Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
I have found that some multipolygons use nested inner polygons. Example: * A forest (outer) with a lake (inner) that has an island (inner) which is not a forest. (example: http://www.openstreetmap.org/browse/relation/331402) By definition of the multipolygon relation (http://wiki.openstreetmap.org/wiki/Relation:multipolygon) one has to create two mps. But I see that it is a nice simplification lots of mappers are using. Attached patch handles this situation. The inner and outer roles are now used as follows: * the outmost polygon must have role=outer (or role=empty) * all outmost polygons with role=inner are not used (a warning is issued) * all inside polygons with role=inner use their own tagging * all inside polygons with role=outer use the mp tagging if available or their own tagging if the mp is not tagged * all inside polygons with role=empty are categorized automatically as outer/inner depending on the nest level * all inside polygons with role=outer without a direct ambient inner polygon are dropped with a warning message (outer in outer polygon) Most of the renderers do not support inner in inner polygons but I think it is a very reasonable extension of the multipolygon handling. This patch also improves the error messages. I haven't seen any more are not processed due to an unknown reason messages and I look forward that the community will also not be able to generate any more ... ;-) WanMil There have been different opinions about this patch. There is one controversal point: Should mkgmap allow nested inner polygons? From my point of view: YES. Because it does not harm in any way. The nested inner polygons I analysed were all reasonable. Ok, they are not 100% compliant to the specification but this is common to lots of others things in (anarchic) OSM. At the moment I see two possible changes: 1. Issue a warning for any nested inner polygon but process it anyhow. 2. Reject nested inner polygons (and issue a warning). What a pity but they are not 100% compliant. Please let me know what's the opinion of mkgmap community and committers because I want the improvements of error messages to be committed. WanMil ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
Jeffrey Ollie schrieb am 02.03.2010 21:07: I've listened to that argument for a while and I'm tired of it. And I have tried to fight this anarchy and I got tired of it. So I accepted it as a fact and became much more relaxed and satisfied with OSM :-) Gruss Torsten ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
WanMil schrieb: I have found that some multipolygons use nested inner polygons. Example: * A forest (outer) with a lake (inner) that has an island (inner) which is not a forest. (example: http://www.openstreetmap.org/browse/relation/331402) But neither mapnik nor osmarender show the inner-inner island (wood), because this construct is not a valid advanced-multipolygon. Chris The patch supports the complete multipolygon specification. And additionally it is tolerant towards incorrect (but reasonable) multipolygons. So why should mkgmap be restrictive if it doesn't need to? WanMil ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
WanMil schrieb am 02.03.2010 18:48: The patch supports the complete multipolygon specification. And additionally it is tolerant towards incorrect (but reasonable) multipolygons. So why should mkgmap be restrictive if it doesn't need to? Since there is not really a specification for the OSM tagging, mkgmap should not check the data for correctness but try to support as much taggings as possible. So for example in a style file you must also check for typical typing errors, e.g. centre vs center. Gruss Torsten ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
On Tue, Mar 2, 2010 at 1:12 PM, Torsten Leistikow de_m...@gmx.de wrote: WanMil schrieb am 02.03.2010 18:48: The patch supports the complete multipolygon specification. And additionally it is tolerant towards incorrect (but reasonable) multipolygons. So why should mkgmap be restrictive if it doesn't need to? Since there is not really a specification for the OSM tagging, mkgmap should not check the data for correctness but try to support as much taggings as possible. So for example in a style file you must also check for typical typing errors, e.g. centre vs center. I've listened to that argument for a while and I'm tired of it. Complete anarchy when tagging make writing software to use OSM data incredibly difficult. At some point people are going to have to grow up and come to an agreement on tagging standards and then stick to it. -- Jeff Ollie ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
On Tue, Mar 2, 2010 at 1:12 PM, Torsten Leistikowde_m...@gmx.de wrote: WanMil schrieb am 02.03.2010 18:48: The patch supports the complete multipolygon specification. And additionally it is tolerant towards incorrect (but reasonable) multipolygons. So why should mkgmap be restrictive if it doesn't need to? Since there is not really a specification for the OSM tagging, mkgmap should not check the data for correctness but try to support as much taggings as possible. So for example in a style file you must also check for typical typing errors, e.g. centre vs center. I've listened to that argument for a while and I'm tired of it. Complete anarchy when tagging make writing software to use OSM data incredibly difficult. At some point people are going to have to grow up and come to an agreement on tagging standards and then stick to it. Ok, so revert the description of the patch: * The patch detects polygons with role=outer that is inside another polygon with role=outer and issues a warning for that. The inner in inner case is a well known error :-) WanMil ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
[mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
I have found that some multipolygons use nested inner polygons.
Example:
* A forest (outer) with a lake (inner) that has an island (inner) which
is not a forest. (example:
http://www.openstreetmap.org/browse/relation/331402)
By definition of the multipolygon relation
(http://wiki.openstreetmap.org/wiki/Relation:multipolygon) one has to
create two mps. But I see that it is a nice simplification lots of
mappers are using.
Attached patch handles this situation.
The inner and outer roles are now used as follows:
* the outmost polygon must have role=outer (or role=empty)
* all outmost polygons with role=inner are not used (a warning is issued)
* all inside polygons with role=inner use their own tagging
* all inside polygons with role=outer use the mp tagging if available or
their own tagging if the mp is not tagged
* all inside polygons with role=empty are categorized automatically as
outer/inner depending on the nest level
* all inside polygons with role=outer without a direct ambient inner
polygon are dropped with a warning message (outer in outer polygon)
Most of the renderers do not support inner in inner polygons but I think
it is a very reasonable extension of the multipolygon handling.
This patch also improves the error messages. I haven't seen any more
are not processed due to an unknown reason messages and I look forward
that the community will also not be able to generate any more ... ;-)
WanMil
Index: src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonRelation.java
===
--- src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonRelation.java
(revision 1593)
+++ src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonRelation.java
(working copy)
@@ -1,6 +1,7 @@
package uk.me.parabola.mkgmap.reader.osm;
-import java.awt.*;
+import java.awt.Polygon;
+import java.awt.Rectangle;
import java.awt.geom.Area;
import java.awt.geom.Line2D;
import java.awt.geom.PathIterator;
@@ -479,14 +480,19 @@
}
private ArrayListPolygonStatus getPolygonStatus(BitSet
outmostPolygons,
- boolean outer) {
+ String defaultRole) {
ArrayListPolygonStatus polygonStatusList = new
ArrayListPolygonStatus();
for (int polyIndex = outmostPolygons.nextSetBit(0); polyIndex
= 0; polyIndex = outmostPolygons
.nextSetBit(polyIndex + 1)) {
// polyIndex is the polygon that is not contained by
any other
// polygon
JoinedWay polygon = polygons.get(polyIndex);
- polygonStatusList.add(new PolygonStatus(outer,
polyIndex, polygon));
+ String role = getRole(polygon);
+ // if the role is not explicitly set use the default
role
+ if (role == null || .equals(role)) {
+ role = defaultRole;
+ }
+ polygonStatusList.add(new
PolygonStatus(outer.equals(role), polyIndex, polygon));
}
return polygonStatusList;
}
@@ -511,16 +517,17 @@
}
}
+ // join all single ways to polygons, try to close ways and
remove non closed ways
polygons = joinWays(allWays);
closeWays(polygons);
removeUnclosedWays(polygons);
- // now we have closed ways == polygons only
+ // now only closed ways are left = polygons only
// check if we have at least one polygon left
if (polygons.isEmpty()) {
// do nothing
- log.warn(Multipolygon + toBrowseURL()
+ log.info(Multipolygon + toBrowseURL()
+ does not contain a closed
polygon.);
cleanup();
return;
@@ -538,21 +545,29 @@
// the intersectingPolygons marks all intersecting/overlapping
polygons
intersectingPolygons = new HashSetJoinedWay();
+
+ // check which polygons lie inside which other polygon
createContainsMatrix(polygons);
+ // unfinishedPolygons marks which polygons are not yet processed
BitSet unfinishedPolygons = new BitSet(polygons.size());
unfinishedPolygons.set(0, polygons.size());
// create bitsets which polygons belong to the outer and to the
inner role
BitSet innerPolygons = new BitSet();
+ BitSet taggedInnerPolygons = new BitSet();
BitSet outerPolygons = new BitSet();
+ BitSet taggedOuterPolygons = new BitSet();
+
int wi = 0;
for (Way w : polygons) {
Re: [mkgmap-dev] [PATCH v1] Multipolygon: Allow nested inner polygons
WanMil schrieb: I have found that some multipolygons use nested inner polygons. Example: * A forest (outer) with a lake (inner) that has an island (inner) which is not a forest. (example: http://www.openstreetmap.org/browse/relation/331402) But neither mapnik nor osmarender show the inner-inner island (wood), because this construct is not a valid advanced-multipolygon. Chris ___ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
