This is a duplicate of of a post you made 8 hours earlier in General Discussion. Please do not duplicate posts in different parts of the forum, since the original had no response I have deleted it. Also this section is more appropriate for your question.

As to your question re velocity one solution would be to update the position inside the draw method. So lets assume that we have something moving at speed s (distance travelledin one frame update) at an angle a (in radians) then the change in the x and y position will be given by

deltaX = v * cos(a);
deltaY = v * sin(a);

The following sketch is a very simple example of what I mean.

1. float x, y, v, a;
2. float deltaX, deltaY;
3. 
   
4. void setup() {
5.   size(600, 480);
6.   x = 10;
7.   y = 10;
8.   v = 1;
9.   a = radians(30);
10.   fill(255);
11.   noStroke();
12. }
13. 
    
14. void draw() {
15.   background(0);
16.   deltaX = v * cos(a);
17.   deltaY = v * sin(a);
18.   x += deltaX;
19.   y += deltaY;
20.   ellipse(x, y, 10, 10);
21. }