隐藏背面

在隐藏面部背面的“扩展”菜单下添加一个开关——这也称为“背面剔除”。当您围绕场景旋转/平移时，面孔将不断更新。这对于处理内部空间或预览模型在渲染单边多边形的游戏引擎中的显示方式特别有用。您可以反转面（通过右键单击并选择“反转面”）来翻转哪一侧被认为是“正面”。

隐藏背面仅适用于未标记的面（也称为“第 0 层”），不适用于组或组件，除非您对其进行编辑。选定的面孔也将保持可见。

该扩展通过将所有隐藏的面孔移动到一个单独的隐藏标签来工作。只有当您移动相机或更改选择时，面孔才会更新。他们在使用其他工具时可能会不同步；只需稍微移动相机即可更新。

你可以使用etchup 的快捷方式首选项将快捷方式附加到菜单项。我推荐“Shift-K”，它反映了“K”快捷方式，用于查看后边缘。您可能还会发现将快捷方式附加到“反转面孔”很有用。

＃＃＃ 已知的问题
这些是 Ruby 扩展限制的结果。
– 如果在启用隐藏背面时撤消命令，它将暂时暂停以避免清除重做命令。当您进行任何其他更改时，它会自动恢复。
– 全选和框选将只选择可见的面孔。 （三次单击将选择所有连接的面，甚至是隐藏的。）
– 单个对象中有大量面孔时可能会很慢
作者：Jacob van’t Hoog
Adds a toggle under the Extensions menu which hides the back sides of faces — this is also known as “back-face culling.” As you orbit/pan around the scene, faces will be continuously updated. This is especially useful for working with interior spaces, or previewing how a model will appear in game engines that render single-sided polygons. You can reverse faces (by right clicking and choosing “Reverse Faces”) to flip which side is considered “front.”

Hide Back Faces only applies to untagged faces (aka “Layer 0”), and doesn’t apply to groups or components unless you edit them. Selected faces will also be kept visible.

The extension works by moving all hidden faces to a separate, hidden tag. The faces are only updated when you move the camera or change selection. They may get out of sync while using other tools; just move the camera slightly to update.

You can use Sketchup’s shortcut preferences to attach a shortcut to the menu item. I recommend “Shift-K,” which mirrors the “K” shortcut for viewing Back Edges. You may also find it useful to attach a shortcut to “Reverse Faces.”

### Known issues
These are a result of the limitations of Ruby extensions.
– If you undo a command while Hide Back Faces is enabled, it will temporarily pause to avoid clearing Redo commands. It resumes automatically when you make any other change.
– Select All and box-select will only select visible faces. (Triple-clicking will select all connected faces, even hidden.)
– It can be slow with large numbers of faces in a single object