The lpal button in the top button menu will bring up the layer palette. The layer palette is an adjunct to the layer table which provides a means for quick access to a few ``important'' layers, and prints information about layers. This is particularly useful when working with technologies containing a large number of layers, to avoid hunting through the layer table. When the mouse pointer hovers over a layer indicator in the layer table or in the palette, information about that layer is printed in the top part of the palette.
The layer palette consists of three logical sections. The top section is a text area that displays information about the layer currently or was last under the mouse pointer. The user can move the pointer over the layer icons in the layer table or the palette, and the palette will display the information. The information printed includes the alias and description of the layer, and the GDSII mapping layer/datatype numbers.
In the lower section, there are four rows of locations for layer indicators. The indicators in this section can be dragged and clicked on in the same manner and same functionality as layers in the layer table. The top row contains layer indicators for the last five choices of current layer. This row is automatically updated whenever the user selects a current layer by any means.
The three rows below can be filled by the user, by dragging/dropping layers from the layer table, or from the top row in the palette. Layers in these rows can be dragged/dropped within the rows to change the listing order. A layer indicator can be removed from these rows by pressing the Remove button at the top of the panel, then clicking on a layer indicator in this area. The indicator will disappear, and the Remove button will become unselected.
In order to conserve space, only the index number of the layer in the layer table is shown with the layer sample box in the layer palette. The layer's name and other information can be obtained by hovering over the indicator with the mouse pointer.
The palette layers can be saved in one of seven registers and restored later, with the Save and Restore buttons. There are separate registers for physical and electrical modes, so that the same register number can be used in each mode. The current palette is saved when the palette is dismissed, and restored when the palette is popped up again.
These registers are saved in a technology file created with the Save Tech button in the Attributes Menu. The corresponding technology file keywords are PhysLayerPalette1 - PhysLayerPalette7 and ElecLayerPalette1 - ElecLayerPalette7. Each keyword can be set to a space-separated list of layer names, representing the content and order of the layers in the register.