i am trying to make "stars" and i am starting off simple, i made a variable "a", and if its less than 255 it adds 1 to "a", if its greater than 255 it takes away 1. but obviosuly as soon as it takea 1 away it will add 1, again and be stuf at 255. i am not sure how i can workaround this... without an array though.

 

int[] starx = new int[50];
int[] stary = new int[50];
int a = 0;

void setup()//open setup
{
  smooth();
  size(500,500);
  //set x, y values
  for (int i = 0; i <50; i++)
  {
    starx[i] = int(random(500));
    stary[i] = int(random(500));
    }
}//end setup
//
void draw()//open draw
{
  smooth();
  background(0);
 
   //check the alpha value
   if (a < 255)
  {
    a += 1;
  }
  if(a<255) ///<<<<<@@@@@@ if it goes below it will add 1 again
  {
    a -= 1;
  }
  //draws all the circles
  for (int i = 0; i <50; i++)
  {
    fill(255, a);
    ellipse(starx[i],stary[i], 5, 5);
  }
 
}//end draw

so i have to do a project, which is to make a simple galaga/ space invaders clone, i managed to get the thing working using just the main class(1 tab <<<noob =/) but now i would like to break it off into classes and i am having some issues with moving the ship(a triangle), every time the movment key the ship keeps moving in that direction instead of moving in steps.

here is the main class 

2. //SIZE
3. int width = 400;
4. int height = width;
5. 
   
6. //SHIP CENTER COORDINATES + OBEJECT
7. int shipCenterX = 200;
8. int shipCenterY = 380;
9. ship shipA;
10. 
    
11. //INITIALIZE GAME
12. void setup()
13. {
14.   size(width, height);
15.   shipA = new ship(shipCenterX, shipCenterY, width, height);
16. }
17. 
    
18. 
    
19. //DRAW GAME
20. void draw()
21. {
22.   background(0);
23.   shipA.keyPressed();
24.   shipA.drawShip();
25.   
26. }

and here is the ship class 

2. class ship
3. { 
4.   int x, y, w, h;
5.   
6.   ship(int x, int y, int w, int h)
7.   {
8.     this.x = x;
9.     this.y = y;
10.     this.w = w;
11.     this.h = h;
12.   }
13.   
14.   void drawShip()
15.   {
16.     fill(255);
17.     triangle(x - 10, y + 10, x, y, x + 10, y + 10);
18.   }
19.   
20.   //TRIANFGLE MOVEMENT
21.   void keyPressed()
22.   {
23.     if (key == CODED)
24.     {
25.       switch(keyCode)
26.        {
27.         case LEFT:
28.         x -= 3;
29.         if (x < 0)
30.         {
31.          x = width;
32.         } 
33.         break;
34.         //
35.         case RIGHT:
36.         x += 3;
37.         if (x > width)
38.         {
39.           x = 0;
40.         }
41.         break;
42.         //
43.         //case UP:
44.          //shoot = true;
45.          //break;
46.      }
47.     }
48.   }
49. }
50.   
51.   
52.    
53.