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X(1)



BITMAP(1)                       X11 R4.11MU05                      BITMAP(1)


NAME
       bitmap, bmtoa, atobm - bitmap editor and converter utilities for X


SYNOPSIS
       bitmap [-options ...] filename WIDTHxHEIGHT

       bmtoa [-chars ...] [filename]

       atobm [-chars cc] [-name variable] [-xhot number]
             [-yhot number] [filename]

DESCRIPTION
       The bitmap program is a rudimentary tool for creating or editing
       rectangular images made up of 1's and 0's.  Bitmaps are used in X for
       defining clipping regions, cursor shapes, icon shapes, and tile and
       stipple patterns.

       The bmtoa and atobm filters convert bitmap files (FILE FORMAT) to and
       from ASCII strings.  They are most commonly used to quickly print out
       bitmaps and to generate versions for including in text.

USAGE
       Bitmap displays grid in which each square represents a single bit in
       the picture being edited.  Squares can be set, cleared, or inverted
       directly with the buttons on the pointer and a menu of higher level
       operations such as draw line and fill circle is provided to the side
       of the grid.  Actual size versions of the bitmap as it would appear
       normally and inverted appear below the menu.

       If the bitmap is to be used for defining a cursor, one of the squares
       in the images may be designated as the hotspot.  This determines
       where the cursor is actually pointing.  For cursors with sharp tips
       (such as arrows or fingers), this is usually at the end of the tip;
       for symmetric cursors (such as crosses or bullseyes), this is usually
       at the center.

       Bitmaps are stored as small C code fragments suitable for including
       in applications.  They provide an array of bits as well as symbolic
       constants giving the width, height, and hotspot (if specified) that
       may be used in creating cursors, icons, and tiles.

       The WIDTHxHEIGHT argument gives the size to use when creating a new
       bitmap (the default is 16x16).  Existing bitmaps are always edited at
       their current size.

       If the bitmap window is resized by the window manager, the size of
       the squares in the grid will shrink or enlarge to fit.

OPTIONS
       Bitmap accepts the following options:

       -help
           This option will cause a brief description of the allowable
           options and parameters to be printed.

       -display display
           This option specifies the name of the X server to used.

       -geometry geometry
           This option specifies the placement and size of the bitmap window
           on the screen.  See X for details.

       -nodashed
           This option indicates that the grid lines in the work area should
           not be drawn using dashed lines.  Although dashed lines are
           prettier than solid lines, on some servers they are significantly
           slower.

       -name variablename
           This option specifies the variable name to be used when writing
           out the bitmap file.  The default is to use the basename of the
           filename command line argument.

       -bw number
           This option specifies the border width in pixels of the main
           window.

       -fn font
           This option specifies the font to be used in the buttons.

       -fg color
           This option specifies the color to be used for the foreground.

       -bg color
           This option specifies the color to be used for the background.

       -hl color
           This option specifies the color to be used for highlighting.

       -bd color
           This option specifies the color to be used for the window border.


       Bmtoa accepts the following option:

       -chars cc
           This option specifies the pair of characters to use in the string
           version of the bitmap.  The first character is used for 0 bits
           and the second character is used for 1 bits.  The default is to
           use dashes (-) for 0's and sharp signs (#) for 1's.

       Atobm accepts the following options:

       -chars cc
           This option specifies the pair of characters to use when
           converting string bitmaps into arrays of numbers.  The first
           character represents a 0 bit and the second character represents
           a 1 bit.  The default is to use dashes (-) for 0's and sharp
           signs (#) for 1's.

       -name variable
           This option specifies the variable name to be used when writing
           out the bitmap file.  The default is to use the basename of the
           filename command line argument or leave it blank if the standard
           input is read.

       -xhot number
           This option specifies the X coordinate of the hotspot.  Only
           positive values are allowed.  By default, no hotspot information
           is included.

       -yhot number
           This option specifies the Y coordinate of the hotspot.  Only
           positive values are allowed.  By default, no hotspot information
           is included.

CHANGING GRID SQUARES
       Grid squares may be set, cleared, or inverted by pointing to them and
       clicking one of the buttons indicated below.  Multiple squares can be
       changed at once by holding the button down and dragging the cursor
       across them.  Set squares are filled and represent 1's in the bitmap;
       clear squares are empty and represent 0's.  Note: when the pointer is
       in the grid border, the closest square will be changed.

            Button 1
                This button (usually leftmost on the pointer) is used to set
                one or more squares.  The corresponding bit or bits in the
                bitmap are turned on (set to 1) and the square or squares
                are filled.

            Button 2
                This button (usually in the middle) is used to invert one or
                more squares.  The corresponding bit or bits in the bitmap
                are flipped (1's become 0's and 0's become 1's).

            Button 3
                This button (usually on the right) is used to clear one or
                more squares.  The corresponding bit or bits in the bitmap
                are turned off (set to 0) and the square or squares are
                emptied.

MENU COMMANDS
       To make defining shapes easier, bitmap provides 13 commands for
       drawing whole sections of the grid at once, 2 commands for
       manipulating the hotspot, and 2 commands for updating the bitmap file
       and exiting.  A command buttons for each of these operations is
       located to the right of the grid.

       Several of the commands operate on rectangular portions of the grid.
       These areas are selected after the command button is pressed by
       moving the cursor to the upper left square of the desired area,
       pressing a pointer button, dragging the cursor to the lower right
       hand corner (with the button still pressed) , and then releasing the
       button.  The command may be aborted by pressing any other button
       while dragging or by releasing outside the grid.

       To invoke a command, move the pointer over that command and click any
       button.

            Clear All
                This command is used to clear all of the bits in the bitmap
                as if Button 3 had been dragged through every square in the
                grid.  It cannot be undone.

            Set All
                This command is used to set all of the bits in the bitmap as
                if Button 1 had been dragged through every square in the
                grid.  It cannot be undone.

            Invert All
                This command is used to invert all of the bits in the bitmap
                as if Button 2 had been dragged through every square in the
                grid.

            Clear Area
                This command is used to clear a region of the grid as if
                Button 3 had been dragged through each of the squares in the
                region.  When this command is invoked, the cursor will
                change shape to indicate that the area to be cleared should
                be selected as outlined above.

            Set Area
                This command is used to set a region of the grid as if
                Button 1 had been dragged through each of the squares in the
                region.  When this command is invoked, the cursor will
                change shape to indicate that the area to be set should be
                selected as outlined above.

            Invert Area
                This command is used to inverted a region of the grid as if
                Button 2 had been dragged through each of the squares in the
                region.  When this command is invoked, the cursor will
                change shape to indicate that the area to be inverted should
                be selected as outlined above.

            Copy Area
                This command is used to copy a region of the grid from one
                location to another.  When this command is invoked, the
                cursor will change shape to indicate that the area to be
                copied should be selected as outlined above.  The cursor
                should then be clicked on the square to which the upper left
                hand corner of the region should be copied.

            Move Area
                This command is used to move a region of the grid from one
                location to another.  When this command is invoked, the
                cursor will change shape to indicate that the area to be
                moved should be selected as outlined above.  The cursor
                should then be clicked on the square to which the upper left
                hand corner of the region should be moved.  Any squares in
                the region's old position that aren't also in the new
                position are cleared.

            Overlay Area
                This command is used to copy all of the set squares in a
                region of the grid from one location to another.  When this
                command is invoked, the cursor will change shape to indicate
                that the area to be copied should be selected as outlined
                above.  The cursor should then be clicked on the square to
                which the upper left hand corner of the region should be
                overlaid.  Only the squares that are set in the region will
                be touched in the new location.

            Line
                This command will set the squares in a line between two
                points.  When this command is invoked, the cursor will
                change shape to indicate that the pointer should be clicked
                on the two end points of the line.

            Circle
                This command will set the squares on a circle specified by a
                center and a point on the curve.  When this command is
                invoked, the cursor will change shape to indicate that the
                pointer should be clicked on the center of the circle and
                then over a point on the curve.  Small circles may not look
                very round because of the size of the grid and the limits of
                having to work with discrete pixels.

            Filled Circle
                This command will set all of the squares in a circle
                specified by a center and a point on the curve.  When this
                command is invoked, the cursor will change shape to indicate
                that the pointer should be clicked on the center of the
                circle and then over a point on the curve.  All squares side
                and including the circle are set.

            Flood Fill
                This command will set all clear squares in an enclosed
                shape.  When this command is invoked, the cursor will change
                shape to indicate that the pointer should be clicked on any
                empty square inside the shape to be filled.  All empty
                squares that border horizontally or vertically with the
                indicated square are set out to the enclosing shape.  If the
                shape is not closed, the entire grid will be filled.

            Set Hot Spot
                This command designates one square in the grid as the hot
                spot if this bitmap to be used for defining a cursor.  When
                the command is invoked, the cursor will change indicating
                that the pointer should be clicked on the square to contain
                the hot spot.

            Clear Hot Spot
                This command removes any designated hot spot from the
                bitmap.


            Write Output
                This command writes a small fragment of C code representing
                the bitmap to the filename specified on the command line.
                If the file already exists, the original file will be
                renamed to filename~ before the new file is created.  If an
                error occurs in either the renaming or the writing of the
                bitmap file, a dialog box will appear asking whether or not
                bitmap should use /tmp/filename instead.


            Quit
                This command causes bitmap to display a dialog box asking
                whether or not it should save the bitmap (if it has changed)
                and then exit.  Answering yes is the same as invoking Write
                Output; no causes bitmap to simply exit; and cancel will
                abort the Quit command so that more changes may be made.

FILE FORMAT
       The Write Output command stores bitmaps as simple C program fragments
       that can be compiled into programs, referred to by X Toolkit pixmap
       resources, manipulated by other programs (see xsetroot), or read in
       using utility routines in the various programming libraries.  The
       width and height of the bitmap as well as the hotspot, if specified,
       are written as preprocessor symbols at the start of the file.  The
       bitmap image is then written out as an array of characters:

               #define name_width 11
               #define name_height 5
               #define name_x_hot 5
               #define name_y_hot 2

               static char name_bits[] = {
                   0x91, 0x04, 0xca, 0x06, 0x84,
                   0x04, 0x8a, 0x04, 0x91, 0x04
               };

       The name prefix to the preprocessor symbols and to the bits array is
       constructed from the filename argument given on the command line.
       Any directories are stripped off the front of the name and any suffix
       beginning with a period is stripped off the end.  Any remaining non-
       alphabetic characters are replaced with underscores.  The name_x_hot
       and name_y_hot symbols will only be present if a hotspot has been
       designated using the Set Hot Spot command.

       Each character in the the array contains 8 bits from one row of the
       image (rows are padded out at the end to a multiple of 8 to make this
       is possible).  Rows are written out from left to right and top to
       bottom.  The first character of the array holds the leftmost 8 bits
       of top line, and the last characters holds the right most 8 bits
       (including padding) of the bottom line.  Within each character, the
       leftmost bit in the bitmap is the least significant bit in the
       character.

       This process can be demonstrated visually by splitting a row into
       words containing 8 bits each, reversing the bits each word (since
       Arabic numbers have the significant digit on the right and images
       have the least significant bit on the left), and translating each
       word from binary to hexadecimal.

       In the following example, the array of 1's and 0's on the left
       represents a bitmap containing 5 rows and 11 columns that spells X11.
       To its right is is the same array split into 8 bit words with each
       row padded with 0's so that it is a multiple of 8 in length (16):

                     10001001001            10001001 00100000
                     01010011011            01010011 01100000
                     00100001001            00100001 00100000
                     01010001001            01010001 00100000
                     10001001001            10001001 00100000

       Reversing the bits in each word of the padded, split version of the
       bitmap yields the left hand figure below.  Interpreting each word as
       hexadecimal number yields the array of numbers on the right:

                      10010001 00000100            0x91 0x04
                      11001010 00000110            0xca 0x06
                      10000100 00000100            0x84 0x04
                      10001010 00000100            0x8a 0x04
                      10010001 00000100            0x91 0x04

       The character array can then be generated by reading each row from
       left to right, top to bottom:

               static char name_bits[] = {
                  0x91, 0x04, 0xca, 0x06, 0x84,
                  0x04, 0x8a, 0x04, 0x91, 0x04
               };

       The bmtoa program may be used to convert bitmap files into arrays of
       characters for printing or including in text files.  The atobm
       program can be used to convert strings back to bitmap format.

USING BITMAPS IN PROGRAMS
       The format of bitmap files is designed to make bitmaps and cursors
       easy to use within X programs.  The following code could be used to
       create a cursor from bitmaps defined in this.cursor and
       this_mask.cursor:

               #include "this.cursor"
               #include "this_mask.cursor"

               XColor foreground, background;
               /* fill in foreground and background color structures */
               Pixmap source = XCreateBitmapFromData (display, drawable,
                       this_bits, this_width, this_height);
               Pixmap mask = XCreateBitmapFromData (display, drawable,
                       this_mask_bits, this_mask_width, this_mask_height);
               Cursor cursor = XCreatePixmapCursor (display, source, mask,
                       foreground, background, this_x_hot, this_y_hot);


       Additional routines are available for reading in bitmap files and
       returning the data in the file, in Bitmap (single-plane Pixmap for
       use with routines that require stipples), or full depth Pixmaps
       (often used for window backgrounds and borders).  Applications
       writers should be careful to understand the difference between
       Bitmaps and Pixmaps so that their programs function correctly on
       color and monochrome displays.

       For backward compatibility, bitmap will also accept X10 format bitmap
       files.  However, when the file is written out again it will be in X11
       format

X DEFAULTS
       Bitmap uses the following resources:

       Background
           The window's background color.  Bits which are 0 in the bitmap
           are displayed in this color.  This option is useful only on color
           displays.  The default value is white.


       BorderColor
           The border color.  This option is useful only on color displays.
           The default value is black.


       BorderWidth
           The border width.  The default value is 2.


       BodyFont
           The text font.  The default value is variable.


       Dashed
           If ``off'', then bitmap will draw the grid lines with solid
           lines.  The default is ``on''.


       Foreground
           The foreground color.  Bits which are 1 in the bitmap are
           displayed in this color.  This option is useful only on color
           displays. The default value is black.


       Highlight
           The highlight color.  bitmap uses this color to show the hot spot
           and to indicate rectangular areas that will be affected by the
           Move Area, Copy Area, Set Area, Clear Area, and Invert Area
           commands.   If a highlight color is not given, then bitmap will
           highlight by inverting.  This option is useful only on color
           displays.


       Mouse
           The pointer (mouse) cursor's color.  This option is useful only
           on color displays.  The default value is black.


       Geometry
           The size and location of the bitmap window.


       Dimensions
           The WIDTHxHEIGHT to use when creating a new bitmap.

SEE ALSO
       X(1), Xlib - C Language X Interface (particularly the section on
       Manipulating Bitmaps), XmuReadBitmapDataFromFile

BUGS
       The old command line arguments aren't consistent with other X
       programs.

       If you move the pointer too fast while holding a pointer button down,
       some squares may be missed.  This is caused by limitations in how
       frequently the X server can sample the pointer location.

       There is no way to write to a file other than the one specified on
       the command line.

       There is no way to change the size of the bitmap once the program has
       started.

       There is no undo command.

COPYRIGHT
       Copyright 1988, Massachusetts Institute of Technology.
       See X(1) for a full statement of rights and permissions.

AUTHOR
       bitmap by Ron Newman, MIT Project Athena; documentation, bmtoa, and
       atobm by Jim Fulton, MIT X Consortium.


Licensed material--property of copyright holder(s)

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026