11 Layers
Layers are a useful concept for organizing drawings. It's worth
learning how to work with layers - it will save you a lot of time especially
when drafting more complex constructions. This chapter will introduce you
into the concepts of layering and show you how QCad lets you manage the
layers of your drawing.
Every drawing contains at least one layer: layer '0'. Additional layers
can be created by the user at any time they are required. However, it's
recommended to plan a drawing and to create all necessary layers with the
correct attributes before starting to draft. The number of layers for a QCad
drawing is not limited. Every entity of your drawing is placed on exactly one
layer and a layer can contain an unlimited number of entities.
A Layer can be frozen to make all entities on it invisible. This way it
is easily possible to temporarily hide all dimensions, texts or auxiliary
constructions for a print out or to get a clearer overview of a complex
drawing.
The current layer is the layer you are working on. It is highlighted in
the layer list (Figure 14). Newly created entities are placed on
the current layer.
Layers can be controlled from the layer menu or in the layer list which
is usually shown at the right in the QCad application window (see Figure
14).

Figure 14: Layer list.
In Figure 14 the current layer is "construction". The eye
icon at the left side of each layer name indicates whether the layer is
currently visible or invisible (frozen). In this example, layer "auxiliary"
is frozen, the others are visible.
Changing the Visibility of a Layer
The visibility of a layer can be changed by either double-clicking on it
or by right-clicking on it and choosing "Toggle Visibility" from the context
menu (Figure 15).

Figure 15: Context menu of
the layer list.
Changing the Visibility of all Layers
Toolbar:

Menu:
Layer - Defreeze All
Layer - Freeze All
Hotkey:
th*, fr*
The two buttons shown above can be used to defreeze (thaw) or freeze all
layers at once, which comes in handy when working with a drawing that has
many layers. The same function is also available from the context
menu.
Adding New Layers
Toolbar:

Menu:
Layer - Add Layer
This command creates a new layer. The layer dialog is shown where you
can specify the name for the new layer and adjust its attributes (Figure
16).

Figure 16: Dialog for
creating new layers.
Deleting Layers
Toolbar:

Menu:
Layer - Remove Layer
You can delete the current layer with this command. Please note that
all entities on that layer will be deleted as well. This command, unlike most
other commands, can't be undone. However, if entities have been deleted with
the layer, they will reappear on layer '0' if the action is undone. Layer '0'
can never be deleted.
Editing Layer Attributes
Toolbar:

Menu:
Layer - Edit Layer
With this command you can trigger the same dialog that you used to
create new layers (Figure 16). Use this to change the layer
name or attributes. The name of the layer '0' cannot be changed.
|