2012

Table Of Contents
such as electrical parts or dimensions. Also, you can lock a layer to prevent
objects on that layer from being accidentally selected and modified.
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 still hide objects
when you use HIDE. 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 may cause
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.
NOTE Instead of turning off or freezing a layer, you can fade the layer by locking
it. See Lock the Objects on a Layer below.
Control Transparency on Layers
Set the transparency of layers and layout viewports to enhance drawings by
reducing the visibility of all object on specific layers as needed. Set layer (or
layout viewport) transparency in the Layer Properties Manager.
After you apply transparency to a layer, all objects added to that layer are
created at the same level of trasparency. The transparency property for all
objects on the layer is set to ByLayer.
Assign a Default Color and Linetype to a Layer
Each layer has associated properties such as color, linetype, and transparency
that are assumed by all objects on that layer when the setting is ByLayer.
For example, if the Properties palette set to BYLAYER when no object is
selected, the color of new objects is determined by the color setting for the
layer in the Layer Properties Manager.
382 | Chapter 15 Control the Properties of Objects