UNITY | PROJECT | SPACE SHOOTER 2D | 3. Player Bullet and Player Shooting

SPACE SHOOTER 2D

3. Player Bullet and Player Shooting

Bullet Sprites

• Importing “Bullets” sprite

 

Sprite Editor | Slice

 

• by using “Sprite Editor”, slice “Bullets” sprites into 2 sprites
  • when slicing, set the type into “Grid By Cell Size”
  • when slicing, set the Pixel Size as 24×24

 

• Having 2 bullet sprites

 

Sprite Setting

• for the bullet sprite in the inspector
  • deselect “Generate Physics Shape”
  • Filter Mode into “Point(no filter)”
  • Max Size into “1024”

 

Adding prefab in the scene

• Add “Player Bullet” sprite in the scene to configure like adding a script

 

Adding a script to Bullet GameObject

• Adding “PlayerBullet” script to “PlayerBullet” GameObject

 

“PlayerBullet” Script

• set the public variable “speed” for the speed of the bullet
• In “Update()” method
  • get the bullet’s current position by using “transform.position”
  • computing the bullet’s new position = the change of position when we shoot the bullet
    • only need to change the “y” value
  • to smooth the shooting, use “Time.deltaTime”
  • Don’t forget to update the position into “transform.position”
• for the memory usage, destroy the bullets going outside the screen
  • when setting the screen range, only consider “y” value or “height”
  • “Camera.main.ViewPortToWorlPoint()”

 

Setting the speed in the inspector | Public Variable

Shoot a bullet

 

Making a Prefab

• Make the Bullet Prefab by dragging the bullet we configured in the Hierarchy window
  • this is the Bullet we will continuously instantiate

 

Empty GameObject

 

GameObject BulletPosition

GameObject BulletPosition

• Make 2 Empty GameObject to Create “BulletPosition”, where Bullets come out
  • Set the position of  “BulletPosition” on “Player” GameObject

 

Child Object

• Make “BulletPosition” as a ChildObject of “Player”
  • “BulletPosition” belongs to “Player”

 

“Player Control

• Set Public Variables to use those components in the script

 

Public Variable | Reference

 

Player Control

• In “Update()” method
  • Instantiate Bullet Prefab when “SpcaeBar” is pressed
  • set the initial position of a bullet after instantiating

 

Player Shooting | Destroying Bullets

 

UNITY | PROJECT | SPACE SHOOTER 2D | 2. Player Input Movement

SPACE SHOOTER 2D

2. Player Input Movement

Player Control Script

• Creating & Adding “PlayerControl” script

Player Control Script | Update() | Input.GetAxisRaw()

• setting “speed” variable as public to see in the inspector
• In “Update()”
  • set horizontal & vertical input by using Input.GetAxisRaw()
    • with Input.GetAxisRaw(), the values will be -1, 0 or 1
  • with the two inputs, make “direction”
    • by adding “.normalize”, make a unit vector
  • add a customized fuction “Move()” to move “Player”
    • we need this fuction in “Update()” because “Player”‘s position must be changed and detected every frame

 

Player Control script | Move() | Vector2 | Camera.main.ViewportToWorldPoint()

• to limit the Filed where “Player” can move, get the screen size by using “Camera.main.ViewportToWorldPoint()”
  • ViewPort has a range (0, 0) to (1, 1)

 

Player Control script | Move() | transform.position | Mathf.Clamp()

• get the Player’s current position with “transform.position”
  • transform.position of the gameObject this script is attached to
• calculate the new position in “currentPosition” variable
  • with “speed” variable, we can change the speed of “Player”
    • “direction” is the normalized vector2
    • “Time.deltaTime” is very important with this, we smooth the movement

without “Time.deltaTime”, the value(“direction”) is almost (0, 0), (1, 0)……

 

Setting Player’s Speed | Public Variable

 

Player Input Movement

Player Input Movement | without Time.deltatime

• without “Time.deltaTime”, “Player” moves too dynamically