MFC鼠标中键拖动、同时滚轮缩放（根据鼠标位置）绘制的图形

[{"title":"（137个子文件60.34MB）MFC鼠标中键拖动、同时滚轮缩放（根据鼠标位置）绘制的图形","children":[{"title":"ScalePic.suo <span style='color:#111;'>14.50KB</span>","children":null,"spread":false},{"title":"ScalePic.sdf <span style='color:#111;'>55.83MB</span>","children":null,"spread":false},{"title":"stdafx.cpp <span style='color:#111;'>141B</span>","children":null,"spread":false},{"title":"ScalePic.vcxproj.filters <span style='color:#111;'>1.95KB</span>","children":null,"spread":false},{"title":"ScalePic.vcxproj.user <span style='color:#111;'>143B</span>","children":null,"spread":false},{"title":"......","children":null,"spread":false},{"title":" <span style='color:steelblue;'>文件过多，未全部展示</span>","children":null,"spread":false}],"spread":true}]