Draw Commands

Even though most have the tools in the Draw drop down menu have already been discussed, we think that it worthwhile revisiting them in a module dedicated to their use. Here we will cover the use of the Line, Arc, Freehand, Circle and Polygon tools.

Draw drop down menu

SketchUp's Draw commands are grouped in a drop down menu (top). You can also activate and float a toolbar as shown in the figure below.

The line tool (command)

The line tool is the most basic of SketchUp commands. Select the tool, respond to the first prompt, indicate the x,y,z coordinate of the first point by clicking and then indicate the position of the end point of the line. You can draw on each of the three axes, or any point in between. Holding shift while you draw constrains a line to a face. The line is completed, the line tool stays operational, but to draw a new line from the end of the first line, you need to pick the endpoint again. This is foreign to AutoCAD and IntelliCAD users.

Select the end of the first line before drawing the second line.

Closing 4 lines creates a face.

The Line Tool is more powerful than first glance would suggest. You can use it to draw edges or line entities. Lines can be joined and if closed, form a face. Once a face has been created, you can use the Line Tool to divide faces or heal deleted faces.

Here the line tool has been used to draw on a face (from the mid point of one line to a point somewhere in the face and back to an edge) isolating a section which can be pulled up.

The Line Tool is activated either from the Drawing toolbar or the Draw menu.

Drawing lines on a face

Make sure that you know that SketchUp expects that you draw from edge to edge. Note the entity control points at key geometric positions (end point, mid point etc.) Green is end, red is edge and mid is cyan.

	Click here to play a movie which shows how a line can be drawn on the edge of a face to split the box in two. We also demonstrate how to avoid one of the common problems faced by users as they begin to use SketchUp.
	Click here to play a movie which puts another face (no pun intended) on the use of the line command. We concentrate on making sure that we draw in the red, green and blue axes and pay particular attention to the inference lines.

Combine some arcs and lines and use the Push/Pull tool as shown in the movie.

Lines and arcs being used in combination.

More on lines from the Help file

Keyboard Shortcut: L

Drawing a Line

Lines can be placed on existing faces or separate from existing geometry. To draw a Line:

1. Select the Line Tool. The cursor changes to a pencil.

2. Click to set the starting point of your line.

Note - Press the Esc key at any point during the operation to start over.

3. Move the cursor to the ending point of your line. As you draw a line, the length is displayed dynamically in the Value Control Box (VCB).

4. Click to draw your line. This ending point can also be the starting point of another line.

The line length can be specified precisely using the VCB either before clicking the second point or immediately after the line has been drawn. See Specifying Precise Line Values for further information on using the VCB with Line entities.

Tip - Alternately, you can click and hold the mouse button to set the starting point of the line, and drag outward without releasing the button to set the length. Release the mouse button to complete the line. See the Drawing panel of the Preferences dialog box for further information on setting drawing behavior.

Creating a Face

The Line Tool will remain at the ending point of every line you create. This end point is automatically treated as a starting point for another line. You can create another line by moving the cursor and clicking again from this new starting point. These two lines are said to be coplaner, intersecting lines (intersecting at starting and ending points).

Three or more coplanar lines, intersecting at their ending and starting points (forming a loop), generate a Face entity. Ensure that the Endpoint inference ToolTip is visible whenever you close a Face entity to ensure that any lines you draw are continuous. The Line Tool is released but is still active after a face has been created.

Tip - Set the display settings (Window > Display Settings ) to the Shaded rendering style to clearly show new faces as they are created.

Splitting a Face

Draw a line with starting and ending points on the face's edges to split a face. The following image shows a rectangle being split when a line is drawn from one edge of a face to another opposite edge.

Integrating Lines

Occasionally, overlapping lines will not be split or integrate with a face. Any lines that are not part of a face perimeter will be displayed with a thicker line (left-most image below) . The Profile Edge rendering style must be enabled in the Display Settings dialog box to see this behavior.  

Use the Line Tool to trace along an existing line to attempt to split overlapping lines. SketchUp will re-analyze your geometry and attempt to reintegrate the line. The following images show a bold line that did not effectively split a face (left-most image). The line was traced (middle-image) and the line became thin indicating that the line was reintegrated.  

Splitting a Line

SketchUp automatically splits line segments when new lines are drawn perpendicular to a line. For example, draw a new line to the midpoint (identified by a cyan square) of another line to split a line in half. The following example shows one line being intersected at the midpoint, resulting in two lines.

Select the original line to verify that the line has been split into two equal segments.

Dividing a Line into Equal Segments

Line segments can be divided into any number of equal line segments. To divide a line into equal segments:

1. Context-click on a line.

2. Select Divide from the context menu. SketchUp will place points on the line to show where the line will be divided.

3. Move the cursor toward the center of the line to reduce the number of segments. Move cursor toward either end of the line to increase the number of segments.

4. Click on the line when the number of segments you would like is shown. The line will be divided into an equal number of joined line segments.

Specifying Precise Line Values

The VCB displays the length of your line while you are drawing lines. You can also specify an line length value using the VCB.

Entering a Length Value

The VCB label indicates "Length" after you place the starting point of a line. The following image shows the length value in the VCB.

Type the length into the VCB, after placing the starting point of the line, and press the Enter or Return key. SketchUp will use the current document units setting if you only type in a numerical value. You can also specify either Imperial (1’6”) or Metric (3.652m) units at any time, regardless the model units setting.

Note - The Line Tool will snap to any previously entered length within the VCB.

Entering a 3D Coordinate

The VCB can also be used to place the end of the line at an exact coordinate in space.

Entering an Absolute Coordinate: Type in the coordinates of a point in 3D space enclosed by brackets, such as [x, y, z], to get absolute coordinates relative to the current axes.

Entering a Relative Coordinate:

Type the coordinate points enclosed by angle brackets, in the format <x, y, z>, where x, y, and z values are relative distances from the starting point of your line.

Note - The exact format for VCB entries will vary depending on your computer's Regional Settings. For European users, the list separator symbol may be a semi-colon instead of a comma, so the format would be
[x; y; z].

Drawing Lines by Inference

The Line Tool uses SketchUp's sophisticated geometric inference engine to help you place your lines in 3D space. The inference decisions, made by the inference engine, are displayed in the drawing area as inference lines and inference points. These lines and points show precise alignment between the line you are drawing and the geometry of your model. Refer to the inference engine topic for additional information.

Locking a Line to the Current Inference Direction

Press and hold the Shift key, while the line you are drawing is the specific color of an axis, to lock drawing operation to that axis.

Locking a Line to a Specific Inference Direction

Press and hold either the up arrow, left arrow, or right arrow keys, where the up arrow equals blue, left arrow equals green, right arrow equals red, while drawing a line to lock the line to a specific axis.

The arc command

The arc command is a little tricky to use and benefits from some practice.

SketchUp - the arc command

Use the rectangle tool. Select it and change its size by typing in the Value Control box (say 6000 for mm)

Use the arc tool, drawing from edge to edge then setting the bulge with the last click.

The arc command being used to fillet corners of a model.

The arc command (and shade sails)

It is sometimes easier to draw a triangle (or other planar surface) first before using the arc command.

Creating shade sails using the Arc tool.

SketchUp - shade sails with the arc command

Follow the instructions in the movie and draw a shade sail using the arc command.

Leave Google SketchUp running and return to your electronic notes.

Using the polygon tool (from the Help file)

Polygons can be placed on existing faces or separate from existing geometry. To draw a polygon:

1. Select the Polygon Tool. The cursor changes to a pencil with a polygon.

2. Click to place the center point of the polygon.

3. Move the cursor out from the center point to define the radius of your polygon. As you move the cursor, the radius value is displayed dynamically in the VCB and can be specified by typing in a length value followed by the Enter or Return key.

Note - Press the Esc key at any point during the operation to start over.

4. Click a second time to finish the polygon. (Alternately, you can click once to set the center of the polygon, and drag outward without releasing the button to set the radius. Release the mouse button to complete the polygon.)

Radius and segment values can be specified using the VCB immediately after a polygon is drawn.

Specifying Precise Polygon Values

The VCB displays the radius after setting the center point of a polygon. Use the VCB to enter an exact radius and number of segments.

Specifying a Radius

The VCB's label indicates "Radius" after you place the center point of the polygon. Type the radius size in the VCB, after placing the center point, and press the Enter or Return key. You can perform this action either during or immediately following the creation of the polygon. For example: 24r or 3'6"r or 5mr.

Specifying the Number of Sides

The VCB's label indicates "Sides" when the Polygon Tool is initially activated. Specify the number of sides in the VCB, and press the Enter or Return key, before clicking to set the center point of the polygon. For example: 10.

You can also specify the number of sides in a polygon immediately after the creation of the polygon. Type the number of sides in the VCB, followed by the letter 's', and press the Enter or Return key. For example: 6s. This number will be applied to any future polygons.

Locking a Polygon to its Current Orientation

Press and hold the Shift key, before you begin drawing a polygon, to lock drawing operation to that orientation.

More on Polygons

SketchUp's Polygon entities are similar to Faces entities, but can have 3 or more sides. These entities act as a single line in that they can define the edge of a face and also divide a face. Additionally, selecting one segment of the polygon selects the entire Polygon entity. However, all inference techniques will operate on the Polygon as though it were comprised of segments.

Note - You can explode a polygon into regular edge segments using the Explode Curve context menu item (see the Polygon Context Menu Items section later in this topic).

Polygon entities are comprised of a radius and number of segments. The following image shows a six-sided polygon.

Note - The model in the previous image contains two entities: a Face entity (in the middle) surrounded by a Polygon entity (the six-sided edge).

 Editing a Polygon Entity

You can edit the radius of a circle in which the polygon is inscribed, that does not yet bound a face, by using the Move Tool. To edit a Polygon entity:

1. Select the Move Tool. The cursor will change to a four-way arrow.

2. Move over the Polygon entity to locate the midpoint of a side. At least one midpoint of the polygon will allow you to resize the entity.

3. Click and hold on the midpoint of the Polygon entity.

4. Move the cursor to adjust the radius of the Polygon entity. Click and hold on another midpoint if the polygon does not resize. Try each midpoint until you find the midpoint that will resize the entity.

You can also adjust the radius and number of segments using the Polygon entity's  Entity Info dialog box.

Editing an Extruded Polygon

When you use the Push/Pull Tool to extrude a 2D face that includes a polygon, it extrudes a special polygonal curved face set which can also have its radius edited. Use the Move Tool to reposition one of the control edges, and the polygonal curved face set radius (as well as the radii of the two polygon entities that define it) will be adjusted accordingly.

Polygon Deformation

If a polygon is deformed in a way that destroys its radial definition, such as with a non-uniform scale operation, it will become a non-parametric Polyline Curve. Polyline Curves can no longer be edited as polygons.

Freehand

The Freehand tool draws curves on existing faces (or on axes). We find that this tool is very difficult to control and places rather too many entities into the drawing. We believe that flexible curves are best drawn as Bezier curves. The curve in the model below was drawn in CAD software (IntelliCAD) and then imported into the SketchUp environment.

Bezier curves are also a feature of Adobe's Illustrator program - a tool which also generates DXF files which can be imported to SketchUp.

This shape was imported into SketchUp as a DXF file.

To apply these in the SketchUp environment, it is necessary to load what is called a Ruby scrip. More on that in a later module.

To draw a curve:

1. Select the Freehand Tool. The cursor will change to a pencil with a curve.

2. Click and hold to place the starting point of your curve.

3. Drag the cursor to draw.

4. Release the mouse button to stop drawing.

Drawing a curved shape on a face with the Freehand tool.

Rectangle

Let's take another look at the rectangle tool.

Circle

We have already experimented enough with this tool.

That completes a further look at the various draw commands.

Review

Please review your knowledge of the material in this module before progressing to the next stage. When you have done this, return to the menu of modules.