CD Actual 15/CDACTUAL15.iso/cdactual/program/pascal/SCNDSIGN.ZIP/MDRAW.DOC

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                    MONODRAW User Documentation


                          Frank G. Pagan
                       3206 Kingswood Court
                        Fullerton, CA 92635





                           Introduction


MONODRAW is a simple but useful public domain drawing program for
IBM-compatible personal computers equipped with a Hercules-
compatible monochrome graphics adapter and a high resolution
monochrome monitor.  There are no other special system
requirements.

Monochrome graphics is the most affordable kind of graphics
available on PC and XT class computers and is a very common
feature on these machines.  It is also of very high quality,
providing 720 pixel columns by 348 pixel rows.  All things
considered, it is an excellent graphics system for applications
where color is not needed or wanted.  Unfortunately, it has gone
unsupported by the great majority of public domain software
products and by many low-end commercial products.  MONODRAW should
help to fill this gap.

The program is primarily oriented toward the creation and printing
of line drawings (diagrams) with a limited amount of embedded
text.  On the one hand, it is definitely not an "object-oriented"
CAD program; on the other hand, it lacks some of the more exotic
features of many paint programs.  What it does do is allow you to
set individual pixels, draw and erase lines, rectangles and
elliptical curves, fill areas with various patterns, draw text in
any of five fonts and a wide range of sizes, duplicate parts of a
diagram, save and retrieve diagrams on disk, and print a hard copy
of a diagram.  Even with a dot matrix printer, publication-quality
results can be achieved.

There are a couple of features that distinguish MONODRAW from most
paint programs.  One is that all menu and settings information is
located on a separate screen page, which is nevertheless instantly
accessible at any time.  This frees all 250,560 (= 720 x 348)
pixels for use in the diagram itself.  In keeping with this
philosophy of maximum resolution, the drawing cursor consists of a
single blinking pixel, giving you the finest possible degree of
control over your diagram.



                          Getting Started


The program is contained in the file MDRAW.EXE.  To run it, insert
the disk into the logged drive and type MDRAW at the DOS prompt.
As the title screen warns you, the drawing commands are case
sensitive and you should make sure that your Caps Lock is off.  To
get past the title screen, press any key.  You will then see what
we will call the settings/help screen being created.  The top half
shows the various drawing options, which you can change at any
time, and their current settings.  The bottom half is a quick-
reference summary of the various keypress drawing commands that
you can issue when the drawing screen is displayed.  You press the
Escape key to switch from the settings/help screen to the drawing
screen or vice versa.

To try out some of the basic drawing commands, press Escape to
switch to the drawing screen.  The screen will be blank except for
a single, fast-blinking pixel at the extreme upper left.  This is
the drawing cursor.  To make that pixel stay lit, press the space
bar.  The cursor's position has not changed, but you can't see it
at the moment because it blinks only when it is positioned at an
unlit pixel.  Now hold down a shift key and press the down arrow
key four times.  You will see the cursor move down a distance of
16 pixels at each keystroke.  Release the shift key and press L; a
line is drawn from the original corner position down to the
current cursor position.  The program will now remember the latter
as a "previous" position for another Line command.  To see this,
hold down Shift and press right arrow four times; at each of these
keystrokes, the cursor jumps 32 pixels to the right.  Now when you
press L (unshifted), a horizontal line is drawn from the previous
point to the cursor.  To make a complete triangle, first move the
cursor back to the upper left corner by pressing Shift Home four
times and press the L key again.

You could of course draw a rectangle one side at a time too, but,
for rectangles made of verical and horizontal lines, there is a
much faster way.  First move clear to the right of the triangle by
pressing shift right arrow six times.  Press the space bar to mark
this pixel.  Press shift PgDn four times to move rightwards and
downwards.  Press unshifted B (for "Box") and a rectangle is
drawn, with the previous point as the upper left corner and the
cursor as the bottom right corner.

To draw an ellipse, first move the cursor to the right by pressing
shift right arrow four times.  Mark this pixel using the space
bar; this is the starting point for the ellipse.  Move the cursor
upwards and rightwards by pressing shift PgUp twice.  This is the
first counterclockwise quarter point for the ellipse; i.e., the
program will take the center of the ellipse to be in the same
column as the previous point and in the same row as the cursor.
Press unshifted C ("Curve") and the ellipse will be drawn.

If you want to leave the program for now and get back to DOS,
press the Q key (unshifted).  The long beep you hear is the
program warning you that you have not saved your drawing.  Press Q
again to let it know that you really did mean to Quit
nevertheless.



                   Changing the Current Settings


When you went through the drawing exercise described above, you
were using the default drawing settings.  This meant, for example,
that all lines were solid (not dotted or dashed) and of normal
thickness (1 pixel as opposed to 3), and that all curves were full
ellipses.  You could not add text to your diagram because there is
no default text string, and you could not save it to disk because
there is no default file name.  Whenever you need to set or change
attributes such as these, you make use of the settings/help
screen.  Press Escape, if necessary, to switch to it.

The settings panel has a cursor, consisting of a small solid
square, positioned immediately to the right of the current
heading.  Initially, it marks the top line, which invites you to
press a function key to change a setting or Escape to switch to
the drawing screen.  Pressing one of the ten function keys will
move the cursor to the end of the corresponding setting heading:

        F1. Drawing name
        F2. Line style
        F3. Curve type
        F4. Text font
        F5. Text size
        F6. Text flow direction
        F7. Horizontal text justification
        F8. Vertical text justification
        F9. Fill pattern
       F10. Text string

You must then either press a key in an indicated range (for F2
through F9) or enter a sequence of characters (for F1 or F10) to
change the setting.

For F2 through F9, the current setting is marked by an asterisk at
the left.  When you press a valid digit key (or A or B for F9),
the asterisk will move to mark the new setting, and the cursor
will return to the top line.  For F1, type a valid file name,
possibly beginning with a drive specifier and/or a directory path.
Do not add a file extension; '.DGM' will be added automatically.
The characters will appear under the F1 heading as you type them;
you can use the backspace key to correct mistakes.  Pressing the
Enter key terminates the entry and returns the cursor to the top
line.  An F10 entry works similarly, except that you can type any
string of characters that does not go past the right side of the
screen.

The possible settings for F2 through F9 are described below.  In
each case, the asterisk marks the default setting.  You should
experiment freely with changing a setting, switching to the
drawing screen to see the effect on subsequent drawing actions,
switching back to change another setting, etc.

The LINE STYLE (F2) settings are

      * 0 - Normal solid
        1 - Normal dotted
        2 - Normal dashed
        3 - Thick solid
        4 - Thick dotted
        5 - Thick dashed

Normal lines are 1 pixel thick.  "Thick" lines are 3 pixels thick.

The CURVE TYPE (F3) settings are

      * 0 - Full ellipse
        1 - Half ellipse
        2 - Quarter ellipse

A circle is, of course, a special case of an ellipse.  Half and
quarter ellipses are useful for drawing such things as rounded
ends and corners of objects.

The TEXT FONT (F4) settings are

      * 0 - 8 by 8
        1 - Triplex
        2 - Small
        3 - Sans serif
        4 - Gothic

The default font is the one used in the settings/help screen.  In
the default size, each character occupies an 8 by 8 block of
pixels.  The other fonts employ proportional spacing.

The TEXT SIZE (F5) setting is a number between 0 and 9.  The
default is 0, corresponding to the smallest size.  The actual
effect of this setting on character size depends on what the
current font is.

The TEXT FLOW (F6) settings are

      * 0 - Horizontal
        1 - Vertical

The HORIZ JUSTIFY (F7) settings are

      * 0 - Left
        1 - Center
        2 - Right

Assuming that text flow is horizontal, with setting 0 the text
string will be drawn to the right starting at the cursor position
when a Text command is issued.  With setting 1 it will be drawn
such that the string is centered around the cursor.  With setting
2 it will be drawn such that the string ends at the cursor.

The VERT JUSTIFY (F8) settings are

      * 0 - Bottom
        1 - Center
        2 - Top

Assuming that the text flow is vertical, with setting 0 the text
string will be drawn upwards starting at the cursor position when
a Text command is issued.  With setting 1 it will be drawn such
that the string is centered around the cursor.  With setting 2 it
will be drawn such that the string is below the cursor.

The FILL PATTERN (F9) settings are

        0 - Empty
      * 1 - Solid
        2 - Horizontal lines
        3 - Light slash
        4 - Thick slash
        5 - Thick backslash
        6 - Light backslash
        7 - Hatch
        8 - Heavy cross hatch
        9 - Interleaving lines
        a - Widely spaced dots
        b - Closely spaced dots


In general, whenever you press an inappropriate key, you will hear
a short beep and nothing will change.



                     Moving the Drawing Cursor


In the drawing screen, the cursor is a single pixel, which will be
blinking unless it has been turned on by a drawing command.  You
move the cursor using the eight "motion" keys in the numeric
keypad, either shifted or unshifted.  The direction of movement
corresponds to the position of the key relative to the 5 key.  The
cursor cannot be moved past an edge of the screen.

Left arrow: 1 pixel to the left.
Home: 1 to the left and 1 up.
Up arrow: 1 up.
PgUp: 1 up and 1 to the right.
Right arrow: 1 to the right.
PgDn: 1 to the right and 1 down.
Down arrow: 1 down.
End: 1 down and 1 to the left.
Shift left arrow: 32 pixels to the left.
Shift Home: 32 to the left and 16 up.
Shift up arrow: 16 up.
Shift PgUp: 16 up and 32 to the right.
Shift right arrow: 32 to the right.
Shift PgDn: 32 to the right and 16 down.
Shift down arrow: 16 down.
Shift End: 16 down and 32 to the left.




                       The Drawing Commands


There are 14 keystroke commands you can issue when the drawing
screen is displayed, and they are all explained below.  The Line,
Box, Curve, and Get commands make use of a "previous" pixel
position distinct from the current cursor position.  This previous
position is set by each mark (space bar), Line, Box, and Curve
command to the position of the cursor at the time the command is
issued. No command changes the cursor position itself.

The MODE (m) command toggles between the program's drawing and
erasing modes.  Initially, the program is in the drawing mode.  In
the erasing mode, the cursor blinks at double speed (if it is at
an unlit pixel).  The mark (space bar), Line, Box, and Curve
commands then have the effect of turning off lit pixels.

The MARK (space bar) command sets the current pixel and updates
the "previous" position.

The LINE (l) command draws a straight line from the previous
position to the current position using the current line style and
updates the previous position.

The BOX (b) command, using the current line style, draws a
rectangle with one corner at the previous position and the
diagonally opposite corner at the current position.  The previous
position is updated.

The CURVE (c) command, using the current line style, draws a full,
half, or quarter ellipse using the previous position as the
starting point and the current position as the first
counterclockwise quarter point.  The previous position is updated.

The FILL (F) command fills an enclosed area surrounding the cursor
with the current fill pattern.

The TEXT (t) command draws the current text string in accordance
with the current font, size, flow, and justification settings.
The vertical position of horizontal text is affected by the
vertical justification setting: for bottom justify, the text
appears slightly higher than the cursor; for center justify, it
appears next to the cursor; and for top justify, it appears
slightly lower than the cursor.

The GET (g) command captures a rectangular block of pixels defined
by the previous position and the current position.  You will hear
a short beep if the block is too large.

The PUT (p) command sets a rectangular block of pixels, using the
current position as the upper left corner, to be a duplication of
a block captured by a preceding Get command.

The WRITE (w) command saves the current diagram and current
settings to a disk file n.DGM, where n is the current drawing
name.  If n is not a valid file name, you will hear a short beep.

The INPUT (i) command retrieves a saved diagram and settings from
the disk file n.DGM, where n is the current drawing name.  If the
diagram has not been saved since the last change, you will hear a
long beep.  To confirm that you want to replace the current
drawing with one on disk, repeat the Input command; to abort,
press any other key.  As a reminder that any of the settings could
have been changed by the input operation, the settings/help screen
is flashed momentarily.  If the file is not found, you will hear a
short beep.

The HARDCOPY (H) command sends the diagram to a printer.  This has
nontrivial ramifications.  For further information, read the next
section.

The CLEAR (Alt C) command erases the drawing screen.  If the
diagram has not been saved since the last change, you will hear a
long beep.  To confirm that you want to discard the current
drawing, repeat the Clear command; to abort, press any other key.

The QUIT (q) command terminates the program run.  If the diagram
has not been saved since the last change, you will hear a long
beep.  To confirm that you do not want to save the current
drawing, repeat the Quit command; to abort, press any other key.




                       Printing a Hard Copy


The Hardcopy command actually invokes a completely separate
program assumed to reside in a file PRINTDWG.EXE in the current
directory.  The problem of printing graphics "screen dumps" is
notorious for its dependence on user taste and the characteristics
of different printers.  Accordingly, you are free to acquire any
printing program you like and rename it PRINTDWG.EXE, or even, if
you have the know-how, write your own.

The particular printing program supplied with MONODRAW was written
for an Epson-like dot matrix printer (specifically, a Star
Micronics Gemini 10X).  It prints the diagram on a standard
letter-sized form, rotated 90 degrees to the right so that the
leftmost pixel columns of the diagram are printed as the topmost
dot rows across the sheet.  The aspect ratio of the resulting hard
copy is 12% "flatter" than it is on the screen.  The source code
(in Turbo Pascal version 4.0) for this program is supplied in the
file PRINTDWG.PAS, in case you want to try modifying it to suit
your own taste or your own printer.

When PRINTDWG.EXE is finished printing the hard copy, MONODRAW
retakes control of the computer.  If PRINTDWG.EXE is not found,
you will hear a short beep.




                        Some Helpful Hints


Creating diagrams often involves a lot of erasing and redrawing.
There are several ways of erasing parts of a diagram in MONODRAW.
If you toggle into erase Mode, you can erase individual pixels
with the Mark (space bar) command or entire lines, boxes, and
curves with the L, B, and C commands.  To completely clear a small
area of a diagram, you can move to a blank region, capture a blank
block of pixels with the Get command, move to the area to be
cleared, and issue a Put command.  (If you momentarily use the
erase mode when marking the previous point for the Get, that point
will remain unlit.)  Contiguous groups of lit pixels, such as
those comprising text characters, can be deleted by setting the
fill pattern to empty, toggling to the erase mode, and issuing a
Fill command.

For many diagrams it is a good idea to draw all the text items
first and all the line items later.  Otherwise, it can be hard to
get the text items to fit right.

Before doing a "dangerous" operation such as a Fill, Put or Text
in a complex diagram, you should first do a precautionary Write.
That way, if the operation does not do what you expected, you can
undo it by issuing an Input command.