How to draw a roadmap using canvas (code)
The content of this article is about how to use canvas to draw a roadmap (code). It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=Edge">
<meta content="always" name="referrer">
<meta content="width=device-width, initial-scale=1.0, minimum-scale=1.0" name="viewport" />
<title>CITEK反向寻车</title>
<script src="<%=basePath%>wui/js/jquery.js"></script>
<link rel="stylesheet" href="<%=cssPath%>wui.css" type="text/css"></link>
<script type="text/javascript" src="<%=basePath%>wui/js/line_tool.js"></script>
<script type="text/javascript">
var arrPosX = [], arrPosY = [];
<s:iterator value="listNode" status="bean"> //设置路线中点的横坐标和纵坐标的集合
arrPosX.push(<s:property value="posX" />);
arrPosY.push(<s:property value="posY" />);
</s:iterator>
var arrRoundPosX = [], arrRoundPosY = []; //设置终点所在区域的范围点横坐标和纵坐标集合
<s:iterator value="positionsX" status="bean">
arrRoundPosX.push(<s:property />);
</s:iterator>
<s:iterator value="positionsY" status="bean">
arrRoundPosY.push(<s:property />);
</s:iterator>
var ctxBackground, canvasBackground;
var ctxSource, canvasSource;
var canvasWidth, canvasHeight;
var imgStart, imgEnd, imgBackground,;
var areaImage;
var isStart = false;
var scale = 1;
var scaleInterval = 3;
var scaleCount = 0;
var runCount = 0;
var step = 2; //像素
var moveX = 1;
var moveY = 1;
var currIndex = 0;
var a = 0;
var tmpIconPaths = [ //设置起点图标
"<%=basePath%>img/point_start.png",
];
var imgObjArr = [];
var iLoadIndex = 0;
/**
* 将图标放入集合中
*/
function loadIconImages(){
var oImg = new Image();
oImg.addEventListener('load', eventIconImagesLoaded, false);
oImg.src = tmpIconPaths[iLoadIndex];
imgObjArr.push(oImg);
}
/**
* 加载图标
*/
function eventIconImagesLoaded(){
iLoadIndex++;
if(iLoadIndex <= 3) {
loadIconImages();
} else {
loadImage();
}
}
/**
* 加载背景图标
*/
function loadImage(){
areaImage = new Image();
areaImage.addEventListener('load', eventAreaImageLoaded, false);
areaImage.src ="<%=basePath%>image/img.jpg;
}
function eventAreaImageLoaded(){
initBase();
initScene();
initSprits();
start();
isStart = true;
}
/**
* 初始化
*/
function initBase() {
imgStart = imgObjArr[0];
canvasBackground = document.getElementById("canvasBackground");
ctxBackground = canvasBackground.getContext("2d");
canvasSource = document.getElementById("canvasSource");
ctxSource = canvasSource.getContext("2d");
canvasWidth = areaImage.width;
canvasHeight = areaImage.height;
var bodyWidth = document.body.clientWidth-10;
var bodyHeight = document.body.clientHeight-10;
var tmpCavW = canvasWidth;
var tmpCavH = canvasHeight;
if(canvasWidth > bodyWidth) {
canvasWidth = bodyWidth;
canvasHeight = canvasWidth * (tmpCavH/tmpCavW);
}
if(canvasHeight > bodyHeight){
canvasHeight = bodyHeight;
canvasWidth = canvasHeight * (tmpCavW/tmpCavH);
}
canvasBackground.width = canvasWidth;
canvasBackground.height = canvasHeight;
canvasSource.width = canvasWidth;
canvasSource.height = canvasHeight;
moveX = arrPosX[0] * canvasWidth;
moveY = arrPosY[0] * canvasHeight;
}
/**
* 初始化画布
*/
function initScene() {
ctxBackground.drawImage(areaImage, 0, 0, canvasWidth, canvasHeight);
}
/**
* 开始绘图
*/
function initSprits() {
/* 绘制路线的白底 */
ctxBackground.beginPath();
ctxBackground.strokeStyle = "white";
ctxBackground.lineWidth = 8;
ctxBackground.lineCap = "round";
ctxBackground.lineJoin = "miter";
ctxBackground.miterLimit = 30;
for(var i=1; i < arrPosX.length; i++){
ctxBackground.moveTo(canvasWidth * arrPosX[i-1], canvasHeight * arrPosY[i-1]); //指定一条线段的起点
ctxBackground.lineTo(canvasWidth * arrPosX[i], canvasHeight * arrPosY[i]); //指定一条线段的终点
}
ctxBackground.stroke();
/* 绘制路线的红线 */
ctxBackground.beginPath(); //是通过覆盖白底实现的
ctxBackground.strokeStyle = "rgba(255,0,0,1)";
ctxBackground.lineWidth = 4;
ctxBackground.lineCap = "round";
ctxBackground.lineJoin = "miter";
ctxBackground.miterLimit = 30;
for(var i=1; i < arrPosX.length; i++){
ctxBackground.moveTo(canvasWidth * arrPosX[i-1], canvasHeight * arrPosY[i-1]); //指定一条线段的起点
ctxBackground.lineTo(canvasWidth * arrPosX[i], canvasHeight * arrPosY[i]); //指定一条线段的终点
}
ctxBackground.stroke();
/* 绘制终点区域 */
ctxSource.clearRect(0, 0, canvasWidth,canvasHeight);
ctxBackground.beginPath();
ctxBackground.strokeStyle = "rgba(255,0,0,1)"; //颜色
ctxBackground.lineWidth = 0.5;
ctxBackground.fillStyle = "rgba(255,0,0,0)"; //透明度
ctxBackground.moveTo(canvasWidth * arrRoundPosX[0], canvasHeight * arrRoundPosY[0]); //指定一条线段的起点
for(var i=1; i < arrRoundPosX.length; i++){
ctxBackground.lineTo(canvasWidth * arrRoundPosX[i], canvasHeight * arrRoundPosY[i]); //指定一条线段的终点
}
ctxBackground.lineTo(canvasWidth * arrRoundPosX[0], canvasHeight * arrRoundPosY[0]);
ctxBackground.closePath();
ctxBackground.fill();
ctxBackground.stroke();
/* 绘制起点图标 */
ctxBackground.drawImage(
imgStart,
canvasWidth * arrPosX[0] - imgStart.width * 0.25,
canvasHeight * arrPosY[0] - imgStart.height * 0.25 - imgStart.height * 0.25,
imgStart.width * 0.5,
imgStart.height * 0.5);
}
/**
* 设置图标的跳动
*/
function loop(){
if(!isStart) return;
if(scale > 1.8) scale = 1;
if(scaleCount > 999999) scaleCount = 0;
if(runCount > 999999) runCount = 0;
ctxSource.save();
ctxSource.clearRect(0,0,canvasWidth,canvasHeight);
/* 设置起点图标的跳动 */
ctxSource.translate(
canvasWidth * arrPosX[0] - imgStart.width * 0.25 +imgStart.width*0.25,
canvasHeight * arrPosY[0] - imgStart.height * 0.25+imgStart.height*0.25);
ctxSource.scale(scale, scale);
ctxSource.shadowOffsetX = 3; // 阴影x轴偏移
ctxSource.shadowOffsetY = 4; // 阴影y轴偏移
ctxSource.shadowBlur = 2; // 模糊尺寸
ctxSource.shadowColor = 'rgba(0, 0, 0, 0.5)'; // 颜色
ctxSource.drawImage(
imgStart,
- imgStart.width * 0.25,
- imgStart.height * 0.25 - imgStart.height * 0.25,
imgStart.width * 0.5,
imgStart.height * 0.5);
ctxSource.restore();
ctxSource.save();
/* 设置终点区域的透明度变化 */
if (runCount % 4 == 0) {
a = a + 0.1;
}
if (a > 0.6) {
a = 0;
}
ctxSource.strokeStyle = "rgba(255,0,0,1)";
ctxSource.lineWidth = 10;
ctxSource.fillStyle = "rgba(255,0,0,"+a+")";
ctxSource.moveTo(canvasWidth * arrRoundPosX[0], canvasHeight * arrRoundPosY[0]); //指定一条线段的起点
for(var i=1; i < arrRoundPosX.length; i++){
ctxSource.lineTo(canvasWidth * arrRoundPosX[i], canvasHeight * arrRoundPosY[i]); //指定一条线段的终点
}
ctxSource.lineTo(canvasWidth * arrRoundPosX[0], canvasHeight * arrRoundPosY[0]);
ctxSource.closePath();
ctxSource.fill();
ctxSource.restore();
ctxSource.save();
scaleCount++;
runCount++;
if(scaleCount % scaleInterval == 0){
scale += 0.1;
}
}
/**
* 设置标题和图片的长宽高和跳动频率
*/
function start(){
$("#monitor_list_box").width = canvasWidth + "px";
$("#monitor_list_box").height = canvasHeight + "px";
$("#canvasBackground").width = canvasWidth + "px";
$("#canvasBackground").height = canvasHeight + "px";
$("#canvasSource").width = canvasWidth + "px";
$("#canvasSource").height = canvasHeight + "px";
window.setInterval(loop,1000/30); //60帧
}
</script>
<style type="text/css">
#monitor_list_box {width:100%; height:auto; overflow: auto;}
#monitor_list_box canvas {position:absolute;width:100%; height:auto;}
</style>
<body>
<div id="monitor_list_box">
<canvas id="canvasBackground">
Your browser does not support the canvas element.
</canvas>
<canvas id="canvasSource">
Your browser does not support the canvas element.
</canvas>
</div>
</body>Related recommendations:
HTML5 Canvas - Examples of using paths to draw lines_html5 tutorial techniques
HTML5 drawing A simple and beautiful circuit diagram
Details introduction to the implementation case of HTML5 simple online drawing tool
The above is the detailed content of How to draw a roadmap using canvas (code). For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
How to run the h5 project
Apr 06, 2025 pm 12:21 PM
Running the H5 project requires the following steps: installing necessary tools such as web server, Node.js, development tools, etc. Build a development environment, create project folders, initialize projects, and write code. Start the development server and run the command using the command line. Preview the project in your browser and enter the development server URL. Publish projects, optimize code, deploy projects, and set up web server configuration.
What exactly does H5 page production mean?
Apr 06, 2025 am 07:18 AM
H5 page production refers to the creation of cross-platform compatible web pages using technologies such as HTML5, CSS3 and JavaScript. Its core lies in the browser's parsing code, rendering structure, style and interactive functions. Common technologies include animation effects, responsive design, and data interaction. To avoid errors, developers should be debugged; performance optimization and best practices include image format optimization, request reduction and code specifications, etc. to improve loading speed and code quality.
How to make h5 click icon
Apr 06, 2025 pm 12:15 PM
The steps to create an H5 click icon include: preparing a square source image in the image editing software. Add interactivity in the H5 editor and set the click event. Create a hotspot that covers the entire icon. Set the action of click events, such as jumping to the page or triggering animation. Export H5 documents as HTML, CSS, and JavaScript files. Deploy the exported files to a website or other platform.
What application scenarios are suitable for H5 page production
Apr 05, 2025 pm 11:36 PM
H5 (HTML5) is suitable for lightweight applications, such as marketing campaign pages, product display pages and corporate promotion micro-websites. Its advantages lie in cross-platformity and rich interactivity, but its limitations lie in complex interactions and animations, local resource access and offline capabilities.
What Does H5 Refer To? Exploring the Context
Apr 12, 2025 am 12:03 AM
H5referstoHTML5,apivotaltechnologyinwebdevelopment.1)HTML5introducesnewelementsandAPIsforrich,dynamicwebapplications.2)Itsupportsmultimediawithoutplugins,enhancinguserexperienceacrossdevices.3)SemanticelementsimprovecontentstructureandSEO.4)H5'srespo
Is H5 page production a front-end development?
Apr 05, 2025 pm 11:42 PM
Yes, H5 page production is an important implementation method for front-end development, involving core technologies such as HTML, CSS and JavaScript. Developers build dynamic and powerful H5 pages by cleverly combining these technologies, such as using the <canvas> tag to draw graphics or using JavaScript to control interaction behavior.
What is the H5 programming language?
Apr 03, 2025 am 12:16 AM
H5 is not a standalone programming language, but a collection of HTML5, CSS3 and JavaScript for building modern web applications. 1. HTML5 defines the web page structure and content, and provides new tags and APIs. 2. CSS3 controls style and layout, and introduces new features such as animation. 3. JavaScript implements dynamic interaction and enhances functions through DOM operations and asynchronous requests.
How to make pop-up windows with h5
Apr 06, 2025 pm 12:12 PM
H5 pop-up window creation steps: 1. Determine the triggering method (click, time, exit, scroll); 2. Design content (title, text, action button); 3. Set style (size, color, font, background); 4. Implement code (HTML, CSS, JavaScript); 5. Test and deployment.
