I have found the following way to enable texture repeats.

Is directly accessing g (line 7) an acceptable way of doing this (the website used to discourage this) or is there a function (in 2.0a6) to control texture repeating and clamping?

1. PImage img;
2. 
   
3. void setup(){
4.   size(400,400, OPENGL);
5.   img = loadImage("picture.jpg");
6.   textureMode(NORMAL);
7.   ((PGraphicsOpenGL)g).textureWrap = Texture.REPEAT;
8. }
9. 
   
10. void draw(){
11.   background(0);
12.    beginShape(QUADS);
13.    texture(img);
14.    vertex(0,0,0,0);
15.    vertex(0,400,0,2.5);
16.    vertex(400,400,2.5,2.5);
17.    vertex(400,0,2.5,0);
18.    endShape();
19. }