Author Topic: "Tip: AutoCAD's Big Problem"  (Read 10767 times)

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Mark

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"Tip: AutoCAD's Big Problem"
« on: September 18, 2006, 12:27:06 PM »
Quote from: cadalyst
For years, AutoCAD hasn't worked well with large coordinates in civil engineering and survey drawings. Here, we offer some workarounds.

[ http://gis.cadalyst.com/gis/article/articleDetail.jsp?id=370189 ]
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Greg B

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Re: "Tip: AutoCAD's Big Problem"
« Reply #1 on: September 18, 2006, 12:36:21 PM »
Nice article....

Question...

Once a drawing is put together with survey data, can you not move the drawing closer to 0,0?

Dinosaur

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Re: "Tip: AutoCAD's Big Problem"
« Reply #2 on: September 18, 2006, 12:42:57 PM »
TEASER !  I was hoping for a workaround that really worked around without a series of "buts" involved.  This is part of what was being discused HERE last week and what prompted THIS kind comment from Greg about communication and cooperation between disciplines.

CADaver

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Re: "Tip: AutoCAD's Big Problem"
« Reply #3 on: September 18, 2006, 01:02:09 PM »
Once a drawing is put together with survey data, can you not move the drawing closer to 0,0?
GGGRRRRRR.................

Maverick®

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Re: "Tip: AutoCAD's Big Problem"
« Reply #4 on: September 18, 2006, 01:07:11 PM »
GGGRRRRRR.................

Beans for breakfast?  :?

Slim©

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Re: "Tip: AutoCAD's Big Problem"
« Reply #5 on: September 18, 2006, 02:37:51 PM »
Once a drawing is put together with survey data, can you not move the drawing closer to 0,0?

Never, Never, Never.....  :pissed: :pissed: :pissed:
I drink beer and I know things....

jonesy

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Re: "Tip: AutoCAD's Big Problem"
« Reply #6 on: September 18, 2006, 02:48:03 PM »
Greg, I dont know if it is the same "over there" but here in the UK all our maps tile together with a common 0,0. If the drawing was moved closer to the 0,0 the user wouldnt be able to get any true grid referencing data from it, or of the boundary of the job needed to be extended, the user wouldnt know the correct insertion point.

This is just one of the reasons we would never move the drawing closer :-)
Thanks for explaining the word "many" to me, it means a lot.

Mark

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Re: "Tip: AutoCAD's Big Problem"
« Reply #7 on: September 18, 2006, 02:55:47 PM »
Nice article....

Question...

Once a drawing is put together with survey data, can you not move the drawing closer to 0,0?

No because all our other data is on the same coordinate system, i.e. aerials, land records, utility information and all kinds of GIS data.
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Greg B

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Re: "Tip: AutoCAD's Big Problem"
« Reply #8 on: September 18, 2006, 03:37:22 PM »
Nice to get answers vs. threats....

Dent Cermak

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Re: "Tip: AutoCAD's Big Problem"
« Reply #9 on: September 18, 2006, 10:04:10 PM »
You can move it all you want. When you ask me to stake your building out in the field, please take no offense when I kick your booday. :pissed: :pissed:
There should be a requirement that ALL Archi types take algebra with great emphasis on plotting equations on an x,y axis. Then someone could whisper to them, "Pssst!! Dude!! it's called coordinate geometry for a reason!!".
Greg , you have asked this question before. Now, I am asking questions and not trying to be ugly or rude. Do you truly not see a problem with moving a project and maybe rotating it to make it fit the sheet better?
I do not mind a dview twist, but a rotation undoes EVERYTHING I have done.
What is the advantage of taking the drawing off of my state plane coordinates and moving them
closed to 0,0"? It does not make the drawing any smaller.
Should you need to use my surface for some of your comps, what happens then ? Surfaces do not move.
If you move the drawing and then I bring in my point file, the two are WAY far apart. I work at N2,000,000. E1,000,000 and you want to work at 0,0. See the problem? You cannot take your drawing and put it back on the ground with any accuracy, especially if you do like most do and leave the "Control Points" at their original location.
That's why the surveyor gets upset. Today, everything we do is based on state plane coordinates from GPS observations. Everything we do is "relative" to all of our other drawings.
Our state regulations require a "positional accuracy" of 0.05'. We work hard and spend a lot of money on equipment to meet that tolerance. When you throw it out the window we get a little peeved.


Mark, I just went and read that article. I have been wokring in State Plane Coordinates mostly since 1988 and nothing but State Plane Coordinates since 1998 and I have not run into any of the problems that they mention in the article. My hatches work fine, The only time the trim command gets squirrely is when I am dealing with polylines that have been spline fit. What am I doing wrong???  :|
« Last Edit: September 18, 2006, 10:33:03 PM by Dent Cermak »

CADaver

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Re: "Tip: AutoCAD's Big Problem"
« Reply #10 on: September 19, 2006, 08:28:38 AM »
Mark, I just went and read that article. I have been wokring in State Plane Coordinates mostly since 1988 and nothing but State Plane Coordinates since 1998 and I have not run into any of the problems that they mention in the article. My hatches work fine, The only time the trim command gets squirrely is when I am dealing with polylines that have been spline fit. What am I doing wrong???  :|
The problem with hatches is NOT the large coordinates, but the way some hatches are defined.  With large coordinates the hatches that "look' right at smaller coordinates display the inherant inaccuracy of its definition.

Below is a rubble pattern hatch that "looks" fine at smaller coordinates.  The rubble objects "look" like they close, but as the distance from the origin gets larger and larger the small differences in the angles and distances begin to diverge more and more.  The 5 decimal place wide gap is invisible close to the origin, but 5 million units farther away the gap is now several feet, destroying the display, "look" of the hatch.

Code: [Select]
*Rubble
45.000000,0.700328,0.021647,0.707107,0.707107,0.170013,-1.244200
0.000000,0.530315,0.021647,0.000000,1.000000,0.170013,-0.829987
315.000000,0.219239,0.332723,0.707107,0.707107,0.439927,-0.974286
270.000000,0.219239,0.502736,0.000000,1.000000,0.170013,-0.829987
225.000000,0.339457,0.622953,0.707107,0.707107,0.170013,-1.244200
180.000000,0.509470,0.622953,0.000000,1.000000,0.170013,-0.829987
135.000000,0.820545,0.311878,0.707107,0.707107,0.439927,-0.974286
90.000000,0.820545,0.141865,0.000000,1.000000,0.170013,-0.829987
180.000000,0.134669,0.977502,0.000000,1.000000,0.055106,-0.944894
224.996430,0.079563,0.977502,0.707151,0.707063,0.097163,-1.316963
270.000000,0.010854,0.908802,0.000000,1.000000,0.055106,-0.944894
315.001739,0.010854,0.853695,0.707128,0.707085,0.069826,-1.344345
0.000000,0.060230,0.804322,0.000000,1.000000,0.055106,-0.944894
44.996430,0.115337,0.804322,0.707151,0.707063,0.097163,-1.316963
90.000000,0.184045,0.873023,0.000000,1.000000,0.055106,-0.944894
135.001739,0.184045,0.928129,0.707128,0.707085,0.069826,-1.344345
90.000000,0.990547,0.430273,0.000000,1.000000,0.061995,-0.938005
134.996430,0.990547,0.492268,0.707063,0.707151,0.109308,-1.304994
180.000000,0.913260,0.569565,0.000000,1.000000,0.061995,-0.938005
225.001739,0.851265,0.569565,0.707085,0.707128,0.078554,-1.335702
270.000000,0.795720,0.514017,0.000000,1.000000,0.061995,-0.938005
314.996430,0.795720,0.452022,0.707063,0.707151,0.109308,-1.304994
0.000000,0.873008,0.374725,0.000000,1.000000,0.061995,-0.938005
45.001739,0.935003,0.374725,0.707085,0.707128,0.078554,-1.335702
180.000000,0.206022,0.302800,0.000000,1.000000,0.084726,-0.915274
224.996430,0.121296,0.302800,0.707151,0.707063,0.149388,-1.264738
270.000000,0.015656,0.197173,0.000000,1.000000,0.084726,-0.915274
315.001739,0.015656,0.112447,0.707128,0.707085,0.107358,-1.306813
0.000000,0.091572,0.036536,0.000000,1.000000,0.084726,-0.915274
44.996430,0.176298,0.036536,0.707151,0.707063,0.149388,-1.264738
90.000000,0.281938,0.142162,0.000000,1.000000,0.084726,-0.915274
135.001739,0.281938,0.226889,0.707128,0.707085,0.107358,-1.306813
45.001739,0.171820,0.552838,0.707085,0.707128,0.087283,-1.326974
0.000000,0.102937,0.552838,0.000000,1.000000,0.068883,-0.931117
314.996430,0.017061,0.638724,0.707063,0.707151,0.121453,-1.292848
270.000000,0.017061,0.707607,0.000000,1.000000,0.068883,-0.931117
225.001739,0.078778,0.769327,0.707085,0.707128,0.087283,-1.326974
180.000000,0.147661,0.769327,0.000000,1.000000,0.068883,-0.931117
134.996430,0.233536,0.683441,0.707063,0.707151,0.121453,-1.292848
90.000000,0.233536,0.614558,0.000000,1.000000,0.068883,-0.931117
180.000000,0.869347,0.991291,0.000000,1.000000,0.137766,-0.862234
224.996430,0.731581,0.991291,0.707151,0.707063,0.242907,-1.171219
270.000000,0.559809,0.819541,0.000000,1.000000,0.137766,-0.862234
315.001739,0.559809,0.681775,0.707128,0.707085,0.174565,-1.239605
0.000000,0.683249,0.558342,0.000000,1.000000,0.137766,-0.862234
44.996430,0.821015,0.558342,0.707151,0.707063,0.242907,-1.171219
90.000000,0.992787,0.730093,0.000000,1.000000,0.137766,-0.862234
135.001739,0.992787,0.867859,0.707128,0.707085,0.174565,-1.239605
180.000000,0.428784,0.978283,0.000000,1.000000,0.137766,-0.862234
135.000000,0.526200,0.880867,0.707107,0.707107,0.137766,-1.276448
90.000000,0.526200,0.743101,0.000000,1.000000,0.137766,-0.862234
45.000000,0.428784,0.645686,0.707107,0.707107,0.137766,-1.276448
0.000000,0.291018,0.645686,0.000000,1.000000,0.137766,-0.862234
315.000000,0.193603,0.743101,0.707107,0.707107,0.137766,-1.276448
270.000000,0.193603,0.880867,0.000000,1.000000,0.137766,-0.862234
225.000000,0.291018,0.978283,0.707107,0.707107,0.137766,-1.276448




Greg B

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Re: "Tip: AutoCAD's Big Problem"
« Reply #11 on: September 19, 2006, 10:23:52 AM »
Dent,

I did NOT know that survey's were based from a state set point.  I take that back, I kinda knew it.

I know understand why survey's are done the way they are.

I will rotate a civil drawing to easier place my building, and at the time did not know of a couple of feature of DataCAD that rotate my cursor.  When I did rotate the building, when I was done, I would rotate it back.  Now that I can rotate my cursor, it is not such a big deal any longer.

As for moving a drawing.  I understand now how it affects civil drawings.  It's nice when someone takes a minute to explain how it works vs.

GGGRRRRRR.................

Never, Never, Never.....  :pissed: :pissed: :pissed:

Is all your data based on GPS?

LE

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Re: "Tip: AutoCAD's Big Problem"
« Reply #12 on: September 19, 2006, 10:53:23 AM »
Including is a partial drawing from a residential subdivision project, it was drawn accurately and it is needed to create some land usage plan, and all the lots are required to be closed polylines.

Try with the command boundary, bhatch, and if the HPGAPTOL system variable is available or change the ORIGIN of your UCS, if you know how to change the ray casting (vector used by the bpoly function) and while in there make your coordinates with less precision, you will note that it is almost impossible to do it in vanilla AutoCAD.

And demonstrate what that article is referring.
« Last Edit: September 20, 2006, 09:50:59 AM by LE »

Dent Cermak

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Re: "Tip: AutoCAD's Big Problem"
« Reply #13 on: September 19, 2006, 01:15:27 PM »
Dent,

I did NOT know that survey's were based from a state set point.  I take that back, I kinda knew it.

I know understand why survey's are done the way they are.

I will rotate a civil drawing to easier place my building, and at the time did not know of a couple of feature of DataCAD that rotate my cursor.  When I did rotate the building, when I was done, I would rotate it back.  Now that I can rotate my cursor, it is not such a big deal any longer.

As for moving a drawing.  I understand now how it affects civil drawings.  It's nice when someone takes a minute to explain how it works vs.

GGGRRRRRR.................

Never, Never, Never.....  :pissed: :pissed: :pissed:

Is all your data based on GPS?



We are not based on a "state set point". We use GPS to establish lat/long and state plane coordinates on all of the control points. So, yes, all of our data is based on GPS. It's much more accurate and much quicker than running a 3 mile closed loop traverse. (out in the county, quality control points are few and far between.)

If Datacad can run lisp routines, there is one on this site called "Planview" that will solve your problem. It will let you twist everything as much as you want and still have horizontal crosshairs. AND the data base is maintained. If you cannot find it let me know and I will send you a copy.I think Keith wrote it back in his lucid days. :evil:

Greg B

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Re: "Tip: AutoCAD's Big Problem"
« Reply #14 on: September 19, 2006, 01:21:13 PM »
That's for the offer Dent.  DataCAD does not use lisp.  They use a system called DCAL (DataCAD Applications Language) and recent started DCAL for Delphi.

If I had the time, I'd love to get involved in this programing language to help customize DataCAD.

Dent Cermak

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Re: "Tip: AutoCAD's Big Problem"
« Reply #15 on: September 20, 2006, 09:04:40 AM »
Wonder if we have any DCAL gurus here that might could convert the lisp routine for you?  :ugly:

Greg B

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Re: "Tip: AutoCAD's Big Problem"
« Reply #16 on: September 20, 2006, 09:54:55 AM »
Funny...

I know I had said in another thread that after talking with our civil guys we figured out how to better exchange information.

They are going to wblock just the information we need.

We need their information to be accurate and to make our drawings look pretty.   ^-^

LE

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Re: "Tip: AutoCAD's Big Problem"
« Reply #17 on: September 20, 2006, 10:32:15 AM »
Below is a rubble pattern hatch that "looks" fine at smaller coordinates.  The rubble objects "look" like they close, but as the distance from the origin gets larger and larger the small differences in the angles and distances begin to diverge more and more.  The 5 decimal place wide gap is invisible close to the origin, but 5 million units farther away the gap is now several feet, destroying the display, "look" of the hatch.

Hola Randy;

You can make a call to the command UCS using the Origin option (that it is not documented the directly access):

To define a temporary origin closer to the hatchable area.

Command: UCS
Current ucs name:  *WORLD*
Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World]
<World>: Origin
Specify new origin point <0,0,0>:

Then, call the hatch command and after that call to the UCS Previous

Or, you can use the SNAPBASE (after autocad 2005, I think the name has changed - do not remember what it is) system variable and define the location closer to the hatchable area.

That's how in most of the cases it will work.

HTH

Dinosaur

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Re: "Tip: AutoCAD's Big Problem"
« Reply #18 on: September 20, 2006, 10:33:09 AM »
Dent, I searched but can't find that routine.  Do you have a copy of it in the Lily Pond?

CADaver

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Re: "Tip: AutoCAD's Big Problem"
« Reply #19 on: September 20, 2006, 11:44:32 AM »
Hola Randy;

You can make a call to the command UCS using the Origin option (that it is not documented the directly access):
....
Or, you can use the SNAPBASE (after autocad 2005, I think the name has changed - do not remember what it is) system variable and define the location closer to the hatchable area.

Hola mi amigo, Como estas?

Thanks Luis, I've used the UCS workaround for some time.  My point was that the problem was not with large coordinates, but with the way hatches were defined.

Another option some may not know is that hatches already placed can be repaired. AFTER changing the UCS, use the properties box to change the hatch scale to itself, IE, if it's 12.375, highlight the number and key in 12.375 and the hatch will rebuild using the current UCS..  MATCHPROP works well for this also.

sinc

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Re: "Tip: AutoCAD's Big Problem"
« Reply #20 on: September 20, 2006, 12:24:52 PM »

Or, you can use the SNAPBASE (after autocad 2005, I think the name has changed - do not remember what it is) system variable and define the location closer to the hatchable area.


Yep, setting a SNAPBASE to something near your site fixes the hatch problem (for all newly-created or edited hatches, anyway).

In newer versions of Autocad, each hatch object has its own origin point.  This origin point can be relative to the center or a corner of the hatch, or it can be any point you pick.  The origin of newly-created hatches is controlled by the HPORIGINMODE and HPORIGIN system variables.

The way I usually use it is to set HPORIGINMODE so that new hatches go in using the HPORIGIN as their origin.  Then I set the HPORIGIN to a point in/near my job site before creating any hatches.  That makes adjacent hatches of the same type to line up with each other, which they don't do if they each have different origins.
« Last Edit: September 20, 2006, 06:29:05 PM by sinc »

LE

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Re: "Tip: AutoCAD's Big Problem"
« Reply #21 on: September 20, 2006, 12:44:03 PM »
Hola mi amigo, Como estas?

Muy bien, gracias  :-) (doing fine thanks)

Quote
Another option some may not know is that hatches already placed can be repaired. AFTER changing the UCS, use the properties box to change the hatch scale to itself, IE, if it's 12.375, highlight the number and key in 12.375 and the hatch will rebuild using the current UCS..  MATCHPROP works well for this also.

Yep... that would work too.... thanks.

CADaver

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Re: "Tip: AutoCAD's Big Problem"
« Reply #22 on: September 20, 2006, 05:24:50 PM »
Hola mi amigo, Como estas?
Muy bien, gracias  :-) (doing fine thanks)

De nada, yo tambien. ;)