Does anyone know how i set Pshader as my background as im using the nebula sample as my background image and i want my polygon shapes to appear on top of the nebula, i can get either the nebula effect to appear inside of my polygon shapes or i just get the nebula but no polygon shapes ill show u the code and hopfully some one can help this newbie out.

kind regards

carl reeves

 

/**
 * PolygonPShapeOOP.
 *
 * Wrapping a PShape inside a custom class
 * and demonstrating how we can have a multiple objects each
 * using the same PShape.
 */
PShader nebula;

// A list of objects
ArrayList<Polygon> polygons;

void setup() {
  size(640, 640, P2D);
  smooth();
 
  nebula = loadShader("nebula.glsl");
  nebula.set("resolution", float(width), float(height));
 
  // Make a PShape
  PShape star = createShape();
  star.fill(0,127);
  star.stroke(0);
  star.vertex(0, -50);
  star.vertex(14, -20);
  star.vertex(47, -15);
  star.vertex(23, 7);
  star.vertex(29, 40);
  star.vertex(0, 25);
  star.vertex(-29, 40);
  star.vertex(-23, 7);
  star.vertex(-47, -15);
  star.vertex(-14, -20);
  star.end(CLOSE);
 
  // Make an ArrayList
  polygons = new ArrayList<Polygon>();
 
  // Add a bunch of objects to the ArrayList
  // Pass in reference to the PShape
  // We coud make polygons with different PShapes
  for (int i = 0; i < 25; i++) {
    polygons.add(new Polygon(star));
   
  }
}

void draw() {
  background(255);
  nebula.set("time", millis() / 500.0); 
  shader(nebula);
  // This kind of raymarching effects are entirely implemented in the
  // fragment shader, they only need a quad covering the entire view
  // area so every pixel is pushed through the shader.
  //rect(0, 0, width, height);

  // Display and move them all
  for (Polygon poly : polygons) {
    poly.display();
    poly.move();
  }
}