add show image

README.md

@@ -28,15 +28,17 @@ use `C-c w` shortcur key in "200px" chars, it will auto convert to
 }
 ```
 
+![show](px2vw.gif)
+
 ## 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`.
-2. Not support convert all px values at a time.
+
 
 ## Refer
 [李杀的Elisp学习笔记](https://emacsist.github.io/2018/01/03/%E6%9D%8E%E6%9D%80%E7%9A%84elisp%E5%AD%A6%E4%B9%A0%E7%AC%94%E8%AE%B0/)
-[Emacs Lisp](https://www.gnu.org/software/emacs/manual/html_node/elisp/)
+[Emacs Lisp](https://www.gnu.org/software/emacs/manual/html_node/elisp/)

px2vw.el

@@ -1,7 +1,9 @@
 ;;; px2vw.el --- convert px to vw in css
 ;;; Commentary:
 ;;; Code:
-
+
+(defvar viewpoint-width 1440.0)
+
 (defun region-px->vw (pos1 pos2)
   "当前选中region或者paragraph中的px转化为vw，可能还需要考虑:
    1. 1px的情况
@@ -18,10 +20,10 @@
       (let* ((px-digit-str (match-string 1))
              (px-digit (string-to-number px-digit-str))
              (vw-digit (format
-                        "%.2f"
+                        "%.4f"
                         (/
                          (* 100.0 px-digit)
-                         1440.0))))
+                         viewpoint-width))))
         (replace-match (concat vw-digit  "vw") t nil)))))
 
 ;;(global-set-key (kbd "C-c w") 'px->vw)