1 using UnityEngine;
2 using System.Collections;
3 using System.Collections.Generic;
4 [ExecuteInEditMode]
5 public class Parabola : MonoBehaviour {
6 //重力
7 [Range(0,1)]
8 public float gravity = 0.13f;
9 //最大长度
10 public float maxLength = 50;
11 //两点之间的距离
12 const float length = 0.2f;
13 //点集合
14 List<Vector3> m_List = new List<Vector3>();
15 Material m_LineMat;
16
17 public void OnRenderObject() {
18 CreateLineMaterial();
19 m_LineMat.SetPass(0);
20
21 Vector3 position = transform.position;
22 Vector3 forward = transform.rotation * Vector3.forward * length;
23 Vector3 newPos = position;
24 Vector3 lastPos = newPos;
25 m_List.Add(newPos);
26 int i = 0, iMax = 0;
27 float dis = 0;
28 while (dis < maxLength) {
29 i++;
30 newPos = lastPos + forward + Vector3.up * i * -gravity * 0.1f;
31 dis += Vector3.Distance(lastPos, newPos);
32 m_List.Add(newPos);
33 lastPos = newPos;
34 }
35
36 GL.Begin(GL.LINES);
37 i = 0;
38 iMax = m_List.Count;
39 for (i = 0; i < iMax; i++) {
40 GL.Vertex(m_List[i]);
41 }
42 GL.End();
43
44 m_List.Clear();
45 }
46
47 void CreateLineMaterial() {
48 if (!m_LineMat) {
49 var shader = Shader.Find("Hidden/Internal-Colored");
50 m_LineMat = new Material(shader);
51 m_LineMat.hideFlags = HideFlags.HideAndDontSave;
52 m_LineMat.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
53 m_LineMat.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
54 m_LineMat.SetInt("_Cull", (int)UnityEngine.Rendering.CullMode.Off);
55 m_LineMat.SetInt("_ZWrite", 0);
56 }
57 }
58 }
