Light ROM 4/Light ROM 4 - Disc 1.iso/text/lwfaq.doc

Text File | 1996-01-01 | 40KB | 950 lines

From:     [1]Michael B. Comet
Subject:  Lightwave 3D FAQ - Frequently Asked Questions 9/3/1996
Date:     3 Sep 1996 14:50:40 GMT
Group(s):
          [2]comp.graphics.apps.lightwave


+======================================================================+
|                             Lightwave 3D                             |
|                      FREQUENTLY ASKED QUESTIONS                      |
|----------------------------------------------------------------------|
|                              Written By                              |
|                           Michael B. Comet                           |
+======================================================================+

        This is the Frequently Asked Questions posting for the Lightwave
3D Mailing list and Newsgroup.  This posting is sent every so often to
answer general questions that users of the 3D rendering software,
Lightwave 3D by NewTek may have.  It is aimed toward all users,
especially newcomers to the program.

        Please note that this FAQ is also available on the World Wide
Web at: http://cnswww.cns.cwru.edu/php/comet/LW/

        If you find any errors or have answers to other frequently asked
questions that you would like to have included in this posting, please
send e-mail to: [e-mail]

        - Mike C.

========================================================================

                       COPYRIGHT & DISCLAIMER

The Lightwave 3D FAQ is Copyright 1995,1996 Michael B. Comet.
  All Rights Reserved.

No portion of the Lightwave 3D FAQ my be duplicated in part or in whole,
by any means electronic or otherwise without prior written consent of
the author.  The Lightwave 3D FAQ may not be sold either individually
or as part of other material.  The Lightwave 3D FAQ may be distributed
via electronic mail, Usenet news and other internet resources so long
as no charge is incurred for the actual document itself.

There is no guarantee regarding any information presented in this
document either implicit or implied.  The information may not be
correct, useful or helpful.  The reader accepts ALL responsibility for
actions pertaining to reading this document regardless of consequence.

========================================================================

Date          : August 27, 1996 Thu.
Issue Number  : 6
What's New    : Section 1, #1 New email address for NewTek Bug reports
                Section 2, #5 Added note about Reduce Polygon Plug-In
                Section 2, #6 How to create particles
                Section 2, #7 Modeling with Metanurbs - Tips and tricks
                Section 3, #4 Updated surface pasting from test render
                Section 4, #5 Added info about spline settings
                Section 4, #7 Added info about Tablet button in Layout
                Section 4, #8 Moving and Rotating objects in a hierarchy
                Section 4, #9 Complex object deformation through paths
               *Section 4, #10 AVI Saving Problems with Windows 95
               *Section 4, #11 Lightwave crashing with animation savers
                Section 4, #12 Grid Size and precision in moving objects
                Section 4, #13 Help with Inverse Kinematics (IK)
                Section 4, #14 Joint Compensation and Muscle Flexing

(* indicates not available due to waiting for authorization)

Current Version of LW as of this FAQ:  LW 5.0 rev C

------------------------------------------------------------------------

CONTENTS:
=========

    SECTION 1 - Support/Products/Sites
         1] How do I reach NewTek?
         2] Lightwave related: References/Help Books/Magzines/FTP sites.
         3] What is the Lightwave Newsgroup and Mailing List and how
            can I obtain it?
         4] Is there any documentation regarding the 3D Object File
            format for Lightwave Objects?
         5] How can I write my own Plug-Ins for Lightwave?
         6] I am having problems installing LW from the CD-ROM!
         7] I am having problems transfering scene files from the PC to
            the Amiga

    SECTION 2 - Lightwave Modeler
         1] How do I merge multiple layers into one layer?
         2] How can I save an object so that data gets loaded back into
            its original layer?
         3] My object has duplicate polygons, how do I remove them?
         4] Why on the Amiga version of Modeler am I getting the error
            message "Internal buffer too small"
         5] Is there a way to "Un-metaform"?
         6] How do I create particles?
         7] Modeling with Metanurbs - Tips and tricks

    SECTION 3 - Lightwave Layout - Surfaces and Textures
         1] List of common Index of Refractions (and not so common too!)
         2] I texture my object and save my scene, but next time I
            load the scene the settings are gone!
         3] My Lens Flares fade behind objects I don't want them too!
         4] How can I copy a surface and paste it onto another?
         5] How can I measure the size of my object to figure out
            texture sizes?
         6] I am having problems getting LW to load 256 color images
            without expanding them to truecolor (24 bit)
         7] I am rendering an object with bones but my polygons seem to
            keep getting errors or are not smooth!
         8] Why are my smaller objects with the glow effect not really
            showing a glow?
         9] How come edge transparency doesn't seem to function for
            flat polygons?
        10] How do I use Image Sequences?

    SECTION 4 - Lightwave Layout - Animation
         1] I move my objects into position, but they keep "forgetting"
            where they were.
         2] I have problems setting bones for my object.  My object
            keeps resizing or changing.
         3] Can I click on an item to select it in Layout?
         4] Whenever I create a preview wireframe animation, my objects
            don't show up, but I can see Lightsources and paths.
         5] How can I copy a keyframe for an item?
         6] Quick Spline Control Tips
         7] I have problems trying to position objects with my WACOM
            tablet!
         8] How come when I rotate objects or bones in a hierarchy they
            don't rotate or move the way I expect?
         9] How can I make objects that flow around and through complex
            turns?
       *10] I am having problem with the AVI saver and Windows 95!
       *11] Lightwave crashes when trying to render animation files out!
        12] When I load a large object, I find I can't position the
            camera or other objects with enough precision.
        13] I am trying to use Inverse Kinematics (IK) but it doesn't
            seem to work correctly.
        14] I have turned on joint compensation and muscle flexing for
            some bones but nothing seems to happen.

========================================================================
                   SECTION 1 - Support Products/Sites
========================================================================

1] How do I reach NewTek?

    NewTek, Inc.
    Executive Offices
    1200 SW Executive Drive
    Topeka, KS 66615

    Voice:            913-228-8000
    FAX:              913-228-8001
    Customer Service: 800-847-6111
    Dealer Sales:     800-368-5441
    Dealer FAX:       [phone]

    TECHNICAL SUPPORT

    Voice:            913-228-8282
    FAX:              913-228-8222
    BBS:              913-271-9299


    E-Mail

    [e-mail]  - Feature Ideas and Requests
    [e-mail]        - Bug reports and Technical Questions

    Each of these addresses are monitored and read by people in the
    LightWave Group.


    Those with World Wide Web access might also wish to look at
    http://www.newtek.com/
    which has product information and pricing, tutorials, and more.

    In addition there is a NewTek FTP site at: ftp.newtek.com

------------------------------------------------------------------------

2] Lightwave related: References/Help Books/Magzines/FTP sites.

  REFERENCES AND HELP BOOKS:

    "Lightwave 3D Layout Reference and Modeler Reference", NewTek Inc., 1995
                   (Yes....read the manual!)

  MAGAZINES:

    These are some good graphics magazines, some focus on Lightwave, the
Video Toaster or general graphics.  If anyone has some other suggestions
please mail me the pertintent information.

    "LightWavePRO"
    Avid Media Group
    273 N. Mathilda Ave.
    Sunnyvale, CA 94086
    800-322-2843
    408-774-6770
            (LightWavePRO is the definitive LightWave Newsletter/journal
    for the LightWave user.)

    "LIGHTSPEED: The video Magazine for the Lightwave enthusiast"
    2763 West Ave L Suite 172
    Lancaster  CA 93636
    Voice: (800) 764 - 8696
       or  (805) 726 - 3545
            (Lightspeed is a new video magazine series released
    monthly that users can subscribe to.  Each issue contains many
    tutorials, product reviews, and animations.  Run Time per video is
    approx. 90-120 mins in length.  Each issue also contains tutorials
    and reviews by different people so you get a variety of styles and
    techniques.)

    "Video Toaster User"
    Avid Media Group
    273 N. Mathilda Ave.
    Sunnyvale, CA 94086
    800-322-2843 USA
    408-774-6770
            (A magazine focusing specifically on NewTeks Video
    Toaster device.  Also has a Lightwave column.)

    "Computer Artist"
    P.O. Box 3188
    Tulsa, OK 74101
    Voice: (918) 831 - 9405
    FAX:   (918) 831 - 9555
        (A magazine specifically for computer artists.  Articles on
    software and methods from Amigas, PC's and MAC's)

    "Computer Graphics World"
    P.O Box 122
    Tulsa, OK 74101-9845
    (800) 443 - 6632
    (918) 835 - 3161 ext. 400
    (918) 831 - 9497 (FAX)
            (A general computer graphics magazine focusing on the
    latest technology from PC's to SGI's)

    "AV Video"
    Montage Publishing Inc.
    P.O Box 16925
    North Hollywood, CA 91615
         or
    701 Wetchester Ave.
    White Plains, NY 10604
    Voice: (914) 328 - 9157
           (800) 800 - 5474
    FAX:   (914) 328 - 9093
        (An audio/video and computer magazine.  Has articles about all
    types of video and graphics applications including the Amiga and
    Video Toaster)

  FTP SITES:

    Those with internet access can use FTP to retrieve and send
Lightwave Objects, Scenes, Surfaces and more.

    FTP Site:  ftp.newtek.com
    Info:      NewTek's FTP server

    FTP Site:  tomahawk.welch.jhu.edu
    Path:      /pub/LW

    New items should be placed in the appropriate directory under
/pub/lw/incoming

------------------------------------------------------------------------

3] What is the LW Mailing List/Newsgroup and how can I obtain it?

Obtain access to Usenet news on the internet.  Then run your
newsreader software and use the USENET newsgroup for Lightwave:

        comp.graphics.apps.lightwave

    Once again this group is setup so that people may post questions,
answers and related discussions about Lightwave 3D.

        In addition there is a mailing list for Lightwave Users.
For information on this list send mail to:  [e-mail]
Place the text: INFO LIGHTWAVE
in the body of the message.  This will send back an automated set of
instructions.

------------------------------------------------------------------------

4] Is there any documentation regarding the 3D Object File format for
   Lightwave Objects?

    For documentaion on the 3D Object file format FTP to:

    FTP Site:   ftp.netcom.com
    Path:       pub/lw/lwsdk
    Filename:   fmtLWOB

------------------------------------------------------------------------

5] How can I write my own Plug-Ins for Lightwave?

You need to get the LightWave Server Developer Kit (LWSDK) which
contains headers, libraries, samples and documentation for plug-in
development.  The LWSDK is available for the Amiga OS, SGI IRIX, and
Win32 on Intel, MIPS and Alpha platforms.

The LWSDK is supported on the "lwplugin-l" mailing list.  To subscribe
to the list, send a message to "[e-mail]" with the message
body (subject is ignored):

        subscribe lwplugin-l <optional-email-address>

You will receive a informational message when you subscribe explaining
the list and how to get the LWSDK by FTP.  To get the informational
message without subscribing, send a message to the same address above
with the message body:

        info lwplugin-l

------------------------------------------------------------------------

6] I am having problems installing LW from the CD-ROM!

    Some CD-ROM drives have a problem reading certain files off of the
LW 4.0 Pre-release CD-ROM.  To do a complete install, run the LW install
again, but do not select PostScript Fonts.  Then manually copy the
fonts over from the CD-ROM when the installation completes.  Some
PostScripts fonts such as "Unitus" may not copy over.

------------------------------------------------------------------------

7] I am having problems transfering scene files from the PC to the Amiga

   The PC and Amiga handle Carrige Return and Line Feed characters
slightly differently.  You need to convert CR/LF <-> LF.  If you are
using CrossDOS turn on the file filter to do this.  CrossDOS will also
handle Control-Z EOF markers that DOS uses.  You can also strip out
the CTRL-M's on the Amiga side.

========================================================================
                  SECTION 2 - Lightwave Modeler
========================================================================

1] How do I merge multiple layers into one layer?

    Bring each layer you want to merge into the foreground.  (ie: Shift
click the foreground layer button for each layer).  Then select "Cut"
to remove all data and keep it in memory.  Then select "Paste" to
place all the data into the first selected foreground layer.

------------------------------------------------------------------------

2] How can I save an object so that data gets loaded back into its
   original layer?

    Normally when you save an object all foreground layers are simply
saved into the file and when reloaded placed into the first foreground
layer.  However, you can tell modeler to store information about what
was in each layer so when the object is reloaded, the data is placed
back into each original layer.

    Select the layers to save as foreground layers (like normal).  Then
press and hold the 'Alt' or 'Amiga' key while selecting "Save As".
Enter the filename to save the file as, you may still need to hold down
the 'Alt' key.  Now click the "Save As" button in the dialog while
holding down the 'Alt' key.  The object is saved with layer information.

------------------------------------------------------------------------

3] My object has duplicate polygons, how do I remove them?

    Sometimes you may have duplicate polygons on an object,  To remove
them choose 'Unify' from the 'Polygon' menu.

------------------------------------------------------------------------

4] Why on the Amiga version of Modeler am I getting the error message
   "Internal buffer too small"

    This is a known problem with 3.5a on the Amiga.  Obtain 3.5b.  A
patch is available on the ftp site: tomahawk.welch.jhu.edu or at the
NewTek site.

------------------------------------------------------------------------

5] Is there a way to "Un-metaform"?

    With Lightwave 5.0 there is a "Reduce_Polygons" plug in for modeler.
In modeler, select the tools menu, then custom and then Reduce_Polygons.

    Note that this plug in tends to create non-planar polygons.  So it
might not be useful for truly trying to un-metaform.

------------------------------------------------------------------------

6] How do I create particles?

    There are two types of particles.  Single point (your basic point
particle) and double point (a line).  You create them the same as any
other polygon.

    Select the point (or points) and choose "Make" from the polyon menu.
You will then have a one point or two point polygon.

------------------------------------------------------------------------

7] Modeling with Metanurbs - Tips and tricks

    Metanurbs provides an easy way to create complex organic shapes.
However there can be problems with getting 4 sides polygon objects,
and adding detail to metanurb objects.  Here are some tips.

    - Start with a cube, metaform it a few times to give enough
      starting polygons.  The resulting object will have 4 sided
      polygons.

    - You can extend polygons or add flanges to objects by using a
      bevel command.  If you continue to bevel you will get more
      segments.  When you bevel use a 0 value for the inset and
      some small amount for the shift.

    - You can merge polygons into 1 large 4 sided polygon.
      Then you can bevel that to make larger appendages.  Simply
      select adjacent polygons and choose Merge from the Polygon
      menu.  Note: in order to get a new 4 sided polygon you will
      have to merge specific polygons in your model.

    - You can individually select 4 sided polygons and do a smooth
      metaform to break it into 4 smaller 4 sided polygons.

========================================================================
           SECTION 3 - Lightwave Layout - Surfaces and Textures
========================================================================

1] List of common Index of Refractions (and not so common too!)

         (All items except Vacuum are in alphabetical order)
         (STP = Standard Temperature and Pressure)

         MATERIAL                      Index
         -------------------------------------
         Vacuum ...................... 1.00000 (exactly)

         Air (STP).................... 1.00029
         Acetone ..................... 1.36
         Alcohol ..................... 1.329
         Amorphous Selenium .......... 2.92
         Calspar1 .................... 1.66
         Calspar2 .................... 1.486
         Carbon Disulfide ............ 1.63
         Chromium Oxide .............. 2.705
         Copper Oxide ................ 2.705
         Crown Glass ................. 1.52
         Crystal ..................... 2.00
         Diamond ..................... 2.417
         Emerald ..................... 1.57
         Ethyl Alcohol ............... 1.36
         Flourite .................... 1.434
         Fused Quartz ................ 1.46
         Heaviest Flint Glass ........ 1.89
         Heavy Flint Glass ........... 1.65
         Glass ....................... 1.5
         Ice ......................... 1.309
         Iodine Crystal .............. 3.34
         Lapis Lazuli ................ 1.61
         Light Flint Glass ........... 1.575
         Liquid Carbon Dioxide ....... 1.20
         Polystyrene ................. 1.55
         Quartz 1 .................... 1.644
         Quartz 2 .................... 1.553
         Ruby ........................ 1.77
         Sapphire .................... 1.77
         Sodium Chloride (Salt) 1 .... 1.544
         Sodium Chloride (Salt) 2 .... 1.644
         Sugar Solution (30%) ........ 1.38
         Sugar Solution (80%) ........ 1.49
         Topaz ....................... 1.61
         Water (20 C) ................ 1.333
         Zinc Crown Glass ............ 1.517

------------------------------------------------------------------------

2] I texture my object and save my scene, but next time I load the
   scene the settings are gone!

    Surface settings are saved with the object file not the scene file.
After surfacing your object in layout, choose the "Object Panel" and
then "Save Object" (or save all objects).  Choose Yes to overwrite the
objects with the new coloring.  Next time you load the scene or load
the object into another scene the surfaces will be correct.

------------------------------------------------------------------------

3] My Lens Flares fade behind objects I don't want them too!

        Lens flares can fade out behind objects.  To do this simply
set "Fade Behind Objects" button in the Lens Flare panel.  However any
object with 'Cast Shadows' turned OFF will allow the flare to show
through (ie: it won't fade).  Thus by making say the glass in a bulb
not cast shadows, a flare inside will still show.  However if you move
the bulb behind an object that casts shadows the flare will fade behind.

------------------------------------------------------------------------

4] How can I copy a surface and paste it onto another?

    In Lightwave versions prior to 5.0 there was no actual cut and
paste operation.  However you can save the surface you want, select
the new surface and then load the previous settings into place.  The
usual way to do this is to select the source surface and then to save
the surface to a name such as 'temp.srf'.  Then select the target
surface and load temp.srf.

    With Lightwave 5.0 you can do a test render of the original surface.
Then select the new surface you want to paste to.  Click on the little
test rendering and a requester will appear asking if you wish to
overwrite the current surface settings with those that were used in the
test render.  Choose Yes and those settings are now assigned to the
current surface.

------------------------------------------------------------------------

5] How can I measure the size of my object to figure out texture sizes?

    There are two ways.  Once is to manually build several grid objects.
Basically create a flat cube in modeler with a set size and set number
of sections.  When you load it into layout you can use this as a
reference.  Under the 'Object' panel you can turn on "Polygon Edges" so
that the grid even shows during rendering.

    Another easy way is when starting to set your texture or imagemap,
select the default "Planar Texture" and then choose "Automatic Size".
Lightwave will then set the center information to the center of the
surface and the size to the size in meters of the surface.  Note this
works on a per surface not a per object basis.

------------------------------------------------------------------------

6] I am having problems getting LW to load 256 color images without
   expanding them to truecolor (24 bit)

     LW will load images from 2 bit to 24 bit.  If you are having
problems getting 8 bit (256 color) color images to stay at 8 bit to save
memory try renaming the file 'IFF' in the directory NEWTEK\HIIP\LOADERS\
2,4,8 bit and other IFF images should load properly after that.

------------------------------------------------------------------------

7] I am rendering an object with bones but my polygons seem to keep
   getting errors or are not smooth!

    Even if you create many polygons for your object you may need to
go into Modeler and 'Triple' your polygons.  What happens is as your
object bends, the 4 or more points that make up your polygons will
move and become non-planar.  This will cause Lightwave to become
confused when rendering the object.  To solve this, start Modeler,
load your object and choose 'Triple' from the 'Polygon' menu.  This is
a good idea for object animated with bones or displacement maps.

    In addition it is possible that the angle of the polygons is greater
than the allowed smoothing angle set in the surfaces menu.  Make sure
smoothing is selected for the surface and try raising the smoothing
angle if needed.

------------------------------------------------------------------------

8] Why are my smaller objects with the glow effect not really showing
   a glow?

    Small polygons, particles (single point polygons) and other objects
will glow with the glow effect.  However as the intensity of the glow
is relational to the surface area of the polygons.  More of a glow will
be created by numerous particles or polygons.

    In addition besides setting the surface to glow in the surface panel
you should check to make sure it is enabled globally in the 'Effects'
panel.

------------------------------------------------------------------------

9] How come edge transparency doesn't seem to function for flat
   polygons?

    The 'Edge Transparency' setting in the Surfaces panel is used to
create transparent edges on objects that are seen from a side and are
rounded, such as a sphere.  Flat polygons will not show any edge
transparency.  You may round them off and back to obtain the effect
but it may not look the way you want.

------------------------------------------------------------------------

10] How do I use Image Sequences?

    Lightwave has the ability to map a different image onto a surface
for each frame.  This feature known as Image Sequences can let you
place an "animation in an animation" such as a video inside of a 3D
television set.

    From the 'Images Panel' in Layout choose the 'Load Sequence' button.
Now simply choose the first image in the sequence.  The file extension,
sequence digits and offset are all set for you.  Alternatively you
can simply enter the text part of the image name, and enter the extension
and digits yourself later.

    There are some important things to note with image sequences.

    - All images in a sequence must share the same number of digits
       such as:   pic001.iff  pic020.iff  pic325.iff
       In this case the digit number is 3 and the extension is .iff

    - Lightwave uses the last picture it can for all frames until a new
      one is found.  Thus for the above, pic001.iff is used from frames
      1 to 19.  Then at frame 20 pic020.iff is used until frame 324 and
      so on.

    - It is easier to simply select one of the files since you simply
      enter the name such as "pic" when loading a sequence you must
      manually enter the number of digits and extension.

========================================================================
              SECTION 4 - Lightwave Layout - Animation
========================================================================

1] I move my objects into position, but they keep "forgetting" where
   they were.

    In order for Lightwave to remember the postion, rotation, size other
other settings of objects during an animation you must make a keyframe
for that object.  To do so, select "Create Key".  Then select either
"Selected Item" or "All" depending on if you want to create a keyframe
for just the selected item or for all items.

   An improtant note: Even if you create a key frame for an object
Light or Camera, if you go back later and alter it's position, rotation
or other setting you must choose "Create Key" again.  Otherwise the
item will be set back to it's last "key" setting.

    This is why there is no UNDO function in Layout.  If you wish to
undo a change, simply go back or forth to another frame without
choosing "Create Key".  When you return to the frame, the item will be
reset to it's last settings.

    HOWEVER, if you want to be able to simply change an item that
already has a keyframe set without having to select "Create Key" again
for that frame, choose "Auto Key Adjust" from the Option menu in Layout.
This sets Layout to always remember the last settings for an item when
you alter it in a keyframe.  Note that the only undo ability will be to
reload a saved scene in this case.

------------------------------------------------------------------------

2] I have problems setting bones for my object.  My object keeps
   resizing or changing.

   In order to place bones for your object there are 4 basic steps.

   1. Add a bone
   2. Position the bone, and resize it using REST LENGTH not size.
   3. Create a Keyframe for the bone
   4. Press 'r' to active it and set it's rest information.

   There are 2 important notes.  If you want to change the size of
the bone for setup, use the "Rest Length" operation, not the "Size"
operation.  Otherwise when you press 'r' the object will suddenly
grow or shrink.

    Also, you should set a keyframe for the bone, or it will be reset
to it's default settings.

TIP for adding Child Bones:

    Because child bones are added relative to their parent bones, it's
often easier to add 1 parent bone first and get it setup to the proper
size and rotation.  Then go and add a child bone or bones.  If you
do this, the child bones size will probably be more appropriate.  On
the other hand if you add all your bones at once, you will have to set
the Rest Length for each.

------------------------------------------------------------------------

3] Can I click on an item to select it in Layout?

    Yes, you should press the SHIFT key and click on objects origin.
The origin is the location of the object that rotations take place
around.  Note this is in Lightwave 4.0 and you must click fairly close
to that position.

------------------------------------------------------------------------

4] Whenever I create a preview wireframe animation, my objects don't
   show up, but I can see Lightsources and paths.

    In the Windows version of Lightwave, some display cards have a
problem with their video driver software.  This causes objects to
not appear when you create a wireframe preview.  To remedy this you
should contact your display card manufacturer to obtain a new version
of your graphics drivers.

------------------------------------------------------------------------

5] How can I copy a keyframe for an item?

    Go to the key frame you wish to copy from.  Select "Create Key".
Now, change the frame number for the create key dialog to the frame
you wish to copy to.  Click Ok.

    Note that the spline control settings are NOT copied.  ie: tension
continuity and bias are not copied over.

------------------------------------------------------------------------

6] Quick Spline Control Tips

    Spline controls are used to get better control at object motion and
other envelopes in Lightwave.  The following is a quick guide to them.
One thing to remember is that spline controls effect the action at that
point or keyframe.

    Tension:     + Positive = Items moves faster through point
                 - Negative = Items moves slower through point

    Continuity:  + Positive = Smoother curve point
                 - Negative = Sharper bounce at point

    Bias:        + Positive = Slack/more data after curve
                 - Negative = Slack/more data before curve

    Linear:      Straight motion from previous keyframe to current.  Other
                 settings may still affect motion up to the next key.

For example:

    To make an object slow down at a keyframe you would want to
have a negative Tension.  To make a ball bounce with a sharp change of
direction at a keyframe you will want a negative Continuity.  To make
it accelerate at that bounce frame you will want a postive tension
at the frame as well, and probably a negative one at the start of the
top of the fall.

------------------------------------------------------------------------

7] I have problems trying to position objects with my WACOM tablet!

    Those with WACOM tablets may have noticed that trying to move
objects in Layout around doesn't work.  This is because Lightwave keeps
reseting the mouse position and performs the move based on the relative
change of the mouse.  However the WACOM tablets report position in
absolute mode.

    The solution is to set the tablet into relative mode.  I think the
ARTZ-II has a button for this on the tablet itself...though check your
WACOM docs to be sure.

    Note that with Version 5.0 in Layout there is now a "Input Device"
button in the Options|General Options menu.  Selecting Tablet instead of
Mouse should make the tablet work.

------------------------------------------------------------------------

8] How come when I rotate objects or bones in a hierarchy they don't
   rotate or move the way I expect?

    Lightwave does not handle local transofrmations for an object in a
hierarchy as one might expect.  What happens is the object moves in
the transformed coordinate system.  However the direction it moves
is based on what view you are using and where the mouse is going as if
it were not transformed.

    This means in a Front view, moving the mouse to the right will make
an object move in it's positive X axis.  If it has a parent that is
rotated, it won't move exactly in the direction of the mouse, but rather
in the plus X axis direction of the parent.

    You can hold down the control key to get local positioning for child
objects though there is no way to get local rotations.

------------------------------------------------------------------------

9] How can I make objects that flow around and through complex turns?

    At first it might seem difficult to get an object to flow around
other objects.  For example little arrows moving around the inside
of a copy machine showing how it works, or paper going through rollers.
However with the use of bones and morphing it is actually pretty easy.

    For an example suppose you had a long piece of paper and wanted it
to progress through a series of rollers.  Model a square with enough
segments that it can bend smoothly.  Then in Layout add bones starting
at one end, and then progressing down the length of the paper object.

    The bones should be small enough that you will be able to arc them
smoothly.  Create keyframes at frame 0 for these bones and make them
active.  Now that these bones are set in their rest positions, move
them so that they align to a path through the rollers.  Keyframe the
moved bones at frame 1.

    Note that you can go back to frame 0 to tweak the inital rest
position if needed.  For the actual animation the bones from frame 1
(and on) are used.

    At this point the paper object should be conformed to one possible
frame through the rollers in frame 1.  You might think you would have
to move and keyframe the bones object to animate it.  However with a
morph you can accomplish the same thing in a few easy steps.

    In modeler load your paper object.  Shift it "back" along the long
part of the paper.  ie: if your paper is lying flat in the X-Z plane
and is long along the X axis, shift it along the X axis.  Save this
repositioned object under a new name.

    In layout load the transformed paper in.  Set the morph target of
the boned object to be the moved object.  Then morph from one to the
other.

    What happens is the object always conforms to the bones.  As the
morph occurs the polygons progress left to right but still keep their
bone structure.  This causes them to move but to bend around following
a "bone path".

------------------------------------------------------------------------

10] I am having problem with the AVI saver and Windows 95!

(This section is unavailable until I am authorized to add it.)

------------------------------------------------------------------------

11] Lightwave crashes when trying to render animation files out!

(This section is unavailable until I am authorized to add it.)

    Lightwave 5.0 does not have this problem.

------------------------------------------------------------------------

12] When I load a large object, I find I can't position the camera or
    other objects with enough precision.

    Lightwave uses the grid size to determine the amount something
changes when you are positioning it.  When a large object is loaded
Lightwave will automatically increase the grid size to help you position
it.  To get more precision decrease the grid size.  This is in the
Options panel, then the Layout View Tab then Grid Square Size.

    In the same way if you are trying to move an object farther and it
is not moving fast enough you can increase the grid size.

------------------------------------------------------------------------

13] I am trying to use Inverse Kinematics (IK) but it doesn't seem to
    work correctly.

    When you create an IK chain the last object may appear not to reach
properly for the goal object.  This is because what is actually used
in the "reach" is the pivot point of the last object.

    For example in an arm, the upper arm connects to the lower arm
connects to the hand. Usually the pivot point for the hand is at the
wrist.  If you used IK on this chain the arm would move and reach for
the goal.  However the hand might seem to dangle or bend strangely.
This is because the last point reaching for the goal is at the wrist.

    To correct this add a null object after the last object in the IK
hierarchy.  In this case you would want it positioned at the end of
the hand, where the fingers would be.  Now the Null Object is the last
object trying to reach toward the goal.  This makes the hand rotate in
line toward the goal as you would expect.

    Another common problem with IK is keyframes.  Inverse Kinematics
is basically a positioning tool.  Until you move the goal object the
chain will not move.  Once it looks the way you desire, you still need
to keyframe every object in the chain.

    The exception to this is the "Full-time IK" feature available in
Lightwave 5.0.  In this case the goal object can simply be moved and
keyed and the chain will always try to reach for the goal.

    In general however full time IK may not give the desired results.
This is because typically there are any number of ways to rotate a chain
to reach for the goal.  On each frame the Full-time IK may pick a
different rotation for objects which results in the chain seeming to
jump.  To get around this simply use IK to position the objects at
keyframes and let Lightwave create smooth inbetweens.

------------------------------------------------------------------------

14] I have turned on joint compensation and muscle flexing for some
    bones but nothing seems to happen.

    In Lightwave 5.0 some new bone features were added.  These include
joint compensation and muscle flexing.  Joint compensation help stop
the pinching of the object where 2 bones bend.  With muscle flexing you
can make part of an object bulge when you bend a bone, similar to
bending your forearm and having your bicept muscle bulge.

    If you are having problems getting any results with these features
note the following:

    Suppose you have an arm type object, say a simple cylinder.  Add a
bone and a child bone.  ie: if a +------- is a bone:

     +----------+----------

     (say the one on the left is the upper arm, and the one on the right
is the lower arm, and they are centered throughout the length of the
cylinder.

          \
            \
              \
    +----------+

    Now if you bend the lower arm as above and try to set "Joint
Compensation" and "Muscle Flexing for Parent" for the lower arm it
won't work!

    The problem is the lower arm must have a position offset relative
to the upper arm.  In fact this is what you need if you want it to bend
properly anyhow.  Position the pivot point of the lower arm bone at
the top part of the cylinder/lower arm.  For example:

                                                      \
                                                        \
                                                          \
                 +----------       and                     +
      +----------                               +----------

    This will work.  In this case you want to set "Joint Compensation"
and "Muscle Flexing for Parent" for the lower arm bone.  Note that by
offseting the lower arm bone you will probably need to increase its
strength or add a child bone to help grab the bottom part of the lower
arm.

    Note also that it seems you have to use Pitch rotation on the child
bone to get the proper results.

========================================================================
END OF LW3D-FAQ


--
| Mike Comet - [e-mail] - Case Western Reserve University
| Visit my homepage with Animation, Graphics, Lightwave 3D FAQ at:
| http://cnswww.cns.cwru.edu/php/comet/