Drawmode property of lines

There was some interest a while back about graphics and how to get rid of a drawn line.

There are 16 line drawmodes. I wrote a miniprogram to find out what they all did. The program drew a line; then drew another one over it to see if it cancelled it. I tried all 16 modes for the 'cancelling' line. ('Cancelled' means 'cancelled', not just erased. So the original line had to be drawn over a picture to make sure that the picture ;returned unimpaired when the drawn line was removed.)

I found that what these DrawModes did partly depended on the colour used for the original line drawn in default mode 13. With a red line (&H000000FF&), or a blue line (&H00FF0000&;) the only cancelling DrawMode which made it invisible was 11. But with a black line (&H00000000&) DrawModes 3, 7, 11, and 15 all made it invisible.

Useless information ? Probably, especially if you all knew this anyway. If you didn't, it might just be worth filing for future reference.

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