Author Topic: Flatten 3D Walls  (Read 7967 times)

0 Members and 1 Guest are viewing this topic.

42

  • Bull Frog
  • Posts: 483
Flatten 3D Walls
« on: October 05, 2005, 09:59:39 AM »
When drawing in 2D you can use a lisp routine flatten to reduce all rouge lines back to Z=0. Is there out there a 3D version that will return ADT walls back to Z=0 . We don't want to distroy the walls. An Architect drew some of of the walls with a ucs twisted off the z axis.
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

David Hall

  • Automatic Duh Generator
  • King Gator
  • Posts: 4075
Re: Flatten 3D Walls
« Reply #1 on: October 05, 2005, 10:01:09 AM »
its been a while, but cant you change the wall height to 0?  If so, we should be able to write something if nothing else exists
Everyone has a photographic memory, Some just don't have film.
They say money can't buy happiness, but it can buy Bacon and that's a close second.
Sometimes the question is more important than the answer. (Thanks Kerry for reminding me)

42

  • Bull Frog
  • Posts: 483
Re: Flatten 3D Walls
« Reply #2 on: October 05, 2005, 03:09:47 PM »
No, this model is going to form the basis of a full 3D model so we need the height dimension.Thinking..we couild change the height to 0 and later revert it back to the required height.
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

David Hall

  • Automatic Duh Generator
  • King Gator
  • Posts: 4075
Re: Flatten 3D Walls
« Reply #3 on: October 05, 2005, 03:11:44 PM »
thats what i was thinking, Also, you used to be able to go to a 2D view, (Make a copy of your model before you do this) and EXPLODE the model into a 2d view.  your walls would lose the 3D capability, but as long as you saved the original, this might work
Everyone has a photographic memory, Some just don't have film.
They say money can't buy happiness, but it can buy Bacon and that's a close second.
Sometimes the question is more important than the answer. (Thanks Kerry for reminding me)

42

  • Bull Frog
  • Posts: 483
Re: Flatten 3D Walls
« Reply #4 on: October 05, 2005, 03:37:29 PM »
I think exploding the walls is the wrong move, once exploded we will be unable to revert them to ADT walls..............more thinking...can we replace all walls with simple lines or polylines, run flatten and then convert all lines back to ADTwalls, this second item I know that we can do. Its just converting, adding lines to the walls that will need some thinking,
Sure we could draw lines over the walls but with several hundred wall this will be very laborious.
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

Murphy

  • Guest
Re: Flatten 3D Walls
« Reply #5 on: October 05, 2005, 03:45:12 PM »
You could run through all the walls and change the elevation to 0. This way you wouldn't need to explode anything.
Go to this post to get an idea of what to do in VBA.
I do not have ADT so I can't tell you what you will need to reference.

42

  • Bull Frog
  • Posts: 483
Re: Flatten 3D Walls
« Reply #6 on: October 05, 2005, 03:56:05 PM »
Thats it expolde the walls, run flatten lock..freeze  all but the graph line and use this to recreate the walls.
If you alter the elevation of an ADT object the whole item will move rather that twist about the z axis. A typical wall will start at z=0 and end at z=255mm.
« Last Edit: October 05, 2005, 04:00:25 PM by 42 »
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

Bob Wahr

  • Guest
Re: Flatten 3D Walls
« Reply #7 on: October 05, 2005, 04:26:02 PM »
could you do a 3drotate on it?

Dommy2Hotty

  • Swamp Rat
  • Posts: 1127
Re: Flatten 3D Walls
« Reply #8 on: October 05, 2005, 04:30:40 PM »
CAD Manager Pulldown ~> Explode AEC Objects

But that explodes, thus destroying them, which is what you didn't want to do.  So probably no help... :roll:

42

  • Bull Frog
  • Posts: 483
Re: Flatten 3D Walls
« Reply #9 on: October 05, 2005, 06:30:49 PM »
In an ideal world you are correct the last thing we want to do is explode them. However having thought this through, I think the easiest get of jail card is to explode the wall types in turn, erase all but the graph line(placed on a separate layer) and recreate the walls from the flattened lines. All of the doors and windows can be copied from the offending plan and inserted into the new plan.

Upon further investigation to day it seems that the building had been drawn 15k (9.375 miles) from the origin. This caused errors smaller that 8 decimal places, for all intent an purposes when listed accuracy was reported as 0.0000etc. In the normal case of events, certainally with normal lines you would most likely let it go and no harm done, however with ADT the smallest error with the UCS as noted will prevent the walls cleaning up. We cut and pasted the original drawing into a fresh dwg at 0,0; this cured cured the problem with the out of square lines, but not the ADT walls, these were exploded as noted above.

Is it possible that this is related to the known error that shows up with hatching AR-CONC at a distance from 0,0?
« Last Edit: October 06, 2005, 07:20:37 PM by 42 »
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

42

  • Bull Frog
  • Posts: 483
Re: Flatten 3D Walls
« Reply #10 on: October 14, 2005, 06:58:32 AM »
We received this reply today. Confirms my last post but with all the geeky bits.
Hi Andy,

hmm not as far as I was expecting. I have seen a similar problem when using the OS grid for the UK (which is off the south west coast of cornwall) as the drawing origin. This places objects over 100 million units from the origin. Here is what I found about the problem.


<http://autodesk.blogs.com/between_the_lines/2004/01/more_on_autocad.html>

<http://autodesk.blogs.com/between_the_lines/2003/10/64_bit_computer.html>

<http://autodesk.blogs.com/between_the_lines/2004/01/more_on_64bit_p.html>
This page says "The current 64-bit Precision Limit: Double-precision format - 64-bit data width, 15 to 16 digit precision, 1,000,000,000,000 to 0.0000000000000001"

<http://www.intelcad.com/pages/autocad/>

<http://www.intelcad.com/pages/dwfin/main.htm>
This page has the following quote "AutoCAD standard accuracy is 16 significant digits."

The bottom line is that you get 15/16 decimal points of accuracy. With our big drawings (OS UK 0,0 datum point) you are >100,000,000 mm from the origin. so that's 9dp in front of the decimal point and you have 8 after of which only 6 or 7 are accurate. So the last two digits may change, and obviously this gets worse if the UCS is rotated or the walls are rotated. A wall end point is calculated from its start point, length and angle, as soon as we get further than 1*10^9 from the origin you cant be 100% sure that the least significant digit(s) is/are accurate. And this isn't limited to Autodesk software, most other applications would have the same problem if not worse. This is probably why the Z value is fluctuating, we dont see it with the X+Y as they arent at integer values but at large coords I would expect them all to fluctuate as the "noise" becomes an issue for the last two digits.

Hope this helps

BearSummer
Alastair Mallett Autodesk Certified Professional
Technical Director
Hunters South Architects

BenJones

  • Guest
Re: Flatten 3D Walls
« Reply #11 on: October 31, 2005, 10:56:38 AM »
Not sure that this will help, since it sounds like you have found the answer, but this is what some of my guys have done when running into the problem of drawing in 2d and lines at an angle. They set the wall height to 0.001 in (Imperial units). This way they are still walls with the cleanups, and any hatches. Anything less, we have ran into problems that you have stated like hatch not showing up and wall cleanups not working.