2. 
   
3. final static int NORTH = 1;
4. final static int EAST = 2;
5. final static int SOUTH = 4;
6. final static int WEST = 8;
7. int result;
8. float x,y;
9. float angle;
10. boolean pressed = false;
11. boolean locked = false;
12. 
    
13. 
    
14. void setup() {
15.   size(900,900);
16.   frameRate(60);  
17.   result = 0;
18.   x = width/2;
19.   y = height/2;
20.   smooth ();
21.    rectMode(CENTER);
22.   }
23.   
24. void draw() {
25.   background(255,0,0);
26.   noStroke();
27.   switch(result) {
28.     case NORTH: y=y-2; break;
29.     case EAST: x=x+2; break;
30.     case SOUTH: y=y+2; break;
31.     case WEST: x=x-2; break;
32.     case NORTH|EAST: y=y-2; x=x+2; break;
33.     case NORTH|WEST: y=y-2; x=x-2; break;
34.     case SOUTH|EAST: y=y+2; x=x+2; break;
35.     case SOUTH|WEST: y=y+2; x=x-2; break;
36.   }
37.   fill(255);
38.   pushMatrix();
39.   translate(x,y);
40.   rotate(angle);
41.   rect(0,0,50,50);
42.   popMatrix();
43.   }
44. 
    
45. void mouseReleased(){
46.   stroke(#007700);
47.   strokeWeight(5);
48.   strokeCap(ROUND);
49.   fill(#009900);
50.   line(x,y,mouseX,mouseY);
51. }
52.    
53. void mouseMoved(){
54.   
55.   angle = atan2(mouseY - y, mouseX - x);
56. }
57.  
58. void keyPressed(){
59.        
60.   switch(key) {
61.     case('w'):case('W'):result |=NORTH;break;
62.     case('d'):case('D'):result |=EAST;break;
63.     case('s'):case('S'):result |=SOUTH;break;
64.     case('a'):case('A'):result |=WEST;break;
65.   }
66. }
67.  
68. void keyReleased(){  
69.   switch(key) {
70.     case('w'):case('W'):result ^=NORTH;break;
71.     case('d'):case('D'):result ^=EAST;break;
72.     case('s'):case('S'):result ^=SOUTH;break;
73.     case('a'):case('A'):result ^=WEST;break;
74.   }
75.   }

So now I want to spawn Zombies, who walk to my character
I did this with a bunch of if loops.

2. float x=400.0;
3. float y=300.0;
4. float a=0.0;
5. float b=0.0;
6. 
   
7. 
   
8. void setup(){
9.   size(800,600);
10.   smooth();
11. }
12. 
    
13. 
    
14. void draw(){
15.   float abstandX=mouseX-x;
16.   float abstandY=mouseY-y;
17.   
18.   fill(100);
19.   ellipse(x,y,50,50);
20.   x=x+a;
21.   y=y+b;
22.   if(abstandX>0 && abstandY>0)                           //unten rechts
23.     {
24.     if(abstandX>abstandY){a=1; b=abstandY/abstandX;}
25.     if(abstandX<abstandY){b=1; a=abstandX/abstandY;}
26.     }
27.   
28.   if(abstandX>0 && abstandY<0)                           //oben rechts
29.     {
30.     if(abstandX>-abstandY){a=1; b=abstandY/abstandX;}
31.     if(abstandX<-abstandY){b=-1; a=abstandX/-abstandY;}
32.     }
33.   
34.   if(abstandX<0 && abstandY>0)                           //unten links
35.     {
36.     if(-abstandX>abstandY){a=-1; b=abstandY/-abstandX;}
37.     if(-abstandX<abstandY){b=1; a=-abstandX/-abstandY;}
38.     }
39.   
40.   if(abstandX<0 && abstandY<0)                           //oben links
41.     {
42.     if(-abstandX>-abstandY){a=-1; b=abstandY/-abstandX;}
43.     if(-abstandX<-abstandY){b=-1; a=-abstandX/abstandY;}
44.     }
45. 
    
46. } 

Now they follow the character, but I don't know, how I could let them spawn from the border.
Also they should spawn to a random time, and I don't know how to integrate time in my game.
So first the zombie(the ellipse) should follow the character and not the mouse anymore.
And if you could help me with this spawning thing, I'd be thankful.

I have a problem and after lots of hours testing and trying I have no idea what else I can do.
So I'm begging you to help me. I also have to say, I'm very newbie with processing,
we did a bit in school :S

So I want to do a 2D Shooter (in bird's eye view), and the character should be movable with "wasd".
This one is not the problem, but i also want the character rotating/look in direction of the cursor.
Both things I can do easily, but I don't get how I achieve to combine those two things.

1. //Moving an object
2. 
   
3. final static int NORTH = 1;
4. final static int EAST = 2;
5. final static int SOUTH = 4;
6. final static int WEST = 8;
7. int result;
8. float x,y;
9.  
10. void setup() {
11.   size(512,400);
12.   frameRate(60);  
13.   result = 0;
14.   x = width/2;
15.   y = height/2;
16. }
17.  
18. void draw() {
19.   background(0);
20.   switch(result) {
21.     case NORTH: y--; break;
22.     case EAST: x++; break;
23.     case SOUTH: y++; break;
24.     case WEST: x--; break;
25.     case NORTH|EAST: y--; x++; break;
26.     case NORTH|WEST: y--; x--; break;
27.     case SOUTH|EAST: y++; x++; break;
28.     case SOUTH|WEST: y++; x--; break;
29.   }
30.   fill(255);
31.   rect(x,y,50,50);
32. }
33.  
34. void keyPressed(){
35.   switch(key) {
36.     case('w'):case('W'):result |=NORTH;break;
37.     case('d'):case('D'):result |=EAST;break;
38.     case('s'):case('S'):result |=SOUTH;break;
39.     case('a'):case('A'):result |=WEST;break;
40.   }
41. }
42.  
43. void keyReleased(){  
44.   switch(key) {
45.     case('w'):case('W'):result ^=NORTH;break;
46.     case('d'):case('D'):result ^=EAST;break;
47.     case('s'):case('S'):result ^=SOUTH;break;
48.     case('a'):case('A'):result ^=WEST;break;
49.   }
50. }

2. //Rotating an object
3. 
   
5. float angle, oldAngle = 0;
6. 
   
7. void setup(){
8.   size(1200,900);
9.   smooth();
10.   background (30,50,110); 
11. }
12. 
    
13. void draw(){
14.       angle = atan2(mouseY-height/2,mouseX-width/2)+oldAngle ;
15.       translate(width/2,height/2);
16.       rotate(angle);
17.       rectMode(CENTER);
18.       background (0);
19.       rect (0,0,50,50);
20.                 
21. }