Original Processing.org Example: Pentigree
// All Examples Written by Casey Reas and Ben Fry // unless otherwise stated. /** * Pentigree L-System * by Geraldine Sarmiento (Interactive Telecommunications Program, NYU). * This code was based on Patrick Dwyer's L-System class. */ PentigreeLSystem ps; void setup() { size(200, 200); frameRate(24); smooth(); ps = new PentigreeLSystem(); ps.simulate(3); } void draw() { background(0); ps.render(); } class LSystem { int steps = 0; String axiom; String rule; String production; float startLength; float drawLength; float theta; int generations; LSystem() { axiom = "F"; rule = "F+F-F"; startLength = 90.0f; theta = radians(120.0); reset(); } void reset() { production = axiom; drawLength = startLength; generations = 0; } int getAge() { return generations; } void render() { translate(width/2, height/2); steps += 5; if (steps > production.length()) { steps = production.length(); } for (int i = 0; i < steps; i++) { char step = production.charAt(i); if (step == 'F') { rect(0, 0, -drawLength, -drawLength); noFill(); translate(0, -drawLength); } else if (step == '+') { rotate(theta); } else if (step == '-') { rotate(-theta); } else if (step == '[') { pushMatrix(); } else if (step == ']') { popMatrix(); } } } void simulate(int gen) { while (getAge() < gen) { production = iterate(production, rule); } } String iterate(String prod_, String rule_) { drawLength = drawLength * 0.6; generations++; String newProduction = prod_; newProduction = newProduction.replaceAll("F", rule_); return newProduction; } } class PentigreeLSystem extends LSystem { int steps = 0; float somestep = 0.1; float xoff = 0.01; PentigreeLSystem() { axiom = "F-F-F-F-F"; rule = "F-F++F+F-F-F"; startLength = 40.0; theta = radians(72); reset(); } void useRule(String r_) { rule = r_; } void useAxiom(String a_) { axiom = a_; } void useLength(float l_) { startLength = l_; } void useTheta(float t_) { theta = radians(t_); } void reset() { production = axiom; drawLength = startLength; generations = 0; } int getAge() { return generations; } void render() { translate(width/4, height/2); steps += 3; if (steps > production.length()) { steps = production.length(); } for (int i = 0; i < steps; i++) { char step = production.charAt(i); if (step == 'F') { noFill(); stroke(255); line(0, 0, 0, -drawLength); translate(0, -drawLength); } else if (step == '+') { rotate(theta); } else if (step == '-') { rotate(-theta); } else if (step == '[') { pushMatrix(); } else if (step == ']') { popMatrix(); } } } }