告诉你们个秘密,把Vue和Canvas配对起来,网页效果超棒!让人惊讶,网页设计师岂能错过这个技巧。想做好网页设计,咱们得弄清楚Vue像个百宝箱,Canvas则是个HTML5的神奇画笔,用好了绝对牛逼!动手实践一下,感受这不一样的搭配乐趣!
Vue中的魔幻操作
亲们,让我们一起来瞅瞅vue.js如何搞定图片~这哥们儿可牛了,什么布局、图片,全都不在话下!但是使用前,你得先将图片传上网。别急,我给大家准备了一个超简单的vue小段子:
html
这个小窗可以帮你快速挑照片,选好就交给 handleImageChange 处理。之后,利用FileReader这个厉害货读取刚刚选中的图片文档,把它变成Base64编码,存到imageUrl这家伙里面。搞定后你就可以愉快地在网上看图咯!
Canvas中的魔法世界
Canvas能帮你搞图像,HTML5技能多得是。想课堂涂鸦吗?完全没问题,涂的效果还特细腻!像淡化图像这种高端技巧也能轻松搞定!
export default { data() { return { imageUrl: '', }; }, methods: { onFileChange(event) { const file = event.target.files[0]; const reader = new FileReader(); reader.onload = (e) => { this.imageUrl = e.target.result; }; reader.readAsDataURL(file); }, }, };
“`javascript
直接上网搜索”MyCanvas”画板,别忘了把名词换成”canvas“,就可以轻松定位!
咱们就用canvas的”2d”模式来画图,把ctx拿来。
const image = new Image();
image.src = imageUrl;
image.onload = function(){
export default { data() { return { canvasWidth: 500, canvasHeight: 400, }; }, mounted() { const canvas = this.$refs.canvas; const context = canvas.getContext('2d'); const imageUrl = 'https://example.com/image.jpg'; // 图像地址 const image = new Image(); image.onload = () => { context.drawImage(image, 0, 0, this.canvasWidth, this.canvasHeight); this.applyBlurEffect(context); // 应用模糊效果 }; image.src = imageUrl; }, methods: { applyBlurEffect(context) { const imageData = context.getImageData(0, 0, this.canvasWidth, this.canvasHeight); const data = imageData.data; for (let i = 0; i < data.length; i += 4) { const red = data[i]; const green = data[i + 1]; const blue = data[i + 2]; const alpha = data[i + 3]; // 简单的模糊算法,取上下左右四个像素的平均值 const blurRed = (data[i - 4] + data[i + 4] + data[i - this.canvasWidth * 4] + data[i + this.canvasWidth * 4]) / 4; const blurGreen = (data[i - 3] + data[i + 5] + data[i - this.canvasWidth * 4 + 1] + data[i + this.canvasWidth * 4 + 1]) / 4; const blurBlue = (data[i - 2] + data[i + 6] + data[i - this.canvasWidth * 4 + 2] + data[i + this.canvasWidth * 4 + 2]) / 4; data[i] = blurRed; data[i + 1] = blurGreen; data[i + 2] = blurBlue; } context.putImageData(imageData, 0, 0); }, }, };
ctx.drawImage(image,0,0);
让图片变模糊?太简单了!只需在代码输入这几句: blurEffect(ctx,0,0, canvas.width, canvas.height)搞定!
}
首先找出Canvas跟2D在哪儿,接着找张图片放进去。等到图片载入好了,就可以在Canvas上随心所欲地拖动drawImage了,最后给它加个模糊效果,搞定!
锐化效果大揭秘
我告诉你Canvas画磨砂效果很给力!锐利感也能轻松表现出来真的撒!
这个数列挺好玩的看出规律没?就是0,然后是-1,接着又是0,然后又来个-1,接着是5,然后又是-1,到头来还是0。就这样反反复复的,挺有意思~
const factor =1;
export default { data() { return { canvasWidth: 500, canvasHeight: 400, }; }, mounted() { const canvas = this.$refs.canvas; const context = canvas.getContext('2d'); const imageUrl = 'https://example.com/image.jpg'; // 图像地址 const image = new Image(); image.onload = () => { context.drawImage(image, 0, 0, this.canvasWidth, this.canvasHeight); this.applySharpenEffect(context); // 应用锐化效果 }; image.src = imageUrl; }, methods: { applySharpenEffect(context) { const imageData = context.getImageData(0, 0, this.canvasWidth, this.canvasHeight); const data = imageData.data; const weights = [ 0, -1, 0, -1, 5, -1, 0, -1, 0, ]; for (let i = 0; i < data.length; i += 4) { const red = data[i]; const green = data[i + 1]; const blue = data[i + 2]; const alpha = data[i + 3]; let blurRed = 0; let blurGreen = 0; let blurBlue = 0; for (let j = -1; j <= 1; j++) { for (let k = -1; k <= 1; k++) { const index = i + (j * this.canvasWidth * 4) + (k * 4); const weight = weights[(j + 1) * 3 + (k + 1)]; blurRed += data[index] * weight; blurGreen += data[index + 1] * weight; blurBlue += data[index + 2] * weight; } } data[i] = red + blurRed; data[i + 1] = green + blurGreen; data[i + 2] = blue + blurBlue; } context.putImageData(imageData, 0, 0); }, }, };
const bias =0;
搞定啦:就是把ctx和weights传给applySharpenEffect,再调整下其他设置就行了。
快来试这个3×3的锐化矩阵,给你的每一张照片加分,让它看起来更飒爽!最后看看你会得到怎样惊艳的结果!
这篇文章超级好懂,教你如何用Vue和Canvas做照片特效,例如让照片看起来更清晰或者变模糊等,都没问题!学会了这些,你就能处理各种高水平照片,制作出各种炫酷效果。不需要太多专业知识,按照步骤操作,肯定能轻松拿下!
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