Eric Weeks - personal pages - computer-generated pictures computer generated black and white pictures

weeks/physics.emory.edu

Click here to return to the explanation of how these pictures are generated, otherwise the explanations on this page won't make much sense.

Normally I would use the direction of the arrow to choose the color, with say 0 degrees=white, 180 degrees=gray, 360 degrees=black. Suppose I use 0=white, 90=gray, 180=black, 270=gray, 360=white. This produced the picture above -- now the defects are intersections between black and white lines.

This picture was made mapping 0,180,360 degrees to white, and 90,270 to black. Thus the intersections between white and black lines are the defects, and along white lines the arrows are all pointing left/right, along black lines the arrows are all pointing up/down.

The above-left picture, I'm not sure how I made. I was fooling around on 'xv' (a good graphics manipulation program which is available for linux computers, I'm not sure about otherwise). The above-right picture was made mapping 0,90,180,270,360 to white; 45,135,225,305 to black; and gray in between.

Links...

• Questions? Comments? Send me email; email address below.
• Research I do
• Other pictures I've made - quasicrystals, fractals, cellular automata, other things.
• Software I've written -- some functional, some fun
• Various simple algorithms for making simple pictures
• Graphics techniques (some used to make this picture)