Back to the drawing board; VU-3D for the TS2068. (evaluation) Owen W. Linzmayer.

For many in the computer world, the name Timex conjures up images of a tiny, black "toy." Timex Computer Corporation now has a larger, more expensive machine, the TS2068, and they are convinced that it is a powerful home computer. After experimenting with the hi-res graphics capabilities of VU-3D, a new cassette-based program for the TS2068, I must agree.

While not advertised as such, VU-3D can be thought of as a poor man's CAD (Computer Aided Design) package which allows the user to design, display, and print sophisticated three-dimensional "objects." Supplied on an autostart cassette, VU-3D was written by Psion Software and is being marketed in the U.S. by Games to Learn By.

While many software packages are touted as being user-friendly, VU-3D honestly is--you are never more than a key-stroke or two away from a helpful menu in VU-3D, and a list of available commands is always present on the screen. Your first option, after loading the main program, is to enter a data file from tape or begin to create your own figure. Unless you want to recall an item previously saved to cassette, you must choose the latter, which brings you to the "drawing board."

The drawing board is where all of the cut and paste work is done. Your workspace is set up on a cartesian coordinate grid with the origin (0,0) located in the lower lefthand corner. Above the drawing board is a thin banner in which the current commands are displayed, and at the bottom of the screen is a dynamic status line with such information as the cursor position. After leafing through the sketchy seven-page pamphlet that is supplied with VU-3D, you are adequately prepared to "build" your first object. Building An Object

Let's say, for example, that you want to create a rectangular box. Start off by pressing O to open the file which will contain your finished figure. A set of crosshairs pops up at the center of the screen. This is the cursor that you move around the screen using the arrow keys (5-8). After positioning the cursor where you wish to begin the base of the box, designate the starting point of the figure by pressing S.

The only thing currently on the drawing board is a single glowing point--not much to speak of yet. Slide the cursor over to the right and draw a line to that point. Move the cursor down again and draw another line. Once again to the left, and you have already drawn three sides of the box. To complete the base of the box, type E for end. This draws a line from the current position to the original starting point.

The rectangle displayed on the screen is the footprint of the object you are creating. That is, if you place the completed figure on a dusty desktop, the footprint is the impression left in the dust by that object.

If you want, you can reposition the base on the drawing board, or you can add another dimension by moving out to the next Z plane. Whereas the X and Y coordinates may be thought of as the length and width of the object, Z is its height. As you move out along the Z plane, you are extruding the box with you.

Unfortunately, there is no way to go backward along the Z plane--if you want to make changes, you must select the modify option from the main menu. When you decide that the box has been stretched out to the appropriate height, you may complete it with either an open or closed top, depending on whether you want to build a box or a block. You are now ready to go to the main menu by quitting.

The main menu has seven items (see Figure 1), but all you want to do right now is to see what you have made. The display option allows you to do just that. By pressing the various arrow keys, you can rotate the object in any direction. This in itself is a truly impressive feature. When the rotate keys are used in conjunction with the commands that let you magnify, reduce, and move the figure, you can view your creation from any angle, any distance, any perspective. At this point, your figure is only a set of connecting lines drawn by the computer. To make your object jump off the screen in an amazing display of 3-D realism, enter the picture mode. Adding 3-D

In the finishing stage, the tremendous capabilities of the VU-3D package become apparent. One option is to remove the hidden lines from your drawing, those that the viewer normally could not see from his particular vantage point (see p. 189, Feb. '84 for an excellent tutorial on hidden lines). Once done, you can go one step further and shade the figure by choosing the direction from which the light source will strike the object. This function can be repeated using different inputs until the desired effect is achieved. One shortcoming of this feature is that even if there is more than one object displayed on the screen at a time, the objects do not throw shadows on each other as you would expect them to in reality.

Up until this point, the figure exists within the memory of the computer as a complex string of zeros and ones; if the machine is turned off, your object disappears. To save your creation for posterity, you may print out a hardcopy if you have a printer connected to the TS2068, or you may keep it on tape. Unlike the save command that can be accessed through the main menu, this option saves the current picture screen to tape, not the original figure from which the picture was created. This static screendump can be loaded back into the computer via a Basic command and used by programs of your own design. Summary

While VU-3D is extremely flexible and easy to use, it isn't without its shortcomings. For one thing, there is no easy way to draw ovals, much less circles. For another, instead of using a "repeat figure" command, you must painstakingly replicate each figure if you want similar objects on the screen at the same time. Finally, when the objects number more than a few, or become too complex, the rotate command is a little bit slow. This is more of a gripe than a valid complaint--after all, how much can one expect of a $200 computer anyway?

Make no mistake about it, VU-3D is a program that struts the stuff of the TS2068. Aside from the hours of fun you can have simply dreaming up exotic shapes and figures, VU-3D proves an invaluable tool for budding artists and geometry students as well as those involved in mechanical drawing pursuits. I strongly recommend VU-3D; the right hemisphere of your brain will thank you.

Products: VU-3D (computer program)