Wednesday, February 10, 2010

7.1 Select Tool

Precise selection of objects is one of the most important skills for using Google Sketchup. If you cannot select objects accurately, you could end up doing bad things to your scene, such as moving objects that you didn't want to move. Fortunately, SketchUp 7 has a number of ways for you to select the objects you want and not select the objects you don't want to be included. The purpose of this tutorial is to show the different ways you can select objects easily.

So let's start SketchUp 7, with the Simple - Feet and Inches template. Turn on the Instructor by checking the Insstructor item from the Window menu. The Instructor tells us that the Select tool, the one with the arrow icon, is active. By the way, any time you want to get back to the Select tool, if another tool is active, press the space bar. This is a handy to get out of a situation where, for example, you're creating more rectangles than you want.

When the Select tool is active, and you only want to select one item, you can left click on it. A solid blue rectangular outline shows the bounds of the object you have selected. Once an object has been selected, you can use another tool to do something to the object. For example, click on the Move tool, the one with the 4 red arrows, and drag Sang, our default Sketchup person, to move him. Press Enter to complete the move. When you press the Space bar, the Select tool is active again. Sang is still selected.

Suppose you want to deselect Sang. To do that, there are one of two ways to do it. From the Edit menu, choose Select None. Left click on Sang to select him again. This time press Control-T, the shortcut for Select None. Sang is deselected.

Let's add some more objects to the scene, to see how we select and deselect multiple objects. Sketchup 7 has a built in library of components, pre-built objects, that we can add. From the Window Menu, select Components. Click on Components Sampler. Let's add a bench and a picnic table to keep Sang company. Find the component, then click and drag onto the scene.

With the Select tool active, click on Sang. If we click on the bench, we select the bench. If we click on the picnic table, we just select it. What if we want to select both Sang and the picnic table? To do that, before selecting Sang, hold down the control key. The arrow icon changes to an arrow with the plus sign, meaning that we're adding to the selection. Click on Sang. Now both Sang and the picnic table are selected. Similarly, clicking on the control key while clicking on the bench adds the bench to the selection. We can move all of them at once by clicking on the Move tool, dragging the cursor, and pressing Enter. Press the Space bar to make the Select tool active.

OK, we can move all three. What if we don't want to move the picnic table, but only move Sang and the bench? To do that, instead of holding down just the Control key, hold down the Shift key and the Control key together. The icon now has a minus sign, indicating that the object will be removed from the selection. Then click on the picnic table to remove it from the selection. Now click on the Move tool and drag with the mouse. Only Sang and the bench move.

One gotcha. If you click with the Shift key too often, you end up editing a component. A component is composed of a number of objects associated together. If this happens, click outside the component and then nothing will be selected, but at least you won't be editing a component.

A good shortcut. To select all objects in the scene, press Control-A. If you want to deselect all objects, press Control-T,

Another way to select multiple objects is to use a selection box. A selection box is a rectangle that selects objects either totally within the rectangle, or partially within the rectangle. The difference depends on whether you started the clicking on the right side or on the left side.

If you start the rectangle from the right side, you will select all objects that are within it, even partially. Even though the bench and the picnic table aren't totally within the selection rectangle, they are selected because we started the selection box from the right. This type of selection is called a Crossing Selection, because any object that the rectangle crosses will be selected. Press Control-A to deselect everything.

However, if you start the rectangle from the left side, you will only select Sang, because only he is totally inside the selection rectangle. This type of selection is called a Window Selection. This is a handy way to control precisely what objects you want to be selected.

Suppose you always want to do the same thing to a group of objects. Here's a quick tip that will save you the effort of reselecting. Suppose we want to move only Sang and the bench. Select Sang and the bench. From the Edit menu, select Create Group. Now you select both objects as a unit. Click on the Move tool to move them together. Press Enter to confirm. Then press Space bar to make the Select tool active. If you want to make Sang and the bench individual objects, from the Edit menu, select Group, then Explode. Now Sang and the bench can be selected individually, as before.

To demonstrate yet another way to select, based on an object's geometry, we'll create a rectangular solid. First press Control-A to select all the objects in the scene. Press the delete key to make them all disappear. Choose the Rectangle tool. Create a rectangle by clicking in the scene, dragging the mouse diagonally, and clicking again. Select the Push/Pull tool while the top face is selected. Now we have a rectangular solid.

There are a number of options for selecting edges and faces. To start, select the front face. The front face is selected because it is grey with black dots. Right click and choose Select. Choose Bounding Edges. This selects, in addition to the face, the 4 edges around it. Right click again. Choose Select. This time, choose Connected Facees. This doesn't choose the entire cube, only the faces that are connected to that face. Select the Orbit tool to orbit around. The back face of the rectangular solid is not selected. Now press the Space bar. Select a face. Right click. Choose Select. Choose All Connected. This time the entire cube is selected, all the edges and faces.

Here's an interesting short cut using the mouse. Select a face. Double click. This selects the face and its bounding edges. Triple click. This selects All Connected.

You can also select an edge, with a slightly different result. Press Control-T to deselect all. Then select an edge. Double click. This time, the two faces connected to the edge are selected. If you right click and select Connected Faces, you get the same result. This is the mirror image of when you select a face and get the bounding edges selected.

That's it! I hope you enjoyed this tour of SketchUp 7 Selection tools. Unless you're a veteran SketchUp user, I bet you learned something you didn't know before. If you liked my video, subscribe to my Youtube channel so you won't miss any more. Also, you can discuss this video at

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