default is the center of the shown model. The sliders can move this point. The up-vector defines the axis of the coordinate system, which should be drawn upwards. Default is (0,0,1), i.e. z-axis upwards. In case the camera is positioned along the z-axis (Psi = 0 or 180 degrees), default up-vector will be (0,1,0) (y-axis upwards).

Up vector and reference point can also be given numerically in the input fields, updating is done after pressing button “Apply”.

Camera position

Phi: Angle of rotation within x-y-plane between -180^o and +180^o.

Psi: Angle of rotation measured from z-axis in the range of 0^o to 180^o.

Zoom: Angle of aperture in the range of 0.3^o (large) to 30^o (small). As numerical value can also be given in the input field.

Calculate distance: Pressing this button, a default distance between camera and target point is newly calculated. A new value can also be given in the input field.

X,y,z = d *: The list shows some predefined points for the camera position in the global coordinate system. After selecting one option the view is adjusted by pressing button “Apply”.

Default:

Pressing this button, the default view is newly applied.

QV on / of

This button allows a quicker finding of the optional view (QV stands for Quick View) in case the graphics is very complex as with shading or representation of scalar fields. The button functions as a switch and is alternately labeled „QV on“ and „QV off“. Switching QV on causes all currently visible display lists to be set invisible and a new list to be displayed that shows only the sharp edges of the selected elements. This reduced graphics can quickly be rotated or zoomed to find the desired view. After that QV is to be switched of with the same button and the full graphics will be visible again.

Save / Restore view

Pressing button “Save” the parameters of the current view will be stored, pressing button „Restore“ can later restore this view. Up to 4 different views can be stored; the number of view must be given in the input field.