Wikipedia:Featured picture candidates/Day and night

Day & Night

Original - Gun and antigun in Day and Night cellular automaton.

Reason

I think this highlights the amazing patterns that can be created in Day and Night as well as highlighting the symmetric nature of the automaton. The colour scheme helps to highlight movement and the animation loops endlessly ending exactly where it starts so there is no jumping or jerking as the animation begins.

Articles this image appears in

Day & Night

Creator

--Simpsons contributor (talk) 02:30, 8 July 2009 (UTC)

• Support as nominator --Simpsons contributor (talk) 02:30, 8 July 2009 (UTC)
• Question Can you make the captions more descriptive? I don't really understand what's happening in the image... ZooFari 03:41, 8 July 2009 (UTC)
• Comment I do understand, but would prefer the image to be a bit larger - it's very hard to make out some of the details on any modern monitor if 1 pixel = one square of the automaton. Shoemaker's Holiday (talk) 04:16, 8 July 2009 (UTC)
• Comment I’ll answer both those questions: day and night is a 2D cellular automaton, an x-y matrix of discrete points that either alive or dead during on frame and are labelled as such. Each frame in the image represents a generation in which some cells die, some continue to live and some come to life. Day and Life works by the following rules: a living cell remains alive if 3,4,6,7 or 8 surrounding cells are alive and a dead cell comes to life if 3,6,7 or 8 surrounding cells are alive.

And I’ll produce a 2x enlarged image and upload it ASAP. I think more than 2x might produce a gif file that’s a bit too large. --Simpsons contributor (talk) 04:37, 8 July 2009 (UTC)

edit 1 Large (bilinear) version.

This is bilinear interpolation 2x. Do you think nearest neighbor interpolation (that would retain the square shape of each cell) would be more appropriate? --Simpsons contributor (talk) 04:52, 8 July 2009 (UTC)

• Comment First of all, i would like to say congratulations for another great animation. Then, I've got a couple of suggestions to improve the image. First, you need to explain your color scheme in the summary of the file. What does orange/green means ? Second, minor, thing : the anti gun is neatly defined inside a yellow box, but the gun isn't : it is too close to the left side of the image, and some things happens right next to the border, which may falsely indicate that some cells escape to the left. It would be better if you added a black border on the left. And now, here come the big one : I've some trouble figuring out how many structures are involved and what they do. For example, i can't figure out whether the tiny yellow structure on the right side of the light gun is a part of the gun (i.e. without it you can't create bullets), or another structure which is only here to change the period of the gun. Same thing for the dark structure with the same look. Moreover, i don't understand at all what happens at the interface between the light gun and the dark gun...I see that the dark bullet generate a green cell, and somehow that leads to the destruction of the light bullet, but the green thing doesn't seem to get close to the light bullet. In your GoL animation, you used colors to indicate different types of structure, but obviously you can't do it here. So we need to figure out a way to explain all this. If we don't, at least we could put it in the summary of the file. Ksempac (talk) 09:07, 9 July 2009 (UTC)

The string of images came straight from the Java program so there’s no way any cells escape to the left. The colouring scheme is as follows:

if(alive)
{
    if(liveCount == 3)
        newColor = new Color(255, 100, 0); (dark yellow)
    if(liveCount == 4)
        newColor = new Color(255, 130, 0);
    if(liveCount == 6)
        newColor = new Color(255, 160, 0);
    if(liveCount == 7)
        newColor = new Color(255, 190, 0);
    if(liveCount == 8)
        newColor = new Color(255, 220, 0); (light yellow)
}
                
if(!alive)
{
    if(liveCount == 3)
        newColor = new Color(0, 100, 0); (dark green)
    if(liveCount == 6)
        newColor = new Color(0, 160, 0);
    if(liveCount == 7)
        newColor = new Color(0, 190, 0);
    if(liveCount == 8)
        newColor = new Color(0, 220, 0); (light green)
}

So a cell that comes to life is yellow, the shade depending on how many neighbours it has. A cell that remains alive is green and again the shade depends upon the number of neighbours.

I got the pattern from the cellular automata program Golly. Here’s a description of the pattern according to its creator:

"This is a period 256 rocket gun which demonstrates the symmetry of the Day/Night rules, and how a signal can be sent across the border between day and night regions. Here a period 256 anti-gun destroys every other rocket from a normal period 128 rocket gun. Based on a reaction by Dean Hickerson. David I. Bell, May 1997"

Maybe this isn’t a fantastic explanation. If there’s anything that I haven’t made clear please tell me. --Simpsons contributor (talk) 06:09, 10 July 2009 (UTC)

edit 3 With edges left bottom and top.

Support Ok i get it. But we will have to explain all (colors, interaction between guns, periods, etc...) this in the summary of the picture. Maybe i will do it later. Still, you didn't understand me about the "cells escaping to the left". What i meant is that if someone doesn't know much about cellular automation, he may think that some cells escape on the left. It would be better with a black border on the left, in the same way there is a black border on the bottom that shows the limit of the anti-gun. Ksempac (talk) 12:43, 12 July 2009 (UTC)

Gotcha. I’ll produce a new image with a band of ten black pixels to the left and the bottom. Tell me what you think of it when I upload it. -Simpsons contributor (talk) 13:21, 12 July 2009 (UTC)

edit 2 With edges

I'd suggest top is necessary as well. Otherwise, inclined to Support Shoemaker's Holiday (talk) 20:12, 12 July 2009 (UTC)

As said above, Support edit 3 Shoemaker's Holiday (talk) 15:34, 13 July 2009 (UTC)

For some reason edit 3 isn’t showing. I assure you the top, bottom and left have edges now though! I’ll try and re-upload the image to see if I can solve the problem. --Simpsons contributor (talk) 06:08, 13 July 2009 (UTC)

I can see Edit 3 without problem. Maybe you should clear your browser cache. BTW I Support Edit 3 now.Ksempac (talk) 08:41, 13 July 2009 (UTC)

Not promoted No quorum. --wadester16 06:00, 16 July 2009 (UTC)