The code below provides an example of a simple recursive function that displays a PShape in a pattern. In this example, the PShape is created within the recursive function. A more modular approach is to create a recursive function that takes the PShape as an input parameter, as the repeat structure can be applied to any PShape to create a similar pattern.
//Recursion and PShapes
//
void setup(){
size( 600, 600);
colorMode(HSB, 360, 100, 100);
//drawCircle( width/2, height/2, 500 ); //call shiffman's recursive function
//PShape myShape1 = createPShape1( 200); //test creating 1 shape
//shape( myShape1, 200, 200); //render test shape on canvas
recursiveMotif( 5, 200); //call custom recursive function
}
//create a PShape based on size input parameter
//return a variable that points to the new PShape object
PShape createPShape1( float size){
PShape s = createShape(RECT,0,0,size, size);
return s;
}
//recursive function, takes count and size as input params
//count controls number of repeats, size used as input to createPShape
void recursiveMotif( int count, float size ){
if( count < 1){
return; //terminate
}
//task: make a shape, render the shape
PShape myShape1 = createPShape1( size); //call custom shape function
shape( myShape1, 0,0); //render the shape to canvas
recursiveMotif( count-1, size * 0.8); //changes in input paramter values control behaviour of recursive call:
}
//Shiffman's recursive circles: Example 8.3
//https://natureofcode.com/book/chapter-8-fractals/
void drawCircle( float x, float y, float diameter ){
if( diameter < 25){ //termination condition
return;
}
fill( 270, 100, 100);
//noFill();
ellipse( x, y, diameter, diameter); //task
drawCircle( x + diameter/2, y, diameter/2 ); //recursive call
drawCircle( x - diameter/2, y, diameter/2 ); //recursive call
drawCircle( x, y + diameter/2, diameter/2 ); //recursive call
drawCircle( x, y - diameter/2, diameter/2 ); //recursive call
ellipse( x, y, diameter, diameter); //task
}
