Segregation and Other Intolerant Algorithms [Lasercut Screen]
./wp-content/uploads/sites/2/2013/10/output1.pdf
Drawing loosely from the Nervous System presentation, I began thinking about processes I could exploit to churn out varied, yet unified designs. While searching for information about laplacian growth, I found this pithy sketch by echoechonoisenoise on OpenProcessing, which employs a grid of automata to generate a segregation pattern.
My cells are similarly situated in a grid, wherein three main processes occur. First, a matrix of cells is seeded by a scaled noise field, which is in turn refined and restricted using the modulus operator and a threshold. This design is problematic out of the tube, since the laser cutter wants lines and not filled blobs.
![](https://i.imgur.com/S5iEasZ.png)
So the second step is to use a neighbor-counting technique similar to echoechonoisenoise’s to isolate the border of the blob shapes. (If a cell has three out of eight possible neighbors, I can assume with some confidence that it is a bordering cell.) Third, to convert a set of disparate points to vector lines, I plot lines from each cell to the nearest available living cell.
Disclaimer: I try to produce smooth-ish lines in a relatively straight-forward fashion, but I admit that there are instances of weirdo trickery in my code:
import processing.pdf.*;
float cells[][];
float noiseScale = 100.0;
float scaleFactor = 1;
int dist = 3;
//density of pattern
int bandWidth = 1200;
//noise seed
int seed = 9;
int[] rule = {
0, 0, 0, 1, 0, 0, 0, 0, 0
};
int searchRad = 12;
int cellCount = 0;
void setup() {
size(900, 900);
cells = new float[width][height];
generateWorld();
noStroke();
smooth();
beginRecord(PDF, "output.pdf");
}
void generateWorld() {
noiseSeed(seed);
//Using a combination of modulus and noise to generate a pattern
for (int x = 0; x < cells.length; x++) {
for (int y = 0; y < cells[x].length; y++) { float noise = noise(x/noiseScale, y/noiseScale); if (x % int(bandWidth*noise) > int(bandWidth*noise)/2) {
cells[x][y] = 0;
}
else if (y % int(bandWidth*noise) > int(bandWidth*noise)/2) {
cells[x][y] = 0;
}
else {
cells[x][y] = 1;
}
}
}
}
void draw() {
background(255);
drawCells();
//Draw the world on the first frame with points, connect the points on the second frame
if (frameCount == 1) updateCells();
else {
for (int x = 0; x < cells.length; x++) {
for (int y = 0; y < cells[x].length; y++) { if (cells[x][y] > 0) {
stroke(0);
strokeWeight(1);
//Arbitrary
for (int i = 0; i < 20; i++) {
PVector closestPt = findClosest(new PVector(x, y));
line(x * scaleFactor, y * scaleFactor, closestPt.x*scaleFactor, closestPt.y*scaleFactor);
}
}
}
}
endRecord();
println("okay!");
noLoop();
}
}
//Finds closest neighbor that doesn't already have a line drawn to it
PVector findClosest(PVector pos) {
PVector closest = new PVector(0, 0);
float least = -1;
for (int _y = -searchRad; _y <= searchRad; _y++) {
for (int _x = -searchRad; _x <= searchRad; _x++) {
int x = int(_x + pos.x), y = int(_y + pos.y);
float distance = abs(dist(x, y, pos.x, pos.y));
if (x < 900 && x > 0 && y < 900 && y > 0) {
if (distance != 0.0 && (cells[x][y] == 1) && ((distance < least) || (least == -1))
&& cells[x][y] != 2) {
least = distance;
closest = new PVector(x, y);
}
}
}
}
cells[int(closest.x)][int(closest.y)] = 2;
if (closest.x == 0 && closest.y == 0) return pos;
else return closest;
}
//If the sum of the cell's neighbors complies with the rule, i.e. has exacly 4 neighbors,
//it is left on, otherwise it is turned off. This effectively removes everything but the
//outlines of the blob patterns.
void updateCells() {
for (int x = 0; x < cells.length; x++) {
for (int y = 0; y < cells[x].length; y++) {
cells[x][y] = rule[sumNeighbors(x, y)];
if (cells[x][y] == 1) cellCount ++;
}
}
}
int sumNeighbors(int startx, int starty) {
int sum = 0;
for (int y = -1; y <= 1; y++) {
for (int x = -1; x <= 1; x++) {
int ix = startx + x, iy = starty + y;
if (ix < width && ix >= 0 && iy >= 0 && iy < width) {
if (cells[ix][iy] == 1) {
if (x != 0 || y != 0) sum++;
}
}
}
}
return sum;
}
void drawCells() {
loadPixels();
for (int x = 0; x < cells.length; x++) {
for (int y = 0; y < cells[x].length; y++) {
int index = (int(y*scaleFactor) * width) + int(x*scaleFactor);
if (cells[x][y]==1) {
pixels[index] = color(255);
}
}
}
updatePixels();
}
void mousePressed() {
saveFrame(str(random(100)) + ".jpg");
}