revo(1)

NAME
revo - creates revolved 3d surfaces

SYNOPSIS
revo

DESCRIPTION
revo is an interactive Inventor program for creating 3d objects by drawing a curve and then revolving it around an axis.

The program has two main viewing windows: the curve view and the 3d rendered view. To create a object, click the left mouse button in the curve view near the default blue line. Hold the button down and continue to move the mouse, the point will be dragged. You can drag existing points on the curve by clicking and dragging. To delete a point from the curve, simply click the point to select it, and then press the BACKSPACE key to remove it.

As you draw the curve in the curve view, the 3d object is automatically draw in 3d in the other view. The 3d rendered view allows you to view your masterpiece by clicking and dragging in the view. Experiment with the various mouse buttons to gain control over the viewing. Press the right mouse button in the 3d rendered view, and select the `Functions/Help' entry for more help on 3d viewing.

Revo allows you to sketch out a line which is then rotated around an axis to form a surface of revolution. The left-hand window allows you to edit the line, and the right-hand window lets you view the resulting surface.

Initially, a very simple surface of revolution is shown; a single line segment is rotated about the vertical axis to form a cylinder. To add points onto the end (bottom) of this cylinder, just click the left mouse button where you want the new point to appear. To move an existing point, just position the mouse near the point (a small cross will appear), then press the left mouse button and drag the point to its new position. When you are satisfied with its location, release the left mouse button. You can also insert points in the middle of a line segment by placing the mouse near the segment, pressing the left mouse and dragging the new point to the desired location.

The Clear button below the main windows is an easy way of deleting all the points. You can also use the Backspace or Delete keys on the keyboard to delete points. The Copy button will copy the shape you have created to the Xt clipboard. You can then paste the shape into an Open Inventor application that supports paste, like the SceneViewer (revo does not support paste). You can change the number of sides used in the surface of revolution by typing into the #sides Motif text widget.

Normals are calculated automatically whenever the line changes. If the angle between two segments is small enough, a "smooth" normal will be generated. If the angle is too great, a "crease" will be automatically generated. Putting two consecutive profile points at the same location is another way of generating sharp creases. To save your objects you must first copy them to an application (such as the SceneViewer) that supports save. The 3d view is a standard Open Inventor Examiner Viewer. Press the right mouse button for a menu that will allow you to turn on the Examiner Viewer decorations, change drawing styles, and get help. This program is a lot like the revolve demo program, which was written using only the Iris GL. This program is approximately half the number of lines of code as the GL version, and has more features (e.g. changing the number of sides of the surface, copy to the Xt clipboard, the different drawstyles supported by the Examiner Viewer). No GL calls are made in the source code to this program, only Inventor calls (which uses Open GL).

Number of sides
    This number sets the number of sides the object will have around the revolution.

Copy
    Will copy your object onto the X clipboard, where it can be pasted into another Inventor program (e.g., showcase, SceneViewer).

Clear
    Removes your masterpiece and starts over again.

About
    Displays a short description about revo.

Quit
    Exits revo. Note that the data copied to the X clipboard with the copy button will disappear when revo exits, so be sure to paste your creations before exiting.

SOURCE CODE
Note that the source code to revo comes with the Open Inventor 3d Toolkit.

FILES
/usr/share/src/Inventor/demos/revo/* - Source to revo

SEE ALSO
SceneViewer, drop, gview, inventor, ivview, maze, noodle, qmorf, showcase, textomatic