Ray Ray
Today I want to summarize the Unity about ray related things, if there is some misunderstanding also hope to correct, thank you!
1. What Ray rays
First, we need to know the two components of a ray: origin and direction, so we need these parameters to instantiate a ray.
Ray instantiation:
Ray (Vector3 Origin,Vector3 direction) = new (Vector3 origin,Vector3 direction);
The first parameter origin indicates the starting point of the ray, and the second parameter direction indicates the direction of the ray.
2. Introduction of RaycastHit class
Function: Used to store collision information generated by emission rays. Common member variables are:
Point: Coordinates of the intersection of ray and collider
Collider: The object that collides with a ray
Distance: Coordinates of the ray starting point to the point of intersection with the colliding object
3. Ray debugging (display)
Debug.DrawRay(Vector3 start, Vector3 dir, Color color, float duration)
Dir: direction of the ray color: color of the ray during debugging duration: duration of the ray during debugging
The debug. DrawRay function has a lot of overloading. For example, we can not write “Color”, “Color”, “float duration”, then when we are in edit mode, the ray Color is white by default, and the lifetime is one frame by default.
Place the script below on an object, run it, and in edit mode you will see a red ray starting at (0,0,0) in the positive X-axis direction.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Shoot : MonoBehaviour
{
void Update()
{
Vector3 origin = new Vector3(0.0.0);
Vector3 direction = new Vector3(1f.0.0);
Ray ray = new Ray(origin, direction);
Debug.DrawRay(ray.origin, ray.direction * 100f, Color.red, 1f); }}Copy the code
Parameter ray: ray
Parameter hitInfo: Stores information about objects hit by rays
Parameter maxDistance: The maximum distance of the ray
Parameter layerMask: Ray detection layer, with int decimal conversion to binary judgment, (decimal)2->(binary)10, indicating the first layer of inspection TransparentFX;
Parameter QueryTriggerInteraction: query whether Ignore is the Trigger (Trigger), Ignore use QueryTriggerInteraction. Ignore, detection using QueryTriggerInteraction. Collide
If this ray touches another object with a collider on the specified layer, store the object information in hitInfo and return true. If it does not touch the object, return false.
Of course, this function has other overloads. For example, we can not write float maxDistance, int layerMask, QueryTriggerInteraction, so the maximum distance emitted is infinite by default, Layer 2 layer in addition to the default examination Ignore Raycast outside of the other layers, parameters for QueryTriggerInteraction QueryTriggerInteraction. UseGlobal, is set up inside the default Settings for our project. If checked, default detection, otherwise ignored;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Rayshoot : MonoBehaviour
{
bool isnoShoot;
public Vector3 Direction;
// Update is called once per frame
void Update()
{
// Input.getMouseButtonDown (0) Click the left mouse button to return true, otherwise return false
isnoShoot = Input.GetMouseButtonDown(0);
// Shoot();
if (isnoShoot)
{
Vector3 origin = new Vector3(0.0.0);
Vector3 direction = new Vector3(1f.0.0);
Ray ray = new Ray(origin, direction);
// an example of a ray starting at (0,0,0) with a positive direction along the X axis
Debug.DrawRay(ray.origin, ray.direction * 100f, Color.red, 1f);
RaycastHit hit;
Physics.Raycast(ray, out hit, 100f.1, QueryTriggerInteraction.Collide); Debug.Log(hit.collider); }}}Copy the code
Application scenario of ray
There are a lot of scenarios for ray-shooting, but due to space constraints, we will simulate the character shooting.
First we need to create a spherical collider in the scene, then drag it to the preform, then delete the spherical collider in the scene, and then add the following script to the preform.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class bullet : MonoBehaviour
{
Vector3 shootdirection;
float speed;
// Start is called before the first frame update
void Start()
{
speed = 6f;
}
// Update is called once per frame
void Update()
{
transform.Translate(shootdirection*speed*Time.deltaTime,Space.World);
}
/// <summary>
///Initializes the direction of bullet movement
/// </summary>
/// <param name="shoot"></param>
public void startState(Ray shoot){ shootdirection = shoot.direction; }}Copy the code
Then we created a spherical collider to simulate the character in the scene and added the following script to it.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class roleshoot : MonoBehaviour
{
bool isnoShoot;
public bullet bullets;
// Update is called once per frame
void Update()
{
isnoShoot = Input.GetMouseButtonDown(0);
if(isnoShoot) { RoleShoot(); }}void RoleShoot()
{
// The camera emits rays where the mouse is
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
RaycastHit hit;// Define a RaycastHit that accepts information about the object being hit
// Emit rays
Physics.Raycast(ray, out hit, 100f.1, QueryTriggerInteraction.Collide);
Vector3 shootdirection = hit.point - transform.position;
// The ray that the main character should emit
Ray roleray = new Ray(transform.position, shootdirection);
// Make ray visible in edit mode
Debug.DrawRay(roleray.origin, roleray.direction*1000f, Color.red, 2f);
// Generate bullets,
bullet bullet = Instantiate(bullets, transform.position, bullets.gameObject.transform.rotation);
// Initialize bullet orientationbullet.startState(roleray); }}Copy the codeThen add the preform manually.
