Colour Attributes

by Paul Lay


Issue 20

Mar/Apr 86

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NOTE: This program uses the routine from PICLOADA (in this issue). PICLOADA must therefore be merged with this listing by LISTing lines 10 to 630 of PICLOADA to disk with LIST "D:<filename>",10,630 and then, after having LOADed Attributes, using ENTER "D:<filename>".

This program takes Atari Artist pictures and allows each colour register to be changed (or attributed) on every scan line thus producing a picture with many more colours than normally available. The program is controlled with the Touch Tablet.

When the program is RUN, you will be given a list of available commands and prompted for a picture filename. Enter the filename and the picture will be loaded. By using the Touch Tablet in port #0 you can now control a cross-hair cursor which you may move about the screen. Move the cursor so that it is on a certain colour and hold down any Touch Tablet button. By moving the stylus around this colour is varied from the position of the cursor to the bottom of the screen. When the desired colour is displayed, release the button and the colour will remain set.

Note, as the colour is changed from the cursor position downwards, a top-down approach should be taken when colouring pictures.

There are five functions which are accessed by the key presses indicated.

[L] ...Load attributes

[S] ...Save attributes

[R] ...Random fill

[B] ...rainBow fill

[N] ...New picture

Load and Save store and recall the attributes to disk with the picture filename plus the extender .ATB.

The two fill commands affect the next colour selected by replacing it with either a random or rainbow pattern. New restarts the program so that a new picture can be worked on (don't forget to save any previous work first).

Finally note that the cross-hair cursor is a player graphic controlled by strings and it is important that the strings are DIMensioned in the correct order. If you have any problems LIST the program out to disk, re-boot and ENTER it to clear the variable table.