Use Layers to Manage Complexity

You can use layers to control the visibility of objects and to assign properties to objects.

You can reduce the visual complexity of a drawing and improve display performance by controlling how objects are displayed or plotted. For example, you can use layers to control the properties and visibility of similar objects, such as electrical parts or dimensions.

Work with Layer States

Layer states include settings such as on or locked. If the drawing file contains named layer states, you can use them to change the way the drawing displays. If there are no layer states displayed in the Unsaved Layer State ribbon list, there are no layer states in the drawing.

Control the Visibility of Objects on a Layer

You can make drawing layers invisible either by turning them off or by freezing them. Turning off or freezing layers is useful if you need an unobstructed view when working in detail on a particular layer or set of layers or if you don't want to plot details such as reference lines. Whether you choose to freeze layers or turn them off depends on how you work and on the size of your drawing.

• On/Off . Objects on turned-off layers are invisible, but they can still hide other objects when they overlap. When you turn layers on and off, the drawing is not regenerated.
• Freeze/Thaw. Objects on frozen layers are invisible and do not hide other objects. In large drawings, freezing unneeded layers speeds up operations involving display and regeneration. Thawing one or more layers causes the drawing to be regenerated. Freezing and thawing layers takes more time than turning layers on and off.

In a layout, you can freeze layers in individual layout viewports.

Assign a Color and Linetype to a Layer

Each layer has associated properties such as color and linetype that are assumed by all objects on that layer. It is possible that some objects were assigned a property explicitly. For example, a layer named EXTERIOR WALLS might be assigned a default color of blue, but several exterior walls on the layer might be highlighted by setting the individual color property of those walls to red.

Note: In DWG TrueView, you can change only the default properties of a layer, but not properties that are set explicitly for selected objects in the original application.

Override Layer Properties in a Layout Viewport

Some layer properties can be changed using overrides on a viewport basis in layouts. Using layer property overrides is an efficient way to display objects using different property settings for color, linetype, lineweight, and plot style. Layer property overrides are applied to the current layout viewport.

For example, if you want objects on the Electrical layer to display prominently in one of two layout viewports, you set a Color override on the Electrical layer for each of the two viewports. By setting the color red for one viewport and gray for the other, you easily accomplish this objective without changing the global color property assigned to the layer.

Dim the Objects on a Layer (Locking Layers)

In the application that created the drawing, layers can be locked to prevent objects on that layer from being accidentally selected and modified, and are dimmed by default.

In AutoCAD, when a layer is locked, the objects on the layer are dimmed. This reduces the visual complexity of a drawing without turning off or freezing layers completely.

Note: Dimming objects on locked layers is available only in drawing files created with AutoCAD 2008-based products. The level of dimming is controlled by the product in which the drawing was last saved and cannot be changed in DWG TrueView.

Locked layers that are dimmed are plotted normally.

Procedures

To turn a layer on and off

1. Click Home tab Layers panel Layers Properties.
2. In the Layer Properties Manager, click the light bulb icon for the layer name that you want to turn on or off.

   If the light bulb is yellow, the layer is turned on.

To assign a color to a layer

1. Click Home tab Layers panel Layers Properties.
2. In the Layer Properties Manager, select a layer. Click the color icon.
3. In the Select Color dialog box, select a color.
4. Click OK to save and close.

To change the properties of more than one layer

1. Click Home tab Layers panel Layers Properties.
2. In the Layer Properties Manager list view, use one of the following methods to select the layers:
   • Hold down Ctrl and select the layer names.
   • Right-click. Click Show Filters in Layer List to display a check mark, and then select a layer filter.
3. Click the icons for the properties you want to change.
4. Click OK to save and close.

To move a column in the Layer Properties Manager

• Click on any column name and drag it to a new location.
• Right-click on any column name and click Customize. In the Customize Layer Columns dialog box, highlight the columns to move and click Move Up to move the columns to the left in the Layer Properties Manager. Click Move Down to move the columns to the right in the Layer Properties Manager.

Note: Column settings are specific to the drawing space in which they were set. For example, column settings applied in model space are not applied to the Layer Properties Manager when opened from paper space.

To hide a column in the Layer Properties Manager

Do one of the following

• Right-click on any column name. On the shortcut manager, select the column that is checked from the shortcut menu.
• Right-click on any column name and click Customize. In the Customize Layer Columns dialog box, deselect the columns that you want to hide.

Column names that are deselected in the shortcut menu are hidden. To show the column, right-click any column name and select the column name in the shortcut menu. The Name column cannot be hidden.

Note: Column settings are specific to the drawing space in which they were set. For example, column settings applied in model space are not applied to the Layer Properties Manager when opened from paper space.

To reset all columns to their default settings in the Layer Properties Manager

• Right-click on any column name and click Restore All Columns to Defaults.

All columns are reset to their original position, column width, and display status.

Note: Column settings are specific to the drawing space in which they were set. For example, column settings applied in model space are not applied to the Layer Properties Manager when opened from paper space.

To lock or unlock a layer

1. Click Home tab Layers panel Layers Properties.
2. In the Layer Properties Manager, click the padlock icon for the layer name that you want to lock or unlock.

   If the padlock is displayed open, the layer is unlocked.