the trick is to use a lib called robot

see

http://www.openprocessing.org/sketch/25255

That's funny  :P  I'm actually using the Robot library (I think) because of advice I got from you in a thread a few weeks ago (am I actually using Robot??).  I apparently am not doing it right though.  I can make the mouse move from one side of the screen to the other when hitting it, but I can't figure out how to translate that into position...  The robot (actual physical robot) I am controlling takes one value for rotation which is scaled from -1 to +1 in the x axis (like the text displayed in the previous program), in the same way as the right(?) gimbal on a game-pad.  I don't know if this helps...

1. //Basic test of Robot library (for moving the mouse)
   
   import processing.core.*;    //add this line ALWAYS to compile Processing
   import java.awt.Robot;
   
   public class MouseInput extends PApplet {                            //always need this line
       public static void main(String args[]) {                         //and this line
           PApplet.main(new String[] { "--present", "MouseInput" });    //and this line (has to match the class name)
       }                                                                //...this one too
      
       //basically just regular processing code from here on
       Robot robot;
       float rmx, rmy;
   
       public void setup() {                  //all "voids" muse be changed to "public voids"
           size(displayWidth,displayHeight);  //NEED to have this line for game-like GUI
           noCursor();
           try{ robot = new Robot(); }
           catch(Throwable e){}
       }
   
       public void draw() {
           background(204);
      
           robot.mouseMove(frame.getX()+this.getX()+round(width/2), frame.getY()+this.getY()+round(height/2));
           rmx += mouseX-width/2;
           rmy += mouseY-height/2;
           rmx = rmx>width?rmx-width:rmx;
           rmx = rmx<0?width+rmx:rmx;
           rmy = rmy>height?rmy-height:rmy;
           rmy = rmy<0?height+rmy:rmy;
           rect(rmx,rmy, 7,7);
       }
   }
   

It's commented so a friend of mine could learn how to do this in Eclipse... not trying to insult your intelligence  :P  I think the speed value would be calculated by using the current mouse position and the previous mouse position, but I don't know how this would work when hitting the boundaries and moving to the other side of the screen...  That's why I have the poorly done example in my first post.

you should be able to see how this works from the code of the example in openprocessing.org

There are also other examples there if you search first person etc.

In the following I move the mouse to the center of the window, then each frame calculate how far it has moved from that point adding the difference to an accumulating variable and then move it back to the center. It is quite a basic example with comments.
http://www.openprocessing.org/sketch/20675

Yeah that's the program I based mine off of (I just modified it).  Thanks for that, btw!  Maybe I'll just have to settle with the original program.  By the way Chrisir, I keep getting an error with your program involving opengl...  that's why I haven't learned much from it...

Oh, an error!

I suppose I wrote it under 1.51 or earlier where old OPENGL stuff was still in place. It won't work with 2.0 I guess.

It never worked in the browser, it is very annoying.

in my code (which is based on rbauers of course)

these are the lines:

1. void draw () {
2. 
   
3.  
4. 
   
5.   fill(101);
6. 
   
7.   background(0);
8. 
   
9.  
10. 
    
11.   plane();  // Floor
12. 
    
13.   walls () ;
14. 
    
15.   buildings() ;
16. 
    
17.  
18. 
    
19.   // very important that this is last in draw()
20. 
    
21.   CheckVirtualMouse ();
22. 
    
23.   CheckCameraMouse ();
24. 
    
25. }
26. 
    
27.  
28. 
    
29. // ===========================================================================================
30. 
    
31.  
32. 
    
33. void CheckCameraMouse () {
34. 
    
35.   // Mouse
36. 
    
37.   // note: Makes use of the values of Robot-Mouse.
38. 
    
39.   float Radius = 450.0;  // Anfangsradius des Kreises
40. 
    
41.  
42. 
    
43.   // command map: See Help.
44. 
    
45.   angle = map(rmx,width,0,0,359); // left right
46. 
    
47.  
48. 
    
49.   // look at
50. 
    
51.   xlookat = Radius*sin(radians(angle)) + xpos;
52. 
    
53.   ylookat = map(rmy,-300,floorLevel-120,-270,height); // look up / down
54. 
    
55.   zlookat = Radius*cos(radians(angle)) + zpos;
56. 
    
57.  
58. 
    
59.   camera (xpos,ypos,zpos,
60. 
    
61.   xlookat, ylookat, zlookat,
62. 
    
63.   0.0, 1.0, 0.0
64. 
    
65.     );
66. 
    
67. }
68. 
    
69.  
70. 
    
71. // -------------------------------------------------------------------------------------------
72. 
    
73.  
74. 
    
75. void CheckVirtualMouse () {
76. 
    
77.  
78. 
    
79.   // Code by rbrauer.
80. 
    
81.   // it won't work in the applet, ie online.
82. 
    
83.   // Copy the source code and try it from the PDE.
84. 
    
85.  
86. 
    
87.   //line moves mouse pos to center of canvas
88. 
    
89.   //frame.getX() is the horizontal pos of the window top left (or so)
90. 
    
91.   //this.getX (or just getX()) gets offset from window frame to canvas
92. 
    
93.   //required because robot's coords are global not relative to canvas
94. 
    
95.   robot.mouseMove(
96. 
    
97.   frame.getX()+this.getX()+round(width/2),
98. 
    
99.   frame.getY()+this.getY()+round(height/2));
100. 
     
101.  
102. 
     
103.   //mouse pos is locked in center of canvas
104. 
     
105.   //above lines subtract the centering, get whatever offset from
106. 
     
107.   //center user creates by moving mouse before robot resets it, then
108. 
     
109.   //continously adds that to our new mouse pos variables
110. 
     
111.   rmx += mouseX-width/2;
112. 
     
113.   rmy += mouseY-height/2;
114. 
     
115.  
116. 
     
117.   //these lines are just shortened conditionals to handle
118. 
     
119.   //wrapping of our mouse pos variables when they go outside canvas
120. 
     
121.   //first one:
122. 
     
123.   //if rmx>width? set rmx to rmx-width else : set rmx to rmx
124. 
     
125.   rmx = rmx>width?rmx-width:rmx;
126. 
     
127.   rmx = rmx<0?width+rmx:rmx;
128. 
     
129.   // check ceiling
130. 
     
131.   if (rmy<-300) {
132. 
     
133.     rmy= -300;
134. 
     
135.   }
136. 
     
137.   // check floor
138. 
     
139.   if (rmy>floorLevel-20) {
140. 
     
141.     rmy= floorLevel-20;
142. 
     
143.   }
144. 
     
145. } // CheckVirtualMouse
146. 
     
147.  
148. // -----------------------------------------------------------

what is interesting maybe is that
I use sin and cos in CheckCameraMouse
to get the camera lookAt position.

Maybe that is the leap you need to make?