This example is for Processing 3+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.

**Follow 1** based on code from Keith Peters.

A line segment is pushed and pulled by the cursor.

float x = 100; float y = 100; float angle1 = 0.0; float segLength = 50; void setup() { size(640, 360); strokeWeight(20.0); stroke(255, 100); } void draw() { background(0); float dx = mouseX - x; float dy = mouseY - y; angle1 = atan2(dy, dx); x = mouseX - (cos(angle1) * segLength); y = mouseY - (sin(angle1) * segLength); segment(x, y, angle1); ellipse(x, y, 20, 20); } void segment(float x, float y, float a) { pushMatrix(); translate(x, y); rotate(a); line(0, 0, segLength, 0); popMatrix(); }