Develop a Sprite and Platform Game - Unity 3 Game Development - page 25

In our code, we use the Input.GetButton("Horizontal") funcion. GetButton means
we are checking if the Horizontal buton is being held down. The Horizontal is the
name of the irst input buton, as we can see in the preceding screenshot. We can also use
Input.GetKey("left") to control our character. It will have the same result with Input.
GetButton , but the difference is GetKey will only detect the specific key in our code. It
isn't lexible for the user to adjust the key coniguraion during the game play. The Negative
Button and Positive Button here will send the negaive and posiive value, which in most
cases is used for controlling direcion such as let, right, up, and down. There is a Dead
parameter, which will set any number that is lower than this parameter to 0 , which is very
useful when we use a joysick. Also, seing the Type to key/mouse button and enabling the
Snap parameter will reset axis values to zero after it receives opposite inputs.
Jumping and physics
Now, we are making our character jump by using Physics.Raycast in Unity. We can also
use the OnCollisionEnter , OnCollisionExit , or OnCollisionStay funcions to
check the collision detecion between our character and the loor, but in this case we will use
Raycast because it's more flexible to adjust.
However, because the Raycast is only a line with no thickness, there is a chance that if
we have a very thin plaform, the Raycast can miss it. And it will cause the problem that
we might not be able to jump. So, we should make sure that the plaform should have the
thickness of least 0.1 units.
Engage Thrusters
Coninuing from the last step, let's get on with it as follows:
1. Let's open our CharacterController_2D.js file and add this code to it; first
our parameters:
private var b_isJumping : boolean;
private var f_height : float;
private var f_lastY : float;
public var jumpSprite : JumpSpriteManager;
public var layerMask : LayerMask; //to check for the raycast
2. Then, we go to the public function Start () funcion and add the following
code inside this funcion:
//Get mesh from the character MeshFilter
mesh = GetComponent(MeshFilter).sharedMesh;
//Get hight from the top of our character to the bottom of our
box collider
f_height = mesh.bounds.size.y* transform.localScale.y;