Locking the aspect ratio plug-in can easily set the aspect ratio of SketchUp exported pictures. The parts that do not need to be exported will use a light black translucent mask to represent the safe frame range. When the aspect ratio is set to 0, the mask can be cancelled.
Fix Aspect Ratio（Fix Aspect Ratio）动画教程
Adjust the SketchUp window to the appropriate size, and lock it to the current aspect ratio after executing the command. You can also continue to reset the aspect ratio in the lower right input box or in the right-click menu.
锁定之后要怎么导出才是锁定的比例？