See the reference. You can use createFont() on runtime. Or you can create the font using the aptly named Tool from the menu and then use loadFont() on the resulting file. Both options can handle different fonts. So I suggest you point it towards a turkish font and then try to draw some text with special characters on the screen to see if it works ok.

Thanks, I wasn't aware of the createFont() method, sorry.

The following code works fine for me...

1. PFont wordFont100;
2.  
3. void setup () {
4.   size (1000, 500, P3D);
5.   wordFont100 = createFont ("FrutigerLTCom-LightCn", 100);
6.   textFont (wordFont100, 100);
7.   smooth();
8. }
9.  
10. void draw () {
11.   background (0);
12.   text ("ağaç ateş açılmak", 100, 100);
13. }