Plotter Art: Oscillators in 3D 20171222

oscillatorsIn3D20171222.pde

/*
Oscillators in 3D 20171222
 by Jacob Joaquin
 
 email:     jacobjoaquin@gmail.com
 twitter:   https://twitter.com/JacobJoaquin
 instagram: https://www.instagram.com/jacobjoaquin/
 */

import processing.pdf.*;

// User variables
boolean doGeneratePDF = true;  // Create a PDF file?
int nPoints = 8192;            // Resolution of path
int nRotations = 16;           // Number of rotations of path
float o = 800;                 // Dimensions offset, bi-polar, [-o, o]

// Internal variables
ArrayList<PVector> path = new ArrayList<PVector>();
ArrayList<PVector> pointsFlattened = new ArrayList<PVector>();

void createPath(int nPoints) {
  for (int i = 0; i < nPoints; i++) {
    float n = (float) i / (float) nPoints;
    float x = sin(n * TAU * 2) * o;
    float y = cos(n * TAU) * o;
    float z = sin(n * TAU) * o;
    PVector p = new PVector(x, y, z);
    path.add(p);
  }
}

void settings() {
  size(612, 792, P3D);
  pixelDensity(displayDensity());
}

void setup() {
  createPath(nPoints);
  noLoop();

  // Create figure
  pushMatrix();
  translate(width / 2.0, height / 2.0, -2100);

  for (int i = 0; i < nRotations / 2; i++) {
    float n = (float) i / (float) nRotations;
    pushMatrix();
    rotateY(n * TAU);

    for (PVector p : path) {
      pushMatrix();
      translate(p.x, p.y, p.z);
      rotateY(-n * TAU);

      // Modulate path
      float d = map(p.y, -o, o, -40, 40); 
      float amp = 12 * sin(n * TAU * 4);
      translate(0, d * sin((p.y / o * amp) * TAU * nRotations), 0);
      translate(d * cos((p.y / o * amp) * TAU * nRotations), 0, 0);

      // Flatten: Convert 3D path points to 2D points
      float x = screenX(0, 0, 0);
      float y = screenY(0, 0, 0);
      float z = screenZ(0, 0, 0);
      pointsFlattened.add(new PVector(x, y, z));
      popMatrix();
    }
    popMatrix();
  }
  popMatrix();
}

void draw() {
  // Display figure on screen
  stroke(0, 128);
  noFill();
  beginShape();
  for (PVector p : pointsFlattened) {
    vertex(p.x, p.y);
  }
  endShape(CLOSE);

  // Generate the PDF
  if (doGeneratePDF) {
    PGraphics pdf = createGraphics(width, height, PDF, "oscillatorsIn3D20171222.pdf");
    pdf.beginDraw();
    pdf.scale(1.0 / displayDensity(), 1.0 / displayDensity()); 
    pdf.beginShape();
    pdf.noFill();
    for (PVector p : pointsFlattened) {
      pdf.vertex(p.x, p.y);
    }
    pdf.endShape(CLOSE);
    pdf.dispose();
    pdf.endDraw();
  }
}