Hi I'm doing simple visualization where I want to plot one molecular geometry over the other where. I want to render first both molecules into some image buffer independently, and than do some image composition to overplay it.

I expected that this code should do the same, but it does not. Looks like that some features does not work in P3D offscreen rendering (like background()  , material definitions, lightning definitions ......  )


Without offscreen rendering

1. void setup()
   {
     smooth();
     size(800, 800, P3D);
     colorMode(RGB, 1);
     ortho(-width/2, width/2, -height/2, height/2, -10, 10);
   }
   
   
   
   void draw()
   {
     background(1.0,1.0,1.0);
     pushMatrix();
     lightSpecular(1.0, 1.0, 1.0 );  // color of specular light
     specular(0.5, 0.5, 0.5);        // color of specular material
     ambientLight(0.5, 0.5, 0.5);            // color of ambient light
     directionalLight(1, 1, 1, -1, -1, -1);  // color and position of directional light
     shininess(50.0);
     sphereDetail(20);
     translate(400, 400, -30);
     rotateX((400-mouseY)*0.01);
     rotateZ(mouseX*0.01); 
     scale(20); 
     specular (0.0, 0.0, 0.0);
     noStroke();
     sphere(10);
     stroke(0.5);
     strokeWeight(4);
     noLights();
     translate(10,10,10);
     sphere(10);
     popMatrix();
   }
   

With offscreen rendering

1. PGraphics PG0,PG1;
   
   
   void setPG(PGraphics PG) {
    g.endDraw();
    g = PG;
    g.beginDraw();
   }
   
   void setup()
   {
    
     smooth();
     size(800, 800, P2D);
     size(800, 800, P2D);
     PG0 = g;
   
     PG1 = createGraphics(width,height, P3D);
     PG1.smooth();
     PG1.noStroke();
     PG1.colorMode(RGB, 1);
     PG1.ortho(-width/2, width/2, -height/2, height/2, -10, 10);
    
   }
   
   
   
   void draw()
   {
    
     setPG(PG1);
     background(1.0,1.0,1.0);
     pushMatrix();
     lightSpecular(1.0, 1.0, 1.0 );  // color of specular light
     specular(0.5, 0.5, 0.5);        // color of specular material
     ambientLight(0.5, 0.5, 0.5);            // color of ambient light
     directionalLight(1, 1, 1, -1, -1, -1);  // color and position of directional light
     shininess(50.0);
     sphereDetail(20);
     translate(400, 400, -30);
     rotateX((400-mouseY)*0.01);
     rotateZ(mouseX*0.01); 
     scale(20); 
     specular (0.0, 0.0, 0.0);
     noStroke();
     sphere(10);
     stroke(0.5);
     strokeWeight(4);
     noLights();
     translate(10,10,10);
     sphere(10);
     popMatrix();
    
     setPG(PG0);
     image(PG1, 0, 0);
    
   }