calculate the area of a surface?

[dumfatnhappy]

I've searched and can't find the answer I need. I need to find the area of these 2 outside surfaces. Anyone have a solution?

 

thanks,

[SEANT]

The wall thickness is small enough that a good approximation could be had by retrieving the area via-

 

Command: _area

Specify first corner point or [Object/Add/Subtract]: Object

 

and dividing by 2.

 

 

 

 

Or, if you are feeling adventurous, use the routine attaced by

 

Command: Netload

Command: SFA

 

Note: It is best to select edges of solids while in 2D Wireframe visual style.

SolidFaceArea_a.zip

[dumfatnhappy]

I appreciate that Seant but no joy. I got this error when invoking SFA.

 

any other thoughts?

 

****************************************************

 

See the end of this message for details on invoking

just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************

System.MissingMethodException: Method not found: 'Int32 Autodesk.AutoCAD.EditorInput.SelectedObject.get_GraphicsSystemMarker()'.

at SolidTools.SelectionProcessor.ProcessNow()

at SolidTools.STSCCommands.SolidFaceArea()

at Autodesk.AutoCAD.Runtime.CommandClass.InvokeWorker(MethodInfo mi, Object commandObject, Boolean bLispFunction)

at Autodesk.AutoCAD.Runtime.CommandClass.InvokeWorkerWithExceptionFilter(MethodInfo mi, Object commandObject, Boolean bLispFunction)

at Autodesk.AutoCAD.Runtime.CommandClass.CommandThunk.Invoke()

 

************** Loaded Assemblies **************

mscorlib

Assembly Version: 2.0.0.0

Win32 Version: 2.0.50727.3074 (QFE.050727-3000)

CodeBase: http://file:///C:/Windows/Microsoft.NET/Framework64/v2.0.50727/mscorlib.dll

----------------------------------------

acdbmgd

[SEANT]

Can I assume from this line that you are using a 64bit environment.

 

file:///C:/Windows/Microsoft.NET/[color="Red"]Framework64[/color]/v2.0.50727/mscorlib.dll

 

Unfortunately, I have no 64 bit machine on which to test code.

 

That Area/2 method is not sounding so bad.

[dumfatnhappy]

area can't see a 'surface'... and on the solid I think it is giving me more of a volume as that cylinder is 8' in dia. and it says the bigger one has a "surface" of 231 inches which really doesn't compute..

[SEANT]

The area command, with Object suboption, should give the total surface area of a selected solid. With the thin wall thickness, half of the returned area should be fairly close to the area of one of its faces.

 

Is it possible to post the DWG file?

[dumfatnhappy]

here it is. one pair is (still) a solid and the other is a 'surface'

 

see what you can do with it. cuz I'm at a loss....

screen area.dwg

[SEANT]

This is what I get from the area command. Each of those figures should be divided by 2. Those figures seem pretty reasonable.

 

Command: _area
Specify first corner point or [Object/Add/Subtract]: o

Select objects:

Area = 35614.31 square in. (247.3216 square ft.), Perimeter = 0'-0"

Command:
AREA
Specify first corner point or [Object/Add/Subtract]: o

Select objects:

Area = 19811.81 square in. (137.5820 square ft.), Perimeter = 0'-0"

[Guest]

You can always figure it out the old school way. (see the attached image.) It is not automatic, but it will get the job done. I have seen some stuff that will 'unfold' meshes, maybe that will help.

[SEANT]

By the way, here is what the SFA routine would return when it is running properly.

[dumfatnhappy]

By the way, here is what the SFA routine would return when it is running properly.

 

 

THAT IS AWESOME seant! Thank you very much.

 

let me know when you get the 64 bit code?

 

[SEANT]

dum,

 

If you would be so kind. . . . could you test this version. I set the Visual Studio compiler to target a 64bit processor. It compiled okay, but gave a warning about the referenced AutoCAD assemblie's 32bit status.

 

I imagine I will need a 64bit setup to have access to the appropriate 64bit Acad assemblies, but I’d like to make sure before I consider dumping big bucks on a system.

SolidFaceArea_64.zip