Instruction
| Basketball |
It's the main character on the stage. It moves, it bounces,
it rotates, it collides with objects, and it reacts to
the gravity. You can drag the ball and throw it using
the mouse as hard as you can. Try throwing it into the
basket. |
| Basket |
You can adjust the height of the basket along the left
side of the stage. |
| Magnet Blocks |
There are two magnet blocks on
the left side of the stage. You can drag and place them
anywhere on the stage. These magnet blocks are static
and they don't move. Try to throw a ball across a magnet,
and you will see the ball sticks to it. It only happens
on top of the magnets. To make the shooting more challenging,
place some magnet blocks near the basket. |
| Gravity |
The gravity will pull the ball but not the magnet blocks.
You can change the gravity in the range from 0 to 3. Where
1 means 100% of the earth's gravity. |
Basic Physics
To make the ball bounces and reacts realisticly, we need
to have some basic knowledge of physics to program this interactive
dynamic system with ActionScript. I used the Newton's laws
for physics. In order to have the ball fall, we need to have
the gravity force to pull the ball downward. The force needed
to lift the ball up is depends on how hard the user throw
it. When you apply a force to the ball the velocity will be
created upon the ball, it will move upward and decelerate
by the gravity, and when the force is finally cancelled out
completely by the gravity force, the ball started to accelerate
down back to the earth. So, that's all we need to have the
ball move in the y-axis. The ball doesn't
move by itself in the x-axis. You can throw it in the x
direction. For this simple project, there is no air resistence
in the air. So, the ball will not slow down before it hits
the ground. We need to have a force to slow down and stop the ball
when it reaches the ground. This force is called the friction.
What friction does is simply deccelerate the ball in the opposite
direction of where the ball moves in the x-axis. When the
ball's x velocity is zero, it is completely at halt.
Now we have all the forces to move the ball. The next thing
we need to consider is the collision detections. There are
not much collision to detect in this project, the only collisions
occur are between the ball and walls, and the ball and the
blocks.
Original Idea
My original idea for this project is that user can draw on
the stage and then by putting the ball on the lines that you
drew, the ball will bounce or roll along the lines according
to how much force you applied to it. However, I give up with
this idea.
|
