govin-save-svg-as-png
v2.0.0
Published
Convert a browser SVG to PNG or dataUri
Downloads
7
Readme
saveSvgAsPng
Installation
npm install save-svg-as-png
Prerequisites
SaveSvgAsPng relies on JavaScript promises, so any browsers that don't natively support the standard Promise
object will need to have a polyfill.
Usage
To save a PNG, include the script saveSvgAsPng.js
in your page, then call the saveSvgAsPng
function with an SVG node and a filename:
saveSvgAsPng(document.getElementById("diagram"), "diagram.png");
The filename is the preferred filename when saving the image to the file system. The browser may change the name of the file if there is already a file by that name in the target directory.
If you want to scale the image up or down, you can pass a scale factor in an options object:
saveSvgAsPng(document.getElementById("diagram"), "diagram.png", {scale: 0.5});
Other options are documented below.
If you just want a dataURI for an SVG, you can call svgAsDataUri
, which returns a promise:
svgAsDataUri(document.getElementById("diagram"), options).then(uri => ...);
If you want a dataURI of a PNG generated from an SVG, you can call svgAsPngUri
, which also returns a promise:
svgAsPngUri(document.getElementById("diagram"), options).then(uri => ...);
Compatible with browserify and requirejs.
If you want to use TypeScript, necessary type definitions are available in Typings public registry.
Options
backgroundColor
— Creates a PNG with the given background color. Defaults to transparent.canvg
- If canvg is passed in, it will be used to write svg to canvas. This will allow support for Internet ExplorerencoderOptions
- A Number between 0 and 1 indicating image quality. The default is 0.8encoderType
- A DOMString indicating the image format. The default type is image/png.fonts
- A list of{text, url, format}
objects the specify what fonts to inline in the SVG. Omitting this option defaults to auto-detecting font rules.height
- Specify the image's height. Defaults to the viewbox's height if given, or the element's non-percentage height, or the element's bounding box's height, or the element's CSS height, or the computed style's height, or 0.left
- Specify the viewbox's left position. Defaults to 0.modifyCss
- A function that takes a CSS rule's selector and properties and returns a string of CSS. SupercedesselectorRemap
andmodifyStyle
. Useful for modifying properties only for certain CSS selectors.modifyStyle
- A function that takes a CSS rule's properties and returns a string of CSS. Useful for modifying properties before they're inlined into the SVG.scale
— Changes the resolution of the output PNG. Defaults to1
, the same dimensions as the source SVG.selectorRemap
— A function that takes a CSS selector and produces its replacement in the CSS that's inlined into the SVG. Useful if your SVG style selectors are scoped by ancestor elements in your HTML document.top
- Specify the viewbox's top position. Defaults to 0.width
- Specify the image's width. Defaults to the viewbox's width if given, or the element's non-percentage width, or the element's bounding box's width, or the element's CSS width, or the computed style's width, or 0.excludeUnusedCss
- Exclude CSS rules that don't match any elements in the SVG.excludeCss
- Exclude all CSS rules
Testing
run tests with tape
npm test
Support
Chrome limits data URIs to 2MB, so you may have trouble generating PNGs beyod a certain size.
Internet Explorer will only work if canvg is passed in, otherwise it will throw a SecurityError
when calling toDataURL
on a canvas that's been written to. canvg may have it's own issues with SVG support, so make sure to test the output.