Topic: Hatch Area Question...

[alanjt]

I encountered a problem over at CADTutor and I was curious if any of the experts here might be able to shine some light on the situation.

Has anyone ever tried to get the area from a hatch object and been unsuccessful? I posted a very simple piece of code to tally the area of selected hatch objects. Problem is, the user cannot see the area of a selected hatch. If he LISTs the object, an area is not display and if he runs a (vlax-dump-object, the spot where ; Area - ### would be is missing. I get the area value (even from a posted drawing) and Lee was able to get the value.

Any thoughts?

[MP]

The area property will be null if an unbound entity / selection is hatched, e.g. an un-closed polyline.

[alanjt]

The area property will be null if an unbound entity / selection is hatched, e.g. an un-closed polyline.

The drawing just has closed LWPolylines. Most likely drawn with Rectangle.

[MP]

All 3 hatches in that drawing sport valid area property values, so I don't understand why it was posted.

[alanjt]

All 3 hatches in that drawing sport valid area property values, so I don't understand why it was posted.

I know. That's what makes this so confusing.
Link: http://www.cadtutor.net/forum/showthread.php?p=310953&posted=1#post310953

[MP]

I question whether the drawing posted here is the same in question over there.

[alanjt]

I question whether the drawing posted here is the same in question over there.

I asked that same thing before and asked again, just to make sure.

Response: Yes and I made an additional drawing with one hatch with a rectangle as well. The same problem exists in both drawings. I also tested this on two versions of acad as previously mentioned (2004 & 2009).

[MP]

The same problem exists in both drawings. I also tested this on two versions of acad as previously mentioned (2004 & 2009).

Wut. All three hatches show the area property via the list command, all three hatches show a valid area property via lisp.

PS: AutoCAD 2008, vanilla.

[alanjt]

The same problem exists in both drawings. I also tested this on two versions of acad as previously mentioned (2004 & 2009).

Wut. All three hatches show the area property via the list command, all three hatches show a valid area property via lisp.

PS: AutoCAD 2008, vanilla.

I know. I'm completely lost/confused. He tested it in vanilla 04 & 09, I tested it in C3D 09 and Lee tested it in vanilla 2010.

[Lee Mac]

I'm lost too... the only way I can actually get the Area to be null is to do as you say Michael, and hatch an open poly - but even in this case, the area property is still shown in the dump, just as an invalid value. In the CADTutor thread, the dump reveals no Area property whatsoever. I'm testing in ACAD 2010 Student and the posted DWG seems fine to me.

[MP]

Let me be clear: based on what was posted I see no problem.

It's either a student version anomaly (doubtful) or a PEBKAC error based on what I've seen thus far. Shrug.

[alanjt]

Let me be clear: based on what was posted I see no problem.

It's either a student version anomaly (doubtful) or a PEBKAC error based on what I've seen thus far. Shrug.

I hate not being able to find an answer, but without sitting at the computer, how can I? This is just so bizarre.

[hmspe]

I seem to remember having similar problems in the past.  One computer in the office would not report hatch areas but the other two would.  All computers had the same version of Autocad set up in the same way, and all were pulling the same file from a server.  As I recall two of the computers were identical except for video cards, and it was one of those two that would not report hatch area.  I checked system variables, settings, etc. and never found a solution.  I think we were running 2004 at the time. 

[CAB]

My understanding is that if the hatch is associative then there is an area else not.

[MP]

Sorry CAB, not true.

Code: [Select]

====================================Object====================================

<IAcadHatch 2124801128> (8/8 of <IAcadModelSpace2 2124774648>)

==================================Properties==================================

Application              <IAcadApplication>
[color=red]Area                     30.9975
AssociativeHatch         :vlax-false[/color]
Color                    256
Database                 <IAcadDatabase>
Document                 <IAcadDocument>
Elevation                0.0
EntityName               AcDbHatch
...