Sketching

Sketching 1/7/10 2:45-3:30pm Supplement to "Creating a Topographic Subregion"

To create certain elements in Revit Architecture, such as roofs, floors, stairs, and railings, you draw them by sketching. Sketching is also required to define other types of geometry, such as extrusions, openings, and regions.

Topics

Sketching Terminology

• There are several terms specific to the sketching process in Revit Architecture:

  • Sketching is a process of drawing elements in Revit Architecture.
  • Sketch-based elements are those elements (for example, floors, ceilings, and extrusions) that are typically created using sketch mode. There are also elements, such as walls, that are sketched but do not require the use of sketch mode.
  • Sketch mode is an environment in Revit Architecture that allows you to sketch elements whose size or shape cannot be determined automatically, for example when you create (or edit a sketch of) a roof or a floor. When you enter sketch mode, the Ribbon only displays the tools applicable for the type of sketch you are creating or editing.
  • All the elements that comprise a sketch-based element (such as a roof) are known as the sketch.

    For example, a sketch-based roof is selected in the following image. (not shown)

    In this example, when you select the roof (created by extrusion), you can click Modify Roofs tab, Modify Roof panel, Edit Profile, which opens the sketch (the pink lines in the following image) in sketch mode. (For a roof created by footprint, select the roof and click Modify Roofs tab, Edit panel, Edit Footprint.) Here you can edit the individual elements of the sketch. The tools that are available in sketch mode vary depending on the type of element you are editing.

Sketching Elements

You can either draw sketch lines or use a Pick (Walls, Lines, Edges, Faces) option when sketching. Drawing allows you to create the element by clicking and moving the cursor; Pick options allow you to select existing walls, lines, edges or faces. As you sketch, you can use listening dimensions. For more information, see Listening Dimensions.

When you add elements whose size or shape cannot be determined automatically, such as a roof, extrusion, or opening, you enter sketch mode. In sketch mode, only the tools available for that sketch are available for use; the tools vary depending on the type of element you are sketching. There are also elements (such as walls) that are sketched but do not require the use of sketch mode.

Common Options for Sketches ( See Revit help "Sketching Elements" for table not shown)

Using Constraints When Sketching

You can use constraints while you are sketching by pressing Shift as you draw. Shift constraints works as follows:

• Constrains straight lines and radii of polygons to horizontal or vertical lines.
• Limits the chords of 3-point arcs, the radii of arcs from center and end points, and the axis of ellipses to multiples of 45 degrees.
• Limits 2-point and 3-point arcs to 90, 180, or 270 degrees.

Modifying Sketched Elements

In the drawing area, select a sketched element.

If you created the sketch for a sketch-based element, click the edit option to enter sketch mode.

For example, if you sketched a floor, click Modify Floors tabEdit panelEdit Boundary.

Modify the element:
move an entire element = select all of its sketch lines, and drag it to the desired location. If another element is attached, it updates accordingly.

modify the end of a sketch line = select it, and either drag the end control or edit the dimension. If you are moving the end control of a straight line segment, you can change the angle of the line or change the length of the line. If you move the end control of an arc, you change the number of degrees for the arc angle; if you drag the middle control, you change the radius.

If you were in sketch mode, when finished, click Finish .

Sketching and Work Planes

Each view in Revit Architecture is associated with a work plane. In some views (such as plan, 3D, and drafting) and for views in the Family Editor, the work plane is automatically set. In other views, such as elevation and section views, you need to set the work plane. The work plane is necessary for sketching operations such as creating an extruded roof, and for enabling tools in particular views, such as Rotate and Mirror in a 3D view.

When you set a work plane in a view, it is saved with that view. You can change the work plane as necessary.

When sketching, you can snap to the work plane grid, but you cannot align or dimension to it.

Additional Topics in this section

• Setting the Work Plane
• Making the Work Plane Visible
• Modifying Work Plane Grid Spacing
• Rotating a Work Plane Grid
• Elements Associated with Work Planes
• Creating a Work Plane-based Family

Creating Solid and Void Geometry

The tools you use to create solid and void geometry are available only in the Family Editor. For more information, see 'Family Editor' in the help menu.

For detailed information about creating families, including tutorials for creating geometry using the Family Editor, see 'The Families Guide' in the help menu.

Additional Topics in this section

• Creating an Extrusion
• Creating a Blend
• Creating a Revolve
• Creating a Sweep
• Creating a Swept Blend
• Cut Geometry
  
  

Creating 2D Geometry

To create 2D family geometry, you use the Revit Architecture Model and Symbolic lines tools that are available in the Family Editor.

The Model Line tool on the Create tabModel panel lets you sketch two-dimensional geometry for when you do not need to show solid geometry. For example, you could sketch door panels and hardware as 2D rather than sketch solid extrusions. Model lines are always visible in 3D views. You can control their visibility in plan and elevation views by selecting the lines and clicking Modify Lines tabVisibility panelVisibility Settings.

The Symbolic Line tool on the Detail tabDetail panel lets you sketch lines that are meant for symbolic purposes only. For example, you might sketch symbolic lines in an elevation view to represent a door swing. Symbolic lines are not part of the actual geometry of the family. Symbolic lines are visible parallel to the view in which you sketch them.

You can control symbolic line visibility on cut instances. Select the symbolic line and click Modify Lines tabVisibility panelVisibility Settings. Select Show only if instance is cut.

In the displayed dialog, you can also control the visibility of lines based on the detail level of the view. For example, if you select Coarse, that means that when you load the family into a project and place it in a view at the Coarse detail level, the symbolic lines are visible.

Adding a Reference Line

In the Family Editor, you can add a reference line in any view and use the same drawing tools and techniques used when adding model lines. When you sketch a reference line, it displays as a single line.

In a view where the model graphics are set to hidden line or wireframe, the sketched line displays as a solid line and the plane extents display with dashed lines.

To add a reference line

1. In the Family Editor, on the Create tabDatum panel, click Reference Line.
2. Using the drawing tools on the Options Bar, sketch the line.

   The line displays as a solitary solid line until selected or when highlighted during preselection.

   When selected or highlighted, the associated planes display according to the active view.

   To use reference lines and linear dimensions to control model geometry

   3. Align the face of a model element to the reference line and lock it.
   4. Add a dimension line referring to the reference line and label it as an instance or type parameter.
   5. Flex the model by changing and applying a new value within the Family Types dialog.