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html canvas-nest.js 源碼

存儲 png 進行 cti child 效果 nod rect 透明度

canvas-nest.js 這個js文件可以用來實現炫酷的線條與鼠標進行交互的功能,具體效果如圖所示

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js具體源碼如下:

/**
     * Copyright (c) 2016 hustcc
     * License: MIT
     * Version: %%GULP_INJECT_VERSION%%
     * GitHub: https://github.com/hustcc/canvas-nest.js
    **/
    ! function() {
      //封裝方法,壓縮之後減少文件大小
      function get_attribute(node, attr, default_value) {
        
return node.getAttribute(attr) || default_value; } //封裝方法,壓縮之後減少文件大小 function get_by_tagname(name) { return document.getElementsByTagName(name); } //獲取配置參數 function get_config_option() { var scripts = get_by_tagname("script"), script_len
= scripts.length, script = scripts[script_len - 1]; //當前加載的script return { l: script_len, //長度,用於生成id用 z: get_attribute(script, "zIndex", -1), //z-index o: get_attribute(script, "opacity", 0.5), //opacity c: get_attribute(script, "color", "0,0,0"), //color n: get_attribute(script, "count", 99) //count }; } //設置canvas的高寬 function set_canvas_size() { canvas_width = the_canvas.width = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth, canvas_height = the_canvas.height = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight; } //繪制過程 function draw_canvas() { context.clearRect(0, 0, canvas_width, canvas_height); //隨機的線條和當前位置聯合數組 var e, i, d, x_dist, y_dist, dist; //臨時節點 //遍歷處理每一個點 random_points.forEach(function(r, idx) { r.x += r.xa, r.y += r.ya, //移動 r.xa *= r.x > canvas_width || r.x < 0 ? -1 : 1, r.ya *= r.y > canvas_height || r.y < 0 ? -1 : 1, //碰到邊界,反向反彈 context.fillRect(r.x - 0.5, r.y - 0.5, 1, 1); //繪制一個寬高為1的點 //從下一個點開始 for (i = idx + 1; i < all_array.length; i++) { e = all_array[i]; // 當前點存在 if (null !== e.x && null !== e.y) { x_dist = r.x - e.x; //x軸距離 l y_dist = r.y - e.y; //y軸距離 n dist = x_dist * x_dist + y_dist * y_dist; //總距離, m dist < e.max && (e === current_point && dist >= e.max / 2 && (r.x -= 0.03 * x_dist, r.y -= 0.03 * y_dist), //靠近的時候加速 d = (e.max - dist) / e.max, context.beginPath(), context.lineWidth = d / 2, context.strokeStyle = "rgba(" + config.c + "," + (d + 0.2) + ")", context.moveTo(r.x, r.y), context.lineTo(e.x, e.y), context.stroke()); } } }), frame_func(draw_canvas); } //創建畫布,並添加到body中 var the_canvas = document.createElement("canvas"), //畫布 config = get_config_option(), //配置 canvas_id = "c_n" + config.l, //canvas id context = the_canvas.getContext("2d"), canvas_width, canvas_height, frame_func = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(func) { window.setTimeout(func, 1000 / 45); }, random = Math.random, current_point = { x: null, //當前鼠標x y: null, //當前鼠標y max: 20000 // 圈半徑的平方 }, all_array; the_canvas.id = canvas_id; the_canvas.style.cssText = "position:fixed;top:0;left:0;z-index:" + config.z + ";opacity:" + config.o; get_by_tagname("body")[0].appendChild(the_canvas); //初始化畫布大小 set_canvas_size(); window.onresize = set_canvas_size; //當時鼠標位置存儲,離開的時候,釋放當前位置信息 window.onmousemove = function(e) { e = e || window.event; current_point.x = e.clientX; current_point.y = e.clientY; }, window.onmouseout = function() { current_point.x = null; current_point.y = null; }; //隨機生成config.n條線位置信息 for (var random_points = [], i = 0; config.n > i; i++) { var x = random() * canvas_width, //隨機位置 y = random() * canvas_height, xa = 2 * random() - 1, //隨機運動方向 ya = 2 * random() - 1; // 隨機點 random_points.push({ x: x, y: y, xa: xa, ya: ya, max: 6000 //沾附距離 }); } all_array = random_points.concat([current_point]); //0.1秒後繪制 setTimeout(function() { draw_canvas(); }, 100); }();

在html網頁中body的標簽中添加script標簽,如下所示

<script type="text/javascript" color="208,55,66" opacity="0.5"count="99"src="test.js"></script>

color 顏色自定義,opactity 是透明度,一般來說0.5-1就可以了,count的是數量,不要太大,太大可能會使得用戶的瀏覽器卡頓,src後為該js文件的所在路徑。

PS:

我直接用test命令了那個js文件

html canvas-nest.js 源碼