[unity3d] rocker

1 Demand fulfillment

        1） Demand fulfillment

• Drag the joystick ball with the mouse to control the movement of the tank ;
• Up, down, left and right buttons can also control tank movement , And the rocker ball also moves synchronously ;
• Right mouse button sliding , Control the tank steering ;
• The position of the camera above the back of the player , Always follow the player , Look directly in front of the player ;
• Click the left mouse button to control the tank to launch shells .

        2） It's about the technology stack

• Transform Components
• human-computer interaction Input
• Rigid body components Rigidbody
• The camera follows
• Canvas Rendering mode and anchor
• UGUI And Image

• UGUI Callback function

2 The game object

        1） Game interface

        2） GameObject hierarchy

        3）Transform Component parameters

        1. The player  Transform Component parameters

Name	Type	Position	Rotation	Scale	Color/Texture
Player	Empty	(0, 0.25, -5)	(0, 0, 0)	(1, 1, 1)	#228439FF
Botton	Cube	(0, 0, 0)	(0, 0, 0)	(2, 0.5, 2)	#228439FF
Top	Cube	(0, 0.5, 0)	(0, 0, 0)	(1, 0.5, 1)	#228439FF
Gun	Cylinder	(0, 0, 1.5)	(90, 0, 0)	(0.2, 1, 0.4)	#228439FF
FirePoint	Empty	(0, 1.15, 0)	(0, 0, 0)	(1, 1, 1)	——

         Add ：Player Game object added rigid body components . 

        2. Ground and shells  Transform Component parameters

Name	Type	Position	Rotation	Scale	Color/Texture
Plane	Plane	(0, 0, 0)	(0, 0, 0)	(10, 10, 10)	GrassRockyAlbedo
Bullet	Sphere	(0, 0.5, -5)	(0, 0, 0)	(0.3, 0.3, 0.3)	#228439FF

        Add ： The shell is dragged as a preset body to Assets/Resources/Prefabs Under the table of contents , And added rigid body components .

        3. rocker RectTransform Component parameters

Name	Type	Width/Height	Pos	Anchors
Stick	Canvas	——	——	——
Background	Image	(100, 100)	(75, 75, 0)	(0, 0), (0, 0)
Ball	Image	(40, 40)	(75, 75, 0)	(0, 0), (0, 0)

3 Script components

        1）CameraController

        CameraController.cs

using UnityEngine;
 
public class CameraController : MonoBehaviour {
	private Transform player; //  The player 
	private Vector3 relaPlayerPos; //  The position of the camera in the player's coordinate system 
	private float targetDistance = 15f; //  The camera looks at the position in front of the player 
 
	private void Start() {
		relaPlayerPos = new Vector3(0, 4, -8);
		player = GameObject.Find("Player/Top").transform;
	}
 
	private void LateUpdate() {
		CompCameraPos();
	}
 
	private void CompCameraPos() { //  Calculate camera coordinates 
		Vector3 target = player.position + player.forward * targetDistance;
		transform.position = transformVecter(relaPlayerPos, player.position, player.right, player.up, player.forward);
		transform.rotation = Quaternion.LookRotation(target - transform.position);
	}
 
	//  Seeking for origin Origin , locX, locY, locZ  Is the vector in the local coordinate system of the coordinate axis  vec  The corresponding vector in the world coordinate system 
	private Vector3 transformVecter(Vector3 vec, Vector3 origin, Vector3 locX,  Vector3 locY,  Vector3 locZ) {
		return vec.x * locX + vec.y * locY + vec.z * locZ + origin;
	}
}

        explain ： CameraController The script component is hung on MainCamera On the object of the game .

        2）PlayerController

        PlayerController.cs

using System;
using UnityEngine;
 
public class PlayerController : MonoBehaviour {
	private Transform firePoint; //  Firing point 
	private GameObject bulletPrefab; //  Shell preset 
	private StickController stick; //  Rocker controls 
	private float tankMoveSpeed = 4f; //  Tank moving speed 
	private float tankRotateSpeed = 2f; //  The turning speed of the tank 
	private Vector3 predownMousePoint; //  Position when the mouse is pressed 
	private Vector3 currMousePoint; //  Current mouse position 
	private float fireWaitTime = float.MaxValue; //  The waiting time since the last firing 
	private float bulletCoolTime = 0.15f; //  Shell cooling time 

 	private void Start() {
		firePoint = transform.Find("Top/Gun/FirePoint");
		bulletPrefab = (GameObject) Resources.Load("Prefabs/Bullet");
		stick = GameObject.Find("Stick/Ball").GetComponent<StickController>();
	}

	private void Update() {
		Move();
		Rotate();
		Fire();
	}
 
	private void Move() { //  Tank movement 
		float hor = Input.GetAxis("Horizontal");
        float ver = Input.GetAxis("Vertical");
		Move(hor, ver);
	}

	public void Move(float hor, float ver) { //  Tank movement 
		if (Mathf.Abs(hor) > float.Epsilon || Mathf.Abs(ver) > float.Epsilon) {
			Vector3 vec = transform.forward * ver + transform.right * hor;
			GetComponent<Rigidbody>().velocity = vec * tankMoveSpeed;
			// stick.UpdateStick(new Vector3(hor, 0, ver));
			Vector3 dire = new Vector3(hor, ver, 0);
			dire =  dire.normalized * Mathf.Min(dire.magnitude, 1);
			stick.UpdateStick(dire);
		}
	}

	private void Rotate() { //  The tank rotates 
		if (Input.GetMouseButtonDown(1)) {
			predownMousePoint = Input.mousePosition;
		} else if (Input.GetMouseButton(1)) {
			currMousePoint = Input.mousePosition;
			Vector3 vec = currMousePoint - predownMousePoint;
			GetComponent<Rigidbody>().angularVelocity = Vector3.up * tankRotateSpeed * vec.x;
			predownMousePoint = currMousePoint;
		}
	}

	private void Fire() { //  The tank fired 
		fireWaitTime += Time.deltaTime;
		if (Input.GetMouseButtonDown(0) && !IsMouseInUIArea() || Input.GetKeyDown(KeyCode.Space)) {
			if (fireWaitTime > bulletCoolTime) {
				BulletInfo bulletInfo = new BulletInfo("PlayerBullet", Color.red, transform.forward, 10f, 15f);
				GameObject bullet = Instantiate(bulletPrefab, firePoint.position, Quaternion.identity);
				bullet.AddComponent<BulletController>().SetBulletInfo(bulletInfo);
				fireWaitTime = 0f;
			}
		}
	}

	private bool IsMouseInUIArea() { //  Mouse in UI Control area 
		Vector3 pos = Input.mousePosition;
		return pos.x < 150 && pos.y < 150;
	}
}

        explain ： PlayerController  The script component is hung on Player On the object of the game . 

        3）StickController

        StickController.cs

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

public class StickController : MonoBehaviour, IDragHandler, IEndDragHandler {
	private Vector3 originPos; //  Position when the mouse starts dragging 
	private Vector3 currPos; //  Current mouse position 
	private float radius; //  Remote rod radius 
	private PlayerController player; //  Player controller 
	private Vector3 dire = Vector3.zero; //  The orientation of the rocker ball 

	private void Start () {
		originPos = transform.position;
		radius = 50;
		player = GameObject.Find("Player").GetComponent<PlayerController>();
	}

	private void Update () {
		player.Move(dire.x, dire.y);
	}

	public void OnDrag(PointerEventData eventData) {
		Vector3 vec = Input.mousePosition - originPos;
		dire = vec.normalized * Mathf.Min(vec.magnitude / radius, 1);
		UpdateStick(dire);
	}

	public void OnEndDrag(PointerEventData eventData) {
		transform.position = originPos;
		dire = Vector3.zero;
	}

	public void UpdateStick(Vector3 dire) { //  Update the rocker position 
		transform.position = originPos + dire * radius;
	}
}

        explain ： StickController The script component is hung on Ball On the object of the game .  

        4）BulletController

        BulletController.cs

using UnityEngine;
using UnityEngine.UI;

public class BulletController : MonoBehaviour {
	private BulletInfo bulletInfo; //  Shell information 

	private void Start () {
		gameObject.name = bulletInfo.name;
		GetComponent<MeshRenderer>().material.color = bulletInfo.color;
		float lifeTime = bulletInfo.fireRange / bulletInfo.speed; //  Survival time 
		Destroy(gameObject, lifeTime);
	}

	private void Update () {
		transform.GetComponent<Rigidbody>().velocity = bulletInfo.flyDir * bulletInfo.speed;
	}

	public void SetBulletInfo(BulletInfo bulletInfo) {
		this.bulletInfo = bulletInfo;
	}
}

        explain ： BulletController The script component is hung on Bullet On the object of the game （ Dynamic addition in the code ）.   

        5）BulletInfo

        BulletInfo.cs

using UnityEngine;

public class BulletInfo {
	public string name; //  Shell name 
	public Color color; //  Shell color 
	public Vector3 flyDir; //  The direction in which the shell flew 
	public float speed; //  Projectile speed 
	public float fireRange; //  Shell range 

	public BulletInfo(string name, Color color, Vector3 flyDir, float speed, float fireRange) {
		this.name = name;
		this.color = color;
		this.flyDir = flyDir;
		this.speed = speed;
		this.fireRange = fireRange;
	}
}

4 Running effect