Google SketchUp: The Missing Manual

Using the Offset Tool

The world is full of symmetry—both natural and human made. This fact was not lost on SketchUp's software engineers; they created the handy Offset tool so you can easily copy and use the existing shapes and edges in your drawing. The Offset tool is in the toolbar, near the Move and Push/Pull tools, or you can choose Tools → Offset. For some tips and details about using the Offset tool, see the box on the next page. In this next exercise, you'll trim out the window and doors of your house model. Trim out is a carpenter's term for applying wood trim around something like a door or window. Trim hides the seams and provides a more finished look.

Figure 4-19. By using the Move (M) tool and an inference line, you can align elements like this garage door to other parts of your model, like the peak of the roof.

UP TO SPEED: Saving Time with the Offset Tool

The Offset tool does more than simply copy and paste. The Offset tool lets you copy, paste, and modify with incredible speed. Consider a common architectural detail like the wood trim around windows. Perhaps it's a simple 1 x 4-inch piece of wood. You draw a rectangle for the window that's exactly the right dimensions. Then you need another rectangle (or two) with slightly different dimensions. With the Offset tool, you can select the rectangle for the window opening, and then enter a value such as 4" in the Measurements toolbar, and voilà—you've created window trim. Need to create window trim for 6, 12, or 24 more windows? Just double-click the window openings. The Offset tool remembers your last operation and applies that preset value to any thing you double-click.

Go ahead and try it using an empty or unused area of a SketchUp document. Change to Top view, and then create a 3-inch circle. Zoom in to get a good view. Grab the Offset tool and move it toward the circle. When you get close, you see a red square jump to the edge of the circle. That's the magic of auto-selection—SketchUp is always trying to figure out what you're going to do next. Drag slightly away from the circle, type 3", and then press Enter. A new circle appears around the original circle. Double-click the outer edge of the circle a couple more times. Each time you do, SketchUp creates a new circle 3 inches away from the perimeter of the last circle. When you're done, you have a perfectly formed target symbol like the one shown in Figure 4-20. Just add color, and you're ready for archery practice.

For the purposes of learning SketchUp, the trim out process provides a great introduction to the Offset tool. Before you use the Offset tool, make sure nothing in your model is selected by pressing Ctrl+T (Shift-⌘-A).

Figure 4-20. This 2-D design that looks like a target was created by drawing a 3-inch circle and then repeatedly creating a new edge using the Offset tool.

1. Select the Offset tool and then move the cursor over different parts of your house model.

   As you move the cursor around your model, auto-selection kicks into action. Different faces are highlighted and a red square snaps to different edges. The square marks the target of the offset operation.

2. Click once while the red square is on the edge of the window.

   The square locks in place on the edge. Now as you move the cursor, you see another rectangle that indicates the shape to be created by the offset. Drag the cursor away from the opening to create an offset on the outside of the window opening, or drag it toward the center of the opening to create an offset inside. As you drag, the offset distance is displayed in the Measurements toolbar, as shown in Figure 4-21. If you want to be precise, you can type a value in the Measurements toolbar.

3. Move the cursor toward the middle of the window, and when you're happy with the size of the window trim, click once.

   A new rectangle appears within the original window opening.

   

   Figure 4-21. The red highlight marks the edge or edges being duplicated in the offset action. Here the inner rectangle shows where the new edges will appear. The Measurements toolbar gives you an idea of the dimensions of the offset.

4. Double-click the edge of the inner rectangle.

   The Offset tool creates another rectangle inside of the window with the same offset distance.

5. Use the Push/Pull tool to push back the "glass" at the center. Then push back the frame about half that distance. Finally, pull out the trim so that it's about an inch or two in front of the surface of the house.

   Adjust these features to taste for now. If you want, you can enter precise values in the Measurements toolbar.

Tip

When you're creating the trim and window frame details with the Push/Pull tool, it helps to change the camera view so you see the details from a slight angle. That makes it easier to judge the distance between the surfaces.

At this point the window trim looks pretty good. You've got an inset window frame and an outset window trim. For many buildings, the window and door trim are similar if not identical. When you look at the door, it's easy to see that it would look good with the same trim around the sides and top, but you don't really want trim on the bottom, where the door meets the floor. This calls for a little preselection before you apply the offset.

UP TO SPEED: More Offset Tool Tips

Once you begin thinking about it, you find many ways to use the Offset tool. For example, in the real world, walls have a specific thickness, whether in a house or in a garden. Using the Offset tool, you can speed up your wall construction. Here are some tips to remember when using the Offset tool:

• To offset all the edges of a single face, select the shape, and then click the edge with the Offset tool. Drag in either direction.

• You can't offset a single straight line or lines with complex connections—like a T or an X.

• You can offset lines with several straight or curved segments—like an M or an S.

• You can offset connected lines, but they must be coplanar. You can't offset lines that straddle a plane.

• To offset with precision, enter a value in the Measurements toolbar.

• If you only want to offset some but not all of the edges in a face, preselect the edges you want to use.

• To repeat the measurement of your last offset, just double-click your new target. It's much faster than entering a new dimension.

1. With the Select (space bar) tool, preselect both sides and the top of the door opening.

   Click one edge and then hold down the Ctrl (⌘ on a Mac) key. The arrow cursor displays a + sign to indicate that you can add elements to the selection. Click the other two edges to select them.

2. Change to the Offset (F) tool, and then click the top edge of the door.

   Because you preselected the edges of the door, the Offset tool automatically snaps to one of the three selected edges. Even if you hover over other parts of your drawing, it doesn't change the selection.

   When you click the top edge of the door, you see new offset lines for the three edges in the selection.

3. Move the cursor over to the inside corner of the window trim.

   With the selection locked in, you can move your cursor anywhere in the drawing window. In this case, you use the window trim as a reference to create the door trim.

4. When you see a tooltip that says "Endpoint" (as shown in Figure 4-22), click the corner.

   SketchUp creates an offset for the door trim that's similar to window trim. The three edges that were originally selected are still selected, making it easy to repeat the process to create the door frame.

   

   Figure 4-22. You can use inference locking with the Offset tool. Just hold the Shift key down, and then reference another point in your model. Here the dimensions of the window trim are used as a reference for creating the door trim.

5. Again click the door's top edge.

   The Offset tool goes into action, once again displaying new edges as you move the cursor.

6. This time, move the cursor to reference the inside edge of the window frame and then click.

   Another set of three lines appears, giving you an edge for the door frame.

7. Press P to select Push/Pull, and then click the door opening.

   After clicking, the face of the door moves back and forth as you move the cursor around the drawing area.

8. Click the window opening.

   When you click the window opening, Push/Pull uses that as a reference for the door and sets the door at the same depth in the wall.

9. Click the door frame, and then click the window frame.

   The door frame is the next section moving from the center to the outside of the door. You set its depth by referencing the window frame.

10. Click the door trim, and then click the window trim.

    The final clicks set the door trim so that it stands out from the wall the same distance as the window trim. Where you're done, your trimmed out door and window should look like Figure 4-23.

For consistency, you probably want to add trim to the opening for the garage door; however, it doesn't need an inset frame like the front door and window. You can trim out the garage door using the same technique you used for the front door. Preselect the two sides and the top edge, and then click the top with the Offset tool.

Figure 4-23. By using inferences along with the Offset and Push/Pull tools, you can quickly trim out your doors and windows.

Use the front door trim to size the trim for the garage door. You can use Push/Pull to set the garage door back in the wall, and then use it to pull the trim out from the wall surface.