Tag: rotate to face object

Here are scripts to help with AI for
Autopilot
Rotate to face an object
Calculate distance between two objects
Calculate angle of two objects

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

// A very simplistic car driving on the x-z plane.

public class Drive : MonoBehaviour
{
    
    public float speed = 10.0f;
    float autoPilotSpeed = 5.0f;
    public float rotationSpeed = 100.0f;
    public GameObject gasCan;
    bool autoPilotMode = false;

  

    // mathematical equations for AI machine learning------------------------

    void CalculateDistance()
    {
        Vector3 tankPosition = this.transform.position;
        Vector3 gasCanPosition = gasCan.transform.position;

        float distance = Mathf.Sqrt(Mathf.Pow(tankPosition.x - gasCanPosition.x,2) + Mathf.Pow(tankPosition.y - gasCanPosition.y,2) + Mathf.Pow(tankPosition.z - gasCanPosition.z, 2));

        float unityDistance = Vector3.Distance(tankPosition, gasCanPosition);   

        Debug.Log("Distance: " + distance.ToString());
        Debug.Log("Unity Distance: " + unityDistance.ToString());
    }


    void CalculateAngle()
    {
        Vector3 tankAngle = this.transform.up;
        Vector3 gasCanAngle = gasCan.transform.position - this.transform.position;

        float dot = tankAngle.x * gasCanAngle.x + tankAngle.y * gasCanAngle.y;// this didnt work, not correct
        float angle = Mathf.Acos(dot / (tankAngle.magnitude * gasCanAngle.magnitude));

        Debug.Log("Angle: " + angle * Mathf.Rad2Deg);
        Debug.Log("Unity Angle: " + Vector3.Angle(tankAngle, gasCanAngle)); ;

        Debug.DrawRay(this.transform.position, tankAngle * 10, Color.green, 2);
        Debug.DrawRay(this.transform.position, gasCanAngle, Color.red, 2);

        int clockwise = 1;
        if(GetCrossProduct(tankAngle, gasCanAngle).z < 0)
        {
            clockwise = -1;
        }

        float unityAngle = Vector3.SignedAngle(tankAngle, gasCanAngle, this.transform.forward);

        this.transform.Rotate(0,0,unityAngle);
    }

  

    Vector3 GetCrossProduct(Vector3 v, Vector3 w)
    {
        float xMult = v.y * w.z - v.z * w.y;
        float yMult = v.z * w.x - v.x * w.z;
        float zMult = v.x * w.y - v.y * w.x;

        Vector3 crossProd = new Vector3(xMult, yMult, zMult);

        return crossProd;

    }

    //---------------------------------------------------------
    //**********useful functions for ai and movement***********
    //******************************************
    //using AI, rotate gameobject toward a target/// pass in the vector 3 of two game objects 
    void rotateToTarget(GameObject targetObject)
    {
        Vector3 whoIslooking = this.transform.up;
        Vector3 targetObjectAngle = targetObject.transform.position - this.transform.position; 
        float unityAngle = Vector3.SignedAngle(whoIslooking, targetObjectAngle, this.transform.forward);

        this.transform.Rotate(0, 0, unityAngle);
    }
    //---------------------------------------------------
    //----------------------------------------------
    //*********calculate the distance to an object***********
    //********* returns a float of the distance between this game object and a target object
    float distanceToTarget(GameObject targetObject)
    {
        return Vector3.Distance(this.transform.position, targetObject.transform.position);
    }
    //-----------------------------------------------------------------
    //----------------------------------------------------------------
    //*******************Use AI to rotate to a target and move there******
    //**** not very good yet doesnt account for obstacles etc, 
    //uses a speed float var
    void AutoPilot(float autoPilotSpeed, GameObject targetGameObject)
    {
        rotateToTarget(targetGameObject);
        this.transform.Translate(this.transform.up * autoPilotSpeed, Space.World);

    }


    void Update()
    {
        // Get the horizontal and vertical axis.
        // By default they are mapped to the arrow keys.
        // The value is in the range -1 to 1
        float translation = Input.GetAxis("Vertical") * speed;
        float rotation = Input.GetAxis("Horizontal") * rotationSpeed;

        // Make it move in meters per second instead of meters per frame...
        translation *= Time.deltaTime;
        rotation *= Time.deltaTime;

        // Move translation along the object's z-axis
        transform.Translate(0, translation, 0);

        // Rotate around our y-axis
        transform.Rotate(0, 0, -rotation);

        if (Input.GetKeyDown(KeyCode.Space))
        {
            CalculateDistance();
            CalculateAngle();
        }

        if (Input.GetKeyDown(KeyCode.R))
        {
            rotateToTarget(gasCan);
            Debug.Log("Rotating to face " + gasCan.name);
        }

        if (Input.GetKeyDown(KeyCode.D))
        {
            Debug.Log("Deedubs distance: " + distanceToTarget(gasCan));
        }

        if (Input.GetKeyDown(KeyCode.P))
        {
            autoPilotMode = !autoPilotMode;
            if (autoPilotMode) AutoPilot(autoPilotSpeed, gasCan);
        }


    }
}