Polyline Area Problem

[mpkeane]

I am working on a Mac PowerBook, using OS 10.4.11, with VW Designer (Educational Version) 12.5.3

I have a plan drawing of a park. The scale is correct when I measure objects in the drawing. Areas of groundcover have been symbolized with polyline shapes infilled with patterns. When I look at the Object Info palette for those polyline shapes, however, to get a sense of the area of the groundcover, the perimeter and area shown are way, way too small.

If the scale of the drawing is correct, why is the area of the polyline incorrect?

Marc

[Benson Shaw]

Marc - My OS and VW are same as yours. And, I am using an old PowerBook, too!

If you mean that you are using a polyline as a representation of a planting area, but did not create a VW symbol from the poly, then you probably did not close the poly, even if it looks closed. To get an area readout, it needs to be closed. Check your poly's start and end points with the OIP and use Show next edge button to close.

If you mean that you have a poly which you converted to a VW symbol, then the above may apply, plus the following: I created an unclosed poly (end points close but not touching), duplicated it and used "Show next edge" to close the dupe. Then I duplicated the closed poly twice and created a symbol from each dupe. Symbol 1 has no options selected during creation. Symbol 2 is created with "Convert to Group/PIO" option selected.

The unclosed poly shows no area value in the OIP.

The closed polyline shows an area in the OIP.

Symbol 1 inserts as a symbol and shows no area in the OIP.

Symbol 2 inserts as a poly and shows correct area in the OIP.

Perhaps your area readout is showing only closed polylines and polygons, but none of your symbols or unclosed polys. I duped one instance of Symbol 1 (no area) and used the "Replace" button in the OIP to change it to Symbol 2. Strangely, the OIP identifies this new object as a symbol named Symbol 2 - but no area readout. Go figure.

I did not test it, but I think you can attach a record to the poly within the symbol and get the area to readout in a worksheet.

Seems like class designation might be a better way to go on this than symbol. You could make global selections, attribute edits, etc.

-B

[mpkeane]

Thank you for your help Benson.

Your answer made me think, so I tried an experiment. I drew a box with the rectangle tool that was 10 x 15 feet. The OIP shows 10 x 15 feet. I then traced that box with the polyline tool, closed the polyline and infilled the result with a pattern. The result should, naturally, have a perimeter of 50 linear feet and an area of 150 square feet. The OIP, however, shows 4 vertices (which is correct) but a perimeter of 50 INCHES!, and an area of 1.042 square feet!!

In fact, looking back at the OIP for the original rectangle I drew with the rectangle tool, it too shows a perimeter of 50 INCHES, and an area of 1.042 square feet.

The OIP, the tape measure tool, and the line measuring tool, show that the rectangle and polyline are 10 x 15 feet, but the perimeter and area readings are wrong.

Any idea what is going wrong here? Or what I am doing wrong?

Marc

[mpkeane]

Benson;

Just one more thing, I opened a blank document, and tried the same experiment. All the readings are correct. So the problem is not VW in general, but this one file somehow.

Any idea how to correct this corrupt file?

Marc

[Benson Shaw]

Dunno for sure. Try another test: Paste one of your bad objects into a new doc and see what it does.

Are you working on this in a design layer? Annotation mode of a viewport? Or are you by chance tracing over objects in a viewport set to 1:12 scale? That would give the feet to inch change. Note: You can change layer scale in the Nav pallet, the layer pulldown, and in the document prefs. They should update each other, but make sure the sale shows the same in those places.

Do a backup and try some of these:

Easy:

1. Reboot the computer and do system maintenance - permissions, logs, caches

2. Open document prefs and change the units setting, say to miles or yards, check the OIP, then reset the units back to your preferred setting.

3. Close VW, duplicate the file, open the copy. If it's OK, delete the orig.

4. Delete/redraw the bad objects in the orig file.

More Difficult:

1. Open a new VW file and copy/paste the objects, a few at at time, from orig doc.

2. Trash the VW plist file, which means you will need to redo all your prefs when you reopen VW. This can be very tedious unless you are working with defaults.

Harsh:

1. Start over on a new file and draw all new objects.

Maybe others can suggest a good way to uncorrupt a drawing file.

-B

[mpkeane]

Benson;

Your comment about changing the units clued me in to my (incredibly stupid) mistake. I had the file set in "inches" as a unit. What I thought was 10 by 15 feet, in fact was 10 x 15 inches.

I need to rework the whole drawing. It is 1/12th of what I thought it should be. I can Scale the whole thing up but then the plants are way too small.

Thank you.

Marc

[Benson Shaw]

Can you edit copies of the plant symbols to scale them up, then use Replace?

-B