a port of the Processing Visualization Language

PolarToCartesian

by Daniel Shiffman. Convert a polar coordinate (r,theta) to cartesian (x,y): x = rcos(theta) y = rsin(theta)

Original Processing.org Example: PolarToCartesian

// All Examples Written by Casey Reas and Ben Fry

// unless otherwise stated.

float r;



// Angle and angular velocity, accleration

float theta;

float theta_vel;

float theta_acc;



void setup() {

  size(200,200);

  frameRate(30);

  smooth();

  

  // Initialize all values

  r = 50.0f;

  theta = 0.0f;

  theta_vel = 0.0f;

  theta_acc = 0.0001f;

}



void draw() {

  background(0);

  // Translate the origin point to the center of the screen

  translate(width/2,height/2);

  

  // Convert polar to cartesian

  float x = r * cos(theta);

  float y = r * sin(theta);

  

  // Draw the ellipse at the cartesian coordinate

  ellipseMode(CENTER);

  noStroke();

  fill(200);

  ellipse(x,y,16,16);

  

  // Apply acceleration and velocity to angle (r remains static in this example)

  theta_vel += theta_acc;

  theta += theta_vel;



}
Fork me on GitHub