/* built with Studio Sketchpad: 
 *   https://sketchpad.cc
 * 
 * observe the evolution of this sketch: 
 *   https://studio.sketchpad.cc/sp/pad/view/ro.sfu6HMlcMHo/rev.1512
 * 
 * authors: 
 *   Zach Denton

 * license (unless otherwise specified): 
 *   creative commons attribution-share alike 3.0 license.
 *   https://creativecommons.org/licenses/by-sa/3.0/ 
 */ 



// This sketch builds on a prior work, "Undulating Pixel Grid", created by Zach Denton
// http://studio.sketchpad.cc/sp/pad/view/ro.9lU9zD6n-JpSi/rev.366

// See also: http://en.wikipedia.org/wiki/Rule_30

int width = 100;
int height = 100;
int cell_width = 5;
int[][] grid = new int[height][width];
color alive = color(random(50), random(255), random(255), 100);
color dead = color(200);

void setup() {
    background(dead);
    // size(width * cell_width, height * cell_width); 
    size(500, 500);
    smooth();
    noStroke();
    reset();
    grid[0][(width / 2) - 1] = 1;
    update();
}

void update() {     
    // don't start processing until a live cell is found
    seen = false;
    for (int y=0; y < height; y++) {
        for (int x=0; x < width; x++) {
            if (x > 0) {
                left = grid[y][x-1];
                if (left > 1) {
                    left = 1;
                }
            } else {
                left = 0;
            }
            
            if (x < width - 1) {
                right = grid[y][x+1];
                if (right > 1) {
                    right = 1;
                }
            } else {
                right = 0;
            }
            
            center = grid[y][x];
                    
            pattern = str(left) + str(center) + str(right);
            
            if (pattern == '111') {
                next = 0;
            } else if (pattern == '110') {
                next = 0;
            } else if (pattern == '101') {
                next = 0;
            } else if (pattern == '100') {
                next = 1;
            } else if (pattern == '011') {
                next = 1;
            } else if (pattern == '010') {
                next = 1;
            } else if (pattern == '001') {
                next = 1;
            } else {
                next = 0;
            }
            
            if (y < height - 1) {
                grid[y+1][x] = next;
            }
        }
    }
}

void reset() {
    for (y=0; y < height; y++) {
        for (x=0; x < width; x++) {
            grid[y][x] = 0;
        }
    }
}

void draw() {          
    if (mousePressed == true) {
        mousePressed();
    }
    for (int y=0; y < height; y++) {
        for (int x=0; x < width; x++) {
            if (grid[y][x] >= 1) {
                strokeWeight(2);
                fill(255);
                stroke(alive);            
            } else {
                noStroke();
                fill(dead);
            }
            rect(x * cell_width, y * cell_width, cell_width, cell_width);

        }
    }
}

void mousePressed() {
    if (mouseButton == LEFT) {
        x = int(mouseX / cell_width);
        y = int(mouseY / cell_width);
        if (grid[y][x] == 0) {            
            grid[y][x] = 1;
        } else {
            grid[y][x] = 0;
        }
    } else if (mouseButton == CENTER) {
        reset();
    } else {
        update();
    }
}