SelectionSet

How do I create a selection set in VBA that has all MTEXT entities in the current layout (paperspace)?

Thanks,
MS

 

See pg. 267 of my 2000 book for an example.

Joe

 

No need for a selection set.

Public Sub MoveExample()
Dim basePoint(0 To 2) As Double
basePoint(0) = 0: basePoint(1) = 0: basePoint(2) = 0


Dim displacement(0 To 2) As Double
displacement(0) = 5.25: displacement(1) = -4.25: displacement(2) = 0

Dim ent As AcadEntity
For Each ent In ThisDrawing.ActiveLayout.Block
If TypeOf ent Is AcadMText Then
ent.Move basePoint, displacement
End If
Next ent
End Sub

 

This could be a very time consuming process. I think it be better to create
a selection set and iterate through just the selection set.

Joe
--

 

Hi Joe,
I've been involved in some rather lengthy, and at times somewhat heated,
discussions on this very topic right here in this newsgroup. If needed we
can rehash all of the details again, although it is the end of the week and
I really don't feel like it The thrust of my thoughts are:

a) "time consuming" is a relative term. If a selection set performs the
operation in X milliseconds and iteration via For Each performs it in 20X
milliseconds, will the end user see a difference? (Note that 20 is a random
factor that I pulled out of my...ummm...out of the air. Please see my
thoughts in section b as to what can affect this factor)

b) There are a plethora of variables involved that can affect the speed
difference in these two approaches. Deciding up front to only and always
use one is just not something that I'm willing to do. For example, it is
entirely possible given the original poster's provided situation that the
selection set method could actually take longer to run than iteration.
(Please see section a for my thoughts on speed difference)

c) All this typing is wearing me down, which is disconcerting considering
the actual lack of typing that I've done. My number one thought on this is
that I always code with readability, maintainability, and scalability in
mind before algorithm execution time. Sometimes this means that selection
sets are the way to go, but more often than not it means that iteration with
For Each is what I choose.

Have a good one!

 

Bobby,

What you stated is true until you start working with big (and I mean really
big) datasets. If your query additionaly relies on geometry (what is where),
you will need to implement selection sets and it's filters. For me, the most
time-consuming process is actually discovering how to override ACAD's
internal errors and inconsistencies related to spatial queries (i.e.
SelectByPolygon).

Regards,
Maksim Sestic

 

Nice plug, but sorry, I don't have your book.

I figured out one method:

For Each entity In ssetObj
If entity.OwnerID = ThisDrawing.PaperSpace.ObjectID Then
entity.Move point1, point2
End If
Next

In ARX there is a function acedXformSS() to transform asel-set by a transformation matrix, but I couldn't locate such a function in VBA... does it exist?

 

I think you're confusing what you perceive as 'internal errors and
inconsistencies', with your failure to understand graphical object
selection in AutoCAD.

It is only accurate to 1 screen pixel. It is not a true spatial
query in the analytical sense.

 

Tony,

I know you're right, but I'm still wondering if Autodesk is ever going to
solve this issue (graphical query vs. spatial query) on its basic platform.
There is no word on "accuracy issues" in ACAD's developer's guide. I'm
working with Map and it takes much more time to implement it's location
queries (in coding sense) than filtering out simple selection set based on
such query.

Regards,
Maksim Sestic