176 x 224 pixels, created using a Vic-20 computer.

The Vic-20 computer was advertised as a colour computer, and you can see from the graphics produced for the commercial games on the second page of this display, that the Vic-20 is capable of producing some graphics in simple colours. I decided to try to write a program for producing coloured screens based on ‘painting’ character blocks. Each character block was 8 pixels wide by 8 pixels high. I found that I could produce a good working screen size that was 22 characters across, by 28 characters high (a little bigger than the standard text screen of 22 characters wide by 21 characters high). I found that the computer can use one of 8 basic colours (black, white, red, cyan, green, magenta, blue, and yellow) for colouring each character. There was a separate colour (1 of 16 simple colours including the 8 colours used for the character colours) that could specify the colour of the underlying screen. The colour of the surrounding border could be specified from the 8 simple colours listed earlier for the character colours.

I worked out a way of moving a cursor around the screen using the keyboard, and devised my own character patterns to provide some ‘mixing’ of character colours with the screen colour, etc. I experimented with a whole range of aspects to do with the program in an effort to improve the visual possibilities that the Vic-20 computer could provide.

176 x 224 pixels, created using a Vic-20 computer.

This is a fairly simple design, but quite effective. I added a function to the program to take the character and colour under the cursor and reproduce it along the whole horizontal line of the image. I added a similar function to take the colour and character under the cursor and reproduce it through the whole vertical line of the design.

176 x 224 pixels, created using a Vic-20 computer.

Here, I was trying to use the basic colours available, in a combination that taps into the emotions.

176 x 224 pixels, created using a Vic-20 computer.

Piet Mondrian painted many amazing abstract designs based on sharp straight orthogonal black lines (running horizontal or vertical) and rectangular areas of flat primary colours. I found that my “Tone Paint” program could be used to produce similar types of images.

176 x 224 pixels, created using a Vic-20 computer.

Piet Mondrian painted many amazing abstract designs based on sharp straight orthogonal black lines (running horizontal or vertical) and rectangular areas of flat primary colours. I found that my “Tone Paint” program could be used to produce similar types of images.

176 x 224 pixels, created using a Vic-20 computer.

Mark Rothko’s abstract paintings often consisted of rectangular ‘fields of colour’ that were designed to trigger special emotions from their relationships with the background colour.

176 x 224 pixels, created using a Vic-20 computer.

I wanted to see if I could use the gamut of available colours in my program to create an image that felt as though it was from a desert. I then thought about trying to indicate a bright sun, and wanted to include some rectangular window shapes of solid colours.

176 x 224 pixels, created using a Vic-20 computer.

Looking at ways to get more colour combinations on the screen, I found that if I set a character to appear using a special ‘multicolour mode’, then an auxiliary colour (1 of the 16 colours used to specify the screen colour) could be used within the design of the characters, along with the border colour. The trade-off with the multicolour character designs was that pixels were now twice as wide as that for non-multicolour characters.

A range of non-multicolour characters can be seen on the right hand side of the screen. Non-multicolour characters can only have one of eight character colours over a screen colour (in this case ‘light red’). Non-multicolour characters can use pixels that are an eighth of the width of a character, creating more even textures.

In regions of 8 x 8 characters on the “Tone Paint” screen, I could ‘paint’ the patterns using the 4 colours available in multicolour characters (character colour [red], screen colour [light orange], auxiliary colour [white] and screen border colour [black]) that I thought might result in good multicolour characters. I then added those multicolour characters to my program.

176 x 224 pixels, created using a Vic-20 computer.

I programmed the rendering of the colour wheel in this image using the new multicolour characters. I then added the available non-multicolour characters and other multicolour characters to the edges of the image to get a sense of the available colours I now had in my painting program - quite impressive really! And this was the collection of colours using a screen colour of ‘light red’, an auxiliary colour of white, and a screen border colour of black. I could also now see the effect of changing the screen colour, the auxiliary colour and/or the screen border colour on the available colours for an image.

400 x 255 pixels, created using Adobe Photoshop Elements.

I blurred the image “Colour Wheel using Multicolour Mode” using Adobe Photoshop Elements, to get a better sense of the colours/tones that are part of my program’s gamut of available colours (trying to remove the visual effects from seeing the patterns of contrasting individual pixels). I was quite impressed with the available possible colours. Obviously, the biggest deficiency was the lack of colours that lie on the colour wheel between the main 6 colours of yellow, green, cyan, blue, magenta and red.

176 x 224 pixels, created using a Vic-20 computer.

Here, I set up logical sequences of gradients that use multicolour characters over the whole screen. It makes quite a complex pattern overall, but also feels quite rich.

176 x 224 pixels, created using a Vic-20 computer.

After setting up a screen of sequences of red gradients over the whole screen, I applied a screen ‘mirror’ function, that reflects the top left corner of the screen to the top right corner and then reflects the top half of the screen to the lower half of the screen. The result is rather pleasing.