COMPUTE!’s Gazette – Volume 1 – Issue 1 – July, 2025

Arto Heino

Welcome to the Texas Instruments Roundup, your monthly source for the best of the TI world! This month, we’re diving into the creative side of the TI-99/4A with a powerful set of graphics routines from developer Arto J. Heino. Get ready to turn your TI into a canvas with XB-DRAW/99, a full-featured drawing program written entirely in Extended BASIC.

A Drawing Suite from 1986

Originally written by Heino back in 1986, XB-DRAW/99 is a fantastic example of what can be achieved with clever BASIC programming. Instead of relying on specific graphics modes, Heino designed his program to use the standard character set. Why? This ingenious approach allowed him to easily incorporate his line drawings into other Extended BASIC programs and games.

The program includes a complete array of useful graphics subroutines that are easy to follow and modify. The centerpiece of the article is the full type-in listing, allowing you to bring this powerful tool to life on your own TI-99/4A.

What Can It Do?

XB-DRAW/99 is more than just a simple plotting program. It’s a suite of routines that give you a remarkable level of artistic control:

• CALL PLOT: The core of the system, this assembly routine (loaded from DATA statements) is what all the other routines rely on to place characters on the screen.
• CALL LINE: Draw straight lines between any two points on the screen.
• CALL CIRCLE: Create perfect circles and ovals of any size and ratio.
• CALL DRAW: This powerful command allows you to draw complex shapes using a simple string of commands, like “move right 5 pixels, move up-and-left 3 pixels.”
• CALL THREEDIM: Explore the world of 3D by generating a variety of line graph functions.
• CALL JOYDRAW: Get hands-on with your art! This routine lets you draw freely using a joystick and can even be used to trace photos and other hand drawings. Heino includes a sample trace he made from a photo of himself back in 1985.
• CALL DUMP: Once your masterpiece is complete, this routine lets you print it out on an Epson-style dot matrix printer.

The article provides a detailed breakdown of all the variables and commands, giving you everything you need to start experimenting. This is a perfect project for anyone looking to learn more about graphics programming in Extended BASIC or just have some creative fun with their TI-99/4A.

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Read the full story and discover more about the world of retro computing in the first issue of COMPUTE!’s Gazette in 35 years!

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