import javax.media.opengl.*;
import processing.opengl.*;
import jsyphon.*; // Syphon

JSyphonServer mySyphon;
PGraphicsOpenGL pgl;
GL gl;
int[] texID;

void setup() {
  size(640, 480, OPENGL);
  pgl = (PGraphicsOpenGL) g;
  gl = pgl.gl;
  initSyphon(gl,"processing");

  strokeWeight(0.5);
  stroke(255, 50);
  background(0);

}

void draw() {
  line(width/2, height/2, random(0, width), random(0, height));
  renderTexture(pgl.gl);
}

void initSyphon(GL gl, String theName) {
    if(mySyphon!=null) {
      mySyphon.stop();
    }
    mySyphon = new JSyphonServer();
    mySyphon.test();
    mySyphon.initWithName(theName);

    // copy to texture, to send to Syphon.
    texID = new int[1];
    gl.glGenTextures(1, texID, 0);
    gl.glBindTexture(gl.GL_TEXTURE_RECTANGLE_EXT, texID[0]);
    gl.glTexImage2D(gl.GL_TEXTURE_RECTANGLE_EXT, 0, gl.GL_RGBA8, width, height, 0, gl.GL_RGBA, gl.GL_UNSIGNED_BYTE, null);
} 

void renderTexture(GL gl) {
  gl.glBindTexture(gl.GL_TEXTURE_RECTANGLE_EXT, texID[0]);
  gl.glCopyTexSubImage2D(gl.GL_TEXTURE_RECTANGLE_EXT, 0, 0, 0, 0, 0, width, height);
  mySyphon.publishFrameTexture(texID[0], gl.GL_TEXTURE_RECTANGLE_EXT, 0, 0, width, height, width, height, false);
}

public void stop() {
  dispose();
}

void dispose() {
  println("\n\nabout to stop sketch ...");
  println("deleting textures");
  gl.glDeleteTextures(1, texID, 0);
  if(mySyphon!=null) {
    println("stopping the syphon server");
    mySyphon.stop();
  }
  println("sketch stopped, done.");
}