Introduction

This is a emcas plugin to convert px unit to vw or vh in css or other files.

How to use

• Download the px2vw.el file to your emcas elisp configuration directory, generally it is ~/.emcas.d/lisp/ in MacOS. Or copy the content of px-2vw.el to a .el file in emcas el config path, and i suggest to also named px2vw.el.

• Add blow code to your emcas config file, ~/.emcas.d/init.el or ~/.emcas.d/custom.el are ok.

(require 'px2vw)
(global-set-key (kbd "C-c w") 'region-px->vw)

Now，you added a shortcut key to emacs, if it is inconvenient, you can set F9 to do this.

(global-set-key [f9] 'region-px->vw)

• Move point to width number with "px" unit, and press shortcut key C-c w, px unit will convert to vw. For example:

.div {
    width: 200px;
}

use C-c w shortcur key in "200px" chars, it will auto convert to

.div {
    width: 13.8889vw;
}

Explaintin

The vw value is convert by expression (/ (* px 100) viewport-width) and maintain four float points.

Remind

1. I gived default width of viewport is 1440, and not support to change by param, so if you want to change, please modify value of the first line constant viewpoint-width in px2vw.el.

Refer

李杀的Elisp学习笔记 Emacs Lisp