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One of the problems I think we have is road widths. Mapnik
currently renders all highways of the same type the same width - it
ignores lanes and width:<br>
<br>
<a class="moz-txt-link-freetext" href="http://wiki.openstreetmap.org/wiki/Lanes">http://wiki.openstreetmap.org/wiki/Lanes</a> (2,117,599 usage with
highway)<br>
<a class="moz-txt-link-freetext" href="http://wiki.openstreetmap.org/wiki/Key:width">http://wiki.openstreetmap.org/wiki/Key:width</a> (560,000 usage with
highway)<br>
<br>
If you check the style sheet:<br>
<br>
<a class="moz-txt-link-freetext" href="http://trac.openstreetmap.org/browser/applications/rendering/mapnik/osm.xml">http://trac.openstreetmap.org/browser/applications/rendering/mapnik/osm.xml</a><br>
<br>
(look for bits like this:)<br>
<Rule><br>
<Filter>[highway] = 'trunk' and not [tunnel] =
'yes'</Filter><br>
&maxscale_zoom17;<br>
&minscale_zoom18;<br>
<LineSymbolizer><br>
<CssParameter
name="stroke">#a9dba9</CssParameter><br>
<CssParameter
name="stroke-width">15.5</CssParameter><br>
<CssParameter
name="stroke-linejoin">round</CssParameter><br>
<CssParameter
name="stroke-linecap">round</CssParameter><br>
</LineSymbolizer><br>
</Rule><br>
<br>
No references to lanes.<br>
<br>
(If you care, using this handy table:
<a class="moz-txt-link-freetext" href="http://wiki.openstreetmap.org/wiki/FAQ#What_is_the_map_scale_for_a_particular_zoom_level_of_the_map.3F">http://wiki.openstreetmap.org/wiki/FAQ#What_is_the_map_scale_for_a_particular_zoom_level_of_the_map.3F</a>
, you can compute that at zoom level 17 at 45 degrees latitude, we
will always draw a highway=trunk 15.5 pixels * <span
class="Apple-style-span" style="color: rgb(0, 0, 0); font-family:
sans-serif; font-size: 12px; font-style: normal; font-variant:
normal; font-weight: normal; letter-spacing: normal; line-height:
19px; orphans: 2; text-align: -webkit-auto; text-indent: 0px;
text-transform: none; white-space: normal; widows: 2;
word-spacing: 0px; -webkit-text-size-adjust: auto;
-webkit-text-stroke-width: 0px; background-color: rgb(249, 249,
249); display: inline !important; float: none; "></span>1.689 =
26.2 meters wide - at 3 meters a lanes, that is roughly 8 lanes
wide.).<br>
<br>
I once tried rendering with highways fixed widths and then
overridden using Lanes or width if the data was present. The
results are "interesting". There are roughly 45 million highway =
* ways. That means roughly 1 in 20 (optimistically) have a lanes
tag. Image a way for bridge has a lanes tag but the ways connecting
to it doesn't. You wind up with a fat bridge connected to skinny
highways - not as nice looking as the map we currently present.<br>
<br>
I believe our rendering of highway widths solution is currently in a
local maxima - it looks pretty now, but to move forward we may need
to make it look less pretty until the underlying data gets even
better. (This is similar to the innovators dilemma). To make this
change to our primary renderer will require courage.<br>
<br>
John<br>
<br>
<br>
On 64-07-22 11:59 AM, Arun Ganesh wrote:
<blockquote
cite="mid:%3CCA+GKQr31qvv+8cBJGTaOM9NtiZhhk+3ynqsCCcddNT-=6chRdw@mail.gmail.com%3E"
type="cite">
<div>I am totally blown away by the level of detail provided by
the map providers in Korea. Even the navigation devices they use
in almost any vehicle is of a much higher level than anything I
have seen outside. As the car approaches a flyover or a
junction, the device actually renders a 3d view of the area from
the pov of the vehicle, with detailed buildings, trees and
lighting to match the time of the day. Each lane of the road is
marked with turn restrictions and speed limits.<br>
</div>
<div><br>
</div>
<div>All the gloating we do of the capabilities of osm fades in
comparison to what's been achieved here. We are years away from
reaching such a level where it will possible to crowdsource data
to such a detailed level in a consistent manner.</div>
<br>
<div class="gmail_quote">On Thu, Nov 3, 2011 at 9:00 PM, <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:talk-request@openstreetmap.org">talk-request@openstreetmap.org</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex;">
<br>
<br>
<a moz-do-not-send="true"
href="http://local.daum.net/map/index.jsp?t__nil_navi=bestmain&nil_id=map"
target="_blank">http://local.daum.net/map/index.jsp?t__nil_navi=bestmain&nil_id=map</a><br>
<br>
<a moz-do-not-send="true" href="http://map.naver.com/"
target="_blank">http://map.naver.com/</a><br>
<br>
</blockquote>
</div>
</blockquote>
<br>
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