Merge pull request #243 from jpc-ae/spritemap-documentation
SVG symbol sprite documentation & cleanup
diff --git a/README.md b/README.md
index ba796a3..1071e03 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
Material design icons are the official [icon set](http://www.google.com/design/spec/style/icons.html#icons-system-icons) from Google that are designed under the [material design guidelines](http://www.google.com/design/spec).
-## 2.1 Update
+### 2.1 Update
The 2.1 update adds 96 new icons!
@@ -12,9 +12,20 @@
Read the [developer guide](http://google.github.io/material-design-icons/) on how to use the material design icons in your project.
-## Using sprite sheets
+### Using a font collection
-In `css-sprite` and `svg-sprite` are pre-generated sprite sheets. Instructions for using them are in the [sprites documentation](https://github.com/google/material-design-icons/tree/master/sprites).
+The `iconfont` folder contains pre-generated font files that can be included in a project. This is especially convenient for the web; however, it is generally better to link to the web font hosted on Google Fonts:
+
+```html
+<link href="https://fonts.googleapis.com/icon?family=Material+Icons"
+ rel="stylesheet">
+```
+
+Read more in the [font portion](http://google.github.io/material-design-icons/#icon-font-for-the-web) of our full developer guide.
+
+### Using symbols and sprites
+
+The `css-sprite` and `svg-sprite` folders contain pre-generated sprite sheets, as well as svg symbols that can be `<use>`d more directly and with fewer constraints. Instructions for using them are in the [sprites documentation](https://github.com/google/material-design-icons/tree/master/sprites).
## Polymer icons
@@ -22,6 +33,6 @@
## License
-We have made these icons available for you to incorporate them into your products under the [Creative Common Attribution 4.0 International License (CC-BY 4.0)](http://creativecommons.org/licenses/by/4.0/). Feel free to remix and re-share these icons and documentation in your
-products. We'd love attribution in your app's *about* screen, but it's not required. The only thing we ask is that you not re-sell
-the icons themselves.
+We have made these icons available for you to incorporate them into your products under the [Creative Common Attribution 4.0 International License (CC-BY 4.0)](http://creativecommons.org/licenses/by/4.0/). Feel free to remix and re-share these icons and documentation in your products.
+We'd love attribution in your app's *about* screen, but it's not required.
+The only thing we ask is that you not re-sell the icons themselves.
diff --git a/iconfont/README.md b/iconfont/README.md
index 24fe46d..ce4141e 100644
--- a/iconfont/README.md
+++ b/iconfont/README.md
@@ -1,11 +1,9 @@
-The recommended way to use the Material Icons font is hosted by Google Fonts,
-available here:
+The recommended way to use the Material Icons font is by linking to the web font hosted on Google Fonts:
-```
+```html
<link href="https://fonts.googleapis.com/icon?family=Material+Icons"
rel="stylesheet">
```
Read more in our full usage guide:
http://google.github.io/material-design-icons/#icon-font-for-the-web
-
diff --git a/sprites/README.md b/sprites/README.md
index 8ad3fc93..f6ae102 100644
--- a/sprites/README.md
+++ b/sprites/README.md
@@ -1,71 +1,147 @@
# Material icon sprites
-These sprites may not be completely up-to-date, we will update them soon.
+Sprite images allow you to use images more efficiently.
+Our recommended way to use sprites is to create a single SVG file with the subset of icons needed for the project compiled as symbols.
+This will keep the file small and allow for the greatest flexibility in referencing each icon.
+It will also allow you to include any other svgs in the project, like a logo, in a single reference file.
+
+Note that symbol files must be `<use>`ed or opened in an editor in order to be viewed, while sprite sheets can be opened and previewed directly.
## Creating your own sprites
-Our recommended way to use sprite sheets is to create them with the subset of icons needed for the project. Here are two good options for creating your own CSS and SVG sprites.
+While PNG and SVG icon images can be combined manually in an editor, using a processor to combine them automatically and generate any needed companion files is definitely the most convenient.
+Here are three good options for creating your own CSS and SVG sprites.
- * [Sprity](https://www.npmjs.com/package/sprity) (previously css-sprite) for CSS sprites.
- * [svg-sprite](https://github.com/jkphl/svg-sprite) for SVG sprites.
+ * [Sprity](https://www.npmjs.com/package/sprity) (previously css-sprite) for PNG sprites with CSS sprite sheets.
+ * [svg-sprite](https://www.npmjs.com/package/svg-sprite) for SVG sprites with CSS sprite sheets.
+ * [svgstore](https://github.com/w0rm/gulp-svgstore) for SVG symbol sprites.
+
+When creating a project, there are many similar and extended processors that can be for compilers such as gulp.
+
+## Using the provided sprites
+
+Material design icons come with CSS sprite sheets and SVG symbol sprites for each category of icon we include.
+The icon sprites can be found in the `sprites` directory under `css-sprite` for png image sprites and `svg-sprite` for the various svg sprite techniques—including symbols.
+Symbol sprites in the `svg-sprite` folder have an additional `-symbol` marker after their name.
+If you are considering using svg sprites, you are encouraged to `<use>` the symbol sprites rather than traditional sprite sheets as they reduce the size of the files and the complexity and redundancy of using them.
-## Using provided sprite sheets
+## Using SVG symbol sprites
-Material design icons come with SVG and CSS sprites for each category of icon we include. These can be found in the `sprites` directory, under `svg-sprite` and `css-sprite`.
+To add an icon using symbol sprites, you will need to add an svg element that `<use>`es the reference file with a link to the specific icon you want.
+Since the icons are stored as `<symbol>`s, the viewbox is already set up and can be scaled relatively without needing to keep adjacent symbols in mind. You will only need set the size of the icon using CSS:
-### Using CSS Sprites
+```CSS
+.svg-24px {
+ width: 24px;
+ height: 24px;
+}
+```
-To use a CSS spritesheet, reference the stylesheet for the icon category you wish to use, then include the icon definition in your markup. E.g to use one of the play icons in `css-sprite-av`:
+Then reference the id for the icon you need:
+
+```HTML
+<svg class="svg-24px">
+ <use xlink:href="MaterialIcons.svg#ic_face_24px"></use>
+</svg>
+```
+
+The HTML can also be simplified further by targeting all svg tags, and then overriding the size for individual classes and IDs.
+While you will need to be careful not to let this hamper your layout, this kind of sizing is generally a matter of course.
+To make 24px the default for `<svg>` tags, add the tag properties in css:
+
+```CSS
+svg {
+ width: 24px;
+ height: 24px;
+}
+```
+
+Then reference the icon:
+
+```HTML
+<svg><use xlink:href="MaterialIcons.svg#ic_face_24px"></use></svg>
+```
+
+### Stacking symbol sprite icons
+
+Using symbol sprites, icons can also easily be stacked on top of each other by including them in a single svg `<use>` statement.
+Each icon can then be referenced using ids and classes and likewise handled using javascript.
+E.g. To add a blue checkmark on top of a checkbox outline than can then be hidden when needed, first add the fill property in CSS:
+
+```CSS
+.svg-24px {
+ width: 24px;
+ height: 24px;
+}
+.check {
+ fill: blue;
+}
+```
+
+Then add the check after the outline icon together with an id for the SVG tag (for targeting) and the check class for the checkmark:
+
+```HTML
+<svg class="svg-24px" id="checkbox-1">
+ <use xlink:href="MaterialIcons.svg#ic_check_box_outline_blank"></use>
+ <use class="check" xlink:href="MaterialIcons.svg#ic_check_box"></use>
+</svg>
+
+```
+
+### External SVG symbols
+
+The benefits to referencing an external svg come in the form of caching, as the same map file can be reused across the site and on subsequent visits.
+
+Unfortunately, Internet Explorer, Edge, and older Android and iOS browsers cannot `<use>` external svg files.
+Besides copying the svg file contents directly into each html file you need them in, there are two good ways to handle this:
+
+ 1. Use the [svg4everybody polyfill](https://github.com/jonathantneal/svg4everybody) (this is the preferred method)
+ 2. Use a simple AJAX call to include the symbol sprites in the document for all browsers, and then reference the svg directly wherever it is `<use>´d rather than the external file
+
+### CSS Selectors, Transformation and the Shadow DOM
+
+For some projects, parts of individual icons may be required to change or animate in some way relative to the icon, rather than as a whole. For example, an icon where the top part flies away or two parts are given separate colors. This is the power given to inline svg, as opposed to a simple image file.
+
+Browser support for the `<use>` element, however, is still not good enough to properly allow the targeting of its shadow DOM. While not impossible, it can make selecting individual paths on a page very tricky.
+
+In projects where individual paths need to be targeted, it is best to copy them inline or inject the paths into the html at build or load time, regardless of browser, to prevent issues that may arise due to the shadow DOM nature of the `<use>` element. There are two ways to handle this depending on the project:
+ 1. The recommended way to do this is automatically using a build script or with a tool like [gulp-inject](https://github.com/klei/gulp-inject) that can reference individual icons, as that will keep the html files small and prevent having to make an href request.
+ 2. If the project is designed to generate all pages dynamically using very few static elements, or none at all, the svg elements can instead be pulled in using javascript ajax calls. In this case, a purely concatenated xml file containing the individual icons required would work better and be easier to target than a symbol map.
+
+## Using CSS sprite sheets
+
+To use a CSS sprite sheet, reference the stylesheet for the icon category you wish to use, then include the icon definition in your markup.
+E.g. using one of the play icons in `css-sprite-av`...
Reference the stylesheet:
```html
- <link href="css-sprite/sprite-av-black.css" rel="stylesheet">
+<link href="png/sprite-av-black.css" rel="stylesheet">
```
-Create an element which will use the icon as a background:
+Create an element which will use the icon as a background, and include that icon as a class.
+The example class here references the `icon` sprite sheet and specific `icon-ic_play_circle_outline_black_24dp` icon, which you can get from the above stylesheet.
```html
- <div></div>
+<div class="icon icon-ic_play_circle_outline_black_24dp"></div>
```
-Add a class referencing the `icon` sprite sheet and specific icon `icon-ic_play_circle_outline_black_24dp`, which you can get from the above stylesheet.
+That's it! Well, for PNG sprites anyway.
+
+If you are using svg sprites by referencing `svg/sprite-av-black.css` in this example instead, you will also need to set a dimension for the icon.
+This can either be done inline or via a generic size class or a specific class such as this one:
```html
- <div class="icon icon-ic_play_circle_outline_black_24dp"></div>
+<style>
+ .svg-ic_play_circle_outline_black_24dp-dims { width: 24px; height: 24px; }
+</style>
```
-That's it!
-
-Don't forget to publish the corresponding CSS and SVG/PNG files when deploying your project.
-
-### Using SVG Sprites
-
-Similarly, to use an SVG sprite sheet, reference the stylesheet for the icon category, then include the icon definition in your markup.
-
-E.g: to use one of the play icons in `svg-sprite-av`, reference the stylesheet:
+Then, make sure you set the dimension for the specific icon, `svg-ic_play_circle_outline_black_24dp`, which you can get from the svg stylesheet.
```html
- <link href="svg-sprite/svg-sprite-av.css" rel="stylesheet">
+<div class="svg-ic_play_circle_outline_black_24dp svg-ic_play_circle_outline_black_24dp-dims"></div>
```
-Create an element which will use the icon as a background:
-
-```html
- <div></div>
-```
-
-Next, make sure to set a dimension for the icon. This can either be done inline or via a class. We'll use a class for this example:
-
-```html
- <style>
- .svg-ic_play_circle_outline_24px-dims { width: 24px; height: 24px; }
- </style>
-```
-
-Finally, set the dimension and specific icon `svg-ic_play_circle_outline_24px`, which you can get from the above stylesheet.
-
-```html
- <div class="svg-ic_play_circle_outline_24px svg-ic_play_circle_outline_24px-dims"></div>
-```
+Don't forget to publish the corresponding CSS and SVG/PNG files when deploying your project.
\ No newline at end of file
