On 2016-01-11 15:57, Kerry Mitchell wrote:
Here's one on a 2048 x 2048 grid, mod 1024:
http://www.kerrymitchellart.com/temp/moire.png
Kerry
Inverse motion blur!?! Fullscreen. Then the contrast increases dramatically, but only while scrolling. WtF? --rwg (MacBook Pro)
On Mon, Jan 11, 2016 at 4:02 PM, Dan Asimov <dasimov@earthlink.net> wrote:
Nice! Christian, I don't know if you take requests, but:
Would you be willing to do the same thing but with 1024 or more colors, on a larger square?
That will show the fine features of the Moire pattern more clearly.
(Also: The (x,y) coordinates should ideally refer to physical pixels of the computer, rather than virtual pixels; I'm not sure whether you already did it this way or not.)
—Dan
On Jan 11, 2016, at 9:55 AM, Christian Lawson-Perfect < christianperfect@gmail.com> wrote:
Here you go: http://checkmyworking.com/misc/dan-asimov-pattern.png I coded it up earlier today - http://codepen.io/christianp/pen/PZjGmV
On Mon, 11 Jan 2016 at 14:29 Fred Lunnon <fred.lunnon@gmail.com> wrote:
Does anybody have a link to a relevant pic?
WFL
On 1/11/16, Dan Asimov <asimov@msri.org> wrote:
Joerg's last e-mail reminded me of my first computer graphics experiment (1981), which I since learned that many other people have also tried:
----- Make a color table of N colors (labeled 0 through N-1) representing a discrete circle of hues. (One easy way to do this is to use the circle inscribed in the hexagon cross-section of the RGB cube [0,1]^3 that is halfway between black = (0,0,0) and white = (1,1,1). At that time the maximum I could use was N = 256 colors (equally spaced around the circle of hues).
Then for each pixel on the screen, with coordinates given by the integer point (x,y), calculate
C(x,y) := x^2 + y^2 (mod N)
and then color pixel (x,y) with the color having number C(x,y) in the color table. -----
The effect is an extremely complicated Moire-type pattern. I later used 1024 colors and the effect was even more interesting.
I have not seen any good explanation of the very complicated image that this produces. I also tried many other polynomials P(x,y) in lieu of x^2 + y^2, and got some weird results, but nothing was as interesting and I daresay beautiful as x^2 + y^2.
—Dan
On Jan 11, 2016, at 2:49 AM, Joerg Arndt <arndt@jjj.de> wrote:
Thanks. My impression is that imposing conditions mod something on x^2 + y^2 would . . . . . . . . .