Table of Contents
xcircuit - Draw circuit schematics or almost anything; make circuit
netlists from schematics.
xcircuit [filename[,...]]
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 printer output.
xcircuit is mouse, menu, and keyboard-driven, with
the emphasis on single-character keyboard macros.
- filename[,...]
- 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:
- a)
- polygon (multiple lines which may or may not be closed and filled)
- b)
- arc (ellipse segment which may be closed and/or filled as above)
- c)
- label (any text)
- d)
- curve (based on the PostScript "curveto" algorithm)
- e)
- object instance (see below)
There are two composite elements, which
are:
- f)
- path (a connected series of polygons, arcs, and curves)
- g)
- 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 screen.
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 ("startup.script") 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 (LIBDIR) 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 different contents.
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 macro "S").
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,
http://xcircuit.ece.jhu.edu/tutorial/tutorial2.html.
Netlist types currently available are "SPICE", "sim", and "PCB".
Basic keyboard commands:
- Z
- 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 function.
- z
- Zoom out by a factor of 3/2.
- p
- 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.
- cursors
- The arrow keys perform a pan of one-half
window size in the direction of the arrow pressed.
- l
- 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 indefinitely.
- space
- 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.
- h or ?
- Print a help page summary of commands
Commands to create elements:
- a
- 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.
- b
- 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.
- s
- 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.
- t
- 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.
- 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.
Major
editing commands:
- d
- Delete. Select the nearest element or elements and
delete it/them.
- u
- 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 together.
- x
- 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 all.
- c
- 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.
- e
- Edit. The action of Edit is dependent
on the type of element selected. These are detailed below:
- Label
- 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.
- Polygon
- 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.
- Arc
- 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.
- Curve
- 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.
- 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.
Minor
editing commands:
- R
- Rotate the selected element(s) or element under the
cursor counterclockwise in 15 degree intervals.
- r
- Rotate the selected element(s)
or element under the cursor clockwise in 15 degree intervals.
- O
- 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.
- o
- Rotate the selected element(s) or element under the cursor clockwise
by 5 degree intervals.
- f
- 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.
- F
- Flip an element
around a horizontal axis defined similarly to the "f" command.
- X
- 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.
- S
- 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.
- j
- 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 separate.
- A
- 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.
Library editing
commands:
- D
- 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.
- C
- 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 naming conflicts.
- M
- 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 are exchanged.
- E
- 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.
- H
- 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. if(,1,Xcircuit can also read "lgf"-`format'
files from the Chipmunk CAD tools programs "analog" and "diglog".)
- 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 xcircuit screen.
- Grid
- Turns the grid lines on and off.
- Axes
- 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 grid.
- Snap-to
- 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.
- Linewidth
- Controls the default linewidth against
which all linewidths in the drawing are scaled.
- 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 moved.
- 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
the future.
- 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 window.
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 the text.
- 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 printer.
- 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.
- Tabbing
- 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.
- Backspace
- 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
writing equations.
- Justification
- 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 .xcircuitrc, which is first searched for in the current directory,
and then in the user's home directory as defined by the environment variable
$HOME. Commands are:
- library libname
- Loads a library named libname (with
or without .lps extension) into the set of built-in objects.
- override default
library
- Causes the default libraries defined in "builtins.lps" not to be
loaded.
- override default colors
- Causes the default colors not to be loaded;
this will not override the allocation of black and white, however, for
obvious reasons.
- font fontname
- Adds a font named fontname (as recognized
by a printer) to the menu of selectable fonts.
- color colorname
- Adds a color
named colorname (standard X11 conventions) to the menu of selectable colors.
- set type value
- Sets internal xcircuit variables, where type can be one
of:
boxedit
Where value is one of "manhattan", "rhomboid-x", "rhomboid-y",
or "normal". Determines the default way manhattan-aligned polygon edges
are manupulated during edits.
linewidth
Where value is a real number indicating
the default width of lines.
beep
Where value can be on or off, depending
on whether or not you want the machine beeping at you when it gives critical
warnings.
colorscheme
Where value is inverse to swap the two color schemes
and make the second scheme appear as default.
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
------------------------------------------------------------------
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 is:
- LIBDIR
- xcircps2.pro
- PostScript prolog appended to each file
- startup.script
- 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,
analoglib2.lps
- Files containing pre-compiled circuit elements. The .lps extension
is unique for xcircuit libraries.
- fonts
- 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.
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
http://xcircuit.ece.jhu.edu/tutorial/tutorial.html
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) 2001 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 <tim@bach.ece.jhu.edu>. 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.
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