Best way to quickly find a point?

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turtle
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Best way to quickly find a point?

Post by turtle » Tue Jul 27, 2021 7:34 pm

Greetings all this is probably the stupidest question ever but how do I quickly find a 'point' in my drawing?
I need too do this because when attempting to make a hatch I get an error:
Loop 3 not closed at point 1131.9/274.433.
OK the area looks to me to be closed so now I am trying to find this 'not closed' point on my drawing.
I tried 'draw line from two points' figured i'd enter the value the program just gave me;
However when I enter 1131.9/274.433 as the starting point I get the following error:
Unknown command or invalid coordinate or value: "1131.9/274.433"
Numbers may be entered as: "3.142"
Coordinates may be entered as: "1.234,1.234" (absolute) or "@1.234,1.234" (relative) or "10<278.873" (polar) or "@10<278.873" (relative polar)
You may change the number / coordinate format in the application preferences.
I can select 'draw line from two points' and use 1131.9, 274.433 and that works but its not abundantly clear its the point in question.
I have not changed anything in the application preferences.
Thanks in advance
Comments based on Version: 3.26.2 unless otherwise noted.

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andrew
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Re: Best way to quickly find a point?

Post by andrew » Tue Jul 27, 2021 9:41 pm

turtle wrote:
Tue Jul 27, 2021 7:34 pm
I can select 'draw line from two points' and use 1131.9, 274.433 and that works but its not abundantly clear its the point in question.
Yes, that's the open point.

turtle
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Re: Best way to quickly find a point?

Post by turtle » Wed Jul 28, 2021 1:59 am

Thank you for the response Andrew
Is there not a way to highlight or select the points the hatch needs closed?
I often get caught up on hatches.

Like In this attached example, I broke out my problem area out of a huge set of site plans, its the typical hatch that trips me up.

This one keeps getting open points everywhere, yet it all seems connected.
I turn off the 'hatch' layer before trying to add the new hatch but to no avail I get loop not closed.

Also I think the slash in the 'loop not closed' error message is ambiguous, I think it should use whatever coordinate format the user configures or better yet highlight the point.
Thanks in advance for your tips and guidance
--Turtle

EDIT and yes those leaders would be there in the normal drawing
Attachments
why_is_this_not_closed-v2.png
why_is_this_not_closed-v2.png (31.77 KiB) Viewed 1403 times
why_is_this_not_closed-v2.dxf
(611.7 KiB) Downloaded 30 times
Comments based on Version: 3.26.2 unless otherwise noted.

CVH
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Re: Best way to quickly find a point?

Post by CVH » Wed Jul 28, 2021 5:40 am

Hi,

This is what I call a 'problematic bulging polyline' lately.
Presumably originated from a spline.
I am looking into a method to round any given polyline at its corners and face the same issues.

What happens is that QCAD decompose your polyline into arc segments.
At a certain point that can't be done mathematically correct and is leading to minute gaps.
That may occur more the smaller the bulge factor is e.g. 0.001527 and is exponentially.
One can see that zooming in at two things:
- Midpoint markers of bulging segments seems to be off.
- The selected segments for hatching seems to be aside the original polyline.

Selecting segments for your boundary is also problematic there:
- It stops at an intersection with the crossing lines and leaders.
Cutting the already troublesome segments at that point.
- It stops were the pattern of the upper AR-CONC pattern touches the horizontal polyline segment.
What is considered as being buggy.
Such positions where already no longer regarded as snappoints.
*EDIT* Filed FS#2264: https://www.ribbonsoft.com/bugtracker/i ... sk_id=2264

Best way is to duplicate the surrounding shapes and to create a single closed contour.
I do this by default and keep them on a dedicated layer. :wink:

Added layers '_Boundary' & '_Hatch', the one holds a closed boundary, the other a solid hatch.
You can change the solid hatch into something else with the Property Editor.

why_is_this_not_closed-revCVH.dxf
(618.67 KiB) Downloaded 25 times

Workaround:
Selected all surrounding shapes .. Duplicated .. Moved to dedicated layer.
Hide all layers .. View dedicated .. Trim surrounding shapes pair-wise .. Select All .. Polyline from selection.
Create hatch of selection .. View all layers .. Hide dedicated.

Regards,
CVH
Last edited by CVH on Wed Jul 28, 2021 7:32 am, edited 4 times in total.

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J-J
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Re: Best way to quickly find a point?

Post by J-J » Wed Jul 28, 2021 6:05 am

why_is_this_not_closed-hatch.dxf
(616.65 KiB) Downloaded 28 times
broke polylines at intersections and got a closed contour
JJ Win7 pro-64

CVH
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Re: Best way to quickly find a point?

Post by CVH » Wed Jul 28, 2021 6:33 am

Hi, JJ
If I remove your hatch and try over with Hatch from Segments then I get:
Loop 1 not closed at point 1137.65/220.18.
Loop 2 not closed at point 1137.65/220.183.

Not even on the intended boundary ...

It works indeed with Hatch From Selection and trimmed entities like I mentioned.
Here I prefer to keep the horizontal line uncut and work with duplicates.

Regards,
CVH

turtle
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Re: Best way to quickly find a point?

Post by turtle » Wed Jul 28, 2021 5:52 pm

Thanks for the replies all, its a little over my head, but sounds like its a complex problem.
After 11 years I am still learning the basics LOL, however the time spent has had huge payoffs for my work.

I use Qcad to make 2D 'shop drawings' for electrical construction.
Sometimes I make a my own drawing from the start but often these days I get an architects plans exported from Revit or I export others plans from sketchup.

In other words I am not always in control of the lines and such as sometimes they expect to merge my changes back into the architects cad package.
This is an elevation view of a trench for underground utilities that I need to modify quite often, so your tips are greatly appreciated.
Thanks
--Turtle
Comments based on Version: 3.26.2 unless otherwise noted.

turtle
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Re: Best way to quickly find a point?

Post by turtle » Wed Jul 28, 2021 10:40 pm

Update so I removed more stuff to make a really simple test file.
And I moved the outline of the area I want to make the hatch in to a layer called 02-Hatch
Now I turn off all the other layers
select the outline and choose 'draw hatch from selection.
I now get Loop not closed at point '1137.62/219.148.' instead of a hatch
When drawing a line from two points I enter '1137.62, 219.148' as the starting point I can see thats the bottom right corner
And I am not sure how to check the coordinates of the two intersecting points but if a zoom really far in
they stay connected.
I am on Version:
3.26.2.0 (3.26.2)
Internet:
QCAD.org
Build Date:
Apr 13 2021
Revision:
57092ea
Qt Version:
5.8.0
Architecture:
x86_64
Compiler:
gcc 4.8.1
OS is Gentoo Linux
Attachments
why_is_this_not_closed-v3.dxf
(129.74 KiB) Downloaded 38 times
why_is_this_not_closed-v3.png
why_is_this_not_closed-v3.png (28.97 KiB) Viewed 1310 times
Comments based on Version: 3.26.2 unless otherwise noted.

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Husky
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Re: Best way to quickly find a point?

Post by Husky » Thu Jul 29, 2021 12:39 am

Hi turtle,

Note: Behind an "Automated Hatch" from selection is a very complex calculation what means QCAD needs a very clean contour to accomplish this task without any problems.

This said ... your example contour (why_is_this_not_closed-v3.dxf) isn't clean enough. The issue with that shape is that entity 2,3 and 4 is a duplicate. Additional an open contour at point 5 and an overshoot at point 6.

Husky-2021.07.28-01.png
Husky-2021.07.28-01.png (12.23 KiB) Viewed 1298 times

How did I find issue 5 and 6? If you get the message from the hatch tool that a Loop isn't closed it will also put a small circle at that point. Unfortunately - if you confirm the warning with OK and move the mouse pointer this circle will disappear.

Husky-2021.07.28-02.png
Husky-2021.07.28-02.png (14.38 KiB) Viewed 1298 times
Husky-2021.07.28-04.png
Husky-2021.07.28-04.png (13.75 KiB) Viewed 1298 times

Pay attention to those circles and check what could be wrong at that point!


If you fix those issues like me a hatch is easily created by QCAD:

cleaning hatch contour_.gif
cleaning hatch contour_.gif (1.91 MiB) Viewed 1298 times
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turtle
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Re: Best way to quickly find a point?

Post by turtle » Thu Jul 29, 2021 2:10 am

Husky 'your the man' as we used to say.
Thank you so much
Ill try this out.
This is a very large drawing for a commercial building so
is there some slick script or extension that can I can run files thru to
merge points that are in the same layer and within .0001 of each other or something?
cheers and stay cool
Comments based on Version: 3.26.2 unless otherwise noted.

CVH
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Re: Best way to quickly find a point?

Post by CVH » Thu Jul 29, 2021 6:15 am

Turtle,
Like husky examples, and my advise:
Only the (singular) surrounding entities ... Trimmed pair-wise.

One could exploit the fact that Polyline from Selection (OC) has a configurable tolerance and can bridge gaps.
Only, I would not advice that in general because of:
viewtopic.php?f=32&t=8412
Manual trimming ensures you keep most of the original unchanged.
For those polylines with bulge factors ensure that you pick the ending segments while trimming.
turtle wrote:
Thu Jul 29, 2021 2:10 am
is there some slick script or extension that can I can run files thru to
merge points that are in the same layer and within .0001 of each other or something?
cheers and stay cool
No, not really, because that changes some coordinates randomly without any control on what it should rely on.
Similar as what can be seen in the link above.

Regards,
CVH

CVH
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Re: Best way to quickly find a point?

Post by CVH » Thu Jul 29, 2021 7:07 am

What is most strange is that:
Loop not closed at point 1137.62/219.148.
Is in fact:
(1137.61922, 219.147544) & (1137.619220324963, 219.1475435043075)
And is matching within 5e-7, what should be close enough ... :?: :!:

Regards,
CVH

turtle
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Location: 43.9982926,-123.0633909

Re: Best way to quickly find a point?

Post by turtle » Thu Jul 29, 2021 5:29 pm

CVH wrote:
Thu Jul 29, 2021 7:07 am
What is most strange is that:
Loop not closed at point 1137.62/219.148.
Is in fact:
(1137.61922, 219.147544) & (1137.619220324963, 219.1475435043075)
And is matching within 5e-7, what should be close enough ... :?: :!:

Regards,
CVH
Thanks CVH, how do you see those numbers for a point?
Could be user error as I thought I moved all those points with snap set to auto, but it could have snapped to a part of a nearby hatch before I did the special layer.


--Turtle
Comments based on Version: 3.26.2 unless otherwise noted.

CVH
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Re: Best way to quickly find a point?

Post by CVH » Thu Jul 29, 2021 8:25 pm

turtle wrote:
Thu Jul 29, 2021 5:29 pm
Thanks CVH, how do you see those numbers for a point?
I have a custom script running that can document most entities in full floating point notation.

In a way one could do the same with a novel command line tool. (dwg2csv)
I only can't get that to run on a multi user Win7 32bit platform.
It works on a single user Win10 that is stand-alone for my CNC engraver.

One could read that directly from the dxf file, if one knows what to look for. :wink:
turtle wrote:
Thu Jul 29, 2021 5:29 pm
Could be user error as I thought I moved all those points with snap set to auto
The advice was to trim entities pair-wise.
Moving endpoints manually is not really the same with bulging polyline segments.
For how accurate things can be I have to refer to my PM .. Private Messages

regards,
CVH

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