xcircuit - Draw circuit schematics or almost anything; make circuit netlists
The program xcircuit is a generic drawing program tailored especially for making
publication-quality renderings of circuit diagrams (hence the name). The
output is pure PostScript, and the graphical interface attempts to maintain as
much consistency as possible between the X11 window rendering and the final
is mouse, menu, and keyboard-driven, with the emphasis on
single-character keyboard macros.
- Begin running xcircuit by loading in the PostScript file filename. If
filename does not have a .ps extension, xcircuit will attempt to look for
both the filename as entered and, upon failure, with the .ps extension.
The file must be in xcircuit format. filename may also be a
comma-separated list of files.
There are five drawing elements. These are as follows:
- polygon (multiple lines which may or may not be closed and filled)
- arc (ellipse segment which may be closed and/or filled as above)
- label (any text)
- curve (based on the PostScript "curveto" algorithm)
- object instance (see below)
There are two composite elements, which are:
- path (a connected series of polygons, arcs, and curves)
- object (something containing polygons, arcs, labels, curves, paths, and
instances of other objects)
The mouse button system, the object library, and the paged buffer system are
loosely based on the Caltech circuit-simulation program "log"
(either "analog" or "diglog").
The general idea is to make the most commonly-used functions the easiest to
perform, and (to the extent possible) to scale (inversely) the complexity of
performing a function with the frequency of that task. Because this program is
tailored to circuit drawing, the most common functions are drawing lines and
moving object instances. The next most common function is selection of
elements singly or in groups.
Mouse button 1 can be tapped to start a connected chain of lines, the most
common drawing function. In addition, button 1 has a function called
"grab", which occurs after the button has been continually pressed
for a short length of time (about 1/5 second). As the name implies,
"grab" grabs hold of an element which can then be moved around the
Button 2 can be used to select an item if tapped, and if pressed and held down,
a box will be drawn and everything inside that box selected when the button is
released. In all other cases, button 2 will complete a command. For users who
have only two mouse buttons and do not emulate the middle mouse button with
the combination of buttons 1 and 3, use the combination of the Shift key and
mouse button 1 to emulate mouse button 2.
Button 3 will normally abort a command. During editing of an arc, spline, or
polygon, button 3 will revert back to the previous form, or abort if there is
no remaining edit history.
All other commands are available from the pulldown menus and/or from the
keyboard using single-key macros (with easy-to-remember mnemonics). Keyboard
commands are quicker, since they act on the present cursor position, whereas
menu commands require an extra step.
The library is intended to provide a convenient way to store and retrieve
elements of a picture which will be used more than once. For the application
of circuit drawing, a built-in library provides basic objects such as
transistors, amplifiers, resistors, capacitors, arrows, circles, power and
ground symbols, and the like. This file is a composite of several library
files (such as "builtins.lps", "analog.lps", and
"digital.lps") which are called by the startup script
("xcstartup.tcl") The program first looks for the startup script in
the current directory, and then searches in the directory given by the
environment variable "XCIRCUIT_LIB_DIR", and finally, in the
hard-coded global directory (/usr/local/lib) if it could not find it
elsewhere. Thus each user can add to or modify the file of builtins to reflect
personal taste. Since the PostScript output contains all object definitions,
these changes to the built-in functions are inherently transferrable. Xcircuit
will automatically resolve conflicts between objects having the same name but
The library is accesible from the pull-down menu or with the "l"
keyboard macro. When inside the library, clicking the first mouse button on an
object "grabs" that object and returns the graphics state
immediately to the page being edited, so that the object will be placed when
the mouse button is released.
Xcircuit has unconstrained zooming and snap-to positioning. Objects scale
completely: line widths and text sizes will increase/decrease proportionally
with the zoom, as well as dot/dash spacing and all other features. Xcircuit
does have a minimum integer grid in coordinate space, which translates to
0.005 inches at an output scale of 1. The maximum zoom scale gives a screen
size translating to about 100 by 100 inches at an output scale of 1. The
effective scale can be varied by changing the output scale (reached from the
"File/Write" menu selection) in order to fit a drawing to a page or
to get a grid matched to a specific dimension. A separate scale parameter
changes the scale of the reported position relative to the output scale (as it
will appear on a printed page).
The snap-to grid is an all-important feature for circuit drawing, wherein it is
critical that elements line up properly with one another. In xcircuit
there is no way to get off the snap-to grid except by turning the snap
function off and physically pushing elements off the grid. Generally, it is
most convenient to leave the snap functon on and use key macros "+"
and "-" to double/halve it as necessary. In any case, objects can
always be returned to the snap grid with the "snap" function (key
Objects are selected using a variety of search methods. The select box (formed
by holding down mouse button 2 and dragging the pointer) uses the simplest
method, searching for curve/polygon segment endpoints, arc centers, and label
and object bounding boxes falling within the select box frame. General object
selection is more complicated. Polygons, Arcs, and Curves are selected by
their outer edges, not the interiors. Currently this is also true for filled
instances of those types. A line is selected if the pointer is in a region
describing a box around it, which is adusted according to the scale (zoom
factor). Every object has an associated bounding box, which is rectangular but
may be rotated with respect to the top level window. An object instance is
selected if the pointer falls within its bounding box. Each label also has a
bounding box carefully calculated from the width of the text string.
Often the selection mechanism will find multiple elements in range of the
pointer. In this case, each object in turn will be presented, colored in blue
(or the specified "querycolor" in the defaults file), and the user
has the option of accepting the highlighted element for selection using the
mouse button 1, or rejecting it with mouse button 3. When all the elements
under consideration have been accepted or rejected, the program proceeds to
execute whatever function was in progress. This selection method takes a
little while to get used to, but is sensible and seems to work well.
Color in xcircuit is implemented with the idea of "color inheritance".
Every page has a "default color" of black. All elements which have
color value "Inherit" will inherit the default color, black. If an
object instance is painted blue (for instance), all components in that object
which have color value "Inherit" will inherit its color, blue. The
reason for this is that it allows different object instances to be painted
different colors (such as if one part of a circuit is highlighted for
emphasis), while making it possible for object instances to be multicolored,
if necessary. Changing the color of an object instance will have no observable
effect on the drawing if none of the components of the object inherit that
color. An object may have both normally colored components and components
which inherit their color, in which case only those components with the
"Inherit" value will change color when the color of the object
instance is changed.
XCircuit implements a sophisticated schematic capture. Unlike virtually all
schematic capture software currently available, xcircuit allows the designer
to draw the circuit in a "natural" way, making use both of schematic
hierarchies and simple hierarchies created simply by grouping elements
together. If the chosen netlist format is hierarchical (like SPICE), both
hierarchical forms will be retained in the output. For element grouping,
input/output ports connecting into to the group will be determined
automatically, from context. A schematic capture tutorial is available from
the xcircuit website,
Netlist types currently available are "SPICE", "sim", and
Basic keyboard commands:
- Zoom in by a factor of 3/2. If this key is pressed while a selection box
is active (created with the middle mouse button), then acts like Zoom Box
- Zoom out by a factor of 3/2.
- Pan the screen so that the point under the mouse is brought to the center
of the program window. This function can also be conveniently performed by
clicking on the scrollbars. The scrollbars cannot be moved continuously
due to the slow time for screen refresh.
- The arrow keys perform a pan of one-half window size in the direction of
the arrow pressed.
- Go to the Library of built-in objects. From the library, use mouse button1
to grab an object and bring it back to the edit screen, or button3 to
return without selecting an object instance. While in the library screen,
the zoom and pan functions can be used to move around.
- Push into an on-screen object in order to edit that object
- Return from editing an object. Object pushes and pops can be stacked
- Refresh the screen.
- digits 0-9
- Switch to one of the first ten editing pages. Pages greater than 10 can be
reached from the "Window/Goto Page" menu selection.
- + and -
- Change snap-to grid spacing by a factor of two up or down.
- | : and _
- (Bar, colon, and underline) Change style on the currently selected object
to dashed, dotted, and solid, respectively.
Commands to create elements:
- h or ?
- Print a help page summary of commands
- Arc. Center is fixed at the initial position of the cursor. The mouse
position changes the radius of the circle. In snap-to mode the arc boundry
will pass through the snap point closest to the cursor. Mouse button 1
cycles from controlling the radius to controlling the starting point, the
ending point, and separately controlling the minor axis to create ellipse.
Mouse button 2 completes the arc.
- Box. This is a convenience function for generating rectangular closed
polygons. Creates a rectangle with one corner fixed at the position of the
cursor. Subsequent movement of the cursor defines the point diametrically
opposed. Mouse buttons 1 or 2 complete the box.
- Spline curve. The first endpoint is defined by the initial cursor
position. Mouse position adjusts the other endpoint of the curve. Mouse
button 1 cycles from controlling position of the endpoint to controlling
positions of the curve control points and the curve starting point. Mouse
button 2 completes the curve.
- Text. Text starts out justified according to the styles chosen in the
pull-down menu. Text can be rejustified using the menu or by typing the
numbers on the keypad ( shift-keypad-1 through
shift-keypad-9). The position of the keys on the keypad matches the
justification. Subscripts, superscripts, font changes, text size changes,
underlining, and overlining are all available from the pull-down menu.
Text edit mode recognizes Home and End keys to move to the
beginning and end of the string, respectively. If the X11 environment maps
control key sequences to character encodings (such as ISO-Latin1), these
may be used to insert non-ASCII text. Another method of inserting
non-ASCII characters is the use of the backslash character, which
duplicates the action of the Text/Insert/Character menu button.
Major editing commands:
- M, m
- Make object. Takes all the elements currently selected and compiles them
into an object. The object is then placed in the user library. The
elements just selected are deleted from the screen and replaced by the new
object. The center point of the resulting object is chosen as the closest
snap-to point to the center of the object's bounding box; if another
center is desired, then the object can be edited using the
">" command and its contents moved with respect to its
origin. Note: Objects cannot have the same name as PostScript
commands or have the same name as any other object in memory. If such a
name is found, an underscore ("_") will be prepended to the name
as many times as is necessary to differentiate it from all other known
objects. The name also cannot contain special PostScript characters such
as slash; any such characters found will be replaced with underscores.
- Delete. Select the nearest element or elements and delete it/them.
- Undelete. Xcircuit saves up to 10 delete events to be recovered. Delete
events are stored in order of occurrence, and the most recent delete event
is the first to be recovered. When multiple elements are deleted at the
same time, all of them are stored as one delete event, and restored
- Deselect. Elements which have been selected can be deselected on a
per-item basis. In order not to be too confusing, deselect does not query
if multiple items are found under the cursor; it just deselects them
- Copy. Make a copy of the object(s) nearest the cursor. Object is
automatically grabbed for moving to a new position. The next button1 or
button2 press will place the element. Button2 will end the copy, and
button1 will continue the copy function.
- Edit. The action of Edit is dependent on the type of element selected.
These are detailed below:
- Returns to text editing mode, starting with the cursor at the end of the
string. Mode is like regular text entry except that Button 3 returns text
to its original string.
- Grabs one point of a polygon for repositioning. Button 1 cycles between
points, button 2 accepts the new polygon, and button 3 returns to the
previous state, unless there is no remaining edit history, in which case
it aborts the command. Key macros available during polygon edit are:
"x"---Breaks the polygon at the given point.
"e"---Moves edit position to the next point.
"i" or "Insert"---Inserts a new point at the position.
"d" or "Delete"---Deletes the current edit point.
There are four modes for polygon editing; see the " Polygon
Edit" section below for details.
- Allows resizing of the radius. Mouse button 1 or the "e" key
will cycle between control of the radius, the endpoint angles, and the
ellipse minor axis. Mouse button 2 accepts the new arc. Button 3 returns
to the previous editing state, unless there is no remaining edit history,
in which case it aborts the command.
- Allows repositioning of one end of the curve. Originally, the starting
angle of the curve is kept fixed. Mouse button 1 or the "e" key
cycles between the four control points of the curve, allowing control over
the angle of the curve at its endpoint and the shape of the curve. Mouse
button 2 accepts the new curve. Button 3 reverts back to the previous edit
state unless there is no remaining edit history, in which case it
terminates the command.
Minor editing commands:
- Object instance
- Object instances have no properties to change except scale, and do not
respond to the "edit" command. Scale can be changed by selecting
"Options/Other/Object Size" from the menu.
- Rotate the selected element(s) or element under the cursor
counterclockwise in 15 degree intervals.
- Rotate the selected element(s) or element under the cursor clockwise in 15
- Rotate the selected element(s) or element under the cursor
counterclockwise by 5 degree intervals. This is currently the smallest
angle resolution available to xcircuit.
- Rotate the selected element(s) or element under the cursor clockwise by 5
- Flip an element around a vertical axis defined by an object's origin for
an object instance, or across an axis defined by the pointer position for
arcs, polygons, and curves.
- Flip an element around a horizontal axis defined similarly to the
- If two elements are selected, their order is exchanged (this is only
relevant if one element occludes another). If one element is selected, it
is raised up one in the stack, and if it is already on top of the stack,
it is shuffled to the bottom.
- Snap the nearest object to the snap-to grid. For curves the control and
endpoints are snapped; for polygons, each point is snapped; for arcs, the
centerpoint is snapped; for labels and object instances, the designated
point of origin is snapped.
- Join polygons together. This only makes sense if it is possible to make a
single continuous (open or closed) polygon from the selected parts.
Otherwise a warning will be posted and the parts will remain
Library editing commands:
- Attach an element to a polygon, arc, or curve. The element to be attached
must be the one currently grabbed (either by a "drag", copy
command, or edit command). Until it is released, it will be forced to
align its center (object, arc), endpoint (polygon, curve), or position
(label) with the closest polygon, arc, or curve. Note that this is a very
powerful tool for generating, for example, lines tangent to a curve, or
objects arranged in a circle or along a line.
- Delete. The selected objects will be deleted from the library unless other
library objects or pages contain references to that object. Note:
Unlike deleting object instances with the " d" command,
this command deletes the actual object and releases all memory associated
with that object, so the object cannot be undeleted.
- Copy. Makes a copy of an object from either library page and places the
new copy in the user library. The new object will be renamed to avoid
- Move. If one object has been selected, it is moved to the position of the
cursor. If two objects have been selected, their positions in the library
- Edit label. Edit the object name whose label is under the cursor. After
editing, the object name will be checked for conflicts with other object
names, and altered if necessary.
- Hide object. If the object is a sub-instance of another object, but is not
meant to be used by itself, it can be "hidden" so that it will
not appear by itself on the library page.
- Write Postscript (W)
- This command brings up a popup menu with a number of options. First, it
gives the name of the file if one exists, or else it gives the default
name of the buffer (usually Page n, where n is the
number of the buffer). Next, it gives a preview of the picture scale and
output styles, which include Landscape/Portrait orientation and
Encapulated/Unencapsulated (full page) PostScript modes. The former allows
adjustment of the nominal size of the picture when drawn in PostScript.
The default scale is 1.00, which makes the text scale of 1.0 about 14
points on the PostScript page. The width and height of the resulting
picture are also given, in inches, and any of the three values can be
changed. The values of the other two will be updated accordingly. Pages
which have the same name will be grouped together into a single file,
allowing multiple pages to be stored in the same PostScript file. However,
as Encapsulated PostScript does not make sense for this kind of file, it
is not an option.
The Write File button writes the current page to an output file. If
the page has a name other than the default, the file will automatically be
saved under that name. Otherwise, it is necessary to change the name of
the buffer. If a file of that name already exists on the disk, the button
will read Overwrite File.
- Read PostScript
- Reads in a file of Xcircuit format. The file name is requested by a popup
prompt, and an extension of ".ps" will be added if necessary.
The file is read into the current page, which is cleared first if anything
is in it. If the file is a multiple-page file, the current page will be
overwritten with the first page from the file, but other pages will be
loaded into empty buffers. Xcircuit can also read "lgf"-format
files from the Chipmunk CAD tools programs "analog" and
- Import PostScript
- Acts like "Read PostScript" except that the page is not reset
first, so graphics are added on top of existing graphics on the page.
- Clear Page
- Clears the current page of all elements and resets the name. The contents
cannot be recovered.
- Alt Color
- Switches between the two xcircuit color schemes. The color schemes can be
redefined through XDefaults (see below). The default color schemes are
black-on-white and white-on-black. The latter is less straining to the
eyes, but the former matches the black ink on white paper PostScript
output. Any color scheme other than black-on-white is not recommended for
drawings with color, as the actual output does not match the observed
- Turns the grid lines on and off.
- Turns the axis lines on and off. The axes mark the origin (0,0) of the
page. On the top level (TopObject), the origin has no particular
relevance, since encapsulated output will define its own boundaries, and
full-page (unencapsulated) output will be centered on the output page, not
according to the Xcircuit coordinate system.
- Grid spacing
- Changes the spacing of the grid lines. Default spacing is 1/6 inch, which
is about the width of the letter 'W' in default text scale.
- Grid type/display
- This is a submenu allowing the coordinates and coordinate grid to be
specified in alternate units. Listing of coordinates in the top window can
be in default fractional inches, decimal inches, or centimeters. Default
spacing of grid lines is either one-quarter inch or one-half centimeter.
Selecting an A:B scale With option " Drawing Scale"
causes all listed coordinates to be multiplied by the scale. Note:
Xcircuit will make an attempt to keep objects on the snap/grid spacing
when switching between inch and centimeter scales. In order to do this, it
will change the output scale by the ratio of 2.54 to 2.5, thus keeping a
closer correspondence between inches and centimeters. To get true
centimeters on the output page, the output scale (from the
"File/Write Xcircuit PS") can be reset to 1.0 at the expense of
having all objects intended for the inch grid displaced off of the snap
- Turns the snap-to grid on and off. When the grid is on, movement and
placement of elements is restricted to points on the snap-to grid.
- Snap spacing
- Determines the spacing of the points in the snap-to grid. Default is 1/12
inch, which is half the grid line spacing.
- Controls the default linewidth against which all linewidths in the drawing
- Polygon Edit
- The options in this submenu control how the position of lines are affected
when a point in a polygon is selected for editing. "
Rhomboid-X" mode moves adjoining points as necessary to keep
all horizontal lines horizontal; " Rhomboid-Y" mode acts
similarly to keep all vertical lines vertical. "
Rhomboid-A" is similar to Manhattan mode but also tracks
non-Manhattan lines. The default mode is " Manhattan Box
Edit", which is a combination of Rhomboid-X and Rhomboid-Y. In
" Normal" mode, only the point being edited can be
- Arc/Box/Curve Border
- The options under this menu determine the border style of arcs, polygons,
and curves. If an element is selected, it will be modified; otherwise, if
no objects are selected, the style chosen is made default for all
subsequent arcs, polygons, and curves. Elements may be drawn with or
without borders (but for obvious reasons cannot be made both borderless
and unfilled, which would be invisible) The borders may be closed or
unclosed. For an arc, closed means that a chord is drawn connecting the
two endpoints, if the beginning and ending angles do not complete a full
circle. Borders may be solid, dashed, dotted, and of varying width.
- Arc/Box/Curve Fill
- The options under this menu determine the fill style of arcs, polygons,
and curves. Fill style may be solid, empty, or one of 7 stipple patterns
varying from light to dark, which are drawn both in xcircuit and
PostScript as stipple patterns. Stipples can be transparent or opaque.
Warning: Transparent stipples are NOT inherent to PostScript and
the hacks necessary to implement them cause slow rendering on a printer or
PostScript previewer. Due to the device-dependent nature of the routines,
patterns will look abnormally large on PostScript previewers. This
transparancy feature has been added with the expectation that most circuit
schematics will not rely heavily upon halftoning. Complicated color
patterns can be created using transparent colored, stippled elements on
top of solid-color elements. Note: Ordering of elements is
according to order created. A different ordering can be achieved using the
" X" (exchange) command. This method is not especially
easy to work with, and hopefully something better will be implemented in
- Arc/Box/Curve Color
- See the COLOR section above for a discussion of color inheritance. This
menu shows all the colors available to xcircuit with the option of adding
more colors. Currently the entry style for colors is by name or by RGB
content in the X11 style of #rrggbb where rr, gg, and bb are hex values
ranging from 00 to FF. The only limit to the number of colors is the X
Server's colormap depth. If the colormap is full, xcircuit attempts to
allocate the closest possible color to the one requested.
- Zoom Box
- This zoom feature requests the user to create a box (using either mouse
button 1 or 2, expanding the box while holding down the button). When the
button is released, the view will zoom to the area of that box.
- Full View
- This zoom feature calculates the bounding box of the entire picture and
adjusts the scale to make it fit comfortably inside the program
Xcircuit's ability to handle text is arguably the most complicated part of the
program, and also of the PostScript output. Careful attention to text
justification and style is the key to a good drawing.
- Text Size
- Alters the size of the labels. The value is a scale, with a default of 1.0
which translates to 14 points on the PostScript page if the default page
scale of 1 is used. If a label is selected, only that label is affected.
If a label is being edited, scale changes starting at the edit position.
Otherwise, it becomes the default size for all subsequent labels. Size
affects the entire text string. Text size can be changed anywhere inside
of a string. However, text sizes inside a string are all given relative to
the label size, not as an absolute point size. Sizes of subscripts and
superscripts are given relative to the natural size of the subscript or
superscript (2/3 the size of the text for which it is a modifier).
- Text Font
- Standard printer fonts Times-Roman, Helvetica, Courier, and Symbol, are
readily available. "User-defined" fonts can also be added;
however, support is currently limited, and requires a font object (.lps)
file and encoding (.xfe) file, examples of which are found in the fonts
subdirectory of the xcircuit library directory.
- Text Style
- Four standard font styles are available, matching the standard printer
font variations: Normal, Italic (or oblique), Bold, and BoldItalic.
PostScript matrix manipulation allows slanted versions of any font, such
as Symbol, for which none is otherwise available.
- Text Insert
- The Insert menu allows insertion of special characters which are otherwise
not (necessarily) allowed from the keyboard. These include tab-stop,
tab-forward, tab-backward, kern, half-space, quarter-space, and
"Character". The latter option brings up a page showing the
256-character encoding vector for the font, allowing point-and-click entry
of any character in the font. "Kern" instructions allow
characters to be offset vertically or horizontally relative to the rest of
- Text Encoding
- Two standard font encodings are available by default, Standard (Adobe)
Encoding, and ISO-Latin1 encoding. ISO-Latin2 and ISO-Latin5 encodings
exist in the library directory, but require the use of the program
"ogonkify" (not included) to produce correct output on a
- Super and Subscripts
- Superscript and subscript are designed to closely match those in TeX
output, though they lack the proper context-dependent kerning and other
fancy features of TeX. A superscript following a subscript results in a
superscripted subscript. To get a superscript on top of a subscript, use
the backspace character (see below). The Normalscript style is the way to
get out of a sub or superscript and return to the normal size and
position. Quick super/sub/normalscripting is available from the keypad
with the " +" (plus), "-" (minus), and
" Enter" keys, respectively.
- Overline and Underline
- Overlining and underlining styles remain in effect until the next
occurrence of a style or font change. Overlining is lower if all the
characters are lowercase and do not include the "tall" lowercase
characters. Overlining or underlining can be stopped at any time using the
No Line style. Over and Underlining is *always* preferable to using a
line. PostScript will adjust the over or underline to the text size and
extent and actually grab the "_" character and compute its
thickness in order to draw the line.
- From version 2.3, xcircuit allows embedded tab stops. Tab stops must be
defined before using tab-forward or tab-backward. The "Tab"
keyboard key inserts an embedded tab-forward instruction into a label.
Tab-stop and tab-backward can be inserted using the Text->Insert menu.
A tab-forward instruction moves the cursor to the first defined tab stop
forward of the current position. A tab-backward instruction moves the
cursor to the first defined tab stop backward of the current position. If
no appropriate tab stop exists, the instruction has no effect.
- The use of the backspace character is deprecated from xcircuit version
2.3. The effect of an embedded backspace is more reliably produced using
tab-stop and tab-backward.
- Halfspace and Quarterspace
- These options allow fine control over spacing, particularly useful when
- Text justification always starts with the default, chosen from the options
in the menu, but may be changed at any time using the numbers on the
keypad. The position of the keys on the keypad reflect the point of
justification: 1, 4, and 7 are right-justified, 7, 8, and 9 are bottom
justified, 5 is centered in both directions. Since the letters drawn by
xcircuit are optimized for the Helvetica font, correct justification is
the main way to get text to come out on the PostScript page in the desired
way, relative to objects or boxes or whatever.
Certain parameters of the xcircuit program can be initialized from a file called
, which is first searched for in the current directory, and
then in the user's home directory as defined by the environment variable
The startup file is written in Tcl. The command-line interface can be found in
the online documentation on the website
XCircuit implements a crash recovery system by which a copy of the current file
is made every 15 minutes (see Xdefaults, below, for changing this value).
XCircuit deletes this file upon a normal exit. If, however, XCircuit crashes
or is terminated by Control-C or other sudden death, the backup copy will
remain. On startup, XCircuit checks the /tmp directory for any XCircuit backup
files belonging to the user. If one is found, XCircuit will prompt the user
for recovery. Note that the backup is unique in that it contains a copy of the
entire user space at the time of the crash. Filenames may get overwritten, as
the backup will treat all pages as belonging to the same file.
As noted above, keys can be bound and unbound through command-line functions
"bind" and "unbind". Default key bindings are used
throughout this manual page. Key names use the notation of
/usr/X11R6/include/keysymdef.h, but with the notation "XK_" being
optional, and including the addition of prefixes "Shift_",
"Control_", "Capslock_", and "Alt_", which may
be used in any combination. Note that "Shift_" is not used for ASCII
characters (e.g., "A" is used instead of "Shift_a") unless
used in combination with other special keys (such as
"Control_Shift_A" to distinguish from "Control_a", should
that be desired). "Button1", "Button2", and
"Button3" are also valid names indicating functions attached to the
mouse buttons in normal drawing mode. Valid functions which may be bound are
as follows, with their default values given:
Function name Function performed Default key binding
"Page", change page, Number keys 1-9 and 0
"Justify", change text justification, Keypad keys 1-9
"Superscript", set text superscript, Keypad +
"Subscript", set text subscript, Keypad -
"Normalscript", cancel sub/superscript, Keypad Enter
"Nextfont", change to next font, Alt-f
"Boldfont", change to bold font, Alt-b
"Italicfont", change to italic font, Alt-i
"Normalfont", cancel italic/bold, Alt-n
"Underline", generate underline, Alt-u
"Overline", generate overline, Alt-o
"ISO Encoding", change to ISO encoding, Alt-e
"Return", embedded return character, Alt-Enter
"Halfspace", embedded half-space, Alt-h
"Quarterspace", embedded quarter-space, Alt-q
"Special", special character, Alt-c
"Parameter", embedded parameter, Alt-p
"Edit Break", break at point, x
"Edit Delete", delete point, d, Delete
"Edit Insert", insert point, i, Insert
"Edit Next", go to next point, e
"Attach", attach line to object, A
"Next Library", go to next library, l
"Library Directory", library directory, L
"Library Move", arrange library objects, M
"Library Copy", get object in copy mode, c
"Library Edit", edit library name, E
"Library Delete", delete library object, D
"Library Duplicate", duplicate object, C
"Library Hide", hide library object, H
"Page Directory ", page directory, P
"Library Pop", return from library, <
"Help", generate help screen, h, ?
"Redraw", redraw the window, space
"View", fit page to window, v
"Zoom In", zoom in, Z
"Zoom Out", zoom out, z
"Pan", center pan, p
"Double Snap", increase snap space, +
"Halve Snap", decrease snap space, -
"Pan Left", pan left one-half page, Left arrow
"Pan Right", pan right one-half page, Right arrow
"Pan Up", pan up one-half page, Up arrow
"Pan Down", pan down one-half page, Down arrow
"Write", popup output window, W
"Rotate", Rotate, r,R,o,O
"Flip X", Flip horizontal, f
"Flip Y", Flip vertical, F
"Snap", Snap to grid, S
"Pop", Return from object edit, <
"Push", Edit object, >
"Delete", Delete element, d
"Select", Select element, Select
"Box", Create box, b
"Arc", Create arc, a
"Text", Create label, t
"Exchange", Exchange vertical order, X
"Copy", Copy element, c
"Join", Join into path, j
"Unjoin", Split path into elements, J
"Spline", Create spline, s
"Edit", Edit element, e
"Undelete", Undelete last deleted, u
"Select Save", Make object from selected, M,m
"Unselect", Unselect element, x
"Dashed", Set line style to dashed, |
"Dotted", Set line style to dotted, :
"Solid", Set line style to solid, _
"Prompt", Execute from command line, %
"Dot", Place dot at location, .
"Exit", Exit xcircuit Ctrl-Alt-q
"Netlist", Generate a netlist, Alt-q
"Swap", Swap schematic, symbol, /
"Pin Label", Create pin label, T
"Info Label", Create info label, I
"Connectivity", Show wire connectivity, Alt-w
"Sim", Generate sim netlist, Alt-s
"SPICE", Generate SPICE netlist, Alt-S
"PCB", Generate PCB netlist, Alt-p
"SPICE Flat" Generate flattened SPICE, Alt-f
2-Button mouse users may find it useful to forego the Shift-Button1 combination
and instead put the following commands in the startup script:
This will move the 3rd mouse button bindings to the "Escape" key, and
duplicate the 2nd mouse button bindings onto the 3rd.
The color scheme of xcircuit has a default setup, but accepts alternate color
schemes using the following keywords which can be put in the X Defaults
(.Xdefaults, .Xresources) file, such as:
! Sample X defaults for xcircuit, black-on-white version
xcircuit*foreground : Black
xcircuit*background : White
xcircuit*gridcolor : Gray85
xcircuit*snapcolor : Orange
xcircuit*selectcolor : Blue
xcircuit*querycolor : Green
xcircuit*axescolor : NavajoWhite3
xcircuit*offbuttoncolor : Gray30
xcircuit*auxiliarycolor : MediumOrchid1
Two color schemes are supported at a time, ostensibly for those people who
prefer the lessened eye strain of a white-on-black scheme. The names of the
secondary colors are the same as those for the primary colors, but followed by
"2", e.g., "xcircuit*foreground2".
One other resource defines the number of minutes between automatic saves to the
temporary file (in case of a crash or emergency Ctrl-C exit):
xcircuit.timeout : 15
Xcircuit also recognizes the core resources, such as width and height:
xcircuit.width : 600
xcircuit.height : 500
All xcircuit foreground and background colors are taken from the Xdefaults
foreground and background. To get, for instance, white-on-black menus and
buttons with a black-on-white drawing area, use the following:
xcircuit*foreground : White
xcircuit*background : DarkSlateGray
xcircuit.foreground : Black
xcircuit.background : White
This will ensure that only the drawing area is black-on-white, but all other
windows will appear in the less eye-straining white-on-black.
Five different fonts can be specified in the Xdefaults. helpfont is
the style of fonts on the help popup window. filefont is the style
of fonts in the list of files in the file selection popup window. textfont
is the style of font for entering text in the popup dialog boxes. titlefont
is the style of font for the cascade menu titles. All other fonts take the
type font. For example:
xcircuit*font : *times-bold-r-normal--14*
xcircuit*helpfont : *times-medium-r-normal--12*
xcircuit*filefont : *times-medium-r-normal--14*
xcircuit*textfont : *courier-medium-r-normal--14*
xcircuit*titlefont : *times-bold-r-normal--18*
The file path used by xcircuit to find library files is system-dependent (i.e.,
can be changed at compile time), and can be overridden in many ways (in
.xcircuitrc or by the XCIRCUIT_LIB_DIR environment variable), but by default
- PostScript prolog appended to each file
- This startup script contains commands of the type library
name number which cause the designated library name
to be immediately loaded into library page number. The startup
script is also responsible for loading fonts, and may also be used to load
colors on the color palette, set other options, and execute commands.
- generic.lps, analog.lps, digital.lps, avlsi.lps,
- Files containing pre-compiled circuit elements. The .lps extension
is unique for xcircuit libraries.
- This subdirectory contains font definition files for xcircuit's
vector-drawn fonts. Characters are defined by xcircuit objects and stored
in a .lps library. The encoding scheme and other font information
is stored in a .xfe ("xcircuit font encoding") file.
- ~/.xcircuitrc or ./xcircuitrc
- Personal xcircuit initializer; commands are outlined above. Libraries
listed in this file will be appended to the builtin libraries.
understands the following environment variables:
- Directory for temporary (e.g., backup) files (defaults to TEMP_DIR).
- Directory where xcircuit libraries and startup files can be found
(defaults to BUILTINS_DIR).
- Directory where the xcircuit application defaults can be found (defaults
- Directory where xcircuit will look for startup files, after searching the
- HOST, HOSTNAME, USER
- Environment variables which xcircuit uses to fill in header information in
the PostScript output (HOST and HOSTNAME are equivalent).
PostScript printers have device-dependent limits on the number of statements
within a "def" definition. If an object definition has an unusually
large number of components, xcircuit will flag a warning when writing the
file. However, there is no way to ensure that a file will be accepted by a
given printer. The best way to avoid the problem is to make sure that large
drawings make good use of hierarchically nested user-defined objects. Note
that printer errors arising from this problem have not been observed in
practice, and given the typical size of on-board memory on most modern laser
printers, probably never will be.
A list of bugs can be found in the Manifest file in the source directory.
Look for the xcircuit online tutorial at
xfig(1), another powerful freeware drawing program worthy of mention (see
www.xfig.org). Another schematic capture package worth noting is
"gschem" from the gEDA package (see www.geda.seul.org).
PostScript is a registered trademark of Adobe Systems Incorporated.
XCircuit Copyright (c) 2002 Tim Edwards. XCircuit is freely distributed under a
generous public license. See the source distribution for details.
Xw widget set Copyright (c) 1988 by Hewlett-Packard Company and the
Massachusetts Institute of Technology.
Tim Edwards <email@example.com>. Thanks to Tomas Rokicki for the
PostScript routine which manufactures a Symbol-Oblique font. Thanks to Dave
Gillespie and John Lazzaro for the program "analog" on which the
graphical interface of xcircuit is (roughly) based. Thanks to many
beta-testers, some of whom were kind enough to send patches. Most contributors
have been named in the Manifest file in the source distribution.