// draw polygons using lines

void setup() { // all sketch setup goes here
   size(400, 400);
   smooth();
   background(255);
   } // setup() 

void draw() {
     
     
     } // draw()

void mousePressed() {
   drawPolygon(mouseX, mouseY, random(20, 80), int(random(3, 12)));
   } // mousePressed()

void drawPolygon(float cx, float cy, float sz, int nSides) {
   // draw a hexagon centered at cx, cy
   float x1, y1, x2, y2;
   float radius = sz/2;
   float theta = 0.0;
   float delta = 360.0/nSides;

 point(cx, cy);
   // ellipse(cx, cy, sz, sz);

 // compute x1, y1
   x1 = cx + radius;
   y1 = cy;
   for (int i = 0; i < nSides; i++) {
   theta = theta + delta;
   x2 = cx + radius * cos(radians(theta));
   y2 = cy - radius * sin(radians(theta));
   line(x1, y1, x2, y2);
   
   // copy x2, y2 into x1, y1
   x1 = x2;
   y1 = y2; 
   }
   } // drawPolygon