Copyright Goodheart-Willcox Co., Inc. Chapter 11 Subobject Editing 291 To scale a linear edge, enter the SCALE command. Select the edge using the [Ctrl] key. Pick a base point for the operation and enter a scale factor. You can also select the edge, pick the edge grip, and cycle to the SCALE mode. However, using the scale gizmo may be the best option. The direction of the scaled edge is related to the base point you select. The base point remains stationary, while the vertices in either direction are scaled. If you enter the SCALE command, you are prompted for the base point. If you select the edge grip, the grip becomes the base point. The differences in opposite end and midpoint scaling of an edge are shown in Figure 11-26. There are a few options to achieve different results when dynamically scaling an edge. The [Ctrl] key is used to access these options. First, select the edge. Then, pick the scale gizmo and press and release the [Ctrl] key to cycle through the options. If the [Ctrl] key is not pressed, the edge is scaled. The shape and planes of adjacent faces are changed to match the scaled edge. See Figure 11-27A. If the [Ctrl] key is pressed once, the edge is, in effect, not scaled. This is because the planes of adjacent faces are maintained. If the [Ctrl] key is pressed twice, the edge is scaled, as are edges attached to the modifi ed edge. However, if the scaling causes faces to become nonplanar, they may be triangulated. See Figure 11-27B. Edge retains its length Edge length changes Base point of rotation C A B Adjacent faces change Adjacent faces retain their planes Edge retains its length Triangular faces added Figure 11-25. Rotating an edge. A—The [Ctrl] key is not pressed. B—The [Ctrl] key is pressed once. Notice the top edge of the dark face. C—The [Ctrl] key is pressed twice.