I need to save a frame in PDF from a animation, so I used the processing.PDF library. I writed my code based on the example of the reference of the library ( http://processing.org/reference/libraries/pdf/). A part of the code:

1. import processing.pdf.*;
2. 
   
3. void setup(){
4.   
5. size(1600,900);
6. background(255);
7. noFill();
8. smooth();
9. record = false;
10. px = width/2;
11. py = height/2;
12. logo = loadImage("logo.png");
13. image(logo,width/2 - 250,height/2 - 50);
14. 
    
15. }
16. 
    
17. void draw(){
18.   
19.    if (record) {
20.     beginRaw(PDF, "output.pdf");
21.   }
22.   if (record) {
23.     endRaw();
24.     record = false;
25.   }
26. 
    
27. 
    
28. void keyPressed(){
29.  
30.   if (key == 'r' || key == 'R') {
31.     record = true;
32.   }
33.   
34. }

When I press the key 'r' to save the PDF the program still run, but no file is saved. This message shows in the display:

beginRaw() is not available with this renderer

endRaw() is not available with this renderer

I've already used this sames functions to save PDFs files of animations, but using the P3D renderer. I tried to use in this code and the previous error was not displayed, but the file saved has no graphics saved, it's just a white PDF of 0kb. Besides, using P3D modifies the graphics that I'm trying to save, that are just a bunch of lines with a large stroke width.

I really need to save these PDFs for an illustration. Can someone help me? Thanks.