Classic Computer Magazine Archive CREATIVE COMPUTING VOL. 9, NO. 1 / JANUARY 1983 / PAGE 268

Drawart. (program for graphics on the TRS-80) Brad Pitzel.


The TRS-80 is not a great graphics machine, but with the help of the following short program, you can easily create some amazing displays. Drawart is a masterpiece in simplicity.

No longer do you have to sit down and plot each pixel that makes up a circle. Nor do you need to figure out the equation of a line just to draw it.

Drawart takes care of these problems and more. By using one-letter commands and the cursor control keys. Drawart makes your TRS-80 do all the tedious work; leaving you more time to be creative.

The commands are as follows:

Cursor Control: Pressing one of the arrow keys will move the cursor in the driection indicated on the key. You can't press more than one key at a time.

Draw/Erase Mode: The cursor in Drawart can be set in either the draw or erase mode. Pressing the spacebar reverses the current mode.

Lines: To enter the line mode, press L. Once you are in this mode, you must plot two points by using the spacebar and the arrow keys. Press G and these dots will be connected by a straight line in the order in which they wer plotted.

Roctangles: Pressing R places you in the rectangle mode. By using the cursor control keys and the spacebar, plot two dots. After you plot the second dot, the computer will fill in the area between the two dots.

Circles: Press C to enter the circle mode. Plot two dots that have the same Y axis. The first point is the center of your circle and the second designates the radius.

Block Move: To store the ASCII values of the entire screen into the memory addresses 26000 to 27023, press P. You can then continue drawing.

Table: Figure 1.

Table: Figure 2.

Table: Listing 1.