The World of Computer Software/World_Of_Computer_Software-02-387-Vol-3of3.iso/p/pep13a.zip/CHAPT1.TXT

Text File | 1992-12-17 | 27KB | 467 lines

<Chapter 1:  Introduction>

Copyright (c) 1992 Trionum Inc.  All rights reserved.

TRIONUM and PEP are trademarks of Trionum Inc.  All other brand and
product names are trademarks or registered trademarks of their respective
companies.

<Section 1.1:  What is PEP?>
     The name PEP is an acronym for "Picture Editing Package". PEP is a
drawing program for personal computers. You can use it to create pictures
composed of text and graphics, display these pictures on your computer's
monitor, print them on your printer, and save them in files compatible
with other software packages. All of the illustrations in this manual, for
example, were drawn using PEP.

<Section 1.2:  Getting Started>
     In order to install and use PEP, you will need to be familiar with
the basic commands of the DOS operating system. If you have any questions
about using DOS, consult your operating system manual.

<Section 1.2.1:  Hardware and Software Required>
     In order to run PEP you need an IBM PC, XT, AT, PS-2 or compatible
computer running DOS 2.0 or a later version of DOS. You also need a
graphics display, either the color graphics adapter (CGA), the extended
graphics adapter (EGA), the video graphics array card (VGA), or the
HERCULES card.

     You do not need a floating point processor, a hard disk, or a mouse.
If you have a mouse, you will be able to use it with PEP.

     In order to print directly from PEP, you need one of the following
printers: an Epson printer, an IBM graphics printer, an IBM Color Printer,
a Postscript based printer such as the Apple LaserWriter, an HP LaserJet,
an HP DeskJet, or a printer compatible with one of these. In addition, you
can output pictures from PEP to both PCX files (a popular bitmap format)
<[13.2]> and EPS files (the encapsulated Postscript format) <[16.9]>. Many
word processors and desktop publishing packages accept graphics in these
formats. Pictures that you draw in PEP can be included, in this way, into
documents created by any of these compatible packages. If you are using
Lotus Manuscript or Samna Word, these two word processors will accept
graphics directly from PEP in the original PDL file format.

<Section 1.2.2:  Installation>
     Before you can use PEP, you must install it on your computer. This
means that you must first tell PEP about the hardware configuration that
you have: the type of display, the type of printer, and so forth. The
utility INSTALL.EXE supplied with PEP will guide you through this simple
installation process. Full instructions for installing PEP are provided in
Chapter <[17]>.

<Section 1.2.3:  About this Manual>
     After this introductory chapter, is the main part of the PEP manual,
namely the command descriptions in Chapters <[2]> through <[14]>. In those
chapters, you will find a complete explanation of each of the commands
available in PEP. In this present chapter, we provide the definitions and
background information necessary to understand the chapters that follow.
We strongly recommend that you read this chapter carefully before trying
to use PEP. Then if you need information about a particular command, you
will be ready to turn directly to the relevant section in the reference
chapters.

     Chapter <[15]> describes the HELP system, which allows you to view
this manual, while you are using PEP.

     After you have gained a little experience using PEP, you should look
at Chapter <[16]>, the final chapter in the reference section. That
chapter contains a number of hints and practical suggestions for
approaching various problems. You may find this material helpful when you
begin to apply PEP to real uses.

<Section 1.3:  Menus and Commands>
     PEP commands are organized into a menu hierarchy. The menu that is
displayed when you first load PEP is called the top menu. Certain commands
in this menu cause new menus to be displayed. In some cases, these new
menus also have commands leading to yet other menus, and so forth. Most of
the time, however, you will be operating either in the top menu or in the
menus one level down from the top.

     In each command menu, the first letters of the commands are all
different. To execute a command just type its first letter. Alternatively,
you can highlight a menu item by pointing to it with the cursor. Then, if
you press RETURN (or the left mouse button), the highlighted command will
be executed.

For example, in PEP's top menu, if you type "I" (for "Insert"), a new
menu will appear as shown in <[FIG07]>. This new menu contains all of the
commands for inserting the different kinds of elements. (It contains a
number of other commands as well.) If you now type "L" (for "Line") you
will be ready to insert one or more straight lines.

     Throughout this manual we will name a command by listing the steps to
that command from the top menu. This command for inserting straight lines,
for example, is called the INSERT/LINE command <[2.1]>.

     In addition to the commands in the menus, there are a number of
commands that you can execute at any time regardless of your position in
the menu hierarchy. These commands are executed either by striking a
single key, or by holding down the ALT key and striking a key. In either
case, they are called single keystroke commands. More specifically, these
commands are invoked by pressing a function key, a combination of ALT plus
a function key, or a combination of ALT plus a letter key. Many of these
commands can also be executed within the command menu hierarchy. For
example, the single keystroke command ALT-R turns on and off the display
of rulers. This command performs the same function as the
SETUP/WINDOW/RULER command <[12.2.10]> in the menu hierarchy.

     You should become familiar with three function key commands that are
useful for obtaining information about PEP and your current state within
it. These are described briefly below. For complete information about
these and the other single keystroke commands, see Chapter <[14]>.

     Pressing the help key (F1) activates the HELP system, which gives you
on-line access to the complete PEP manual. The HELP system is described in
Chapter <[15]>.

     Pressing the status key (F2) temporarily replaces the command menu
with current status information.

     Pressing the menu cycle key (F3) temporarily replaces the command
menu with quick reference lists of the single keystroke commands: first, a
list of the function key commands, second, a list of the ALT-function key
commands, and finally a list of the ALT-letter commands. Pressing F3 a
fourth time restores the normal menu display.

<Section 1.4:  Windows>
     The PEP screen is divided into a number of windows: a menu window, a
text window, a button window, and one or more graphics windows. The menu
window is used by PEP to display its commands and status information. The
text window is used for prompts and error messages. The button window
permits fast access to certain PEP functions via the mouse. The graphics
windows are used for displaying and modifying your drawings.

     This subdivision of the screen is based on a system of
non-overlapping areas called tiles. You can configure your screen by
subdividing tiles, deleting tiles, moving tile boundaries, and assigning
roles to tiles. These commands can be found in the SETUP/TILING menu
<[12.1]>. In particular, it is possible to display multiple views of the
open object in multiple screen tiles, each view at a different
magnification. For example, one tile might be used for an overview, and
another for editing in detail.

     One of the graphics tiles is displayed with a bolder boundary to
distinguish it from the others. If you have a color display, the boundary
of this tile will also be a different color, namely cyan, a light blue.
This tile is called the active window. Any graphics tile can be the active
window. You can determine which graphics tile is the active window by
using the SETUP/WINDOW/NEXT (or ALT-N) command <[12.2.1]>.

     Once you have selected the active window, you can then modify its
properties by using the commands in the SETUP/WINDOW menu <[12.2]>. There
are also a number of single keystroke commands for the same purpose. For
example, you can contract the display with the ALT-C command and expand it
with ALT-E. You can shift the display by using shift and the keys of the
numerical keypad (the NumPad keys) as shown in <[FIG17]>.

     Being able to control the active window display is crucial to using
PEP effectively. We strongly recommend that new users, at a minimum,
become familiar with the eight single keystroke commands listed below.
They are described more fully in Chapter <[14]>, and additional
information can be found in the discussion of the SETUP/WINDOW commands in
Chapter <[12]>.

  ALT-C  Contract the active window display
  ALT-E  Expand the active window display
  ALT-R  Display rulers in the active window
  ALT-G  Display the snap grid
  ALT-T  Display the entire object or page
  ALT-U  Put window upper left corner at the cursor
  ALT-V  Display a simplified view of the object
  ALT-W  Re-initialize all active window properties

     The installation utility creates a default screen configuration for
you, which you can then change if you like. <[FIG05]> shows the most
commonly used configuration. However, if you are using a CGA display or
are not using a mouse, your default configuration will be somewhat
different.

<Section 1.5:  Moving the Cursor>
     PEP's default cursor is a small solid box. Several other forms of
cursor are also used: crosshairs, lines, and boxes of different types. The
shape of the cursor depends on the operation you are performing. There are
several ways to move the cursor in PEP. These are described below.

<Section 1.5.1:  Mouse>
     If you have a mouse, you can move the cursor by simply moving the
mouse.

<Section 1.5.2:  Cursor Motion Keys>
     Eight NumPad keys can be used to move the cursor. The arrow keys move
the cursor in the direction of the arrow. The corner keys (Home, PgUp,
PgDn, and End) move the cursor diagonally (up-left, up-right, down-right,
and down-left, respectively). See <[FIG08]>. These eight keys are called
the cursor motion keys.

     How far the cursor moves with each keystroke is determined by the
SETUP/SYSTEM/STEP command <[12.3.1]> (or the Grey-minus key). This command
cycles through three modes: a single pixel mode and two multiple pixel
modes: full-step and half-step. In single pixel mode, each keystroke moves
the cursor one pixel on the screen. In the multiple modes, each stroke
moves the cursor one multiple-pixel step. The default step size is 10
pixels (5 pixels for a half step). You can change the size of the cursor
step with the SETUP/NUMBERS/STEP-SIZE command <[12.4.1]>.

<Section 1.5.3:  Automatic Motion>
     If you need to move the cursor over a large distance, using the
cursor motion keys can be tedious. If you do not have a mouse, you may
want to use the automatic cursor motion capability. You can start the
cursor moving, accelerate it, change its direction, and stop the motion
when the cursor arrives at its destination.

     To start the cursor moving, press the Grey-plus key, and then press
one of the cursor motion keys. The cursor will begin to move at a constant
speed in the direction indicated by the motion key. To make the cursor
move faster, press the same key again. To change direction, press a
different cursor motion key. To stop the cursor, press the Grey-plus key a
second time.

<Section 1.5.4:  Grid Snapping>
     PEP provides a snap grid capability to assist you in aligning picture
elements with one another. You can control the horizontal and vertical
spacing of the grid points by using the SETUP/NUMBERS/GRID-SPACE command
<[12.4.2]>. You can make the grid visible in the active window by using
the SETUP/WINDOW/GRID command <[12.2.9]> (or ALT-G). At any time, you can
press the function key F8 to move the cursor from its current position to
the nearest grid point. This is called manual snapping. By using the
SETUP/SYSTEM/GRID command <[12.3.2]> (or ALT-S), you can turn on automatic
snapping. When snapping is on, if you insert, move, or duplicate an
element using the cursor, the element will be positioned on the grid, not
at the cursor position, but at the grid point nearest to it. The snapping
options are available whether or not the grid is visible.

<Section 1.5.5:  Stretchable Box Cursors>
     In PEP, the cursors appear in a variety of forms: cross-hairs,
horizontal and vertical hairlines, and rigid and stretchable boxes. In the
case of stretchable boxes, which are used, for example, during editing to
stretch a picture element, one corner of the box is mobilized at any given
time. This corner can be moved by any of the methods just described. The
mobile corner is distinguished by a small solid box marker. To change the
mobile corner, press SPACE or the Grey-star key. The next corner
counterclockwise is mobilized. <[FIG13]>.

<Section 1.6:  Objects and Picture Files>
     PEP stores pictures in files called picture files. These files have
the extension PDL, which stands for "Picture Description Language". To
display, print, or modify the pictures in a picture file, you must first
load that file into your computer's memory by using the FILE/LOAD command
<[8.2]>. That file then becomes the loaded picture file.

     A PDL file might contain only one picture, but often it will contain
more than one. Each file is actually a library of pictures, and each
picture has its own name. A picture in a PDL file is called an object. To
display, print, or modify an object, you must first select it using the
OBJECT/OPEN command <[7.1]>. This displays the object on your screen,
ready to be edited. We will refer to it as the open object.

     If you modify the open object, and want to save the changes to disk,
this also is a two step process. First you close the open object using the
OBJECT/CLOSE command <[7.2]>; then you save the file containing that
object to disk using the FILE/SAVE command <[8.3]>.

     The basic units that make up objects are called elements. The
elements of an object can be lines, arcs, text, filled regions, groups of
elements, and other objects.

     Each object in a file is assigned an object name. The objects in a
file may be independent of one another, or they may be interrelated, some
objects being used as elements inside of others. In this case, we may
refer to these elements as sub-objects of the objects in which they
appear. These sub-objects may contain yet other objects. Objects may be
nested to any depth.

     In summary, a typical editing session consists of loading a picture
file from disk, opening an object for editing, modifying the open object
(via insert, delete, and modify commands), printing the result, closing
the open object, and saving the file back to disk.

<Section 1.7:  Coordinates>
     Objects drawn in PEP are defined in a coordinate system that is
independent of any output device. When the picture is printed or
displayed, its size is determined by a pair of stretch factors. There is a
horizontal stretch and a vertical stretch. If the stretches are both 1
when the object is drawn, each point in the object is represented by
exactly one pixel on the printer or the display. If the stretches are
increased, the size of the object's image is made larger; if they are
decreased, the image is made smaller. If you are printing, the object may
also be rotated or drawn in mirror image.

     When we speak of object coordinates, we mean the device independent
coordinates in which the object is defined. A pair (X,Y) of object
coordinates defines the position of a single point in the object before
stretches and rotations have applied. This happens in the following way.
The X coordinate determines the horizontal position of the point. X equals
0 for points on the left edge of the object and X increases for points
farther to the right. The Y coordinate determines the vertical position of
a point. Y equals 0 for points at the top edge of the object, and Y
increases for points farther down. The coordinates (0,0) represent the
upper left corner. <[FIG12]>.

     You can, if you wish, always leave the printer stretches at their
default values of 1. (This is what we recommend for most purposes anyway.)
In this case, just think of the object coordinates as representing the
locations of the individual pixels on the printed page.

<Section 1.8:  More about Menus and Commands>
     The menus in PEP have a dual role. Primarily, they are lists of
commands, but many menus also display status information. These two
functions interact to produce commands of different types. These are
described below. In some cases a single command plus associated status
display requires more than one line in the menu. In these cases, the extra
lines are indented to distinguish them from command names.

     <[FIG03]> shows a typical PEP menu. This one is the MODIFY/LINE-STYLE
menu <[4.18]>. There are four commands (NIBTYPE, PENSIZE, DASHES, and
QUIT), and six status data items. In this example, the status information
contained in the menu reports the following facts: the current line is
drawn with a pen whose shape is an ellipse, the pen size is 4 pixels wide
and 2 pixels deep, the line is dashed, and the dashing pattern is 1 dot on
for every 8 dots off. The PEP commands are explained one by one in the
chapters that follow. To better understand the meaning of any particular
command and its status items, consult the section devoted to that command
in the appropriate chapter.

<Section 1.8.1:  Name Menus>
     A second kind of menu is used when you are selecting from a list of
names. For example, when loading a picture file, you are presented with a
menu of all files in the current directory with the appropriate extension.
In such a case, the first letters of the menu entries are usually not all
different, so a slightly different method is used when choosing a item
from a name menu. The items listed in a name menu are displayed
alphabetically. The menu appears with an initial item highlighted. As you
begin to type a name, at each keystroke the highlight moves to the first
entry compatible with the keys typed so far. At any point, you can select
the highlighted entry by pressing RETURN. The highlight can also be moved
with the Up-Arrow, Down-Arrow, Home, and End keys. If the list of names is
too large to fit in the menu window at one time, you can use Left-Arrow
and Right-Arrow, or PgUp and PgDn to move the highlight into successive
menu pages. Also, you can highlight an item by simply pointing to it with
the cursor.

<Section 1.8.2:  Moving Up The Menu Hierarchy>
     There are three ways to move up the menu hierarchy. Most menus
include an explicit QUIT command; when you type Q (for QUIT), you are
taken back to the previous menu, the next higher menu in the hierarchy.
The second method is to use the super-escape key (Function key F10).
Pressing this key takes you in a single step to the top level menu no
matter where you are in the command structure. Finally, you can use the
Escape key (ESC). Pressing this key takes you back one step in the command
execution. Often, ESC is equivalent to QUIT, taking you back to the prior
menu. Sometimes, however, it takes you back to an earlier stage in the
same menu. For example, when you insert a line, you first choose a start
point and then choose an end point. If you are at the second stage
(choosing the end point), pressing ESC takes you back to the first stage
(choosing the start point). In any case, if you continue to press ESC, you
eventually return to the prior menu and ultimately to the top level menu.
If you have a mouse, pressing the right mouse button is equivalent to
using the ESC key.

<Section 1.8.3:  Multiple Choice Commands>
     Some menu commands select a value from a small list of options. These
multiple choice commands also display the currently selected value in the
menu. The data is displayed either on the same line as the command name or
on the following line in the menu. When you press the command letter, the
next option in sequence is selected and displayed. Press the command
letter repeatedly to cycle through the complete set of options until the
desired choice appears in the menu.

     <[FIG24]> shows the SETUP/SYSTEM menu <[12.3]> and illustrates the
operation of the SETUP/SYSTEM/GRID command <[12.3.2]>. This command
enables and disables automatic grid snapping, a feature that assists in
the positioning of newly inserted elements. If grid snapping is OFF, then
pressing G (for GRID) in the SETUP/SYSTEM menu turns snapping ON. If
snapping is ON, pressing G turns it OFF. The menu shows the current state.
This is a typical example of a multiple choice command.

<Section 1.8.4:  Entering Names>
     Some menu commands require you to type in a name as an argument. For
example, FILE/SAVE <[8.3]> requires a file name. These are called string
input commands. For these commands, when you press the command letter, a
highlight appears in the menu. The highlighted area may have a default
string already displayed in it; to choose this default simply press
RETURN. Alternatively, you can type in a new name into the highlighted
area. End the string by pressing RETURN. While typing into the echo area,
you can correct mistakes by using the backspace key (delete last
character) and ESC (delete entire string). Press ESC a second time to
abort the command.

<Section 1.8.5:  Entering Numbers>
     XY input commands are similar to string input commands. These
commands require two numerical arguments. For example, PRINT/MARGINS
<[6.10]> needs two arguments for the left (X) and top (Y) margins
respectively. For such a command the following two lines of the menu
display the current status of these arguments. When you press the command
letter, these two lines change: they now begin with X= and Y=
respectively. This is to indicate that X and Y have become valid command
letters. To change the X value, press X to highlight the X line. Type the
desired value exactly as described under string input commands. Similarly,
press Y to start input for the Y argument. <[FIG04]> shows the
MODIFY/LINE-STYLE menu <[4.18]> as it looks after you have pressed P (for
PENSIZE) to enable input of the width (X) and depth (Y) of the current
pen.

     A few XY input commands ask for stretch factors. For example,
SETUP/WINDOW/STRETCHES <[12.2.12]> lets you set the magnification of the
active graphics window display. The smallest possible stretch is 1/256;
the largest is 255. You can type in an integer (e.g. 2), a fraction (e.g.
3/4), or a decimal (e.g. 2.75).

     The remaining XY input commands (the majority) ask for integer
values. The legal range for arguments varies from command to command. You
can type an integer directly, or you can enter a value in physical units:
inches, centimeters, or points (a point is 1/72 of an inch). To enter a
value in inches, add the letter "i" to the end of the input string. To
enter a value in centimeters, add "c". To enter a value in points, add
"p". As before, you can type an integer, a fraction or a decimal. For
example, the following are legal input strings for numbers: 33 (thirty
three abstract pixels or object coordinates), 3/4i (three fourths of an
inch), 2.5c (two and one half centimeters). If you ask for inches,
centimeters, or points your input is converted into object coordinates by
applying the current dots-per-inch value in the X or Y direction as
appropriate. This value defaults to your current printer density, but it
can be changed by using the SETUP/NUMBERS/INCH command <[12.4.5]>.

     In a similar way, you can specify a multiple of the current cursor
step size or the current snap grid interval by adding the letter "s" or
"g" to an integer, fraction or decimal number. You can view and change the
current value of the step size and grid interval by using the
SETUP/NUMBERS/STEP-SIZE <[12.4.1]> and SETUP/NUMBERS/GRID-SPACE commands
<[12.4.2]>.

     If you type in a number in any of these ways, the new value that you
enter replaces the old X or Y value as formerly displayed in the menu.
However, if the string that you enter begins with a plus sign or a minus
sign, then the new value is added to, or subtracted from the former value.
This is relative XY input.

     As an illustration, if you want to move an element to the right by
one half of an inch, use the MODIFY/MOVE command <[4.1]>, press X to
enable X coordinate input, and enter the string "+1/2i". The number of
pixels in one half of an inch will then be added to the current X position
of the element, moving it to the right as required.

     A few XY input commands allow you to enter four numbers rather than
just two. For example, the PRINT/WINDOW command <[6.12]> lets you print a
rectangular piece of the open object instead of printing the entire
object. To specify the window, you need to enter four coordinates, the
left, top, right, and bottom of the window. For these XY input commands,
typing the command letter once enables XY input in the first of two XY
coordinate pairs; typing the command letter a second time enables input
into the second pair.

<Section 1.9:  More about the Mouse>
     PEP has been designed so that you can use a mouse if you have one,
but a mouse is by no means necessary. Every PEP function can be accessed
directly from the keyboard. Cursor motion, in particular, can be
controlled from the keyboard in a number of ways which have been described
above.

     If you do have a mouse, pressing a mouse button is equivalent to
pressing one key on the keyboard. Pressing the left mouse button is
equivalent to pressing RETURN (carriage return). Pressing the right mouse
button is equivalent to pressing ESC (the escape key). Pressing the middle
mouse button (if your mouse has a middle button) is equivalent to pressing
SPACE (the space bar). In the discussion below, we use the key names
RETURN, ESC, and SPACE without explicitly mentioning the mouse. In each
case you can use the equivalent mouse button instead. <[FIG06]>.