The issue of the order that objects are created by MapInfo when importing from
MIF was amply resolved by Russell Mincher and Bob Young. The order that the
objects are created by MapInfo when importing from MIF is the same as the order
that is in the MIF. I already knew that, because I could see the same order
appearing in a browser, and the same order was kept if I performed another
export. I couldn't really think of a way to ask the question I wanted, but I
got the answer I needed anyway :-)
The order that objects are drawn in MapInfo is governed by the spatial index,
which is created when you import the MIF, and in fact is a part of every table
that has spatial records (records that can be drawn - that have a spatial
component). If you add or remove records from the table then the spatial index
is updated and you cannot be sure whether the objects will be drawn in the same
order as before.
There is no way to determine which record comes before which in the spatial
index as it is an internal house keeping function of MapInfo.
The only way you can be sure that an object will not appear above/below another
object is to have them in separate layers. Having the objects in separate
layers allows you to explicitly determine which object will be drawn over
which. Unfortunately the custom dgn converter we are using has only been
written to export the whole dgn file to one MIF and so this is not automatically
possible, perhaps if it was written to put different object types into separate
MIF files I could import them into MapInfo and then be able to order them. I
guess I wil start hassling the authors :-)
Thanks again guys,
Brad
Russell Mincher wrote:
> Thanks Bob,
>
> See Brad, I told you it was a dark and arcane sience
>
> Bob, just out of curiosity's sake, I take it from your agreement that layers
> are the way to go that is there is no easy way to identify and/or modify the
> spatial order to force MI to draw objects in the order desired?
>
> ----- Original Message -----
> From: Bob Young - www.bydesignwales.demon.co.uk
> <[EMAIL PROTECTED]>
> To: Russell Mincher <[EMAIL PROTECTED]>
> Cc: <[EMAIL PROTECTED]>; MapInfo mailing list <[EMAIL PROTECTED]>
> Sent: Thursday, May 11, 2000 11:07 PM
> Subject: Re: MI Order of creating objects from MIF
>
> > Dear Russ
> >
> >
> > I think your problem is not the order they are imported but the order
> > they are drawn.
> >
> > The order they are drawn is governed by the spatial index within
> > MapInfo. Therefore even if they did draw in the order you want today,
> > they may well not next week after further objects have been added to the
> > MAP file thus changing the spatial index. Objects are basically held in
> > rectangular blocks but there is a limit to the number per block. When
> > the block is full a new block is created and the existing items are
> > shared between the ( now ) two blocks leaving some " redundancy " for
> > new items. But the draw order is now different as all the objects in
> > block A will be drawn together then all the items in the other block
> > will be drawn together.
> >
> > You could have two items virtually adjacent but because the spatial
> > index divides between them the one object could be the first drawn in
> > the layer and the neighbouring one drawn last!
> >
> > If you want to get certain objects on top of others with MapInfo then
> > you need to use the layers. eg If you want text on top of rectangles put
> > all text objects in a seperate layer which is higher in your layer
> > control. There is no "bring to front" or "send to back" in a map window
> > ( only in the layout ).
> >
> > Hope this helps.
> >
> >
> > Regards
> >
> >
> > Bob
> > www.mapsbydesign.co.uk
> >
> >
> >
> >
> >
> > In message <00f301bfbabd$4afc57a0$0301a8c0@itec>, Russell Mincher
> > <[EMAIL PROTECTED]> writes
> > >The problem is not likely to be with the import, as far as I can tell MI
> > >creates the objects in the order they are read off the MIF. Your issue
> is
> > >likely to be the order MI draws them. This has been discussed on the
> list
> > >before and understanding the drawing order seems to require expertise in
> > >some dark and arcane science.
> > >
> > >I have found the only reliable way to put one thing on top of another is
> to
> > >have them in separate tables.
> > >
> > >Regards
> > >
> > >
> > >
> > >Russ
> > >
> > >----- Original Message -----
> > >From: Bradley Browne <[EMAIL PROTECTED]>
> > >To: MapInfo mailing list <[EMAIL PROTECTED]>
> > >Sent: Wednesday, May 10, 2000 7:06 PM
> > >Subject: MI Order of creating objects from MIF
> > >
> > >
> > >>
> > >> I am importing a table from mif into MapInfo Pro 5.5 and I am
> > >> noticing that I cannot seem to get it to import the objects in
> > >> the order I want it to. I have one mif export file with many
> > >> types of objects in it and I want to import it into MapInfo Pro.
> > >> The mif file has been created by a custom MicroStation dgn
> > >> converter that we have. When I import the mif, the order that
> > >> the objects are created is not the same as the order that they
> > >> appear in the mif file and so I am getting regions blocking out
> > >> point objects etc.
> > >>
> > >> Is there a rule that MapInfo Pro follows when it is importing
> > >> objects from mif format, so that I can understand how I can get
> > >> MapInfo Pro to create the objects in a desired order to get the
> > >> table looking the way I want it ?
> > >>
> > >> Cheers,
> > >>
> > >> Brad
> > >>
> > >> --
> > >> Bradley Browne
> > >> Support Manager
> > >> Desktop Mapping Systems Pty Ltd
> > >>
> > >> 1st Floor 646 Newcastle St
> > >> Leederville, WA 6007
> > >> Ph: +61 8 9328 2715 Fax: +61 8 9328 2716
> > >> email: [EMAIL PROTECTED]
> > >> http://www.mapsys.com.au/
> > >>
> > >>
> > >> ----------------------------------------------------------------------
> > >> To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
> > >> "unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
> > >>
> > >
> > >----------------------------------------------------------------------
> > >To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
> > >"unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
> >
> > --
> > Bob Young - www.bydesignwales.demon.co.uk
> >
>
> ----------------------------------------------------------------------
> To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
> "unsubscribe MAPINFO-L" in the message body, or contact [EMAIL PROTECTED]
--
Bradley Browne
Support Manager
Desktop Mapping Systems Pty Ltd
1st Floor 646 Newcastle St
Leederville, WA 6007
Ph: +61 8 9328 2715 Fax: +61 8 9328 2716
email: [EMAIL PROTECTED]
http://www.mapsys.com.au/
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To unsubscribe from this list, send e-mail to [EMAIL PROTECTED] and put
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