have backgound at the beginning of draw
then the circle stuff, then triangles
no background in drawTriangle please

but i dont want void drawCircles to be in the void Draw. do you know how to do it then?

show your code

you could paint your circles into an virtual image and then with background display the image within draw()
see http://www.processing.org/reference/PGraphics.html


Remark
to draw the circles only once and then draw the triangles without usage of background is virtually impossible since you have to delete the triangle without destroying the circles under it

yes, you need to define a class circle,
define them via random in setup(), store them all in an arrayList or array and then just
put them out in draw, always in there stored position.

Then check whether they collide with pacman

like this...

1. ArrayList<Ball> balls;
2. int xPos = 10;
3. int yPos = 0;
4. int rectWidth = 30;
5. int rectHeight = 30;
6. int beginPosition = 0;
7. int stopPosition = 150;
8. int mouseVar;
9. float rCol, gCol, bCol;
10. void setup() {
11.   size(400, 800);
12.   frameRate(10);
13.   smooth();
14.   noStroke();
15.   balls = new ArrayList();
16.   for (int i=0; i<random (12,23); i++)
17.     balls.add(new Ball( random(0, width), random(0, height),
18.     rectWidth, rectHeight,
19.     beginPosition, stopPosition,
20.     random(0, 255), random(0, 255), random(0, 255)));
21.   //
22. } // func
23. void draw() {
24.   background(255);
25.   // for-loop
26.   for (int i = balls.size()-1; i >= 0; i--) {
27.     Ball ball = balls.get(i);
28.     // ball.moveThis();
29.     ball.display();
30.   } // for
31.   //  // a new for-loop to delete balls
32.   //  // (it is better to have 2 separate for-loops)
33.   //  for (int i = balls.size()-1; i >= 0; i--) {
34.   //    Ball ball = balls.get(i);
35.   //    if (ball.y+ball.h > height) {
36.   //      balls.remove(i);
37.   //    } // if
38.   //  } // for
39.   println(balls.size());
40. } // func
41. //void mouseReleased() {
42. //  for (int i = 0; i < balls.size(); i++) {
43. //    Ball ball = balls.get(i);
44. //    ball.stopPos+=150;
45. //  } // for
46. //  yPos = mouseVar * 150;
47. //  mouseVar = (mouseVar+1) % 5;
48. //  mouseVar++;
49. //  rCol = random(255);
50. //  gCol = random(255);
51. //  bCol = random(255);
52. //} // func
53. // ==================================================
54. class Ball { 
55.   // pos
56.   float x;
57.   float y;
58.   // size
59.   float w;
60.   float h;
61.   // movement
62.   float beginPos;
63.   float stopPos;
64.   float speed = 5;
65.   // color // or use color
66.   float r, g, b;
67.   Ball(float tempX, float tempY,
68.   float tempW, float tempH,
69.   float tempBegin, float tempStop,
70.   float tempR, float tempG, float tempB) {
71.     x = tempX;
72.     y = tempY;
73.     w = tempW;
74.     h = tempH;
75.     beginPos = tempBegin;
76.     stopPos = tempStop;
77.     r = tempR;
78.     g = tempG;
79.     b = tempB;
80.   }
81.   void moveThis() {
82.     y = y + speed;
83.     if (y > stopPos) {
84.       y = stopPos;
85.     }
86.   }
87.   void display() {
88.     fill(r, g, b);
89.     //rect(x, y, w, h);
90.     ellipse (x, y, w, w);
91.   }
92.   //
93. } // class
94. //

like this...

1. float [] ballFallX = new float [0];
2. float [] ballFallY = new float [0];
3. color [] ballFallColor = new color [0];
4. float ballspeed;
5. //
6. void setup() {
7.   size(700, 700);
8.   ballspeed=5;
9.   println("drag or click mouse");
10. }
11. //
12. void draw() {
13.   background(0);
14.   for  (int i=0; i<ballFallX.length; i++) {
15.     fill (map(ballFallX[i], 0, width, 0, 255), 0, 111);
16.     fill (ballFallColor[i]);
17.     ellipse(ballFallX[i], ballFallY[i], 50, 50);
18.     println ("Here is the X array " +ballFallX[i]);
19.     // ballFallY[i] += ballspeed;
20.     //    if (ballFallY[i]>=height-63) {
21.     //      removeItemFromArray( i );
22.     //    }
23.   }
24. }
25. void mousePressed () {
26.   appendMousePos();
27. }
28. void mouseDragged () {
29.   appendMousePos();
30. }
31. //--------------------------------------------
32. // tools
33. void appendMousePos() {
34.   ballFallX = append(ballFallX, mouseX);
35.   ballFallY = append(ballFallY, mouseY);
36.   ballFallColor = append(ballFallColor, color (random(0, 255), random(0, 255), random(0, 255)));
37. }
38. void removeItemFromArray( int i ) {
39.   //
40.   if (i!=ballFallX.length-1) {
41.     ballFallX[i] = ballFallX[ballFallX.length-1];
42.     ballFallY[i] = ballFallY[ballFallX.length-1];
43.   }
44.   // shorten
45.   ballFallX = (float[]) shorten(ballFallX);
46.   ballFallY = (float[]) shorten(ballFallY);
47. }
48. //