<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
<title></title>
</head>
<body bgcolor="#ffffff" text="#000000">
Steve Lime schrieb:
<blockquote cite="mids44cdb0b.044@co5.dnr.state.mn.us" type="cite">
<pre wrap="">Could you post an image or two showing the output you are looking for?
Steve
</pre>
<blockquote type="cite">
<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">"Peter Freimuth (MapMedia GmbH)" <a class="moz-txt-link-rfc2396E" href="mailto:pf@MAPMEDIA.DE"><pf@MAPMEDIA.DE></a> 4/24/2006 4:24:48 AM >>>
</pre>
</blockquote>
</blockquote>
</blockquote>
<pre wrap=""><!---->Dear mapserver-dev Team,
in context of using mapserver to generate a digital nautical mapchart
out of s57 data (imported into postgres/postgis), we found two missing
features to solve this task. Both features can be useful in a lot of
other areas.
- new feature type ARC, defined by:
STARTANGLE in Degree (west=0/360, north = 90 ,east=180,south=270)
ENDANGLE in degrees or ARCANGLE (negative value means clockwise
direction) in degrees
RADIUS (meter, miles or whatever)
The feature can be used in the same manner as every other line or
polygon feature. GD supports drawing of arcs so it should be not a big
problem to introduce the parameters in the mapfileparser and to handle
this featuretype inside of the current drawing routines.
- draw a symbol at the center of polygons or lines (it is possible for
labels so why not using the label offset point for symbol placement in
the same way); it is possible to solve this inside of PostGIS, but i
think it would also be a nice function for other datasources.
Thanks for your interest and any feedback to this!
Kind regards
Peter
</pre>
</blockquote>
<br>
<pre wrap="">Dear Steve and Mapserver-Dev Team,</pre>
<br>
<pre wrap="">This image shows the main problem we have at the moment. The arcs with different
colors that are drawn between the lines coming from the same circle center used
to define the arc itself. There is also one area with a symbol (red triangles)
on line signature which would be possible if we activate the code which we
allready send to steve which enables us to draw symbols inside or outside of
polygon boundaries.
- I understand the points mentioned by Frank in regard to WKT, shapeObj and
reprojecting. If we want to handle these objects like standard geo objects, we
have to convert them into simple feature objects inside of postgis or with the
help of the converter (franks fantastic ogr s57 reader/writer lib in this case)
On the other hand we are speaking about a "MAP" Server, which main task is to
produce good looking maps for the web. So if you look at the arc feature from
the mapping aspect there should be a possibility to support such features. In
this context of nautical maps charts, the projection is always the same and will
not change. Even if we have to reproject this object (because somebody makes the
software to do this), we only have the reprojected arc center (center of the
circle, where the arc is just a clipped part), the unchanged distance and the
angles (both params cannot be handled by projection libs). Its the same for the
lines that limits the arc on the left and right. They are defined by an angle
and the length if I understood it correctly. So the problem is inside of the
data definition and makes it impossible for any software to handle this in an
other way as mapserver might do
- I will have a look at the bug mentioned by Steve W. The main problem is, that
I do not have a clear Idea of how to implement it (especially how the user
interface should look like). I thought about a symbol section inside of the
Label objekt (which breaks the object structure) or to use introduce a
signalword inside of the symbol object which is used by the drawing function to
identify the meaning of this symbol (pattern, line style or symbol at center. If
somebody cann support me to find a logical and clear solution for an interface I
would be pleased to implement a first patch for testing.
Kind regards,
Peter</pre>
<pre class="moz-signature" cols="72">--
Mit freundlichem Gruß
Peter Freimuth
_________________________________________________
MapMedia GmbH
Kartographie und raumbezogene Informationssysteme
Heilbronner Straße 10
D-10711 Berlin Charlottenburg
fon: +49.(0)30.89 06 82 70
fax: +49.(0)30.89 06 82 73
mail: <a class="moz-txt-link-abbreviated" href="mailto:pf@mapmedia.de">pf@mapmedia.de</a>
net: <a class="moz-txt-link-abbreviated" href="http://www.mapmedia.de">www.mapmedia.de</a>
pgp: on demand
_________________________________________________</pre>
</body>
</html>