There is no better summary then Eric's information.

We tried to avoid to double the amount of files we use and to change
over 150 wor's. I could not convince my colleague yesterday but by now
He is adopting all his little programs...

Thanks again to all who responded.
Christine

-----Urspr�ngliche Nachricht-----
Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] 
Gesendet: Dienstag, 31. August 2004 19:38
An: Christine Schildhauer
Cc: [EMAIL PROTECTED]
Betreff: Re: MI-L drawing order for lines


Christine and all of MapInfo -L,

Let me dispel some incorrect information that is being listed.

   There is no way to permanently control the draw order of objects
within
   a layer.  Layers are the only unit of draw order. Objects are drawn
in
   the order they come back from the spatial index and that is
determined
   by the density of objects in an area, the size of the internal blocks
   and the implementation of the data source (MapInfo native files,
MapInfo
   data stored in a database such as MapInfo SpatialWare or third party
   vendors such as Oracle where we have absolutely no say over the
order).
   The order is definitely NOT the order in which the data is created
and
   is not in any way related to the Rowids of the records. What makes
some
   people think this is true is the fact that when you insert or edit
data
   in MapInfo Professional, the edits are stored in a temporary separate
   file with its own indexes. MapInfo manages the issues so that only
the
   latest edited version of the object is displayed. This fact results
in a
   display order where objects that have not yet been saved are
displayed
   on top. However, as soon as those changes are committed, that order
is
   permanently lost. So, I suppose you could cut and paste data that you
   wanted on top, quickly print or save images of the map and then get
the
   result you wanted. However, that is only temporary.
   Exporting and reimporting via MIF has essentially the same impact as
a
   pack which can, in ways that are hard to determine, change the draw
   order.

The best way to do this is definitely to separate the objects into
separate tables or to use query tables to dynamically query the correct
objects and put those result set tables into the correct layer order.
The speed will be best as separate tables but depending on how much data
you have, using
queries may be and often is quite acceptable.   I am interested in why
this
is not a viable option.

As to why we do not have this feature, I would start a different thread
on that. The short answer is that we could but it is unclear how one
would decide what was drawn when. If the criteria was based on data, the
implementation would best do queries just as you can now. If the
criteria was arbitrary, then you have some draw order list, which is
only manageable for small amounts of data and will be slow because the
draw code can't use the spatial index.

Like I said, if you want to continue this discussion, I would start a
new thread.

Eric Blasenheim
Software Architect
MapInfo Corporation



Mail List:
 
[EMAIL PROTECTED]
 

 From:      on 08/31/2004 03:56 PM ZE2

 

 To:       <[EMAIL PROTECTED]>

 

 cc:

 

 Subject:  MI-L drawing order for lines

 




Hi list,
is it possible to force Mapinfo to draw lines in a userdefined order
within one layer ? I have one layer with lots of lines. The lines have a
gray or yellow color. I would like to draw all grey lines first and the
yellow ones on top of the grey.

I know it would be possible to select the grey and the yellow ones in
different queries or separat layers, and manage the order in the table
manager - but we don't want to do it this way.

Trying to sort the table with the grey lines as first datasets and the
yellow lines as last datasets doesn't help. So far I thought Mapinfo
draws objects in the order of the datasets but wrong...

Any suggestions?

Mit freundlichen Gr��en
Christine Schildhauer

Ingenieurgruppe IVV GmbH
Saarbr�cker Stra�e 36A
10405 Berlin
Tel: (030) 818 772-13
Fax: (030) 818 772-22
MailTo:[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
http:\\www.ivv-berlin.de <http://www.ivv-berlin.de/>



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