Magic VLSI Layout Tool Version 7.3 *

select


Select or unselect portions of the layout according to the options, or create a new cell definition from a selection.

Shortcuts:

Key macro , (comma) implements the command select clear.
Key macro s implements the command select.
Key macro S implements the command select more.
Key macro Control-S implements the command select less.
Key macro a implements the command select visible.
Key macro A implements the command select more visible.
Key macro Control-A implements the command select less visible.
Key macro i implements the command select cell.
Key macro I implements the command select more cell.
Key macro Control-I implements the command select less cell.

Usage:

select option

where option may be one of the following:
[more | less] [layers]
[De]select material under cursor, or [de]select a subcell if the cursor is over space.
nocycle [layers]
Select material without cycling through different tile types when "select" is called from the same cursor position more than once.
[more | less] area [layers]
[De]select all material under box in layers layers
[more | less] visible [layers]
[De]select all visible material under box in layers layers.
[more | less] box [layers]
[De]select material specified by the boundary of the cursor box
[more | less] chunk [layers]
[De]select a network chunk (largest rectangle) specified by the lower left corner of the cursor box
[more | less] region [layers]
[De]select a network region specified by the lower left corner of the cursor box
[more | less] net [layers]
[De]select an entire electrical network specified by the lower left corner of the cursor box
[more | less] cell [name]
[De]select the cell under cursor, or the cell use (instance) named name.
top cell
Select the topmost cell in the window, which does not have an instance name and therefore cannot be selected with the select cell command.
save cell
Save selection as cell named cell, which is also saved to disk as cell.mag.
clear
Clear selection
pick
Remove the selection from the layout, but retain the selection buffer for interactive processing.
flat
Flatten the contents of the selection buffer.
keep
Copy the selection from the layout into the selection buffer, and keep the selection buffer for interactive processing.
move x y
Move the selection buffer to position x y, relative to the cell definition origin.
help
Print help information

Summary:

The select command changes what material is in the current selection. magic maintains a separate cell definition that represents the current selection. Without the options more or less, the selection is cleared prior to executing the new selection command. Otherwise, more adds to the existing selection and less subtracts from it.

Network selection differs from other types of selection in that magic uses a sophisticated algorithm to determine what is electrically connected together throughout the layout. A chunk is the largest rectangle containing a single layer type. A region is the largest network area containing a single layer type. The region stops where the net connects to a different layer type. The net is the entire electrical network.

The select save options differs from the rest in that it does not alter the current selection, but creates a new cell definition from the current selection. Note that this cell is created as a top-level cell, and does not replace the current selection as a use in the edit cell. To do that requires "select save cell" followed by "delete" and "getcell child 0 0 parent 0 0". The last command syntax is used because the bounds of the selection may differ from the cursor box. The remaining options such as pick, clear, and flat all operate on the selection buffer without clearing the contents of the buffer. They are used primarily by the "pick tool" for interactive copy and paste functions. The following command sequence creates a new cell from the selection and replaces the selected material with the new cell:

select pick
select save cellname
getcell cellname
The following sequence flattens cells within a layout. This differs from both the "flatten" and "dump" commands by being able to flatten a group of cell uses, and being able to directly replace the existing cell with the flattened paint. In effect, it is the reverse of the operation above.
select pick
select flat
select keep

Implementation Notes:

select is implemented as a built-in command in magic. The select keep, select move, and select pick are interactive functions used by the "pick" tool.

See Also:

flatten
dump
tool (Tcl script version)

Bugs:

To be consistent, select save should be a separate command, since like other commands it operates on the selection rather than alter what is in the selection.

Return to command index

Last updated: April 29, 2008 at 2:31pm