I present the range of screen captures on this page as an introduction to the types of graphics that the Commodore Vic-20 computer was capable of.

Title screen from a game written in BASIC that came with the computer. There is a nice display of colour bars top and bottom of the screen. Note that the screen is really just an array of rectangles that could be filled with one of a wide range of characters (that were all designed to fit within each rectangle).

Typical screen seen while playing this game, which was written using BASIC, on the Vic-20. Note the basic structure of the graphics, based on a grid of characters, like the text screens.

Vic Avenger is a commercial cartridge game. You turn the computer off, attach the cartridge to the special port on the back of the computer, and then turn the computer back on. The computer then automatically starts up showing the screen shown above. This behaviour was typical of attaching most cartridge games. This screen shows a variety of small characters produced for this game, presented on a white screen of mainly text. The character graphics look quite professional, and seem to take up 2 or 3 characters (each character being 8 pixels by 8 pixels) worth of space.

The small characters as they appear in the game, with characters making up shapes for the disintegrating barriers, and bullets.

Sargon Chess is another cartridge game. The graphics used in Sargon Chess gave it a professional feel, and the game play was excellent. I can even remember using the game to solve some of the chess problems presented in one of the daily newspapers.

The screen cycles between showing the effects of pressing the "A" key, the "D" key, "F1" key, "F3" key and the "F5" key. The "pressed" keys are displayed as black, and the effect is shown on the image of the lander (in this case, pressing the "D" key operates a small thruster rocket on the right that will push the lander to the left).

The small lander is influenced by a gravitational pull. You have to apply main thruster amounts to stop it from dropping too quickly, and use the sideways thrusters to line up the lander to land safely on one of the 3 landing pads shown.

As the lander gets close to one of the landing pads, the game shows a magnified view of the region around the landing pad, and allows for finer control over the lander. Here, I have landed on the "x10" landing pad successfully. The green gauge on the right shows the black needle in the yellow zone (required for a successful landing). The value obtained from the landing is then added to your score, and fuel supply. It is a very well written game that gives a good sense of the gravitational pull and use of the thrusters.

This graphic was produced by a commercial program. I corrected the aspect ratio of the image as displayed on the Vic-20 - very impressive graphic, using the basic colour available from the Vic-20!

Here, you can get an idea of how BASIC program listings appear on the Vic-20 screen, though they typically went on over many screens of code. The BASIC interpreter is a very sophisticated program. Editing can be achieved in a number of ways. One way is to use the cursor keys to put the cursor over a previously listed line of code, and type corrections directly over the top. After pressing the return key, the line is then updated to this new line of code. You can easily add lines by typing a line number and entering code. Lines are automatically ordered according to their line number. In the example above, if I wanted to add some code between lines 520 and 525, I could just type 522 and add some BASIC code. When I ask the computer to list lines from 520-525, it would list all 3 lines in proper sequence. The logic and mathematical calculations available from the computer are marvellous.

I remember enjoying playing SubLogic's Flight Simulator on my brother's Commodore 64. It gave the user access to the main flight instruments of a Cessna C182 or similar. There were 3D views and a sense of moving through 3D space.

I knew I didn't have the computing resources to recreate such a program on the Vic-20, but I attempted a simpler type of program - one that would hopefully give me a sense of flight from a flight model moving through a vertical plane only, and by applying control over thrust, and elevator angles. I produced the image of the control panel (with stall warning, engine tachometer, air-speed indicator, altimeter, elevator position indicator, a rise or fall indicator, and a fuel gauge) and wrote the drawing of the gauge hands in machine code for speed. The program did give a sense of flight, especially with the ability to get off the ground and into the air, but the flight model used was not very subtle, and laboured under the lack of processing speed.

SpeedScript 3.2 is a word processor written by Charles Brannon for Compute! Magazine (April 1985). It was written in machine code, and entered byte by byte from the listing in the magazine, using a utility called MLX, which made the manual entry of the program more reliable, and able to be done in multiple sessions.

SpeedScript 3.2 had a number of useful functions, such as word wrapping and entry of printing escape codes for specifying bold text, page widths, tab widths, etc. (which made more sense once the document was sent to a suitable printer). The software displayed text in upper and lower case, and showed various formatting codes, such as carriage returns, etc. The software worked well with the Epson dot-matrix printer I purchased, and allowed me to write many of my written assignments for my degree, from the comfort of home. I eventually modified some of the key combinations used, to reflect those used in leading word processors, and added a basic spell-checking function (comparing each written word from the word processor with a set of around 500 words loaded (then held) in my specially made 40K Vic-20 memory configuration [5 lots of 8K RAM, selectable using a software block selector]).