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Mr T
4th Oct 2004, 05:07 pm
Please read this first, yes it is long :lol: .
I need to fix the formating :oops:

AutoCAD 2000 3D FAQ

This FAQ answers the following questions:

Q1: How do I speed up 3D redraws in SHADEMODE and 3DORBIT?
Q2: Why does the model change from shaded to wireframe to boxes while I
manipulate the view in 3DORBIT?
Q3: How do I set the center of rotation for 3DORBIT?
Q4: Do I need to download a Heidi driver for my card to enable 3D hardware
accleration?
Q5: Which video cards are capable of hardware accelerated 3D in AutoCAD 2000?
Q6: Why do my objects disappear when I enable materials?

------------------------------------------------------------- ------------------
-
Q1: How do I speed up 3D redraws in SHADEMODE and 3DORBIT?

1. Enable 3D hardware acceleration. Installing a video card with robust
hardware-acclerated OpenGL 1.1 support will dramatically increase 3D
performance. If you do have one, enable hardware acceleration through
Tools->Options->System->Current 3D Graphics
Display->Properties->Acceleration->Hardware, and select "wopengl6.hdi".
2. Set the DISPSILH sysvar to 0.
3. Turn off dynamic tessellation through Tools->Options->System->Current 3D
Graphics Display->Properties->Dynamic Tessellation.
4. Select only those entities you wish to view before invoking 3DORBIT.
3DORBIT will only display what you selected. If you do not select any
entities, 3DORBIT will display the entire model.

----------------------------------------------------------------- --------------
-
Q2: Why does the model change from shaded to wireframe to boxes while I
manipulate the view in 3DORBIT?

3DORBIT will maintain a minimum frame rate by drawing the model as a wireframe
or bounding boxes, if necessary, while you are manipulating the view.

You can turn this off through Tools->Options->System->Current 3D Graphics
Display->Properties->Adaptive Degradation. Uncheck Wireframe and Bounding Box,
and set Maintain Speed to 1 FPS.

Alternatively, you can use Continuous Orbit (3DCORBIT), which never uses
Adaptive Degradation.

----------------------------------------------------------- --------------------
-
Q3: How do I set the center of rotation for 3DORBIT?

There are three ways to set the center of rotation for use with the 3DORBIT
command, depending on what you want to rotate about:

1. If you want to rotate about the MODEL CENTER, invoke 3DORBIT, then select
More->Zoom Extents from the right-click menu.
2. If you want to rotate about an ENTITY or ENTITY SET, select the entity or
entities, invoke 3DORBIT, then select More->Zoom Extents from the right-click
menu. At this point, you can orbit about your selected entity or entity set.
To view the entire model while orbiting about the selected entity or entities,
exit then re-enter 3DORBIT.
3. If you want to rotate about a POINT, invoke CAMERA, accept the default
position, and then type or select the target point (using OSNAP can be handy
here). Then invoke 3DORBIT.

--------------------------------------------------------------- ----------------
-
Q4: Do I need to download a Heidi driver for my card to enable 3D hardware
accleration?

You do not need to download any Heidi driver to enable 3D hardware acceleration
in AutoCAD 2000. As long as you have a video card with robust
hardware-acclerated OpenGL support, and you have 3D hardware accleration
enabled, you will be ready to go.

-------------------------------------------------------------------- -----------
-
Q5: Which video cards are capable of hardware accelerated 3D in AutoCAD 2000?

While we can't make any specific card recommendations, we can say that a robust
OpenGL driver is required. Specifically, the card should include an OpenGL 1.1
ICD (Installable Client Driver). Some cards will mention OpenGL support
through an MCD, MiniGL, or QuakeGL. These cards are generally not capable of
providing hardware accelerated 3D in AutoCAD 2000.

Video card manufacturers often update their OpenGL drivers with bug fixes and
performance enhancements. If you are having trouble which seems video-related,
visit your card manufacturer's website for their latest OpenGL drivers. If
you are still having trouble, post to this newsgroup and we'll try to help.

------------------------------------------------------------------ -------------
-
Q6: Why do my objects disappear when I enable materials?

3DORBIT and SHADEMODE support material colors, but not material textures (this
includes bitmaps, bumpmaps, and the 3d textures granite, marble and wood).
Many materials with textures have underlying black colors, causing the object
to be drawn in black and seemingly disappear. You can fix this through the
RMAT command: select the material in question, choose Modify, then set
Color/Pattern, Ambient, and Reflection to a lighter color.




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

Reply From: [Autodesk], Erik Larsen
Date: Jul/14/99 - 20:58 (GMT)

Re: AutoCAD 2000 3D FAQ
AutoCAD 2000 3D FAQ
June-July 1999

This FAQ answers the following questions:

Q1: How do I speed up 3D redraws in SHADEMODE and 3DORBIT?
Q2: Why does the model change from shaded to wireframe to boxes while I
manipulate the view in 3DORBIT?
Q3: How do I set the center of rotation for 3DORBIT?
Q4: Do I need to download a Heidi driver for my card to enable 3D hardware
accleration?
Q5: Which video cards are capable of hardware accelerated 3D in AutoCAD 2000?
*Q6: Why is my 3D video card unable to accelerate 3D at 1600x1200 resolution?
*Q7: How can I make hidden lines display more accurately in hardware
acceleration mode?
Q8: Why do my objects disappear when I enable materials?
*Q9: Why does my drawing become dark when I enable materials?

*New this release.

--------------------------------------------------------------- ----------------
-
Q1: How do I speed up 3D redraws in SHADEMODE and 3DORBIT?

1. Enable 3D hardware acceleration. Installing a video card with robust
hardware-acclerated OpenGL 1.1 support will dramatically increase 3D
performance. If you have a video card with this capability, you can enable
hardware acceleration through Tools->Options->System->Current 3D Graphics
Display->Properties->Acceleration->Hardware, and select "wopengl6.hdi".
2. Set the DISPSILH sysvar to 0.
3. Turn off dynamic tessellation through Tools->Options->System->Current 3D
Graphics Display->Properties->Dynamic Tessellation.
4. Select only those entities you wish to view before invoking 3DORBIT.
3DORBIT will only display what you selected. If you do not select any entities
before invoking 3DORBIT, 3DORBIT will display the entire model.
5. Try running at a lower desktop resolution. For example, if you are running
at 1600x1200, try running at 1280x1024.

------------------------------------------------------------- ------------------
-
Q2: Why does the model change from shaded to wireframe to boxes while I
manipulate the view in 3DORBIT?

3DORBIT will maintain a minimum frame rate by drawing the model as a wireframe
or bounding boxes, if necessary, while you are manipulating the view.

You can turn this off through Tools->Options->System->Current 3D Graphics
Display->Properties->Adaptive Degradation. Uncheck Wireframe and Bounding Box,
and set Maintain Speed to 1 FPS.

Alternatively, you can use Continuous Orbit (3DCORBIT), which never uses
Adaptive Degradation.

----------------------------------------------------------- --------------------
-
Q3: How do I set the center of rotation for 3DORBIT?

There are three ways to set the center of rotation for use with the 3DORBIT
command, depending on what you want to rotate about:

1. If you want to rotate about the model center, invoke 3DORBIT, then select
More->Zoom Extents from the right-click menu.
2. If you want to rotate about an entity or entity set, select the entity or
entities, invoke 3DORBIT, then select More->Zoom Extents from the right-click
menu. At this point, you can orbit about your selected entity or entity set.
To view the entire model while orbiting about the selected entity or entities,
exit then re-enter 3DORBIT.
3. If you want to rotate about a point, invoke CAMERA, accept the default
position, and then type or select the target point (using OSNAP can be handy
here). Then invoke 3DORBIT.

--------------------------------------------------------------- ----------------
-
Q4: Do I need to download a Heidi driver for my card to enable 3D hardware
accleration?

You do not need to download any Heidi driver to enable 3D hardware acceleration
in AutoCAD 2000. As long as you have a video card with robust
hardware-acclerated OpenGL 1.1 support, and you have 3D hardware accleration
enabled, you will be ready to go.

-------------------------------------------------------------------- -----------
-
Q5: Which video cards are capable of hardware accelerated 3D in AutoCAD 2000?

While we can't make any specific card recommendations, we can say that a robust
OpenGL driver is required. Specifically, the card must include an OpenGL 1.1
ICD (Installable Client Driver). Some cards will mention OpenGL support
through an MCD, MiniGL, or QuakeGL. These cards are generally not capable of
providing hardware accelerated 3D in AutoCAD 2000.

For a good starting point in selecting a 3D video card to use with AutoCAD
2000, try this link:

http://ktx.com/support/html/tested_graphics_cards.html

Video card manufacturers often update their OpenGL drivers with bug fixes and
performance enhancements. If you are having trouble which seems video-related,
visit your card manufacturer's website for their latest OpenGL drivers. If
you are still having trouble, post to this newsgroup and we'll try to help.

------------------------------------------------------------------ -------------
-
*Q7: Why is my 3D video card unable to accelerate 3D at 1600x1200 resolution?

While a 3D video card may be capable of displaying at 1600x1200 desktop
resolution, it may not be capable of accelerating 3D at that resolution. This
is due to the much greater memory requirements of 3D.

The following table shows how much memory your 3D video card must have to
accelerate AutoCAD 3D at a given desktop resolution:

If you need to run With 32 bits of With 24 bits of With 16 bits of
AutoCAD at a desktop color and z-buffer color and z-buffer color and z-buffer
resolution of... accuracy: accuracy: accuracy:
------------------- ------------------ ------------------ ------------------
640x480 3.5 MB 2.6 MB 1.8 MB
800x600 5.5 MB 4.1 MB 2.7 MB
1024x768 9.0 MB 6.8 MB 4.5 MB
1152x864 11.4 MB 8.5 MB 5.7 MB
1280x1024 15.0 MB 11.3 MB 7.5 MB
1600x1200 22.0 MB 16.5 MB 11.0 MB

As you can see from the table above, in order to accelerate 3D in AutoCAD at
1600x1200, you need at least 11 MB on your video card.

What exactly does "32 bits/24 bits/16 bits of color and z-buffer accuracy"
mean?

In order for your 3d video card to accelerate 3d operatons, it needs a certain
amount of memory to display colors and obscure hidden surfaces at each pixel.
The accuracy with which a card can color each pixel varies, but the most common
amounts are 24 bits (displaying 16 million colors) and 16 bits (displaying 65
thousand colors). Similarly, the accuracy with which a card can determine
hidden surfaces (called depth- or z-buffering) also commonly requires 24 or 16
bits per pixel. Additonally, for smooth animation, the card must work on the
next frame while simultaneously displaying the current frame to the user
(called double-buffering). All of these requirements result in much greater
memory requirements for 3D versus 2D.

-------------------------------------------------------------------- -----------
-
*Q7: How can I make hidden lines display more accurately in hardware
acceleration mode?

In hidden line shademode (SHADEMODE H), if you are seeing lines that should be
hidden, try the following workaround. Invoke the 3D clipping planes window
(3DCLIP), enable the front clipping plane, then move the front clipping plane
away from your objects (drag downward in the clipping window). You may want to
zoom extents (ZOOM E) prior to invoking 3DCLIP, to ensure that you can move the
front clipping plane away from all of your objects.

--------------------------------------------------------------- ----------------
-
Q8: Why do my objects disappear when I enable materials?

3DORBIT and SHADEMODE support material colors, but not material textures (this includes bitmaps, bumpmaps, and the 3d textures granite, marble and wood). Many materials with textures have underlying black colors, causing the object to be drawn in black and seemingly disappear. You can fix this through the RMAT command: select the material in question, choose Modify, then set
Color/Pattern, Ambient, and Reflection to a lighter color.

----------------------------------------------------------------- --------------
-
*Q9: Why does my drawing become dark when I enable materials?

The global material used by RENDER is dark by default. When you enable
materials and use SHADEMODE or 3DORBIT, this global material is used. To fix this, invoke the RMAT command, select *GLOBAL* from the list of materials, select Modify, and change Value to 1.0 for each of Color/Pattern, Ambient, and Reflection.

a1harps
6th Oct 2004, 09:46 pm
Yes, definitely helpfull.
By the way, after I cast my vote I was automaticly removed from the
forum and I had to reenter it. Dont think you intended that. Hope the vote went through. Best regards, Frank

Mr T
6th Oct 2004, 11:45 pm
Funny, I just voted there and it went to the results page ?

Nick :lol:

CADbug
16th Feb 2005, 09:42 am
Fantastic !!

Mr T...can u post links to such FAQ related to 2D also, if they are previously posted on Forum!!
i am sure YOU CAN!! :)

CADaver
13th Apr 2006, 05:44 pm
Q3 = 3DORBITCTR

Benson
20th Jul 2006, 06:11 pm
Also good to keep your object data as Excel data rather than using attributes. This means that you don't need to turn the entities into blocks and also the master excel sheet can be linked to accounts - meaning instant cost feed back.

nextvkin
28th May 2007, 04:49 am
Also good to keep your object data as Excel data rather than using attributes. This means that you don't need to turn the entities into blocks and also the master excel sheet can be linked to accounts - meaning instant cost feed back.

Benson,
Can you give us a tip on how to do that?

roof11
23rd Jul 2010, 03:30 pm
nice info from Mr. T

Leon786
18th Jan 2012, 07:47 am
Hi,
Thank you for sharing all information 3D. Mr. T