2.2 Constructing a cube
In the following example the most important functions are presented and explained:
There are two completely different approaches to get a cube: You can construct it, or you
can just set the coordinates of eight vertices. The second possibility is easier for the
- Generate eight free points by double-right-clicking into the scene.
- Set the coordinates of the points by ’right-click - settings’ on the names of the points
in the list or by using the context-menu ?settings?. Use the coordinates (0, 0, 0), (5, 0,
0), (0, 5, 0), (5, 5, 0), (0, 0, 5, (5, 0, 5), (0, 5, 5), (5, 5, 5). Right-click here:
Enter the coordinates and press ok:
It should look like this:
Tip: You can navigate in the dialogue with the TAB-key.
- Alternatively the points can be entered in the command line directly. The input for
this would be ’A=(0,0,0)’, ’B=(5,0,0)’ and so on.
- Now you have to construct the sides of the cube. As those are square, you can use the
built in parallelogram.
Three vertices have to be selected for a parallelogram. The order is important: The
middle point is the apex of the angle between the first and the third point. Example:
If you select the points in the picture in the order P2, P1, P3, you get the following
If you use the order P1, P2, P3 instead, you get:
- The finished cube should look roughly like this:
Now you can brighten up your cube by changing the colors in the parallelograms context
If the buttons are not hidden (menu Extras - settings - view - show buttons) you
can change several colors simultaneously: Select the items you want to change by
shift-clicking into the scene and click on the color-button.
At the same time you can set the objects transparency. This can be done in the
context-menu or with the spin-box ’transparency’.
Alternatively, you can group the sides of the cube (select the sides, choose Extras -
Group objects) and adjust the color for the group-object.
In the end, the cube could look like this: