C# for UNITY3d: Sem 1 a.k.a. The Gospel of Mark Part 1

Transcription

1 C# for UNITY3d: Sem 1 a.k.a. The Gospel of Mark Part 1 Special Thanks to Mark Hoey, whose lectures this booklet is based on Move and Rotate an Object (using Transform.Translate & Transform.Rotate)...1 Random Color...2 Move, Jump and Rotate an Object (uses Rigidbody to move & jump-includes 2 methods to prevent double jumps)...3 Throw a Weapon (a rigid body) uses a timer to prevent rapid firing...5 Instantiating (spawning) Objects using a for loop...6 Destroy or Reposition Instantiated Objects...8 Change Levels (scenes) & Quit Application...8 Binding UI elements to variables...9 Triggers, Collisions & Importing Scripts and variables Nav Mesh Agent Change Animation State using Animator Arrays Example Script Three Scripts for Camera Follow, Mouse Orbit & Player Movement Ray Cast Example Script... 20

2 Move and Rotate an Object (using Transform.Translate & Transform.Rotate) This script is attached to the Player. public class MoveRotate: MonoBehaviour void Start () void Update () float movex = Input.GetAxis ("Horizontal") / 10f; float movez = Input.GetAxis ("Vertical") / 10f; transform.translate (movex, 0, movez); if (Input.GetAxis ("Horizontal")<0) transform.rotate(0f,- 2,0f); if (Input.GetAxis ("Horizontal")>0) transform.rotate(0f,2,0f); The Set Up Create an object (e.g. Cube), Give it a name. Add a Rigid Body Component Either Turn Gravity off OR Create a floor using a plane or a flattened cube 1

3 Random Color This script is attached to the object. Object Changes color when Ctrl is pressed public class ChangeColour : MonoBehaviour void Start () gameobject.getcomponent<renderer> ().material.color = new Color (Random.Range (0, 1f), R andom.range (0, 1f), Random.Range (0, 1f)); void Update () if (Input.GetButtonDown ("Fire1")) gameobject.getcomponent<renderer> ().material.color = new Color (Random.Range (0, 1f), Random.Range (0, 1f), Random.Range (0, 1f)); 2

4 Move, Jump and Rotate an Object (uses Rigidbody to move & jump- includes 2 methods to prevent double jumps) This is a better method in preventing payer from passing through objects. The script includes 2 methods to prevent double jump public class MoveWithForce : MonoBehaviour float thrust=5f; int jumpspeed=150; Rigidbody rb; public GameObject myfloor; //Ray private Ray myray; public Color raycolor; //RayCast RaycastHit objecthit; void Start() rb = GetComponent<Rigidbody>(); void FixedUpdate() rb.moveposition(transform.position + transform.forward * Time.deltaTime*Input.GetAxis(" Vertical")*thrust); if (Input.GetAxis ("Horizontal")<0) transform.rotate(0f,- 2,0f); if (Input.GetAxis ("Horizontal")>0) transform.rotate(0f,2,0f); Jump(); void Jump() //JUMP - CONTROLLING DOUBLE JUMP BY CHECKING DISTANCE FROM FLOOR - WORKS FINE /* if(transform.position.y - myfloor.transform.position.y<2) if(input.getbuttondown("fire1")) rb.addforce(transform.up * jumpspeed); */ 3

5 //CONTROL DOUBLE JUMP USING RAY CAST Vector3 down = transform.transformdirection(- Vector3.up) *2f; myray = new Ray (transform.position, down); Debug.DrawRay(transform.position, down, Color.green); Physics.Raycast(myRay,out objecthit, 2f); if(objecthit.collider.tag=="floor") Debug.Log("Jump"); if(input.getbuttondown("fire1")) rb.addforce(transform.up * jumpspeed); The Set Up Select the Player (object) Add a Rigid Body Component Either Turn Gravity off OR Create a floor using a plane or a flattened cube 4

6 Throw a Weapon (a rigid body) uses a timer to prevent rapid firing This script can be embedded or attached to a player or the the weapon itself public class ThrowWeapon : MonoBehaviour public Rigidbody weaponprefab; Rigidbody weapon; public Transform weaponpos; public float weaponspeed=600.0f; float mytime =1.0f; // Use this for initialization void Start () // Update is called once per frame void FixedUpdate () //Prevent Rapid Attacks using a Timer mytime += Time.deltaTime; if (Input.GetButtonDown ("Fire2")&&myTime>0.5f) Attack(); mytime = 0; void Attack() weapon = Instantiate (weaponprefab, weaponpos.position,weaponpos.rotation) as Rigidbody; weapon.addforce (weaponpos.transform.up * weaponspeed); 5

7 Instantiating (spawning) Objects using a for loop This script is attached an Empty Game Object public class MySpawner : MonoBehaviour public GameObject spawnobject1; public GameObject spawnobject2; public GameObject spawnobject3; // Use this for initialization void Start () Vector3 spawnpos; for (int i=0; i<=10; i++) spawnpos = new Vector3 (Random.Range (- 10f, 10f), 0f, Random.Range (- 10f, 10f)); Instantiate (spawnobject1, spawnpos, Quaternion.identity); spawnpos = new Vector3 (Random.Range (- 10f, 10f), 0f, Random.Range (- 10f, 10f)); Instantiate (spawnobject2, spawnpos, Quaternion.identity); spawnpos = new Vector3 (Random.Range (- 10f, 10f), 0f, Random.Range (- 10f, 10f)); Instantiate (spawnobject3, spawnpos, Quaternion.identity); The Set Up Create objects to be spawned Drag them into a folder called 'prefabs' Create an empty game object, rename it to GameScripts Create a new C# script and attach it to the empty game object called gamescripts Once the "public" GameObjects are defined, they will appear in the properties dialog box when the empty GameObject GameScripts is selected. Drag and Drop the objects to be spawned into the empty fields, example shown below If the prefab objects have gravity turned on they will fall 6

8 To get them to bounce off a plane or a floor- Add a 3D object Under Assets- >Create- >Physic Material, you can create an asset that imparts collision properties to rigid bodies Set the friction and bounce of this asset and drag it and drop it under the collider panel infront of the Material field for the object whose bounce you wish to set. (shown below) To kill objects under certain conditions, attach a script with the Destroy(gameObject); code to the objects themselves 7

9 Destroy or Reposition Instantiated Objects This script is attached the prefabs being instantiated void Update () if (transform.position.y < - 10) //Destroy (gameobject); DESTROYs THE gameobject transform.position = new Vector3 (Random.Range (- 10f,10f),Random.Range (20f,40f),Random.Range (- 10f,10f)); // gives it a new position in the same X-Z plane but different Y Change Levels (scenes) & Quit Application This script is attached to an Empty Game Object, which is dragged to the UI buttons TIP: Do not forget to add all scenes to Build Settings otherwise the change level scripts won't work & quit wont work in edit mode public class LevelChanger : MonoBehaviour public void ChangeLevel (string LevelName) Application.LoadLevel (LevelName); public void QuitGame () Application.Quit (); The Set Up This script is attached to an Empty Game Object. The Game Object is then dragged onto a UI Button. Clicking on Functions will pop up a list, choose the script that holds the scene changing code. Next choose the function name (in this case ChangeLevel). The public setting allows us to type the scene name in a small box that appears on the bottom right. 8

10 Binding UI elements to variables This script is attached the Player TIP: Do not forget to - using UnityEngine.UI; - Line 3 in the code below using UnityEngine.UI; public class MyHero : MonoBehaviour public string charactername; public bool charactermoving; public float characterpositionx; public int characterhealth; public int characterscore; public Text txtname; //UI Text public Text txtmoving; public Text txtposition; public Slider sldhealth; // UI Slider public Text txtscore; void Start () txtname.text = charactername; void Update () //Bind UI elements with variables, not some need to be converted to Text using ToString(); method txtmoving.text = charactermoving.tostring (); txtposition.text = characterpositionx.tostring (); sldhealth.value = characterhealth; txtscore.text = characterscore.tostring (); float xmovement = Input.GetAxis ("Horizontal") / 10; float ymovement = Input.GetAxis ("Vertical") / 10; transform.translate (xmovement, 0f, ymovement); characterpositionx = transform.position.x; if ((xmovement!=0 && ymovement!=0)) charactermoving = false; else charactermoving = true; 9

11 The Set Up Create the UI elements in a Canvas. - Text, Sliders, etc. Set up public variables in the code for charactername, characterhealth, characterlife etc. using string, int, bool etc whatever is appropriate e.g. public string charactername; public bool charactermoving; public float characterpositionx; public int characterhealth; TIP: Dont forget to add using UnityEngine.UI; Now set up public variables using UI data types to receive the information from these variables e.g. txtmoving.text = charactermoving.tostring(); txtposition.text = characterpositionx.tostring(); sldhealth.value = characterhealth; txtscore.text = characterscore.tostring (); After finishing up the script. Return to the inspector and drag and drop the UI elements to their corresponding UI variables One important step is to link the UI elements to the public variables in the GUI. See image below. Also, the same applies when one script reads variables of the other.(in next topic) 10

12 Triggers, Collisions & Importing Scripts and variables This script is attached the Player public class HeroHealth : MonoBehaviour public MyHero healthref; //this allows this script to refer to variables from myhero.cs void OnCollisionEnter (Collision myobject) if (myobject.gameobject.tag == "enemy") healthref.characterscore - = 10; healthref.characterhealth - = 20; void OnTriggerEnter (Collider myobject) if (myobject.gameobject.tag == "health") healthref.characterhealth += 20; healthref.characterscore += 10; Destroy (myobject.transform.gameobject); The Set Up A Player / Object (Hero) with a RigidBody component Script attached to player An object with colliders (should have a collider component) An object marked as a trigger (see image below) 11

13 Nav Mesh Agent This script is attached to the enemy objects public class Follow : MonoBehaviour private NavMeshAgent agent; public GameObject gethim; void Start () agent = GetComponent<NavMeshAgent> (); void Update () agent.setdestination (gethim.transform.position); The Set Up Choose Surface on which enemies shall follow Player Go to WIndow- >Navigation Choose Static Then Choose Bake tab and then hit the "Bake" button. Adjust step height, slopes etc to determine how the enemies respond Choose the enemy (plane, dog, villain, whatever) Add a component called Nav Mesh Agent Adjust his speed, stopping distance etc Add the script on the left Drag and drop the hero into the public variable dialog box to set the object being chased 12

14 Change Animation State using Animator This script is attached to the player public class PlayerMovement : MonoBehaviour //STEP 1 - Set Variable for animator component private Animator animator; // Use this for initialization void Start () //STEP 2 - Get theanimator component. It should be attached to object animator = GetComponent <Animator> (); // Update is called once per frame void Update () float fwd = Input.GetAxis ("Vertical") / 10f; transform.translate (0, 0, - fwd); float rot = Input.GetAxis ("Horizontal"); transform.rotate (0, rot, 0); //STEP 3 - If statements to set the parameter iswalking true and False if (fwd!= 0 rot!= 0) animator.setbool ("iswalking", true); else animator.setbool ("iswalking", false); // end if statement for animator The Set Up PART 1 Import your Max file with Animations OS X wont import the Max file directly, you will need to do an FBX export. But a PC will import directly Click on the animation, then click on "Edit" under the inspector and set the various animations by clicking on add (plus sign +) Set the start frame, end frame and loop if needed (e.g. for walk) PART 2 13

15 Right click on Assets and create an Animation Controller. If the Max file has attached an animator component, then drag this controller into the field which reads Animation COntroller or just drag into the inspector when the Player is selected and an animator will be aded automatically. Double click on the Animation Controller to open up the State Machine. Drag and drop the various animation states into this Right click on the default state and set that as the default An arrow from entry to this state will appear On the left side, Choose Parameters and click on + to add a parameter like 'Bool' and call it 'iswalking' On the right side right click on the idle state and choose create Transition, drag and drop to the walking state. When you click on the arrow, on the right side you can set that this occurs when the parameter iswalking is true and you can add a second transition the other way round and set the iswalking to False 14

16 Arrays Example Script Attach the script to an Empty Object. public class MyArrayScript : MonoBehaviour public GameObject[] objecttospawn; void Start () randomitem = Random.Range (0, objecttospawn.length); //gets a random number from 0 to array Length Instantiate (objecttospawn [randomitem], new Vector3 (0,0,0, Quaternion.identity); The Set Up Attach Script to an Empty Game Object Create a few prefab Objects Click on Emty Game Object. Click on triangle to Open Array Onject to Spawn Specify a number of objects Drag and Drop prefabs into the Array & Play 15

17 Three Scripts for Camera Follow, Mouse Orbit & Player Movement The Set Up Create a Hierarchy of Game Objects as shown below: o Camera (holds Script MouseOrbit.cs) o PlayerHolder (holds Script Player.cs)! Player! AimHere (holds Script MatchRotation.cs)! Sword! Shield etc Select Camera - Drag and Drop GameObject AimHere into public Transform Target) Select PlayerHolder - Drag and Drop GameObject AimHere into public Playergraphic Select AimHere - Drag and Drop GameObject Camera into public ObjectToMatchRotation MouseOrbit.cs /// <summary> /// Modified from: /// </summary> public class MouseOrbitImproved : MonoBehaviour public Transform target; float distance; public float xspeed = 120.0f; public float yspeed = 120.0f; public float yminlimit = - 20f; public float ymaxlimit = 80f; public float distancemin = 0.5f; public float distancemax = 15f; float x = 0.0f; float y = 0.0f; public float cameradistance = 5f; // Use this for initialization void Start() Vector3 angles = transform.eulerangles; x = angles.y; y = angles.x; distance = cameradistance; 16

18 void Update() if (target) x += Input.GetAxis("Mouse X") * xspeed * distance * 0.02f; y - = Input.GetAxis("Mouse Y") * yspeed * 0.02f; y = ClampAngle(y, yminlimit, ymaxlimit); Quaternion rotation = Quaternion.Euler(y, x, 0); distance = Mathf.Clamp(distance - Input.GetAxis("Mouse ScrollWheel") * 5, distancemin, distancemax); //A ray out from the target towards the camera to see Ray forwardray = new Ray(target.position, - transform.forward * cameradistance); //Draw the ray for debugging - not necessary Debug.DrawRay(target.position, - transform.forward * cameradistance); //Cast the ray to see if it's hitting an object and store the HIT details RaycastHit hit; Physics.Raycast(forwardRay, out hit, distance); //Cast a ray the distance the camera should be and if hitting an object use the //distance of HIT from the above raycast to determine where the camera should be if(physics.raycast(forwardray, cameradistance)) distance - = hit.distance / 20f; else if (distance < cameradistance) distance += 0.1f; Vector3 negdistance = new Vector3(0.0f, 0.0f, - distance); Vector3 position = rotation * negdistance + target.position; transform.rotation = rotation; transform.position = position; public static float ClampAngle(float angle, float min, float max) if (angle < - 360F) angle += 360F; if (angle > 360F) angle - = 360F; return Mathf.Clamp(angle, min, max); 17

19 Player.cs public class Player : MonoBehaviour public float speed = 2f; public Transform playergraphic; public GameObject camera; void Update() Movement(); void Movement() //Player object movement float hormovement = Input.GetAxisRaw("Horizontal"); float vertmovement = Input.GetAxisRaw("Vertical"); if (hormovement!= 0 && vertmovement!= 0) speed = 3f; else speed = 2f; transform.translate(camera.transform.right * hormovement * Time.deltaTime * speed); transform.translate(camera.transform.forward * vertmovement * Time.deltaTime * speed ); //These two Vector3's are needed to keep the player from rotating into the ground Vector3 forwardonlyxandz = new Vector3 ( camera.transform.forward.x * Input.GetAxis("Vertical"), 0, camera.transform.forward.x * Input.GetAxis("Vertical") ); Vector3 rightonlyxandz = new Vector3 ( camera.transform.right.z * Input.GetAxis("Horizontal"), 0, camera.transform.right.z * Input.GetAxis("Horizontal") ); //Player graphic rotation //Vector3 movedirection = new Vector3(horMovement, 0, vertmovement); Vector3 movedirection = forwardonlyxandz + rightonlyxandz; 18

20 if (movedirection!= Vector3.zero) Quaternion newrotation = Quaternion.LookRotation(moveDirection); playergraphic.transform.rotation = Quaternion.Slerp( playergraphic.transform.rotation, newrotation, Time.deltaTime * 8); //END HERE... unless using animations //Player graphic animation //SET BOOL TO SWITCH ANIMATIONS FOR MOVEMENT /* if (movedirection.magnitude > 0.05f) playergraphic.getcomponent<animator>().setbool("iswalking", true); else playergraphic.getcomponent<animator>().setbool("iswalking", false); */ MatchRotation.cs public class MatchRotation : MonoBehaviour public GameObject objecttomatchrotationwith; void Update() transform.rotation = objecttomatchrotationwith.transform.rotation; 19

21 Ray Cast Example Script Attach the script either a player or an enemy to detect. public class RayCastDemo : MonoBehaviour private Ray myray; public Transform testifhit; //This is a Sphere Object. Drag and Drop public Color raycolor; //This is a Color. Remember to set Aplha to >0 like 1 RaycastHit objecthit; public GameObject missile; //This is a prefab sword. Drag and Drop public Transform missilespawn; //This is a Empty Game object Indicating where the sword will instantiate public int missilespeed=100; float mytime; // Use this for initialization void Start () // Update is called once per frame void Update () myray = new Ray (transform.position,transform.forward*50); Debug.DrawRay (transform.position,transform.forward*50, raycolor); Physics.Raycast(myRay,out objecthit, 10f); if (objecthit.collider.tag=="hithim") Debug.Log ("FIRE"); Attack (); else Debug.Log ("STOP FIRE"); void Attack() GameObject clone=instantiate (missile, missilespawn.position, Quaternion.identity) as GameObject; clone.getcomponent<rigidbody>().addforce (new Vector3 (0, 0, missilespeed)); Destroy (clone, 5f); 20

22 The Set Up You basically need a player and an enemy. Attach the script to the Enemy You can drag and drop the player object into the public variable testifhit; TIP: I have attached swords (rectangular blocks as prefabs, that get intansiated when the Ray detects the player. I have just animated my Sphere, but you can get yours to move around 21