Unity3D OpenGL实现画符功能
发表于2018-07-09
本篇文章主要和大家分享Unity3D用OpenGL实现画符的功能，仅供参考。
一、实现一笔画符
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class DrawFu : MonoBehaviour ｛
//第一步 屏幕写东西
//1.记录屏幕上画的点 List 存储 鼠标输入点
//1.1 视图坐标系 以屏幕分辨率大小为参考物(1024*768) 右上角(1,1) 左下角(0,0) UV坐标系
//1.2 屏幕坐标系 以屏幕分辨率大小为参考物(1024*768) 右上角(1024,768,0) 左下角(0,0,0)
//1.3 世界坐标系 以(0,0,0) 为起点
//1.4 物体坐标系 以 父类 为参考物
//2.显示点 输入点 链接起来
//2.1 放一个image 当做画布
//第二步 屏幕上写的东西映射到旗上
//1.在图片上生成对应的像素点
//2.将 图片放到旗上
private Image testImage;
//存储所有点
private List<Vector2> allPoints;
//
private Material targetMaterial;
private void Start()
｛
testImage = transform.GetComponent<Image>();
allPoints = new List<Vector2>();
targetMaterial = transform.GetComponent<Renderer>().material;
｝
private void Update()
｛
if (Input.GetMouseButton(0))
｛
//获得鼠标的视图坐标系坐标
Vector2 viewPoint = Camera.main.ScreenToViewportPoint(Input.mousePosition);
allPoints.Add(viewPoint);
｝
if (Input.GetMouseButtonUp(0))
｛
GenerateTexture();
｝
｝
public void GenerateTexture()
｛
Texture2D temTexture = new Texture2D(300, 400);
for (int i = 1; i < allPoints.Count; i++)
｛
//前一个点
Vector2 temPos = allPoints[i - 1];
//后一个点
Vector2 temBack = allPoints[i];
//插值100次
for (int j = 0; j < 100; j++)
｛
//插值的比例
float temxx = Mathf.Lerp(temPos.x, temBack.x, j / 100.0f);
//插值的比例
float temyy = Mathf.Lerp(temPos.y, temBack.y, j / 100.0f);
//得到所有的比例点
int xx = (int)(temTexture.width * temxx);
int yy = (int)(temTexture.width * temyy);
//赋值 画出点
temTexture.SetPixel(xx, yy, Color.red);
｝
｝
temTexture.Apply();
targetMaterial.SetTexture("_MainTex", temTexture);
allPoints.Clear();
｝
static Material lineMaterial;
static void CreateLineMaterial()
｛
if (!lineMaterial)
｛
// Unity has a built-in shader that is useful for drawing
// simple colored things.
Shader shader = Shader.Find("Hidden/Internal-Colored");
lineMaterial = new Material(shader);
lineMaterial.hideFlags = HideFlags.HideAndDontSave;
// Turn on alpha blending
lineMaterial.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
lineMaterial.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
// Turn backface culling off
lineMaterial.SetInt("_Cull", (int)UnityEngine.Rendering.CullMode.Off);
// Turn off depth writes
lineMaterial.SetInt("_ZWrite", 0);
｝
｝
// Will be called after all regular rendering is done
public void OnRenderObject()
｛
CreateLineMaterial();
// Apply the line material
lineMaterial.SetPass(0);
GL.PushMatrix();
//将透视投影改为正交投影
GL.LoadOrtho();
// 划线开始
GL.Begin(GL.LINES);
//划线颜色
GL.Color(Color.red);
for (int i = 1; i < allPoints.Count; i ++)
｛
//前一个点
Vector2 temPos = allPoints[i - 1];
//后一个点
Vector2 temBack = allPoints[i];
//起点
GL.Vertex3(temPos.x, temPos.y, 0);
//终点
GL.Vertex3(temBack.x, temBack.y, 0);
｝
//划线结束
GL.End();
GL.PopMatrix();
｝
｝
二、实现多笔画符 存在问题 暂时不对
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class DrawFu : MonoBehaviour ｛
//第一步 屏幕写东西
//1.记录屏幕上画的点 List 存储 鼠标输入点
//1.1 视图坐标系 以屏幕分辨率大小为参考物(1024*768) 右上角(1,1) 左下角(0,0) UV坐标系
//1.2 屏幕坐标系 以屏幕分辨率大小为参考物(1024*768) 右上角(1024,768,0) 左下角(0,0,0)
//1.3 世界坐标系 以(0,0,0) 为起点
//1.4 物体坐标系 以 父类 为参考物
//2.显示点 输入点 链接起来
//2.1 放一个image 当做画布
//第二步 屏幕上写的东西映射到旗上
//1.在图片上生成对应的像素点
//2.将 图片放到旗上
private Image testImage;
//存储所有点
private List<Vector2> allPoints;
//
private Material targetMaterial;
//笔画数
public int count = 2;
//记录已画笔数
private int temCount = 0;
private void Start()
｛
testImage = transform.GetComponent<Image>();
allPoints = new List<Vector2>();
targetMaterial = transform.GetComponent<Renderer>().material;
｝
private void Update()
｛
if (Input.GetMouseButton(0))
｛
//获得鼠标的视图坐标系坐标
Vector2 viewPoint = Camera.main.ScreenToViewportPoint(Input.mousePosition);
allPoints.Add(viewPoint);
｝
if (Input.GetMouseButtonUp(0))
｛
temCount++;
if (temCount == count)
｛
GenerateTexture();
｝
｝
｝
public void GenerateTexture()
｛
Texture2D temTexture = new Texture2D(300, 400);
for (int i = 1; i < allPoints.Count; i++)
｛
//前一个点
Vector2 temPos = allPoints[i - 1];
//后一个点
Vector2 temBack = allPoints[i];
//插值100次
for (int j = 0; j < 100; j++)
｛
//插值的比例
float temxx = Mathf.Lerp(temPos.x, temBack.x, j / 100.0f);
//插值的比例
float temyy = Mathf.Lerp(temPos.y, temBack.y, j / 100.0f);
//得到所有的比例点
int xx = (int)(temTexture.width * temxx);
int yy = (int)(temTexture.width * temyy);
//赋值 画出点
temTexture.SetPixel(xx, yy, Color.red);
｝
｝
temTexture.Apply();
targetMaterial.SetTexture("_MainTex", temTexture);
allPoints.Clear();
｝
static Material lineMaterial;
static void CreateLineMaterial()
｛
if (!lineMaterial)
｛
// Unity has a built-in shader that is useful for drawing
// simple colored things.
Shader shader = Shader.Find("Hidden/Internal-Colored");
lineMaterial = new Material(shader);
lineMaterial.hideFlags = HideFlags.HideAndDontSave;
// Turn on alpha blending
lineMaterial.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
lineMaterial.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
// Turn backface culling off
lineMaterial.SetInt("_Cull", (int)UnityEngine.Rendering.CullMode.Off);
// Turn off depth writes
lineMaterial.SetInt("_ZWrite", 0);
｝
｝
// Will be called after all regular rendering is done
public void OnRenderObject()
｛
CreateLineMaterial();
// Apply the line material
lineMaterial.SetPass(0);
GL.PushMatrix();
//将透视投影改为正交投影
GL.LoadOrtho();
// 划线开始
GL.Begin(GL.LINES);
//划线颜色
GL.Color(Color.red);
for (int i = 1; i < allPoints.Count; i ++)
｛
//前一个点
Vector2 temPos = allPoints[i - 1];
//后一个点
Vector2 temBack = allPoints[i];
//起点
GL.Vertex3(temPos.x, temPos.y, 0);
//终点
GL.Vertex3(temBack.x, temBack.y, 0);
｝
//划线结束
GL.End();
GL.PopMatrix();
｝
｝
来自：https://blog.csdn.net/battletiger/article/details/77868111