gulp-css-spriter 雪碧图合成

一、配置

gulp的雪碧图功能没有grunt那么强大，但是类似功能也支持，功能稍微弱一些，但是也很棒

npm地址：https://www.npmjs.com/package/gulp-css-spriter/ https://www.npmjs.com/package/grunt-css-sprite

vargulp=require('gulp'),
    minifyCSS=require('gulp-minify-css'),
    spriter=require('gulp-css-spriter');

二、gulp

gulp.task('css', function(){
    var timestamp = +new Date();
    return gulp.src(srcPath.css)
        .pipe(spriter({
            // 生成的spriter的位置
            'spriteSheet': './web/images/sprite_'+timestamp+'.png',
            // 生成样式文件图片引用地址的路径
            // 如下将生产：backgound:url(../images/sprite20324232.png)
            'pathToSpriteSheetFromCSS': '../images/sprite_'+timestamp+'.png'
        }))
        .pipe(minifyCss())
        .pipe(autoprefixer({
            browsers:['last 2 Chrome versions', 'Safari >0', 'Explorer >0', 'Edge >0', 'Opera >0', 'Firefox >=20'],
            cascade:false,
            remove:false,
        }))
        .pipe(gulp.dest(distPath.css));//保存压缩文件到指定的目录下面
});

三、css

.w{ 266px;height: 78px;background: url(../images/w.png?__spriter) 0 0 no-repeat;}
.j{ 270px;height: 60px;background: url(../images/jd.png?__spriter) 0 0 no-repeat;}
.t{ 290px;height: 100px;background: url(../images/tmall.png) 0 0 no-repeat;}

四、配置

gulp-css-spriter默认会对样式文件里，所有的background/background-image的图片合并，

但实际项目中，我们不是所有的图片都需要合并。

background-image:url(../slice/p1-3.png?__spriter);//有?__spriter后缀的合并

background-image:url(../slice/p-cao1.png);//不合并

修改下面文件可以按需合并。

node_modulesgulp-css-spriterlibmap-over-styles-and-transform-background-image-declarations.js

48行开始的if-else if代码块中， // background-image always has a url

 1         // background-image always has a url
 2         if(transformedDeclaration.property === 'background-image') {
 3             return cb(transformedDeclaration, declarationIndex, declarations);
 4         }
 5         // Background is a shorthand property so make sure `url()` is in there
 6         else if(transformedDeclaration.property === 'background') {
 7             var hasImageValue = spriterUtil.backgroundURLRegex.test(transformedDeclaration.value);
 8 
 9             if(hasImageValue) {
10                 return cb(transformedDeclaration, declarationIndex, declarations);
11             }
12         }

替换为下面代码：

 1                 //background-imagealwayshasaurl且判断url是否有?__bg 后缀
 2                 if(transformedDeclaration.property === 'background-image'&&/?__bg/i.test(transformedDeclaration.value)){
 3                     transformedDeclaration.value = transformedDeclaration.value.replace('?__bg','');
 4                     return cb(transformedDeclaration,declarationIndex,declarations);
 5                 }
 6                 //Backgroundisashorthandpropertysomakesure`url()`isinthere且判断url是否有?__bg 后缀
 7                 else if(transformedDeclaration.property === 'background'&&/?__bg/i.test(transformedDeclaration.value)){
 8                     transformedDeclaration.value = transformedDeclaration.value.replace('?__bg','');
 9                     var hasImageValue = spriterUtil.backgroundURLRegex.test(transformedDeclaration.value);
10                     if(hasImageValue){
11                         return cb(transformedDeclaration,declarationIndex,declarations);
12                     }
13                 }

完整图片

没有添加?__spriter不会合并

五、增强

function SpriterGroup(pathArr){
    for(let i = 0; i < pathArr.length; i++){
        gulp.src(pathArr[i]).pipe(spriter({
            'spriteSheet' : './dist/images/spriteSheet_' + i +'.png',
            'pathToSpriteSheetFormCss' : '../images/spriteSheet_' + i + '.png'
        })).pipe(gulp.dest('.dist/css'));)
    }
}
gulp.task('spirter', function(){
    spriterGroup([ 'a.css', 'b.css'])
})

var gulp = require('gulp');
var spriter = require('gulp-css-spriter');

gulp.task('css',function {
    return gulp.src('a.css').pipe(spriter({
        'spriteSheet' : './dist/images/spriteSheet_a.png',
        'pathToSpriteSheetFormCss' : '../images/spriteSheet_a.png'
    })).pipe(gulp.dest('.dist/css'));
});

gulp.task('css',function {
    return gulp.src('b.css').pipe(spriter({
        'spriteSheet' : './dist/images/spriteSheet_b.png',
        'pathToSpriteSheetFormCss' : '../images/spriteSheet_b.png'
    })).pipe(gulp.dest('.dist/css'));
});