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/**
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* 流程图绘制方法集
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* 作者：刘广文
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* 邮箱：liugw@imut.edu.cn
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* 版本：20230813
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* 功能：基于canvas实现流程图的绘制
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*/
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var tool = 1;
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var current = -1;
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var flag=false;
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var mouseX= 0;
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var mouseY= 0;
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var mouseX1= 0;
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var mouseY1= 0;
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var aryPoint = [];
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var aryObject = [];
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//加载工具
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function loadTools(target){
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target.innerHTML = "<div id=\"begin\" onclick=\"clickTool(this, 1);\" title=\"绘制开始框\">开始</div>"
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+ "<div id=\"process\" onclick=\"clickTool(this, 2);\" title=\"绘制处理框\">处理</div>"
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+ "<div id=\"arrow\" onclick=\"clickTool(this, 3);\" title=\"绘制直线连接箭头\"></div>"
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+ "<div id=\"arrow1\" onclick=\"clickTool(this, 4);\" title=\"绘制折线连接箭头\"></div>"
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+ "<div id=\"judge\" onclick=\"clickTool(this, 5);\" title=\"绘制判断框\">条件？</div>"
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+ "<div id=\"end\" onclick=\"clickTool(this, 6);\" title=\"绘制结束框\">结束</div>"
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+ "<div id=\"led\" onclick=\"clickTool(this, 7);\" title=\"绘制显示框\">显示</div>"
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+ "<div id=\"link\" onclick=\"clickTool(this, 8);\" title=\"绘制连接框\">1</div>";
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}
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//鼠标抬起响应动作
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function myMouseUp(e, page){
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flag=false;
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pushTool(tool, mouseX, mouseY, mouseX1, mouseY1, text.value, color.value, bcolor.value, size.value);
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updateTools(cxt);
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}
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//鼠标移动响应动作
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function myMouseMove(e, page){
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mouseX1= e.pageX-page.offsetLeft;
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mouseY1= e.pageY-page.offsetTop;
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if(flag){
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var aryPoint1 = [];
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var i = 0;
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while(i < aryPoint.length){
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aryPoint1.push(aryPoint[i]);
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i ++;
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}
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updateTools(cxt);
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aryPoint = [];
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i = 0;
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while(i < aryPoint1.length){
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aryPoint.push(aryPoint1[i]);
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i ++;
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}
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if (tool == 4){
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var s = aryPoint[aryPoint.length - 1];
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ary = s.split(",");
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var x = parseFloat(ary[0]), y = parseFloat(ary[1]);
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if (Math.abs(x - mouseX1) > 10 || Math.abs(y - mouseY1) > 10)
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aryPoint.push(mouseX1 + "," + mouseY1);
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}
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drawTool(cxt, tool, mouseX, mouseY, mouseX1, mouseY1, color.value, bcolor.value, size.value);
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}
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}
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//鼠标按下响应动作
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function myMouseDown(e, page)
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{
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mouseX= e.pageX-page.offsetLeft;
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mouseY= e.pageY-page.offsetTop;
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aryPoint = [];
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aryPoint.push(mouseX + "," + mouseY);
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flag=true;
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}
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//保存
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function save(){
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var ary = [];
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var i = 0;
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while(i <= current){
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ary.push(aryObject[i]);
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i ++;
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}
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aryObject = ary;
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updateButton();
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const fileName = 'flowchart.txt';
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var str = '';
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i = 0;
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while(i < aryObject.length){
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if (i == 0)
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str = aryObject[i]
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else{
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str += "\r\n"
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str += aryObject[i]
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}
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i ++;
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}
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const content = str
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const blob = new Blob([content], {type: 'application/text'});
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// 构造一个blob对象来处理数据
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// 对于<a>标签，只有 Firefox 和 Chrome（内核） 支持 download 属性
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// IE10以上支持blob但是依然不支持download
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if ('download' in document.createElement('a'))
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{
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// 支持a标签download的浏览器
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const link = document.createElement('a')
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// 创建a标签
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link.download = fileName
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// a标签添加属性
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link.style.display = 'none'
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link.href = URL.createObjectURL(blob)
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document.body.appendChild(link)
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link.click()
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// 执行下载
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URL.revokeObjectURL(link.href)
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// 释放url
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document.body.removeChild(link)
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// 释放标签
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} else {
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// 其他浏览器
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navigator.msSaveBlob(blob, fileName)
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}
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}
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//撤销
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function undo(){
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if (current >= 0)
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{
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current --;
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updateTools();
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}
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updateButton();
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}
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//刷新按钮状态
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function updateButton(){
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var undo = document.getElementById("undo");
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var redo = document.getElementById("redo");
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var save = document.getElementById("save");
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if (current >= 0)
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{
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save.disabled = false;
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undo.disabled = false;
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}
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else
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{
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undo.disabled = true;
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save.disabled = true;
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}
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if (current < aryObject.length - 1)
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{
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redo.disabled = false;
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}
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else {
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redo.disabled = true;
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}
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}
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//重做
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function redo(){
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if (current < aryObject.length - 1)
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{
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current ++;
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updateTools();
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}
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updateButton();
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}
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//选择工具
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function clickTool(o, tag){
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tool = tag;
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for(var i = 0; i < tools.children.length; i ++){
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tools.children[i].style.border = '1px solid black';
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}
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o.style.border = '2px solid red';
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text.hidden = true;
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text.value = "";
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if (tag == 1)
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{
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text.hidden = false;
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text.value = "开始";
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}
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if (tag == 2)
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{
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text.hidden = false;
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text.value = "处理";
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}
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if (tag == 3 || tag == 4){
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text.hidden = false;
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text.value = "";
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}
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if (tag == 5)
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{
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text.hidden = false;
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text.value = "条件";
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}
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if (tag == 6)
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{
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text.hidden = false;
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text.value = "结束";
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}
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if (tag == 7)
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{
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text.hidden = false;
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text.value = "显示信息";
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}
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if (tag == 8)
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{
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text.hidden = false;
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text.value = "1";
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}
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}
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//绘制所有工具
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function updateTools(context){
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canvas.width = canvas.width;
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var i = 0;
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while (i <= current){
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var ary = aryObject[i].split('|');
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var type = parseInt(ary[0]);
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var ary1 = ary[1].split(',');
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var x1 = parseFloat(ary1[0]);
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var y1 = parseFloat (ary1[1]);
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var x2 = parseFloat(ary1[2]);
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var y2 = parseFloat(ary1[3]);
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var size = parseFloat(ary[5]);
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var color = ary[3];
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var bcolor = ary[4];
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if(type == 4){
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x2 = parseFloat(ary1[ary1.length - 2]);
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y2 = parseFloat(ary1[ary1.length - 1]);
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aryPoint = [];
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var j = 0;
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while(j < ary1.length){
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var x = parseFloat(ary1[j]), y = parseFloat(ary1[j + 1]);
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aryPoint.push(x + "," + y);
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j += 2;
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}
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}
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drawTool(cxt, type, x1, y1, x2, y2, color, bcolor, size);
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drawText(cxt, type, x1, y1, x2, y2, ary[2], color);
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i ++;
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}
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}
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//保存当前的绘制
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function pushTool(type, x1, y1, x2, y2, text, color, bcolor, size){
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var ary = [];
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var i = 0;
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while(i <= current){
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ary.push(aryObject[i]);
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i ++;
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}
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aryObject = ary;
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var s = type + '|' + x1 + ',' + y1 + ',' + x2 + ',' + y2 + '|' + text + '|' + color + '|' + bcolor + '|' + size;
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if(type == 4){
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s = type + '|';
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i = 0;
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while(i < aryPoint.length){
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if (i > 0)
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s += ",";
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s += aryPoint[i];
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i ++;
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}
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s = s + '|' + text + '|' + color + '|' + bcolor + '|' + size;
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}
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aryObject.push(s);
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current ++;
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updateButton();
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}
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//绘制文本
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function drawText(context, type, x1, y1, x2, y2, text, color){
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if (text == "" || context == null || type < 1) return;
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switch(type){
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case 1:
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case 2:
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case 5:
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case 6:
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case 7:
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case 8:{
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//绘制开始框
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//计算宽高
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var l = x1, t = y1;
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var w = x2 - x1, h = y2 - y1;
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if (w < 0)
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{
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l = x2;
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w = x1 - x2;
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}
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if (h < 0){
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t = y2;
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h = y1 - y2;
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}
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context.font = "10pt SimSun";
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//updateFont(context, w, h, text, 100);
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var w1 = getFontWidth(context, text);
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var h1 = getFontHeight(context, text);
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context.fillStyle = color;
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context.fillText(text, l + (w - w1) / 2, t + h1 / 4 + h / 2);
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break;
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}
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case 3:{
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//绘制箭头
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//计算文字大小
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context.font = "10pt SimSun";
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var w = getFontWidth(context, text);
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var h = getFontHeight(context, text);
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//获得输出坐标
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var x = (x2 + x1) / 2;
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var y = (y2 + y1) / 2;
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context.fillStyle = color;
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context.fillText(text, x, y);
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break;
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}
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case 4:{
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//绘制箭头
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//计算文字大小
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context.font = "10pt SimSun";
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var w = getFontWidth(context, text);
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var h = getFontHeight(context, text);
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//获得输出坐标
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var px1 = x1, py1 = y1;
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var i = 1;
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var pp = 0;
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while(i < aryPoint.length)
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{
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var ary = aryPoint[i].split(',');
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var px = parseFloat(ary[0]), py = parseFloat(ary[1]);
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var pp1 = 2;
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if (Math.abs(px - px1) > Math.abs(py - py1)) pp1 = 1;
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if (pp != 0 && pp1 != pp) break;
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pp = pp1;
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px1 = px;
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py1 = py;
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i ++;
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}
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var x = (px1 + x1) / 2;
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var y = (py1 + y1) / 2;
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context.fillStyle = color;
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context.fillText(text, x, y);
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break;
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}
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}
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}
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//绘制当前工具
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function drawTool(context, type, x1, y1, x2, y2, color, bcolor, size){
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if (context == null || type < 1) return;
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switch(type){
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case 1:{
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//绘制开始框
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//计算宽高
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var l = x1, t = y1;
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var w = x2 - x1, h = y2 - y1;
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if (w < 0)
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{
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l = x2;
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w = x1 - x2;
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}
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if (h < 0){
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t = y2;
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h = y1 - y2;
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}
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context.strokeStyle = color;
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context.lineWidth = size;
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context.beginPath();
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context.moveTo(l, t + h / 2);
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context.lineTo(l + w * 0.15, t);
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context.lineTo(l + w - w * 0.15, t);
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context.lineTo(l + w, t + h / 2);
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context.lineTo(l + w - w * 0.15, t + h);
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context.lineTo(l + w * 0.15, t + h);
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context.lineTo(l, t + h / 2);
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context.closePath();
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context.fillStyle = bcolor;
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context.fill();
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context.stroke();
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break;
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}
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case 2:{
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//绘制处理框
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//计算宽高
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var l = x1, t = y1;
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var w = x2 - x1, h = y2 - y1;
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if (w < 0)
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{
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l = x2;
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w = x1 - x2;
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}
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if (h < 0){
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t = y2;
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h = y1 - y2;
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}
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context.strokeStyle = color;
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context.lineWidth = size;
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context.beginPath();
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context.moveTo(l, t);
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context.lineTo(l + w, t);
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context.lineTo(l + w, t + h);
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context.lineTo(l, t + h);
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context.lineTo(l, t);
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context.closePath();
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context.fillStyle = bcolor;
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context.fill();
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context.stroke();
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break;
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}
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case 3:{
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//绘制连接箭头
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//计算箭头方向
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var ll = 10, ss = 30;
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var a = Math.atan2((y2 - y1), (x2 - x1));
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var x3 = x2 - ll * Math.cos(a + ss * Math.PI/180);
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var y3 = y2 - ll * Math.sin(a + ss * Math.PI/180);
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var x4 = x2 - ll * Math.cos(a - ss * Math.PI/180);
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var y4 = y2 - ll * Math.sin(a - ss * Math.PI/180);
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context.strokeStyle = color;
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context.lineWidth = size;
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context.beginPath();
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context.moveTo(x1, y1);
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context.lineTo(x2, y2);
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context.lineTo(x3, y3);
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context.moveTo(x2, y2);
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context.lineTo(x4, y4)
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context.closePath();
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context.stroke();
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break;
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}
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case 4:{
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//绘制折线连接箭头
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if (aryPoint.length < 3)
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break;
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var ary = aryPoint[aryPoint.length - 2].split(',');
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var px1 = parseFloat(ary[0]), py1 = parseFloat(ary[1]);
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ary = aryPoint[aryPoint.length - 1].split(',');
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|
var px2 = parseFloat(ary[0]), py2 = parseFloat(ary[1]);
|
|
|
if (Math.abs(px2 - px1) > Math.abs(py2 - py1))
|
|
|
py1 = py2;
|
|
|
else px1 = px2;
|
|
|
//计算箭头方向
|
|
|
var ll = 10, ss = 30;
|
|
|
var a = Math.atan2((py2 - py1), (px2 - px1));
|
|
|
var x3 = px2 - ll * Math.cos(a + ss * Math.PI/180);
|
|
|
var y3 = py2 - ll * Math.sin(a + ss * Math.PI/180);
|
|
|
var x4 = px2 - ll * Math.cos(a - ss * Math.PI/180);
|
|
|
var y4 = py2 - ll * Math.sin(a - ss * Math.PI/180);
|
|
|
context.strokeStyle = color;
|
|
|
context.lineWidth = size;
|
|
|
context.beginPath();
|
|
|
context.lineTo(px2, py2);
|
|
|
context.lineTo(x3, y3);
|
|
|
context.moveTo(px2, py2);
|
|
|
context.lineTo(x4, y4)
|
|
|
context.moveTo(px2, py2);
|
|
|
context.lineTo(px1, py1);
|
|
|
var i = aryPoint.length - 3;
|
|
|
while(i >= 0){
|
|
|
ary = aryPoint[i].split(',');
|
|
|
px2 = parseFloat(ary[0]), py2 = parseFloat(ary[1]);
|
|
|
if (Math.abs(px2 - px1) > Math.abs(py2 - py1))
|
|
|
py2 = py1;
|
|
|
else px2 = px1;
|
|
|
context.moveTo(px1, py1);
|
|
|
context.lineTo(px2, py2);
|
|
|
px1 = px2;
|
|
|
py1 = py2;
|
|
|
i --;
|
|
|
}
|
|
|
context.closePath();
|
|
|
context.stroke();
|
|
|
break;
|
|
|
}
|
|
|
case 5:{
|
|
|
//绘制判断框
|
|
|
//计算宽高
|
|
|
var l = x1, t = y1;
|
|
|
var w = x2 - x1, h = y2 - y1;
|
|
|
if (w < 0)
|
|
|
{
|
|
|
l = x2;
|
|
|
w = x1 - x2;
|
|
|
}
|
|
|
if (h < 0){
|
|
|
t = y2;
|
|
|
h = y1 - y2;
|
|
|
}
|
|
|
context.strokeStyle = color;
|
|
|
context.lineWidth = size;
|
|
|
context.beginPath();
|
|
|
context.moveTo(l, t + h / 2);
|
|
|
context.lineTo(l + w / 2, t);
|
|
|
context.lineTo(l + w, t + h / 2);
|
|
|
context.lineTo(l + w / 2, t + h);
|
|
|
context.lineTo(l, t + h / 2);
|
|
|
context.closePath();
|
|
|
context.fillStyle = bcolor;
|
|
|
context.fill();
|
|
|
context.stroke();
|
|
|
break;
|
|
|
}
|
|
|
case 6:{
|
|
|
//绘制结束框
|
|
|
//计算宽高
|
|
|
var l = x1, t = y1;
|
|
|
var w = x2 - x1, h = y2 - y1;
|
|
|
if (w < 0)
|
|
|
{
|
|
|
l = x2;
|
|
|
w = x1 - x2;
|
|
|
}
|
|
|
if (h < 0){
|
|
|
t = y2;
|
|
|
h = y1 - y2;
|
|
|
}
|
|
|
context.strokeStyle = color;
|
|
|
context.lineWidth = size;
|
|
|
var r = w * 0.4;
|
|
|
if (h < w)
|
|
|
r = h * 0.4;
|
|
|
context.beginPath();
|
|
|
context.moveTo(l + r, t);
|
|
|
context.arcTo(l + w, t, l + w, t + h, r);
|
|
|
context.arcTo(l + w, t + h, l, t + h, r);
|
|
|
context.arcTo(l, t + h, l, t, r);
|
|
|
context.arcTo(l, t, l + w, t, r);
|
|
|
context.closePath();
|
|
|
context.fillStyle = bcolor;
|
|
|
context.fill();
|
|
|
context.stroke();
|
|
|
break;
|
|
|
}
|
|
|
case 7:{
|
|
|
//绘制信息显示框
|
|
|
//计算宽高
|
|
|
var l = x1, t = y1;
|
|
|
var w = x2 - x1, h = y2 - y1;
|
|
|
if (w < 0)
|
|
|
{
|
|
|
l = x2;
|
|
|
w = x1 - x2;
|
|
|
}
|
|
|
if (h < 0){
|
|
|
t = y2;
|
|
|
h = y1 - y2;
|
|
|
}
|
|
|
context.strokeStyle = color;
|
|
|
context.lineWidth = size;
|
|
|
var r = w * 0.4;
|
|
|
if (h < w)
|
|
|
r = h * 0.4;
|
|
|
context.beginPath();
|
|
|
context.moveTo(l, t + h / 2);
|
|
|
context.lineTo(l + r, t);
|
|
|
context.lineTo(l + w - r, t);
|
|
|
context.arcTo(l + w, t, l + w, t + h, r);
|
|
|
context.arcTo(l + w, t + h, l, t + h, r);
|
|
|
context.lineTo(l + w - r, t + h);
|
|
|
context.lineTo(l + r, t + h);
|
|
|
context.lineTo(l, t + h / 2);
|
|
|
//context.arcTo(l, t + h, l, t, r);
|
|
|
//context.arcTo(l, t, l + w, t, r);
|
|
|
context.closePath();
|
|
|
context.fillStyle = bcolor;
|
|
|
context.fill();
|
|
|
context.stroke();
|
|
|
break;
|
|
|
}
|
|
|
case 8:{
|
|
|
//绘制连接框
|
|
|
//计算宽高
|
|
|
var l = x1, t = y1;
|
|
|
var w = x2 - x1, h = y2 - y1;
|
|
|
if (w < 0)
|
|
|
{
|
|
|
l = x2;
|
|
|
w = x1 - x2;
|
|
|
}
|
|
|
if (h < 0){
|
|
|
t = y2;
|
|
|
h = y1 - y2;
|
|
|
}
|
|
|
context.strokeStyle = color;
|
|
|
context.lineWidth = size;
|
|
|
context.beginPath();
|
|
|
context.arc(l + w / 2, t + h / 2, Math.min(w, h), 0, 360);
|
|
|
context.closePath();
|
|
|
context.fillStyle = bcolor;
|
|
|
context.fill();
|
|
|
context.stroke();
|
|
|
break;
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
|
|
|
//计算当前字体下的文本宽度
|
|
|
function getFontWidth(context, txt) {
|
|
|
const metrics = context.measureText(txt);
|
|
|
const actual = Math.abs(metrics.actualBoundingBoxLeft ?? 0) + Math.abs(metrics.actualBoundingBoxRight ?? 0);
|
|
|
const width = Math.max(metrics.width, actual);
|
|
|
return width;
|
|
|
}
|
|
|
//计算当前字体下的文本高度
|
|
|
function getFontHeight(context, txt) {
|
|
|
const metrics = context.measureText(txt);
|
|
|
const fontHeight = metrics.fontBoundingBoxAscent + metrics.fontBoundingBoxDescent;
|
|
|
//所有字在这个字体下的高度
|
|
|
//const actualHeight = metrics.actualBoundingBoxAscent + metrics.actualBoundingBoxDescent;
|
|
|
return fontHeight;
|
|
|
}
|
|
|
//自动调整字体大小
|
|
|
function updateFont(context, w, h, text, size){
|
|
|
context.font = size + "pt SimSun";
|
|
|
w1 = getFontWidth(context, text) * 2;
|
|
|
h1 = getFontHeight(context, text) * 2;
|
|
|
var s = size;
|
|
|
while (w1 > w || h1 > h){
|
|
|
s = s - 1;
|
|
|
context.font = s + "pt SimSun";
|
|
|
w1 = getFontWidth(context, text) * 2;
|
|
|
h1 = getFontHeight(context, text) * 2;
|
|
|
}
|
|
|
return s;
|
|
|
} |
