Chapter 2 Unity Basic Script

Table of contents

1. Basic knowledge

1. Definition

2. Requirements

3. Compile and run the process

4. Small knowledge points

2. Script life cycle

1. name

2. Small method

3. Initial stage

4. Physical stage

5. Game logic

6. Input events

7. Scene rendering

8. Closing phase

3. Debugging

1. Check whether the method is executed or not

2. Watch the time change

3. Start debugging

4. Animation

1. Record animation

2. Statement

5. Common APIs

1. Component components

2. Transform

3. GameObject

4. Object

5. Time

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• 1. Basic knowledge

  • 1. Definition

    • The instruction code attached to the game object to define the behavior of the game object
    • A script is a class, and when you hang it on an object, you create an object

  • 2. Requirements

    • use namespace
    • Script classes attached to game objects must inherit from the MonoBehaciour class
    • The file name must match the class name
    • Written scripts must be attached to objects to run

  • 3. Compile and run the process

    • Source Code - (CLS) -> Intermediate Language - (Mono Runtime) -> Machine Code

  • 4. Small knowledge points

    • Objects are GameObject objects
    • Scripts generally write fields and methods
      • Do not write attributes (cannot be displayed in the editor)
      • Do not write the constructor (cannot access the main thread in the child thread)
    • output to the console
      • Debug.Log(“ ”)
    • If a component needs to be reused
      • Can be moved from the hierarchy panel to the project panel to make a prefab
      • The bold font of the prefab will not be modified with the modification of the prefab

• 2. Script life cycle

  • 1. name

    • Also called inevitable event, message Message
      • If you want to find an inevitable event, you can search for MonoBehaviour (the parent class of the script) in the unity manual
      • Execution order search script life cycle view

  • 2. Small method

    • serialized field
      • [SerializeField]
        • write above the field
      • Function: display private variables in the editor
    • hidden field
      • [HideInInspector]
    • Restricted range
      • [Range(0,100)]
        • limit to 0 to 100

  • 3. Initial stage

    • Awake
      • Execution timing: Execute once immediately after creating the game object
        • Script disabled also executes
      • private void Awake(){}
      • Priority over Start
        • Two objects hang scripts at the same time, and Awake executes first
      • Role: initialization
        • instead of the constructor
    • Start
      • Execution timing: Execute once after the script starts after the game object is created
      • private void Start(){}
      • Role: initialization
        • instead of the constructor
    • OnEnable
      • Called whenever the script object starts
      • private void OnEnable

  • 4. Physical stage

    • FixedUpdate
      • Execution time: After the script starts, the fixed time is called
      • The default update frequency is 0.02s
      • Suitable for physical manipulation of game objects
        • object movement, movement, rotation
        • Because the time is fixed, it will not be affected by rendering
          • The rendering time is not fixed (the amount of rendering per frame is different, and the performance of the machine is different)

  • 5. Game logic

    • Update
      • Execution time: render frame execution
      • The execution interval is not fixed
      • Applies to: Kitchen Game Logic
        • update map
    • LateUpdate
      • The delayed update is executed after the Update function is called
        • Executed only after one frame, at the same time
      • apply following logic
        • If Update is written, it may be executed first

  • 6. Input events

    • mouseover
      • OnMouseEnter
      • Move the mouse to the current Collider
    • mouse over
      • OnMouseOver
      • Called when the mouse passes over the current Collider
    • mouse out
      • OnMouseExit
      • Called when the mouse leaves the current Collider
    • mouse down
      • OnMouseDown
      • Called when the mouse presses the current Collider
    • mouse up
      • OnMouseUp
      • Called when the mouse is lifted by the current Collider

  • 7. Scene rendering

    • OnBecameVisible when visible
      • Called when the Mesh Renderer is visible on any camera
    • OnBecameInvisible when invisible
      • Called when the Mesh Renderer is not visible on any camera

  • 8. Closing phase

    • OnDisable when not available
      • This function is called when the object becomes unavailable or the attached game object is inactive
    • OnDestroy when destroyed
      • This function is called when the script is destroyed or the attached game object is destroyed
    • OnApplicationQuit when the program ends
      • Called when the application exits

• 3. Debugging

  • 1. Check whether the method is executed or not

    • Debug.Log("111")
      • The console output is the method call
      • print() is also available. print is a method of the MonoBehaviour class, which must be inherited as the parent class

  • 2. Watch the time change

    • Write a time variable, and then Time.time can see the time change on the script property
      • Write it in Update
    • Try not to use Debug.Log, or consume too much memory

  • 3. Start debugging

    • The script must be hung on the object first
    • vs pressing F5
    • Then start the unity point
    • When you want to debug, press pause
    • Go back to vs and add a breakpoint, and go back to unity single frame operation (right side of pause)
    • Then go back to VS and press F11

• 4. Animation

  • 1. Record animation

    • Add component Animation
    • create physical file
    • Add components in Animation
      • For example, rotate to add Rotate
    • Record and add keyframes, just change the parameters

  • 2. Statement

    • play animation
      • play
    • After the previous animation is finished, play the next animation
      • PlayQueued
    • Is there any animation playing
      • IsPlaying
    • play backwards
      • Change speed to -1
        • Animation[" animation name"].speed=-1
        • In order to facilitate modification, try to create a public variable at the top to provide the animation name
      • And you need to set the animation time to 1
        • Add a statement to judge whether it is at the end
          • ComponentName.isPlaying==false
        • Component name [animation name].time=component name [animation name].length
        • Otherwise the animation does not play, from 0 to 0

• 5. Common APIs

  • 1. Component component

    • The Component class provides the function of finding (current object, descendants, ancestors) components
    • this.GetComponet< component name>().Component content;
    • Material is the content inside the MeshRenderer component
    • Get all components of the current object
      • var variable name = this.GetComponents<Component>();
        • Add s to get all components
      • foreach(var item in variable name){Debug.Log(item.GetType());}
    • Get the specified type components of descendant objects (including yourself)
      • GetComponentInChildren<MeshRenderer>();
    • Get the specified type components of ancestor objects (including yourself)
      • GetComponentInParent<MeshRenderer>();

  • 2. Transform

    • Transform provides the function of finding (parent-child root) transformation components and manipulating the position, rotation and scaling of objects
    • Get the transformation component of the child object (not including itself)
      • foreach(Transform Child in transform){}
      • neither grandson
    • The position of the object relative to the world coordinate system
      • this.transform.position
      • this.transform.rotation
    • The position of the pivot point of the object relative to the parent object
      • this.transform.localPosition
      • this.transform.localRotation
    • Scale relative to parent object
      • this.transform.localScale
    • Object and model scaling (self scaling * parent object scaling)
      • this.transform.lossyScale
    • Move 1 meter to the z-axis of its own coordinate system
      • this.transform.Translate(0,0,1)
      • to rotate
        • this.transform.Rotate(0,0,1)
      • revolve around
        • this.transform.RotateAround(Vector3.zero,Vector3.up,1)
        • Rotate 1 degree around the y-axis at world coordinate 0
        • The z axis is forward, and the x axis is
    • Move 1 meter to the z-axis of the world coordinate system
      • this.transform.Translate(0,0,1,Space.Worle)
      • to rotate
        • this.transform.Rotate(0,0,1,Space.world)
    • Get the ancestor transform component
      • root object
        • this.transform.root
      • parent object
        • this.transform.parent
    • Set the parent object of the transform
      • this.transform.setParent( parent object，false or true);
      • Whether the following false or true changes the position relative to the world coordinates, the default is true
    • Find the child object of transform
      • Get the number of child objects
        • int count = this.transform.childCount
      • Get child objects by name
        • Transform childTF=this.transform.Find(" child object name")
      • Get child object by index
        • Transform childTF = this.transform.GetChild(i)
    • Find subchildren when hierarchy is unknown
      • recursion
      • know the number of children
        • Transform parent node.childCount
      • own components
        • this.transform

  • 3. GameObject

    • activate or not
      • is actually activated
        • this.gameObject.activeInHierarchy
      • Whether the local is activated (read-only), whether the object is disabled in the Insoector
        • this.gameObject.activeSelf
      • Set object enable/disable
        • this.gameObject.SetActive()
      • add components
        • ObjectName.gameObject.AddComponent<Light>()
      • Find objects by name in the scene (deprecated)
        • GameObject.Find(" Game Object Name")
        • Finding a needle in a haystack costs performance
      • Find by label
        • Get all objects with this tag
          • GameObject[] allEnemy = GameObject.FindGameObjectsWithTag("标签名")
        • Get objects with this tag (single)
          • GameObject Enemy=GameObject.FindWithTag("标签名")

  • 4. Object

    • Delete game objects, components or resources
      • Destroy
    • Find objects by type
      • Object.FindObjectOfType<MeshRenderer>()
      • find all objects
        • Object.FindObjectsOfType<MeshRenderer>()

  • 5. Time

    • Elapsed time since now (read only)
      • Time.time
    • Time interval in seconds to complete the last frame (read only)
      • Time.deltaTime
    • Ensure movement speed is independent of render time
      • Premise: write code in update
        • Generally, the speed is multiplied by time to ensure that the rotation speed is not affected by its performance and rendering volume
        • 例如this.transform.Rotate(0,speed*Time.deltaTime,0)
          • rotation speed * render interval
      • Run in FixedUpdate without multiplying the time interval
        • this.transform.Rotate(0,speed,0)
    • game paused
      • time scaling
        • timeScale
          • Pause when it is 0
          • 1 at the original speed
          • no effect on rendering
        • unscaledDeltaTime is not affected by this
          • DeltaTime is affected by this
    • Individual statements are executed once at specified intervals
      • Set a variable to represent the next modification time (be more flexible, do it as soon as you come up, and wait until you finish it)
        • Time.time will be modified after this time
        • Then the variable is time+interval
      • Set a variable to represent the accumulated time (be more flexible, just wait when you come up, and do it after waiting)
        • Accumulate with Time.deltaTime
        • Modify beyond the interval
        • then accumulate to zero
      • Call the method repeatedly (suitable for fixed time intervals)
        • call in start
        • InvokeRepeating ( method name, first execution time, execution interval)
        • end repeated calls
        • CancelInvoke( method name)
      • Execute at specified time

         

        • Called in Start
        • Invoke (method name, first execution time)

        • 

          mind Mapping