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From: <sta...@us...> - 2008-06-21 11:00:41
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Revision: 31524
http://brlcad.svn.sourceforge.net/brlcad/?rev=31524&view=rev
Author: starseeker
Date: 2008-06-20 18:15:56 -0700 (Fri, 20 Jun 2008)
Log Message:
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VolII in docbook is already in better shape - remove this one
Modified Paths:
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brlcad/trunk/doc/book/Makefile.am
Removed Paths:
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brlcad/trunk/doc/book/VolumeII.xml
Modified: brlcad/trunk/doc/book/Makefile.am
===================================================================
--- brlcad/trunk/doc/book/Makefile.am 2008-06-20 21:49:38 UTC (rev 31523)
+++ brlcad/trunk/doc/book/Makefile.am 2008-06-21 01:15:56 UTC (rev 31524)
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documentationdir = $(BRLCAD_DATA)/doc/book
documentation_DATA = \
- VolumeII.xml \
VolumeIV.xml
EXTRA_DIST = $(documentation_DATA)
Deleted: brlcad/trunk/doc/book/VolumeII.xml
===================================================================
--- brlcad/trunk/doc/book/VolumeII.xml 2008-06-20 21:49:38 UTC (rev 31523)
+++ brlcad/trunk/doc/book/VolumeII.xml 2008-06-21 01:15:56 UTC (rev 31524)
@@ -1,7842 +0,0 @@
-<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
-"/Users/cyapp/tmp/xml-dtd-4.4/docbookx.dtd">
-
-<book>
- <bookinfo>
- <title>BRL-CAD Tutorial Series: Volume II - Introduction to MGED</title>
- <authorgroup>
- <author>
- <firstname>Lee</firstname>
- <surname>Butler</surname>
- <othername role='mi'>A</othername>
- <affiliation>
- <shortaffil>ARL</shortaffil>
- <orgname>Army Research Laboratory</orgname>
- <orgdiv>Survivability/Lethality Analysis Directorate</orgdiv>
- <address>
- Aberdeen Proving Ground
- <state>MD</state>
- <postcode>21005-5068</postcode>
- </address>
- </affiliation>
- </author>
- <author>
- <firstname>Eric</firstname>
- <surname>Edwards</surname>
- <othername role='mi'>W</othername>
- <affiliation>
- <shortaffil>SURVICE</shortaffil>
- <orgname>SURVICE Engineering Company</orgname>
- <address>
- <street>4695 Millennium Drive</street>
- <city>Belcamp</city>
- <state>MD</state>
- <postcode>21017-1505</postcode>
- </address>
- </affiliation>
- </author>
- <author>
- <firstname>Betty</firstname>
- <surname>Schueler</surname>
- <othername role='mi'>J</othername>
- <affiliation>
- <shortaffil>QRI</shortaffil>
- <orgname>Quantum Research International, Inc.</orgname>
- <address>
- <street>2014 Tollgate Rd, Suite 203</street>
- <city>Bel Air</city>
- <state>MD</state>
- <postcode>21014</postcode>
- </address>
- </affiliation>
- </author>
- <author>
- <firstname>Robert</firstname>
- <surname>Parker</surname>
- <othername role='mi'>G</othername>
- <affiliation>
- <shortaffil>ARL</shortaffil>
- <orgname>Army Research Laboratory</orgname>
- <orgdiv>Survivability/Lethality Analysis Directorate</orgdiv>
- <address>
- Aberdeen Proving Ground
- <state>MD</state>
- <postcode>21005-5068</postcode>
- </address>
- </affiliation>
- </author>
- <author>
- <firstname>John</firstname>
- <surname>Anderson</surname>
- <othername role='mi'>R</othername>
- <affiliation>
- <shortaffil>ARL</shortaffil>
- <orgname>Army Research Laboratory</orgname>
- <orgdiv>Survivability/Lethality Analysis Directorate</orgdiv>
- <address>
- Aberdeen Proving Ground
- <state>MD</state>
- <postcode>21005-5068</postcode>
- </address>
- </affiliation>
- </author>
- </authorgroup>
-
- <publishername>Army Research Laboratory</publishername>
- <pubsnumber>ARL-SR-102</pubsnumber>
- <pubdate>April 2001</pubdate>
-
- <legalnotice>
- <para>Approved for public release; distribution is unlimited</para>
-
- <para>The findings in this report are not to be construed as an
- official Department of the Army position unless so designated
- by other authorized documents.</para>
-
- <para>Citation of manufacturer's or trade names does not constitute
- an official endorsement or approval of the use thereof.</para>
-
- <para>Destroy this report when it is no longer needed. Do not return
- it to the originator.</para>
- </legalnotice>
-
- <abstract>
- <para>
- Since 1979, the U.S. Army Research Laboratory has been developing and
- distributing the BRL-CAD constructive solid geometry (CSG) modeling
- package for a wide range of military and industrial applications. The
- package includes a large collection of tools and utilities including an
- interactive geometry editor, ray-tracing and generic framebuffer
- libraries, a network-distributed image-processing and signal-processing
- capability, and an embedded scripting language.
- </para>
-
- <para>
- As part of this effort, a multivolume tutorial series is being developed
- to assist users in the many features of the BRL-CAD package. The
- "Introduction to MGED," which is the second volume in the series, is
- intended to provide new users with a basic understanding of the
- Multi-Device Geometry Editor (MGED), which is the heart of BRL-CAD. Other
- volumes focus on installation procedures, advanced features, and
- programming.
- </para>
- </abstract>
- </bookinfo>
-
- <preface>
- <title>Preface</title>
- <para>
- Since 1979, the U.S. Army Research Laboratory (formerly the Ballistic
- Research Laboratory) has been developing the BRL-CAD constructive solid
- geometry (CSG) modeling package for a wide range of military and
- industrial applications. The strength of the package lies in its ability
- to build realistic models of complex objects from a relatively small set
- of "primitive shapes" by employing the basic Boolean operations of union,
- subtraction, and intersection and by assigning real-world material
- attributes.
- </para>
-
- <para>
- The package comprises a large collection of tools, utilities, and
- libraries including an interactive geometry editor, ray-tracing and
- generic framebuffer libraries, a network-distributed image-processing and
- signal-processing capability, and an embedded scripting language.
- </para>
-
- <para>
- Although BRL-CAD has continued to mature in performance and utility,
- developers have strived to keep the package approachable and easy to use,
- as evidenced by the package's dual command formats, its newly renovated
- graphical user interface (GUI), and its customization potential through
- user scripting.
- </para>
-
- <para>
- In addition, a multivolume tutorial series is being developed to assist
- users in a variety of BRL-CAD areas and applications. The "Introduction to
- MGED," which is the second volume in the series, is intended to provide
- new users with a basic understanding of the Multi-Device Geometry Editor
- (MGED), which is the heart of the BRL-CAD package. Other volumes focus on
- installation procedures, advanced features, and programming.
- </para>
- </preface>
-
- <preface>
- <title>Acknowledgements</title>
- <para>
- The authors would like to thank Paul Tanenbaum, TraNese Christy, Sean
- Morrison, and the other members of the Advanced Computer Systems Team who
- reviewed this document in a timely manner and made many helpful
- suggestions to improve its accuracy and presentation.
- </para>
-
- <para>
- In addition, the authors would like to acknowledge team member Mike Muuss,
- who passed away while this volume was in preparation. Mike was the
- original architect of the BRL-CAD package and guided its development for
- 20 years until his death on 20 November 2000. He embodied a unique blend
- of unparalleled intellect, unquenchable curiosity, and unending energy to
- advance the capabilities of everything and everyone he touched. A
- natural-born troubleshooter, Mike approached every job, big or small, with
- a passion for excellence and a child-like enthusiasm, which helped drive
- BRL-CAD far beyond expectations.
- </para>
-
- <para>
- Although he never got a chance to review this document, much of this work
- is a result of his vision and attention to detail. Therefore, the BRL-CAD
- Tutorial Series is dedicated to his memory. His sharp mind, his warm
- spirit, and his loyal friendship will be greatly missed.
- </para>
- </preface>
-
- <chapter id="Lesson-1">
- <title>Creating Primitive Shapes</title>
-
- <para>
- In this lesson, you will:
-
- <itemizedlist mark='bullet'>
- <listitem>
- <para>Launch the MGED program.</para>
- </listitem>
- <listitem>
- <para>Enter commands at the MGED prompt in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Use the MGED Graphical User Interface (GUI).</para>
- </listitem>
- <listitem>
- <para>Open or create a new database when launching MGED.</para>
- </listitem>
- <listitem>
- <para>Use the GUI to open or create a new database.</para>
- </listitem>
- <listitem>
- <para>Title a database.</para>
- </listitem>
- <listitem>
- <para>Select a unit of length for your design.</para>
- </listitem>
- <listitem>
- <para>Select a primitive shape.</para>
- </listitem>
- <listitem>
- <para>Create a primitive shape using the make command.</para>
- </listitem>
- <listitem>
- <para>Use the Z command to clear the Graphics Window.</para>
- </listitem>
- <listitem>
- <para>Draw a previously created shape using the draw command.</para>
- </listitem>
- <listitem>
- <para>Use the erase command to delete an item in the Graphics Window display.</para>
- </listitem>
- <listitem>
- <para>Create a sphere using the GUI menu.</para>
- </listitem>
- <listitem>
- <para>Use the l command to list a shape's attributes or parameters.</para>
- </listitem>
- <listitem>
- <para>Use the ls command to list the contents of the database.</para>
- </listitem>
- <listitem>
- <para>Eliminate a shape or object from the database using the kill command.</para>
- </listitem>
- <listitem>
- <para>Edit a command.</para>
- </listitem>
- <listitem>
- <para>Use the q or exit commands to quit the program.</para>
- </listitem>
- </itemizedlist>
- </para>
-
- <sect1>
- <title>Launching the MGED Program</title>
-
- <para>
- To launch the MGED program, type mged at the Terminal (tty) prompt and
- then press the ENTER key. This brings up two main windows: the MGED
- Command Window and the MGED Graphics Window (sometimes called the Geometry
- Window). Both windows will initially be blank, awaiting input from you. To
- leave the program at any time, at the Command Line type either the letter
- q or the word quit and then press the ENTER key.
- </para>
-
-
- </sect1>
- <sect1>
- <title>Entering Commands in the Command Window</title>
-
- <para>
- You can type in commands at the mged> prompt. Many experienced UNIX users
- prefer this method because it allows them to quickly create a model (which
- we sometimes refer to as a "design") without having to point and click on
- a lot of options. The complete listing of editing commands and what they
- do can be found in Appendix A.
- </para>
-
- <caution>
- <para>
- Check all typed entries before you press the ENTER key. If you find
- you made a mistake, simply press the BACKSPACE key until you have
- erased over the mistake and then re-type the information. Later you
- will get more experience editing text using vi and emacs command
- emulation.
- </para>
- </caution>
-
- </sect1>
-
- <sect1>
- <title>Using the GUI</title>
-
- <para>
- Users who are more familiar with Microsoft Windows may prefer to use the
- GUI pull-down menus at the top of the Command or Graphics Window (they are
- the same in either window). The menus are divided into logical groupings
- to help you navigate through the MGED program.
- </para>
-
- <para>
- Before you can create a model, you need to open a new database either
- through the Terminal Window when starting MGED or through the GUI after
- starting MGED.
- </para>
- </sect1>
-
- <sect1>
- <title>Opening or Creating a New Database when Launching MGED</title>
-
- <para>
- When launching MGED, you can open or create a database at the same time.
- At the shell prompt (usually a $ or %), in the Terminal Window, type mged
- followed by a new or existing database name with a .g extension. For
- example:
-
- <command>mged sphere.g[ENTER]</command>
-
- <figure>
- <title>Terminal Window</title>
- <screenshot>
- <graphic fileref="terminal.png"></graphic>
- </screenshot>
- </figure>
-
- If you are creating a new database, a small dialog box asking if you want
- to create a new database named sphere.g will appear. Click on Yes, and a
- new database will be created. If sphere.g already exists, MGED will open
- the sphere.g database as the program is launched.
- </para>
- </sect1>
-
- <sect1>
- <title>Using the GUI to Open or Create a Database</title>
-
- <para>
- Alternatively, once you have launched MGED, you can open an existing
- database or create a new database using the GUI menus (at the top of the
- Command or Graphics Window) by clicking on File and then either Open or
- New. Both options bring up a small dialog box. The Open dialog box will
- ask you to type in the name of an existing database. The New dialog box
- will ask you to type in the name of a new database. Click on OK to accept
- the database.
- </para>
-
- <para>
- For this lesson, create a new database called sphere.g. To do this, type
- sphere.g at the end of the path name, as shown in the following
- illustration. Click on OK to accept the database name.
-
- <figure>
- <title>MGED Command Window with Database Dialog Box</title>
- <screenshot>
- <graphic fileref="commandwindow.png"></graphic>
- </screenshot>
- </figure>
-
- <figure>
- <title>MGED Graphics Window</title>
- <screenshot>
- <graphic fileref="graphicswindow.png"></graphic>
- </screenshot>
- </figure>
-
- One advantage to using the GUI, if you aren't familiar with UNIX file
- management, is that this will show you your current path name, so you will
- know exactly where your database is going to be located. This can be
- especially helpful if you have a lot of directories or files to manage.
- </para>
- </sect1>
-
- <sect1>
- <title>Assigning a Title to Your Database</title>
-
- <para>
- You can title your new database to provide an audit trail for you or
- others who might use your database. After the prompt, in the Command
- Window, type title followed by a space and a name that reflects the
- database you are going to make. When you are done, press the ENTER key.
- For example:
-
- <command>mged> title MySphere[ENTER]</command>
-
- Note that in BRL-CAD versions prior to release 6.0, the title is limited
- to 72 characters.
- </para>
- </sect1>
-
- <sect1>
- <title>Selecting a Unit of Length</title>
-
- <para>
- MGED uses millimeters for all internal mathematical processes; however,
- you can create your design using some other unit, such as feet. For this
- lesson, inches is used. To select inches, move your mouse pointer to the
- File menu at the top of the Command Window. Click on File and then
- Preferences. A new menu will appear. Select Units and then Inches. If you
- are not a "point-and-click" type of person and prefer a Command Line, then
- just type units in after the MGED prompt in the Command Window, followed
- by the ENTER key. The Command Line looks like:
-
- <command>mged> units in[ENTER]</command>
- </para>
- </sect1>
-
- <sect1>
- <title>Selecting a Primitive Shape</title>
-
- <para>
- MGED provides a variety of primitive shapes (sometimes referred to as
- simply shapes or primitives) that you can use to build models. Each type
- of shape has parameters that define its position, orientation, and size. A
- listing of these shapes and their respective parameters is given in
- Appendix C.
- </para>
-
- <note>
- <para>
- Historically, the word solid was used for what we now refer to as a
- primitive shape. This older terminology was sometimes difficult for
- new users to understand. If you see the word solid used in any
- BRL-CAD programs, documentation, or commands (e.g., in Appendix A),
- think primitive shape.
- </para>
- </note>
- </sect1>
-
- <sect1>
- <title>Creating a Sphere from the Command Line</title>
-
- <para>
- For this lesson, you are going to create a single sphere. There are two
- ways you can create a primitive shape. You can create all shapes through
- the Command Window and most shapes through the GUI.
- </para>
-
- <para>
- You can easily create a sphere from the prompt in the Command Window by
- typing just a few commands. At the MGED prompt, type:
-
- <command>make sph1.s sph[ENTER] [Note: Use the digit 1, not the letter l] </command>
-
- </para>
-
- <para>
- This command tells the MGED program to:
-
- <informaltable frame="all">
- <tgroup cols='3'>
- <tbody>
- <row><entry>make</entry><entry>sph1.s</entry><entry>sph</entry></row>
- <row><entry>Make a primitive shape</entry><entry>Name it sph1.s</entry>
- <entry>Make the shape a sphere</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- </para>
-
- <para>
- A default sphere will be created, and a wireframe representation of the
- primitive shape will appear in the Graphics Window. In Lesson 4, you will
- give your sphere a solid, three-dimensional look.
- </para>
-
- <para>
- This command will draw the primitive shape in the Graphics Window.
- </para>
- </sect1>
-
- <sect1>
- <title>Clearing the Graphics Window</title>
-
- <para>
- To build another object or work on another primitive shape, you can easily
- clear the Graphics Window through the Command Window. At the Command Line
- prompt, type an uppercase Z (for zap) followed by ENTER.
- </para>
-
- <note>
- <para>
- Before using the zap option, make sure you "activate" (i.e.,
- set the focus on) the Command Window. If you type a z and your cursor
- is still in the Graphics Window, you will send your design spinning.
- Typing a zero (0) will stop the spin.
- </para>
- </note>
- </sect1>
-
- <sect1>
- <title>Drawing a Previously Created Object</title>
-
- <para>
- To recall the sphere, type the command on the Command Line as follows:
-
- <command>draw sph1.s[ENTER]</command>
-
- This command tells the MGED program to:
-
- <informaltable frame="all">
- <tgroup cols='2'>
- <tbody>
- <row><entry>draw</entry><entry>sph1.s</entry></row>
- <row><entry>Draw a previously created primitive shape</entry>
- <entry>named sph1.s</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- </para>
- </sect1>
-
- <sect1>
- <title>Erasing an Item from the Graphics Window</title>
-
- <para>
- You may occasionally want to erase a particular item from the display in
- the Graphics Window. You can use the erase command to remove the item
- without any file operation being performed; the item remains in the
- database. To delete the sph1.s object from the display, at the Command
- Window prompt, type:
-
- <command>erase sph1.s[ENTER]</command>
- </para>
- </sect1>
-
- <sect1>
- <title>Creating a Sphere Using the GUI</title>
-
- <para>
- Another way to create a sphere is to use the GUI menu system duplicated at
- the top of the Command and Graphics windows. Clear your Graphics Window by
- using the previously described Z command. Then, in the Graphics Window,
- click on Create, and a drop-down menu will appear with the various
- primitive shape types available. Select sph (for sphere) under the
- Ellipsoids category. This will bring up a dialog box. Click in the empty
- text box and type sph2.s. Click on Apply or press ENTER. A new sphere
- will be created and drawn in the Graphics Window. When you create a shape
- through the GUI, the shape will automatically be in edit mode so that you
- can change it as needed, and the shape's parameters-which define its
- position, orientation, and size-will be in view.
- </para>
- </sect1>
-
- <sect1>
- <title>Viewing a Shape's Parameters</title>
-
- <para>
- Sometimes when you are making a model, you might want to view a shape's
- parameters, such as height, width, or radius, in the Command Window. You
- can easily list the attributes of a shape by typing the l (for "list")
- command at the Command Window prompt as follows:
-
- <command>l shape_name[ENTER]</command>
- <note><para>[Note: The command is the lowercase letter l]</para></note>
- </para>
-
- <note>
- <para>
- Note: If you attempt to type in the Command Window and you see no
- words appearing there, chances are the focus has not been set on that
- window (i.e., keyboard input is still directed to another window).
- Depending on your system's configurations, the focus is set to a
- window either by moving the cursor into the window or clicking on the
- window.
- </para>
- </note>
-
- <para>
- An example of the dialog that might occur in the Command Window for the
- parameters or attributes of the first sphere you created is as follows:
-
- <literallayout>
- mged> l sph1.s
-
- sph1.s: ellipsoid (ELL)
-
- V (1, 1, 1)
-
- A (1, 0, 0) mag=1
-
- B (0, 1, 0) mag=1
-
- C (0, 0, 1) mag=1
-
- A direction cosines=(0, 90, 90)
-
- A rotation angle=0, fallback angle=0
-
- B direction cosines=(90, 0, 90)
-
- B rotation angle=90 fallback angle=0
-
- C direction cosines=(90, 90, 0)
-
- C rotation angle=0, fallback angle=90
- </literallayout>
- </para>
-
- <para>
- Don't be concerned if you notice in the preceding output that MGED stores
- your sphere as an ellipsoid. In actuality, the sphere is just a special
- case of the ellipsoid (see Appendix C). Also, note that it is not
- important if the numbers in your output do not match what is shown in this
- example.
- </para>
-
- <para>
- Use the l command to list both sph1.s and sph2.s before continuing with
- this lesson.
- </para>
-
- </sect1>
-
- <sect1>
- <title>Listing the Contents of a Database</title>
-
- <para>
- In addition to viewing a shape's contents, you might also want to list the
- contents of the database to see what items have been created. To view the
- database contents, type at the Command Window prompt:
-
- <command>ls[ENTER]</command>
- </para>
- </sect1>
-
- <sect1>
- <title>Killing a Shape or Object</title>
-
- <para>
- Sometimes when creating a model, you may need to eliminate a shape or
- object from the database. The kill command is used to do this. For
- example, if you wanted to kill the sph1.s shape, you would type at the
- Command Window prompt:
-
- <command>kill sph1.s[ENTER]</command>
-
- Make another sphere through either the Command Window or the GUI and name
- it sph3.s. Once the sphere is made, use the kill command to eliminate it
- from the database by typing at the Command Window prompt:
-
- <command>kill sph3.s[ENTER]</command>
-
- You can tell the shape has been eliminated by using the ls command in the
- Command Window to list the contents of the database. At the Command Window
- prompt, type:
-
- <command>ls[ENTER]</command>
-
- You should see two shapes listed: sph1.s and sph2.s.
- </para>
-
- <note>
- <para>
- Note: All changes are immediately applied to the database, so there
- is no "save" or "save as" command. Likewise, there is presently no
- "undo" command to bring back what you have deleted, so be sure you
- really want to permanently delete data before using the kill command.
- </para>
- </note>
- </sect1>
-
- <sect1>
- <title>Editing Commands in the Command Window</title>
-
- <para>
- Occasionally, when you enter commands in the Command Window, you will make
- a mistake in typing. MGED can emulate either the emacs or vi syntax for
- Command Line editing. By default, the emacs syntax is used. See Appendix B
- for a list of keystrokes, effects, and ways to select between the two
- command sets.
- </para>
-
- <para>
- You can also use the arrow keys to edit commands. The left and right arrow
- keys move the cursor in the current Command Line. Typing ENTER at any
- location on the Command Line executes the command. Note that both the
- BACKSPACE and DELETE keys will delete one character to the left of the
- cursor.
- </para>
-
- <para>
- MGED keeps a history of commands that have been entered. The up and down
- arrow keys allow you to select a previously executed command for editing
- and re-execution.
- </para>
- </sect1>
-
- <sect1>
- <title>Quitting MGED</title>
-
- <para>
- Remember, to leave the program at any time, type from the Command Line
- either the letter q or the word quit and then press the ENTER key. You may
- also quit the program by selecting Exit from the File menu.
- </para>
- </sect1>
-
- <sect1>
- <title>Review</title>
-
- <para>
- In this lesson, you:
-
- <itemizedlist mark='bullet'>
- <listitem>
- <para>Started the MGED program.</para>
- </listitem>
- <listitem>
- <para>Entered commands in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Used the MGED GUI.</para>
- </listitem>
- <listitem>
- <para>Created or opened a database using MGED naming conventions.</para>
- </listitem>
- <listitem>
- <para>Used the GUI to create or open a database.</para>
- </listitem>
- <listitem>
- <para>Titled a database.</para>
- </listitem>
- <listitem>
- <para>Selected a unit of measure for a design.</para>
- </listitem>
- <listitem>
- <para>Selected a primitive shape.</para>
- </listitem>
- <listitem>
- <para>Created a primitive shape using the make command in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Cleared the screen of a design using the Z command.</para>
- </listitem>
- <listitem>
- <para>Drew a previously created shape using the draw command.</para>
- </listitem>
- <listitem>
- <para>Used the erase command to delete a shape from the Graphics Window display.</para>
- </listitem>
- <listitem>
- <para>Used the GUI to create a primitive shape.</para>
- </listitem>
- <listitem>
- <para>Used the l command to view a shape's parameters.</para>
- </listitem>
- <listitem>
- <para>Used the ls command to list the contents of the database.</para>
- </listitem>
- <listitem>
- <para>Used the kill command to eliminate a shape from the database.</para>
- </listitem>
- <listitem>
- <para>Edited commands in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Used the q or Exit commands to quit the program.</para>
- </listitem>
- </itemizedlist>
- </para>
- </sect1>
- </chapter>
-
- <chapter id="Lesson-2">
- <title>Learning the Viewing Options</title>
-
- <para>
- In this lesson, you will:
-
- <itemizedlist mark='bullet'>
- <listitem>
- <para>Create a model radio.</para>
- </listitem>
- <listitem>
- <para>Locate viewing information in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Identify elements of the MGED viewing system.</para>
- </listitem>
- <listitem>
- <para>View your radio from different angles.</para>
- </listitem>
- <listitem>
- <para>Work with Shift Grips.</para>
- </listitem>
- </itemizedlist>
- </para>
-
- <para>
- Models in BRL-CAD are constructed in a single xyz coordinate system, which
- we sometimes refer to as model space. The Graphics Window of MGED displays
- a portion of this space. The xyz coordinate system is used for specifying
- both the geometry and the view of the geometry that is presented in the
- Graphics Window.
- </para>
-
- <para>
- MGED offers a default view and a variety of optional views. You can switch
- back and forth between these views during and after model creation. This
- lesson is designed to help you understand the viewing process and options.
- </para>
-
- <sect1>
- <title>Creating a Radio</title>
-
- <para>
- To gain practice viewing actual geometry, let's build a simple geometric
- object-a "walkie-talkie" radio. Note that the commands we use to do this
- are not discussed here because our current concern is on applying the
- principles of viewing. Later lessons on creating geometry address these
- commands in detail. Begin by launching MGED and creating a new database
- named radio.g. Remember that one way to do this is to type the following
- command in a Terminal Window:
-
- <command>$ mged radio.g</command>
- </para>
-
- <para>
- Type the following in the Command Window, carefully checking each line
- before pressing ENTER. If you make a mistake, use BACKSPACE or the left/
- right arrow keys to make corrections before pressing ENTER (see Appendix B
- for the editing command list).
- </para>
-
- <note>
- <para>
- Be especially careful to note the difference between the numeral one
- [1] and the letter l [l] in ell1 on the third line.
- </para>
- </note>
-
- <literallayout>
- in body.s rpp 0 16 0 32 0 48[ENTER]
-
- in btn.s rec 8 30 36 0 3 0 4 0 0 0 0 2[ENTER]
-
- in btn2.s ell1 8 33 36 4 0 0 2[ENTER]
-
- in spkr.s tor 16 16 16 1 0 0 12 1[ENTER]
-
- in ant.s rcc 2 2 46 0 0 48 1[ENTER]
-
- in knob.s rcc 4 4 40 8 0 0 5[ENTER]
- </literallayout>
-
-
- <note>
- <para>
- Note that in the preceding Command Line expressions, btn is an
- abbreviation for button, ant is an abbreviation for antenna, and spkr
- is an abbreviation for speaker. Also note that the numbers could have
- been separated by single spaces. The extra spaces were inserted
- simply to improve readability. For some usages (e.g., the r and comb
- commands, which are discussed later), the number of spaces has to be
- exact.
- </para>
- </note>
-
- <para>
- An image similar to the following should now appear in the Graphics
- Window.
-
- <figure>
- <title> Default View of a Radio</title>
- <screenshot>
- <graphic fileref="defaultradio.png"/>
- </screenshot>
- </figure>
- </para>
- </sect1>
-
- <sect1>
- <title>Locating Viewing Information in the Command Window</title>
- <para>
- Now take a minute to look at the Command Window. Even if nothing is in the
- window, enclosed in the bottom border is a string of information about the
- Graphics Window. An example string might read:
-
- <literal>cent=(8.000 16.000 24.000) sz=96.000 mm az=35.00 el=25.00 tw=-0.00
- ang=(0.00 0.00 0.00)</literal>
- </para>
- <para>
- As detailed in the following table, this information contains four groups
- of viewing data about the Graphics Window.
-
- <table frame='all'><title>Viewing Data at the Bottom of the Command Window</title>
- <tgroup cols='5' align='center' colsep='1' rowsep='1'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <colspec colname='c5'/>
- <thead>
- <row>
- <entry>Screen Designation</entry>
- <entry>Viewing Information</entry>
- <entry>Location of Variables</entry>
- <entry>Default Units</entry>
- <entry>Default Values</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>cent=</entry>
- <entry>Center of View</entry>
- <entry>First 3 numbers</entry>
- <entry>Millimeters</entry>
- <entry>0.000 0.000 0.000</entry>
- </row>
- <row>
- <entry>sz=</entry>
- <entry>Size of View</entry>
- <entry>4th number</entry>
- <entry>Millimeters</entry>
- <entry>Dependent upon size selected</entry>
- </row>
- <row>
- <entry>az=</entry>
- <entry morerows='1' valign='middle'>Viewing Angle</entry>
- <entry morerows='1' valign='middle'>5th and 6th numbers</entry>
- <entry morerows='1' valign='middle'>Degrees</entry>
- <entry>35.00</entry>
- </row>
- <row>
- <entry>el=</entry>
- <entry>25.00</entry>
- </row>
- <row>
- <entry>tw=</entry>
- <entry>Twist</entry>
- <entry morerows='1' valign='middle'>7th-10th numbers</entry>
- <entry morerows='1' valign='middle'>Degrees</entry>
- <entry>0.00</entry>
- </row>
- <row>
- <entry>ang=</entry>
- <entry>Angle of View</entry>
- <entry>0.00 0.00 0.00</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
- </para>
- </sect1>
-
- <sect1>
- <title>Identifying Elements of the MGED Viewing System</title>
-
- <sect2>
- <title>Center of View</title>
- <para>
- The first set of information tells you the center of what you are viewing.
- You can change the center of where you are looking through both the GUI
- and the Command Window.
- </para>
- <para>
- To change the center of your view of the radio using the GUI, press the
- SHIFT key and any mouse button while dragging the mouse. (This is an
- example of a Shift Grip, which is described later in this chapter.) You
- can also change the center of view by placing the mouse pointer where you
- want the center to be and clicking the middle mouse button.
- </para>
- <para>
- To change the center of view using the Command Window, simply type at the
- prompt the word center followed by three values for x, y, and z (which is
- the 3-D coordinate system mentioned previously). For example:
-
- <command>center 0 15 325.735[Enter]</command>
-
- As you change your view of the geometry, notice that the numbers in the
- brackets after the cent= title will change to reflect the new center of
- the view.
- </para>
- </sect2>
-
- <sect2>
- <title>Size of View</title>
-
- <para>
- The size of the view is the amount of model space that is shown in the
- Graphics Window. For example, consider using a camera with a zoom lens to
- photograph a rose. As shown in the following figures, if you zoom in on
- the rose, it will appear large in relation to your viewing field. If you
- zoom out, it will appear smaller. In actuality, the view size for the rose
- image on the left might represent only 15 mm across while the view size
- for the image on the right might represent 100 mm across. In both cases,
- however, the actual size of the rose is the same.
- </para>
-
- <informaltable>
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Zoom In to View Details (small size of view)</entry>
- <entry>Zoom Out to View Object
- in Relation to Environment (large size of view)</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- To change the view size of your radio through the GUI, click the right
- mouse button to zoom in and the left mouse button to zoom out. Each time
- you click the left or right mouse button, the view of the design will
- increase or decrease in size by a factor of 2 (i.e., two times larger or
- two times smaller than the previous size).
- </para>
- <para>
- You can also zoom in or out on your design by going to the View menu and
- selecting Zoom In or Zoom Out. A drawback to this method is that you can
- only zoom in or out one time because the drop-down menu closes once you
- make a selection.
- </para>
- <para>
- If you get lost at any point while creating a model, you can use the zap
- (Z) command to clear the geometry from the Graphics Window and then recall
- the shape with the draw command. When drawing in an empty Graphics Window,
- MGED automatically sizes the view to fit what you draw into the window.
- </para>
- <para>
- You can control the view size of your radio more accurately with the
- Command Window. To set the size to 100 (of whichever units you have
- selected), type at the prompt:
-
- <command>size 100[Enter]</command>
- </para>
- <para>
- You can also zoom in or out on a design by typing zoom on the Command
- Line. To make your radio appear 50% smaller, you would type:
-
- <command>zoom 0.5[Enter]</command>
- </para>
- <para>
- To make your radio appear twice as large, you would type:
-
- <command>zoom 2[Enter]</command>
- </para>
-
- <note>
- <para>
- Remember that changing the view size does NOT affect the size of the
- object. You will change the size of an object in Lesson 6.
- </para>
- </note>
- </sect2>
-
- <sect2>
- <title>Angle of View</title>
-
- <para>
- Azimuth, elevation, and twist (all measured in degrees) determine where
- you are in relation to the object you are viewing. Azimuth determines
- where you are around the sides of it (i.e., to the front, left, right,
- behind, or somewhere in between), elevation determines where you are above
- or below it, and twist determines the angle you are rotated about the
- viewing direction.
- </para>
- <para>
- To better understand azimuth, imagine walking around a truck with a camera
- to photograph it. As shown in the following illustrations, you would be at
- 0'0 azimuth if you stood directly in front of the truck to take its
- picture. If you circled around slightly to your right, you would be at
- 35'0 azimuth. If you moved further around until you were looking directly
- at the driver's side (in U.S. trucks), you would be at 90'0 azimuth.
- Standing behind it would put you at 180'0 azimuth. If you were facing the
- passenger's side, you would be at 270'0 azimuth.
- </para>
-
- <note>
- <para>
- The terms azimuth, elevation, and twist are similar to the terms yaw,
- pitch, and roll, respectively, which are common terms in the
- aerospace industry.
- </para>
- </note>
-
-
- <informaltable frame="none">
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Front (az=0, el=0)</entry>
- <entry>az=35, el=0</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <informaltable frame="none">
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Left (az=90, el=0)</entry>
- <entry>Rear (az=180, el=0)</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <informaltable frame="none">
- <tgroup cols='1'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Right (az=270, el=0)</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- Elevation, on the other hand, involves the viewer's position above or
- below an object. In the preceding example, you circled around a truck
- without changing your relative height. You had an elevation of 0'0, which
- means you were level with it. As the following figures illustrate,
- however, imagine stopping at the 35'0 azimuth position and then climbing a
- ladder to photograph the truck from 25'0 elevation. Climbing higher, you
- would be at 60'0 elevation. If you were directly above it with the camera
- facing down, you would be at 90'0 elevation. If you crawled under the
- truck and looked directly up at it, you would be at -90'0 elevation.
- </para>
-
- <informaltable frame="none">
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>az=35, el=0</entry>
- <entry>az=35, el=25</entry>
- </row>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>az=35, el=60</entry>
- <entry>az=35, el=90</entry>
- </row>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Top (az=270, el=90)</entry>
- <entry>Bottom (az=270, el=-90)</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- Finally, twist (which is an optional setting in MGED) specifies a rotation
- about the viewing direction. This rotation is applied to the view after
- azimuth and elevation have been designated. So, returning to our truck
- example, imagine standing in front of the vehicle (az=0, el=0) and then
- tilting your camera counterclockwise 14'0. This would give your view a
- 14'0 twist angle, as shown in the following figure (on the left). Note
- again that it is not the truck that is tipped up, but simply your view of
- it. For more information on specifying twist, see the <command>ae</command> command in
- Appendix A.
-
- <informaltable frame="none">
- <tgroup cols='1'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Front (az=0, el=0, tw=14)</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
- </para>
- </sect2>
- </sect1>
-
- <sect1>
- <title>Summing up on Azimuth and Elevation and the xyz Coordinate System</title>
-
- <para>
- As mentioned at the start of this lesson, MGED operates in a
- three-dimensional coordinate system (determined by the x, y, and z axes).
- Azimuth is measured in the xy plane with the positive x direction
- corresponding to an azimuth of 0'0. Positive azimuth angles are measured
- from the positive x axis toward and past the positive y axis. Negative
- azimuth angles are measured in the other direction.
- </para>
-
- <figure>
- <title>Azimuth, Elevation, and the xyz Coordinate System</title>
- <screenshot>
- <graphic fileref="coordsystem.png"/>
- </screenshot>
- </figure>
-
- <para>
- If the azimuth angle is 0, then elevation is measured in the xz plane with
- +90'0 corresponding to the positive z direction and -90'0 corresponding to
- the negative z direction. However, if azimuth is not 0, these angles are
- in a plane aligned with the azimuth direction.
- </para>
- </sect1>
-
- <sect1>
- <title>Viewing Your Radio from Different Angles</title>
-
- <para>
- Let's now experiment with different views of your radio. MGED has several
- standard default views, which you've already seen in the preceding truck
- example. They include Top (az270, el90); Bottom (az270, el-90); Right
- (az270, el0); Left (az90, el0); Front (az0, el0); Rear (az180, el0); az35,
- el25; and az45, el45.
- </para>
-
- <para>
- Go to the View menu and try viewing your radio from different angles.
- </para>
-
- <informaltable frame="none">
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Top</entry>
- <entry>az35,el25</entry>
- </row>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Right</entry>
- <entry>Front</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- You can also select any azimuth-elevation combination from the Command
- Line. For example, at the prompt type
-
- <command>ae 128 17[Enter]</command>
-
- As with many of the Command Line options, this method of selecting views
- provides a finer degree of control/precision when you need it.
- </para>
-
- <para>
- MGED can also display multiple views simultaneously. Go to the Modes menu
- and click on Multipane. Four small panes with different views should
- appear in your Graphics Window, as shown in the following illustration.
- </para>
-
-
- <figure>
- <title>Multipane View of the Radio</title>
- <screenshot>
- <graphic fileref="multradioviews.png"/>
- </screenshot>
- </figure>
- </sect1>
-
- <sect1>
- <title>Working with Shift Grips</title>
-
- <para>
- The Shift Grip options of MGED are handy hot-key and mouse button
- combinations that can be used in two different ways. With regard to our
- present discussion on viewing, the Shift Grips can, in effect, "drag" the
- world around in front of the viewer (but without actually changing the
- coordinates of the viewed objects). The same Shift Grips can also be used
- in Edit mode to actually move or alter the geometry of your objects. In
- both cases, the Shift Grips appear to do the same thing, so it is
- important always to know the mode in which you are operating.
- </para>
-
- <para>
- In general, the SHIFT key translates (moves), the CTRL key rotates, and
- the ALT key constrains (or limits) translation or rotation to a particular
- axis (x, y, or z). These axes correspond to the three mouse buttons as
- follows: the left button represents the x axis, the middle button
- represents the y axis, and the right button represents the z axis. In
- addition, the SHIFT and CTRL keys can be used in conjunction with any
- mouse button to scale an object (although the ALT key will not constrain
- this action). The following table lists all of the key bindings and their
- functions.
- </para>
-
- <table frame='all'>
- <title>Shift Grip Keys and Effects</title>
- <tgroup cols='5' align='center' colsep='1' rowsep='1'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <thead>
- <row>
- <entry>Function</entry>
- <entry>Key Combination</entry>
- <entry>Effect in Normal Viewing</entry>
- <entry>Effect in Edit Mode</entry>
- </row>
- </thead>
- <tbody>
- <row>
- <entry>Translate (Move)</entry>
- <entry>SHIFT + any mouse button + mouse drag</entry>
- <entry>Moves view in any direction</entry>
- <entry>Translates object in any direction</entry>
- </row>
- <row>
- <entry>Rotate</entry>
- <entry>CTRL + any mouse button + mouse drag</entry>
- <entry>Rotates view in any direction</entry>
- <entry>Rotates object in any direction</entry>
- </row>
- <row>
- <entry morerows='2' valign='middle'>Constrain Translation</entry>
- <entry>SHIFT + ALT + left mouse button + mouse drag</entry>
- <entry>Moves view in the x direction</entry>
- <entry>Translates object in the x direction</entry>
- </row>
- <row>
- <entry>SHIFT + ALT + middle mouse button + mouse drag</entry>
- <entry>Moves view in the y direction</entry>
- <entry>Translates object in the y direction</entry>
- </row>
- <row>
- <entry>SHIFT + ALT + right mouse button + mouse drag</entry>
- <entry>Moves view in the z direction</entry>
- <entry>Translates object in the z direction</entry>
- </row>
- <row>
- <entry morerows='2' valign='middle'>Constrain Rotation</entry>
- <entry>CTRL + ALT + left mouse button + mouse drag</entry>
- <entry>Rotates view about the x axis</entry>
- <entry>Rotates object about the x axis</entry>
- </row>
- <row>
- <entry>CTRL + ALT + middle mouse button + mouse drag</entry>
- <entry>Rotates view about the y axis</entry>
- <entry>Rotates object only about the y axis</entry>
- </row>
- <row>
- <entry>CTRL + ALT + right mouse button + mouse drag</entry>
- <entry>Rotates view about the z axis</entry>
- <entry>Rotates object aboutthe z axis</entry>
- </row>
- <row>
- <entry>Scale</entry>
- <entry>SHIFT + CTRL + any mouse button + mouse drag</entry>
- <entry>Scales view larger or smaller</entry>
- <entry>Scales object larger or smaller</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
-
- <caution>
- <para>
- Depending on your window manager or desktop environment settings,
- some key combinations may already be designated to perform other
- tasks (e.g., resizing or moving a window). If so, you may need to
- adjust settings to allow the Shift Grip options to function.
- Furthermore, left-handed users may have switched the behavior of the
- left and right mouse buttons in their system configurations. In such
- instances, the terms left mouse button and right mouse button should
- be switched throughout this document.
- </para>
- </caution>
-
- <para>
- Probably the easiest way to familiarize yourself with the Shift Grip
- options is to try them out on your radio. Using the preceding table as a
- guide, experiment with translating, rotating, constraining translation and
- rotation to particular axes, and sizing your radio view.
- </para>
-
- <note>
- <para>
- Remember, although the Shift Grip options may appear to be
- manipulating objects, unless you are in Edit mode they are only
- manipulating your view of the objects.
- </para>
- </note>
- </sect1>
-
- <sect1>
- <title>Review</title>
-
- <para>
- In this lesson, you:
-
- <itemizedlist mark='bullet'>
- <listitem>
- <para>Created a model radio.</para>
- </listitem>
- <listitem>
- <para>Located viewing information in the Command Window.</para>
- </listitem>
- <listitem>
- <para>Identified elements of the MGED viewing system.</para>
- </listitem>
- <listitem>
- <para>Viewed your radio from different angles.</para>
- </listitem>
- <listitem>
- <para>Worked with Shift Grips.</para>
- </listitem>
- </itemizedlist>
- </para>
- </sect1>
- </chapter>
-
- <chapter id="Lesson-3">
- <title>Using the Insert Command to Size and Place Shapes</title>
-
- <para>
- In this lesson, you will:
-
- <itemizedlist mark='bullet'>
- <listitem>
- <para>Create a sphere and a right circular cylinder using the make command.</para>
- </listitem>
- <listitem>
- <para>Create the same two shapes using the in (insert) command.</para>
- </listitem>
- <listitem>
- <para>Combine arguments on the Command Line to streamline the entry of variables.</para>
- </listitem>
- <listitem>
- <para>Develop a combined-command form to help manage Command Line variables.</para>
- </listitem>
- <listitem>
- <para>Consider conventions for choosing names for your objects.</para>
- </listitem>
- <listitem>
- <para>View your shapes from different perspectives using options of the View menu.</para>
- </listitem>
- <listitem>
- <para>Quit the MGED program.</para>
- </listitem>
- </itemizedlist>
- </para>
-
- <para>
- This lesson focuses on creating shapes from the Command Window using the
- make and in commands. You will create a sphere (sph) and a right circular
- cylinder (rcc) using both commands so that you can see how each command
- works. Later in the lesson, you will practice viewing your model from
- different angles.
- </para>
-
- <sect1>
- <title>Creating a New Database from the Command Window</title>
-
- <para>
- Create a new database and name it shapes.g. Title your database myShapes.
- </para>
- </sect1>
-
- <sect1>
- <title>Creating a Sphere Using the Make Command</title>
-
- <para>
- Begin by making the Command Window active (usually by clicking anywhere in
- the window). Then, at the MGED prompt, type in the command:
-
- <command>make sph1.s sph [Enter]</command>
- </para>
-
- <para>
- As noted in Lesson 1, this command tells MGED to:
-
- <informaltable frame="all">
- <tgroup cols='3'>
- <tbody>
- <row><entry>make</entry><entry>sph1.s</entry><entry>sph</entry></row>
- <row><entry>Create a shape</entry><entry>Name it sph1.s</entry>
- <entry>Make it a sphere</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <figure>
- <title>Wireframe Sphere</title>
- <screenshot>
- <graphic fileref="wireframesphere.png"/>
- </screenshot>
- </figure>
- </para>
-
- <para>
- A sphere shape has now been created, and a wireframe drawing should appear
- in your Graphics Window.
- </para>
- <para>
- To make the rcc from the Command Window prompt, type:
-
- <command>make rcc1.s rcc[Enter]</command>
- </para>
-
- <para>
- Your Graphics Window should now display a large rcc that, from the default
- view of az35, el25, looks as if it intersects the sphere you previously
- created.
-
- <figure>
- <title>Wireframe Sphere and Right Circular Cylinder</title>
- <screenshot>
- <graphic fileref="wireframespherecylinder.png"/>
- </screenshot>
- </figure>
- </para>
-
- <para>
- Using the make command is a fast and easy way to create a shape; however,
- most models are going to require shapes that have specific parameters,
- such as height and radius. So, a more precise way to create these shapes
- is to use the in (insert) command.
- </para>
- </sect1>
-
- <sect1>
- <title>Using the In Command to Create Shapes</title>
-
- <para>
- Begin by making the Command Window active (usually done by clicking
- anywhere in the window). Then, use the Z (zap) command to clear the
- Graphics Window. You are now ready to create a sphere using the in
- command. At the MGED prompt type:
-
- <command>in sph2.s sph[Enter]</command>
- </para>
-
- <para>
- MGED will respond with:
-
- <literal>Enter X, Y, Z of vertex:</literal>
- </para>
-
- <para>
- You must tell MGED where to position the vertex (center) of your sphere in
- space. Type at the MGED prompt:
-
- <command>4 4 4[Enter]</command>
- </para>
-
- <note>
- <para>
- As you work in MGED, you will often be asked to enter a value for a
- vector or a vertex. In MGED, a vector represents the distance and
- direction from one point in space to another, and a vertex is one
- single point in space. The values entered for a vector are typically
- used to create an object with specific dimensions. The values entered
- for a vertex place the object in space.
- </para>
- </note>
-
- <para>
- Your sphere will now be placed at (x,y,z)=(4,4,4), as measured in
- millimeters. Notice that the numbers are separated by spaces followed by
- the ENTER key. MGED will now ask you to:
- </para>
- <literallayout>
- Enter radius:
-
- Type in:
-
- 3[Enter]
- </literallayout>
-
- <para>
- The radius of your sphere will be 3 mm. The following is the dialog that
- should appear in your Command Window (including the appropriate
- responses).
-
- <command>mged> in sph2.s sph</command>
-
- <literal>Enter X, Y, Z of vertex: 4 4 4</literal>
-
- <literal>Enter radius: 3</literal>
-
- <literal>51 vectors in 0.000543 sec</literal>
-
- The last line of this dialog is simply a record of the computer's speed in
- drawing the shape. It has no real usefulness to the user at this point.
- </para>
-
- <para>
- A sphere has now been created, and a wireframe drawing similar to the one
- created using the make command should appear in your Graphics Window.
- </para>
-
- <para>
- To make the right circular cylinder, type at the Command Window prompt:
-
- <command>in rcc2.s rcc[Enter]</command>
-
- MGED will ask you to enter values for x, y, and z of the vertex (where you
- want the center of one end of the rcc placed in space). Type:
-
- <command>4 4 0[Enter]</command>
-
- Be sure to leave spaces between each of these numbers.
- </para>
-
- <para>
- MGED will now ask you to enter the x, y, and z values of the height (H)
- vector (i.e., how long you want the rcc to be). Type:
-
- <command>0 0 4[Enter]</command>
-
- The last value you will need to enter is the radius of the rcc. Type:
-
- <command>3[Enter]</command>
-
- The dialog in the Command Window for the creation of the rcc should look
- like this:
- </para>
-
- <literallayout>
- mged> in rcc2.s rcc
-
- Enter X, Y, Z of vertex: 4 4 0
-
- Enter X, Y, Z of height (H) vector: 0 0 4
-
- Enter radius: 3
-
- 42 vectors in 0.000214 sec
- </literallayout>
-
- <para>
- You should now have new versions of the sphere and rcc shapes. Notice how
- these two shapes compare in size to the first two you created. The rcc is
- now in proportion to the sphere and is placed in space off to the left in
- your Graphics Window. By specifying the dimensions of the shapes and their
- locations in space, you were able to create the model more precisely.
- </para>
-
- <informaltable>
- <tgroup cols='2'>
- <tbody>
- <row>
- <entry><graphic/></entry>
- <entry><graphic/></entry>
- </row>
- <row>
- <entry>Shapes Created with Make Command</entry>
- <entry>Shapes Created with In Command</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- </sect1>
-
- <sect1>
- <title>Combining Arguments on One Line</title>
-
- <para>
- Another way to use the in command is to combine all of the required
- information on one line. Once you become familiar with using the in
- command, you will probably prefer to use this method as it allows you to
- input all the parameter values more quickly.
- </para>
-
- <para>
- Clear the Graphics Window by using the Z command. Now make another sphere
- by typing after the MGED prompt:
-
- <command>in sph3.s sph 4 4 4 3[Enter]</command>
- </para>
-
- <para>
- The meaning of this longer form of the command is:
- </para>
-
-
- <informaltable>
- <tgroup cols='7'>
- <tbody>
- <row>
- <entry>in</entry>
- <entry>sph3.s</entry>
- <entry>sph</entry>
- <entry>4</entry>
- <entry>4</entry>
- <entry>4</entry>
- <entry>3</entry>
- </row>
- <row>
- <entry>Insert a primitive shape</entry>
- <entry>Name it sph3.s</entry>
- <entry>Make the primitive shape a sphere</entry>
- <entry>Make the x of the vertex a value of 4</entry>
- <entry>Make the y of the vertex a value of 4</entry>
- <entry>Make the z of the vertex a value of 4</entry>
- <entry>Make the radius a value of 3</entry>
- </row>
- </tbody>
- </tgroup>
- </informaltable>
-
- <para>
- To make the right circular cylinder using this method, type after the MGED
- prompt:
-
- <command>in rcc3.s rcc 4 4 0 0 0 4 3[Enter]</command>
- </para>
-
- <para>
- The meaning of this command is:
- </para>
-
- <informaltable>
- <tgroup cols='10' align='center' colsep='1' rowsep='1'>
- <colspec colname='c1'/>
- <colspec colname='c2'/>
- <colspec colname='c3'/>
- <colspec colname='c4'/>
- <colspec colname='c5'/>
- <colspec colname='c6'/>
- <colspec colname='c7'/>
- <colspec colname='c8'/>
- <colspec colname='c9'/>
- <colspec colname='c10'/>
- <tbody>
- <row>
- <entry>in</entry>
- <entry>rcc3.s</entry>
- <entry>rcc</entry>
- <entry>4</entry>
- <entry>4</entry>
- <entry>0</entry>
- <entry>0</entry>
- <entry>0</entry>
- <entry>4</entry>
- <entry>3</entry>
- </row>
- <row>
- <entry morerows='1' valign='top'>Insert a primitive shape</entry>
- <entry morerows='1' valign='top'>Name it rcc3.s</entry>
- <entry morerows='1' valign='top'>Make the primitive shape a right circular cylinder</entry>
- <entry morerow...
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