revo - creates revolved 3d surfaces
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
Page 1 Release 6.5 August 1991
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
Copy Will copy your object onto the X clipboard, where it can be pasted
into another Inventor program (e.g., showcase, SceneViewer).
Removes your masterpiece and starts over again.
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.
Note that the source code to revo comes with the Open Inventor 3d
/usr/share/src/Inventor/demos/revo/* - Source to revo
SceneViewer, drop, gview, inventor, ivview, maze, noodle, qmorf,
Page 2 Release 6.5 August 1991 [ Back ]