I am attempting to design a function that will draw a reuleaux triangle.

My approach is to translate to the centre of the Processing window and then use the Beziervertex functions to draw each arc, but before each conscutive arc, implement a rotation translation, such that the same code for the first arc is simply repeated for the 2 other arcs.

This strangely failed as I had to manually vary the controls for the curves in the Bezier functions, seemingly due to the translation not working as I expected.

Any help would be appreciated (code below)....... (see lines 47, 50, 53)

int w = 400; //window width
int h = 200; //window height
int l = h/2; //equilateral triangle side size
float p = 24;

void setup() {
  background(255);
  size(w,h);
  noFill();
 
  //translate to centre
 
  translate(w/2,h/2);
 
  // calculate trigonometric variables
 
  float r = ( (l/2) / (cos(PI/6) ) );
  float p = r * sin(PI/6);
  float x = p / tan(PI/6);

  // draw background outlines
 
  ellipse(0,0,2*r,2*r);
  line(0,0,0,-h/2);  
  rotate(2*(PI/3));
  line(0,0,0,-h/2);  
  rotate(2*(PI/3));
  line(0,0,0,-h/2);  
  rotate(2*(PI/3));
  strokeWeight(3);
  // left lower point
  point(x, p);
  // right lower point
  point(-x, p);
  // top point
  point(0, -r);

  // reuleaux triangle shape
 
  noStroke();
  smooth();
  fill(175,200);
  beginShape();
  // lower left vertex
  vertex(x, p);
  // bottom arc
  bezierVertex(x, p, 0, h/10*3, -x, p);
  // left arc
  rotate(2*(PI/3));
  bezierVertex(-x, p, -h/10*2.5, -h/10*1, 0, -r);
  // right arc
  rotate(4*(PI/3));
  bezierVertex(0, -r, h/10*2.2, -h/10*2, x, p);
  endShape();
}