Stretching Geometry拉伸几何体

When you move geometry that's connected to other geometry, SketchUp stretches your model.当您移动与其他几何体连接的几何体时，SketchUp会拉伸您的模型。

To stretch your geometry, select the Move tool () and click and drag any of the following:要拉伸几何体，请选择“移动”工具（），然后单击并拖动以下任意一项：

  • An edge
  • A face
  • A point

In the figure, you see a basic box (1) and copies of that box that were stretched by an edge (2), a face (3), and a point (4), respectively. If you want to stretch a surface entity (basically, any form with a curved edge) or bend a face (like Box 4 in the figure), special rules apply, which are covered in the following sections.在图中，您可以看到一个基本框（1）以及分别由边（2）、面（3）和点（4）拉伸的该框的副本。如果要拉伸曲面实体（基本上是任何具有弯曲边的形状）或弯曲面（如图中的框4），则适用特殊规则，这些规则将在以下部分中介绍。

Tip: If you want to stretch part of your model to a specific scale (for example, make a box twice as wide), see Scaling Your Model or Parts of Your Model.如果要将模型的一部分拉伸到特定比例（例如，将一个框的宽度扩大一倍），请参阅缩放模型或模型的部分。
Table of Contents目录
  1. Resizing surface entities调整曲面图元的大小
  2. Bending faces with Autofold带自动折叠功能的曲面

Resizing surface entities调整曲面图元的大小

In a surface entity, if you click and drag a control edge, you resize the surface entity without distorting the geometry. 在曲面图元中，如果单击并拖动控制边，则可以在不扭曲几何图形的情况下调整曲面图元的大小。You create a surface entity by extruding an arc, circle, or polygon; see Softening, Smoothing, and Hiding Geometry as well as articles about arcs, circles, and polygons for details.通过拉伸圆弧、圆或多边形来创建曲面图元；有关详细信息，请参阅软化、平滑和隐藏几何体以及关于圆弧、圆和多边形的文章。

When you position the Move tool over a surface entity's control edge, the edge lights up in a way that nearby edges do not. In the following figure, the Move tool has selected a control edge in the cylinder's surface entity, and you see how dragging that edge enlarges the cylinder.将“移动”工具放置在曲面图元的控制边上时，该边会以附近边不会的方式亮起。在下图中，“移动”工具在圆柱体的曲面实体中选择了一条控制边，您可以看到拖动该边是如何放大圆柱体的。

Tip: To make a surface entity look smooth, SketchUp by default hides surface entity edges. Viewing hidden edges can help you find the control edge easily. 为了使曲面图元看起来平滑，默认情况下SketchUp会隐藏曲面图元边。查看隐藏边可以帮助您轻松找到控制边。To see hidden geometry, select View > Hidden Geometry.要查看隐藏几何体，请选择“视图>隐藏几何体”。
Note: A surface entity extruded from a curve entity does not have a control edge. Similarly, if you stretch a circular cylinder into an ellipse, the surface entity also lacks a control edge.从曲线图元拉伸的曲面图元没有控制边。同样，如果将圆柱体拉伸成椭圆，则曲面图元也缺少控制边。

Bending faces with Autofold带自动折叠功能的曲面

In SketchUp, faces must remain planar. If you stretch geometry in a way that bends a face, Autofold makes a crease so that all the faces in your geometry remain flat. The following figure shows before-and-after examples of Autofold's handiwork.在SketchUp中，面必须保持平面。如果以弯曲面的方式拉伸几何体，则“自动折叠”会产生折痕，使几何体中的所有面保持平坦。下图显示了Autofold手工制作前后的示例。

Tip: Sometimes, SketchUp constrains an operation to keep all faces planar instead of creating additional fold lines. 有时，SketchUp会约束一个操作，使所有面保持平面，而不是创建额外的折叠线。If SketchUp isn't Autofolding when you want it to, tap the Alt key (Microsoft Windows) or Command key (macOS) key to toggle Autofold as you drag the geometry, allowing geometry to move freely in any direction.如果SketchUp在需要时没有自动折叠，请在拖动几何体时点击Alt键（Microsoft Windows）或Command键（macOS）切换自动折叠，允许几何体在任何方向上自由移动。