From 12c6422b0e4a7e196c007f9582740d6094a0af70 Mon Sep 17 00:00:00 2001
From: "yaoyao.xie" <yaoyao.xie@yintech.cn>
Date: Fri, 30 Nov 2018 16:55:10 +0800
Subject: [PATCH] =?UTF-8?q?=E5=AE=8C=E5=96=84=E7=BB=98=E5=88=B6iamge?=
 =?UTF-8?q?=E7=9A=84aspectFill=E6=A8=A1=E5=BC=8F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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---
 lib/pen.js | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/lib/pen.js b/lib/pen.js
index 56c73c5..0d49efd 100644
--- a/lib/pen.js
+++ b/lib/pen.js
@@ -226,22 +226,20 @@ export default class Painter {
       height,
     } = this._preProcess(view);
     // 获得缩放到图片大小级别的裁减框
-    let rWidth;
-    let rHeight;
+    let rWidth = view.sWidth;
+    let rHeight = view.sHeight;
     let startX = 0;
     let startY = 0;
-    if (view.sHeight > view.sWidth) {
-      rHeight = Math.round((view.sWidth / width) * height);
-      rWidth = view.sWidth;
-    } else {
-      rWidth = Math.round((view.sHeight / height) * width);
-      rHeight = view.sHeight;
-    }
-    if (view.sWidth > rWidth) {
-      startX = Math.round((view.sWidth - rWidth) / 2);
-    }
-    if (view.sHeight > rHeight) {
+    // 绘画区域比例
+    const cp = width / height;
+    // 原图比例
+    const op = view.sWidth / view.sHeight;
+    if (cp >= op) {
+      rHeight = rWidth / cp;
       startY = Math.round((view.sHeight - rHeight) / 2);
+    } else {
+      rWidth = rHeight * cp;
+      startX = Math.round((view.sWidth - rWidth) / 2);
     }
     if (view.css && view.css.mode === 'scaleToFill') {
       this.ctx.drawImage(view.url, -(width / 2), -(height / 2), width, height);