Is there an easy way to create a new polygon layer?
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fgoldstein
Oct 15, 2008, 3:39:28 PM10/15/08
to MapInfo-L
This should be obvious but I don't see it anywhere. I'm looking for a
way to draw from scratch a new map layer, one not composed of polygons
from other layers but ones that I draw myself. Way back in the MI5.0
days, I did this once using instructions in the book for creating
cutting tools, one at a time for each polygon, to chip away at a
larger layer. That was tedious and error-prone. Surely there is some
kind of tool that lets me take a big area and draw lines to create
polygons that become map objects? Or is this some kind of special
developer's tool that they intentionally keep private, or very
expensive, in order to limit competition in the predrawn-layer market?
Just by way of example, let's say I wanted to create a map layer
showing school geocodes, and I had a city street map as a guide, but
geocodes did not line up with anything. Thanks.
way to draw from scratch a new map layer, one not composed of polygons
from other layers but ones that I draw myself. Way back in the MI5.0
days, I did this once using instructions in the book for creating
cutting tools, one at a time for each polygon, to chip away at a
larger layer. That was tedious and error-prone. Surely there is some
kind of tool that lets me take a big area and draw lines to create
polygons that become map objects? Or is this some kind of special
developer's tool that they intentionally keep private, or very
expensive, in order to limit competition in the predrawn-layer market?
Just by way of example, let's say I wanted to create a map layer
showing school geocodes, and I had a city street map as a guide, but
geocodes did not line up with anything. Thanks.
Mike Jamieson
Oct 15, 2008, 4:55:59 PM10/15/08
to mapi...@googlegroups.com
Would, "save cosmetic layer as" in the map menu work or are you looking
for something you can do programmatically?
Mike
for something you can do programmatically?
Mike
fgoldstein
Oct 15, 2008, 6:39:09 PM10/15/08
to MapInfo-L
On Oct 15, 4:55 pm, "Mike Jamieson" <mjamie...@taiga-ltd.com> wrote:
> Would, "save cosmetic layer as" in the map menu work or are you looking
> for something you can do programmatically?
layer as its basis.
For instance, if I'm mapping a city, cosmetic objects don't have the
underlying geographic
coordinates of the city that I'm drawing the layer atop of. I'd like
to relate the new layer to
a base map layer, just not based on existing components.
fgoldstein
Oct 16, 2008, 2:30:18 PM10/16/08
to MapInfo-L
I'm trying it more and remember the real issue... I can draw one
object,
using the cosmetic layer, but I don't see a way to make a line segment
in one object be the boundary of the next. So if I drew a line
between two
regions, I'd have to perfectly, exactly trace the same line for each
region.
How can one line be made to be the boundary between two polygons,
or more generally polygons be made by drawing the boundaries between
them, out of a bigger area?
object,
using the cosmetic layer, but I don't see a way to make a line segment
in one object be the boundary of the next. So if I drew a line
between two
regions, I'd have to perfectly, exactly trace the same line for each
region.
How can one line be made to be the boundary between two polygons,
or more generally polygons be made by drawing the boundaries between
them, out of a bigger area?
DougWassmer
Oct 16, 2008, 3:00:23 PM10/16/08
to mapi...@googlegroups.com
It is tedious, but you can highlight the nodes that you want to transfer and
then select them (select one end then shift-select the other end and all
should be selected unless there is a shorter route to the 2nd point). Then
copy-paste in the other layer. I used this to set up polygons in my area
with street and rivers as the boundary lines using the same nodes.
Doug Wassmer
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then select them (select one end then shift-select the other end and all
should be selected unless there is a shorter route to the 2nd point). Then
copy-paste in the other layer. I used this to set up polygons in my area
with street and rivers as the boundary lines using the same nodes.
Doug Wassmer
This message was checked by NOD32 antivirus system.
http://www.eset.com
David R Sherrod
Oct 16, 2008, 3:31:41 PM10/16/08
to mapi...@googlegroups.com
It sounds like you may be early on the learning curve. Forgive me if I've
misread your intent or if you're trying to achieve something far more
sophisticated than marked by the following instructions.
Two thoughts come to mind.
MapInfo has a "SNAP TO NODE" capability, which allows for the rapid tracing
of an existing line. Use your polyline drawing tool, and then hit the "s"
key on the keyboard. Depending on MI version number, the cursor may change
aspect instantly, but no matter. In all versions it will change aspect
whenever it is placed near an existing node. You can touch down there
(click the mouse button), then move some distance down the existing line to
an node and as you hover over it, press the shift key. You'll find your
line snaps to the existing line. Nodes for the new line are placed
automatically (and precisely) on the nodes of the existing line.
The other way to get coincident polygon boundaries is to draw your second
"intended polygon so that it overlaps with the polygon that you really
like. Select the polygon that you want to modify, then set it as the
target (OBJECTS-->Set Target). (Its patterning will change, to indicate
it's been selected.) Then pick the overlying desired polygon and
OBJECTS-->Erase. The overlying "cutter" will cut out the overlap and add
all the nodes needed.
Those are the two common methods for manual polygon creation, I think. You
might check the manual for those topics to learn more about some of the
options.
There are some catches that merit attention. Thus:
1. The cutter (the overlying polygon) has to be in a separate table.
That's not a big deal; you can always copy and paste it into a separate
table or into the cosmetic layer (as a temporary separate table, so to
speak).
2. As I understand it, precision is enhanced if the coordinate scheme and
projection is identical for the cutter's table and the object's table.
When constructing a map, I address this matter by creating a "CUTTER" table
(so named, because my memory is poor) that is in the same projection. Then
I paste my ideal or preferred polygon(s) into there so they can live in a
table that can be moved up or down in the pile as needed and will be in a
coincident projection scheme.
3. The newly created polygon may have more nodes (by two) than the
original linework if the cutter lacks a node where its line boundary
crosses over the underlying target. Does that make sense? Consequently,
you may find yourself periodically adding a node or two to an existing
polygon as you come to realize that you need coincidence among all the
polygons. Frankly, for GIS purposes, that probably is the best approach,
to have all your polygons share nodes, not just coincident boundaries.
If you play with this a bit, you'll work the kinks out of the shortness of
my explanation.
--------------------------------------------
David R. Sherrod, Cascades Volcano Observatory
U.S. Geological Survey,
1300 SE Cardinal Court, Bldg. 10
Vancouver, WA 98683
voice 360-993-8915
fax 360-993-8980
dshe...@usgs.gov
-----------------------------------------
fgoldstein
<ion...@gmail.com
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Please respond to Subject
mapinfo-l@googleg [MI-L] Re: Is there an easy way to
roups.com create a new polygon layer?
misread your intent or if you're trying to achieve something far more
sophisticated than marked by the following instructions.
Two thoughts come to mind.
MapInfo has a "SNAP TO NODE" capability, which allows for the rapid tracing
of an existing line. Use your polyline drawing tool, and then hit the "s"
key on the keyboard. Depending on MI version number, the cursor may change
aspect instantly, but no matter. In all versions it will change aspect
whenever it is placed near an existing node. You can touch down there
(click the mouse button), then move some distance down the existing line to
an node and as you hover over it, press the shift key. You'll find your
line snaps to the existing line. Nodes for the new line are placed
automatically (and precisely) on the nodes of the existing line.
The other way to get coincident polygon boundaries is to draw your second
"intended polygon so that it overlaps with the polygon that you really
like. Select the polygon that you want to modify, then set it as the
target (OBJECTS-->Set Target). (Its patterning will change, to indicate
it's been selected.) Then pick the overlying desired polygon and
OBJECTS-->Erase. The overlying "cutter" will cut out the overlap and add
all the nodes needed.
Those are the two common methods for manual polygon creation, I think. You
might check the manual for those topics to learn more about some of the
options.
There are some catches that merit attention. Thus:
1. The cutter (the overlying polygon) has to be in a separate table.
That's not a big deal; you can always copy and paste it into a separate
table or into the cosmetic layer (as a temporary separate table, so to
speak).
2. As I understand it, precision is enhanced if the coordinate scheme and
projection is identical for the cutter's table and the object's table.
When constructing a map, I address this matter by creating a "CUTTER" table
(so named, because my memory is poor) that is in the same projection. Then
I paste my ideal or preferred polygon(s) into there so they can live in a
table that can be moved up or down in the pile as needed and will be in a
coincident projection scheme.
3. The newly created polygon may have more nodes (by two) than the
original linework if the cutter lacks a node where its line boundary
crosses over the underlying target. Does that make sense? Consequently,
you may find yourself periodically adding a node or two to an existing
polygon as you come to realize that you need coincidence among all the
polygons. Frankly, for GIS purposes, that probably is the best approach,
to have all your polygons share nodes, not just coincident boundaries.
If you play with this a bit, you'll work the kinks out of the shortness of
my explanation.
--------------------------------------------
David R. Sherrod, Cascades Volcano Observatory
U.S. Geological Survey,
1300 SE Cardinal Court, Bldg. 10
Vancouver, WA 98683
voice 360-993-8915
fax 360-993-8980
dshe...@usgs.gov
-----------------------------------------
fgoldstein
<ion...@gmail.com
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Please respond to Subject
mapinfo-l@googleg [MI-L] Re: Is there an easy way to
roups.com create a new polygon layer?
Steve King
Oct 16, 2008, 6:59:49 PM10/16/08
to mapi...@googlegroups.com
If you have a significant number of polygons to create it or you plan to do
this in the future I would recommend buying third party software because
Mapinfos tools for this are not great. I use the polybuild module in
Discover which is excellent. You just need to draw a network of polylines
in a new table that will form the boundaries to your new polygons. You
don't even have to be too careful about snapping boundaries. Once you've
completed that, you use the tools to cut, extend and snap the polylines into
good topology and then build the polygons into a new table from the boundary
table - steps which only take a few minutes. I find it is best to retain
the layer of polylines that represent the boundaries so you can overlay this
on imagery if required - the associated polygon objects would then have a
fill pattern but no boundary style to form the map with the polyline layer.
this in the future I would recommend buying third party software because
Mapinfos tools for this are not great. I use the polybuild module in
Discover which is excellent. You just need to draw a network of polylines
in a new table that will form the boundaries to your new polygons. You
don't even have to be too careful about snapping boundaries. Once you've
completed that, you use the tools to cut, extend and snap the polylines into
good topology and then build the polygons into a new table from the boundary
table - steps which only take a few minutes. I find it is best to retain
the layer of polylines that represent the boundaries so you can overlay this
on imagery if required - the associated polygon objects would then have a
fill pattern but no boundary style to form the map with the polyline layer.
Steve
----- Original Message -----
From: "fgoldstein" <ion...@gmail.com>
To: "MapInfo-L" <mapi...@googlegroups.com>
Sent: Thursday, October 16, 2008 5:39 AM
Subject: [MI-L] Is there an easy way to create a new polygon layer?
>
fgoldstein
Oct 16, 2008, 10:40:02 PM10/16/08
to MapInfo-L
David, thank you for the advice. I didn't realize that the "S"
would make a new line snap to existing points, and that really
helps when I am using the drawing tools on the cosmetic layer.
The cutting-tool method is what I have used before. It's just so
tedious, though copying nodes would at least reduce some errors.
And it's quite unforgiving. A nice tool would let me move nodes
that separate polygons within the layer. Discover sounds like it
might be the kind of tool needed to do this... it has a free trial
though
the add-on module itself seems to cost more than MapInfo Pro
itself.
Thanks to all who have helped!
would make a new line snap to existing points, and that really
helps when I am using the drawing tools on the cosmetic layer.
The cutting-tool method is what I have used before. It's just so
tedious, though copying nodes would at least reduce some errors.
And it's quite unforgiving. A nice tool would let me move nodes
that separate polygons within the layer. Discover sounds like it
might be the kind of tool needed to do this... it has a free trial
though
the add-on module itself seems to cost more than MapInfo Pro
itself.
Thanks to all who have helped!
Lawley, Russell S
Oct 17, 2008, 3:50:23 AM10/17/08
to mapi...@googlegroups.com
One further way to build up a coverage of polygons is to take a look at
the 'Enclose' function in later versions of Mapinfo. I use this for
building polys all the time (it sounds a little like the discover tool
in its function). It is particularly useful if you already have a point
file that can be used as 'centroids' to populate the content of your
enclosed polygons...
Regards
R
-----Original Message-----
From: mapi...@googlegroups.com [mailto:mapi...@googlegroups.com] On
Behalf Of fgoldstein
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the 'Enclose' function in later versions of Mapinfo. I use this for
building polys all the time (it sounds a little like the discover tool
in its function). It is particularly useful if you already have a point
file that can be used as 'centroids' to populate the content of your
enclosed polygons...
Regards
R
-----Original Message-----
From: mapi...@googlegroups.com [mailto:mapi...@googlegroups.com] On
Behalf Of fgoldstein
Sent: 17 October 2008 03:40
To: MapInfo-L
To: MapInfo-L
This message (and any attachments) is for the recipient only. NERC is subject to the Freedom of Information Act 2000 and the contents of this email and any reply you make may be disclosed by NERC unless it is exempt from release under the Act. Any material supplied to NERC may be stored in an electronic records management system.
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David R Sherrod
Oct 17, 2008, 2:32:06 PM10/17/08
to mapi...@googlegroups.com
>A nice tool would let me move nodes that separate polygons within the
layer.
layer.
F.G.,
You may not have played with this option. Use the pulldown
OPTION-->Preferences-->Map Window-->Move Duplicate Nodes. That may answer
your goal to move nodes among polygons within a separate layer. You can
use the SNAP "s" feature to help you move nodes into coincident position
with other nodes, too.
By the way, while in there (Move D. N.), you can also see where the pixel
tolerance for the SNAP tool can be adjusted, among other things.
(Embedded image moved to file: pic26463.jpg)
--------------------------------------------
David R. Sherrod, Cascades Volcano Observatory
U.S. Geological Survey,
1300 SE Cardinal Court, Bldg. 10
Vancouver, WA 98683
voice 360-993-8915
fax 360-993-8980
dshe...@usgs.gov
-----------------------------------------
fgoldstein
<ion...@gmail.com
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Please respond to Subject
mapinfo-l@googleg [MI-L] Re: Is there an easy way to
roups.com create a new polygon layer?
Eric_Bl...@mapinfo.com
Oct 17, 2008, 2:33:45 PM10/17/08
to mapi...@googlegroups.com
I may have missed some part of this thread but the Objects Enclose command will take line/polyline objects and make regions out of all the enclosed areas.
Eric Blasenheim
Chief Product Architect
Pitney Bowes Business Insight [MapInfo]
Mail List:grbounce-yvy1equaaaajbprysysrydkk7vpghp_9=mail_list=mapin...@googlegroups.com
| From: | fgoldstein <ion...@gmail.com> on 10/16/2008 07:40 PM MST |
| To: | MapInfo-L <mapi...@googlegroups.com> |
| cc: | |
| Subject: | [MI-L] Re: Is there an easy way to create a new polygon layer? |
fgoldstein
Oct 17, 2008, 4:42:48 PM10/17/08
to MapInfo-L
Russell,
On Oct 17, 3:50 am, "Lawley, Russell S" <rs...@bgs.ac.uk> wrote:
> One further way to build up a coverage of polygons is to take a look at
> the 'Enclose' function in later versions of Mapinfo. I use this for
> building polys all the time (it sounds a little like the discover tool
> in its function). It is particularly useful if you already have a point
> file that can be used as 'centroids' to populate the content of your
> enclosed polygons...
That's an excellent suggestion! I was unaware of "enclose". I'm
using MIPro 8.5 but learned a lot of this in the 4.1-5.5 days, and
that
may be a new one I missed. It does create enclosed polygons.
The one problem is that while it lets me use "snap to" in order to
create
coincident lines, it is still two separate boundaries. So if I want
to move
a line, I'm moving both of them. And in a real district-type map,
almost
all of the boundaries will thus be two that way.
Thanks again; we're making progress!
On Oct 17, 3:50 am, "Lawley, Russell S" <rs...@bgs.ac.uk> wrote:
> One further way to build up a coverage of polygons is to take a look at
> the 'Enclose' function in later versions of Mapinfo. I use this for
> building polys all the time (it sounds a little like the discover tool
> in its function). It is particularly useful if you already have a point
> file that can be used as 'centroids' to populate the content of your
> enclosed polygons...
using MIPro 8.5 but learned a lot of this in the 4.1-5.5 days, and
that
may be a new one I missed. It does create enclosed polygons.
The one problem is that while it lets me use "snap to" in order to
create
coincident lines, it is still two separate boundaries. So if I want
to move
a line, I'm moving both of them. And in a real district-type map,
almost
all of the boundaries will thus be two that way.
Thanks again; we're making progress!
fgoldstein
Oct 17, 2008, 4:47:37 PM10/17/08
to MapInfo-L
David,
.,
hadn't
noticed that feature. Thanks for pointing it out. Yes, it is pretty
deep in the
preferences, so it is helpful that you told me where it was.
.,
> You may not have played with this option. Use the pulldown
> OPTION-->Preferences-->Map Window-->Move Duplicate Nodes. That may answer
> your goal to move nodes among polygons within a separate layer. You can
> use the SNAP "s" feature to help you move nodes into coincident position
> with other nodes, too.
>
> By the way, while in there (Move D. N.), you can also see where the pixel
> tolerance for the SNAP tool can be adjusted, among other things.
Sorry I missed that before writing my reply to the previous note -- I
> OPTION-->Preferences-->Map Window-->Move Duplicate Nodes. That may answer
> your goal to move nodes among polygons within a separate layer. You can
> use the SNAP "s" feature to help you move nodes into coincident position
> with other nodes, too.
>
> By the way, while in there (Move D. N.), you can also see where the pixel
> tolerance for the SNAP tool can be adjusted, among other things.
hadn't
noticed that feature. Thanks for pointing it out. Yes, it is pretty
deep in the
preferences, so it is helpful that you told me where it was.
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