[mapguide-users] RE: Rendering Pass

Dave Wilson dave.wilson at autodesk.com
Fri Mar 26 15:41:05 EDT 2010


That is a good question. Depending on whether the labels are from points, lines or polygons plays a part in the performance as point labels have more things to consider than other labels if I understand the logic correctly. In your case it's polygon labels which are relatively simple. I would only convert the primary offending layer if you can get away with it. I would suspect symbols would require more processing, but by what factor I don't know, but considering the symbols are rendered before the labels, they don't have to consider all the placement issues that labels do so depending on the type of label it may be just as fast. The problem with converting all the layers might be issues with things rendering on top just like you do now unless you specify otherwise and I don't think the symbols have all the avoidance/placement logic labels do so things might get crowded looking where labels would be selectively drawn.

Maybe Walt will provide some insight here.

Dave

From: mapguide-users-bounces at lists.osgeo.org [mailto:mapguide-users-bounces at lists.osgeo.org] On Behalf Of Martin Morrison
Sent: Friday, March 26, 2010 1:26 PM
To: MapGuide Users Mail List
Subject: [mapguide-users] RE: Rendering Pass

Then that begs the question...which is faster labels as symbols or plain labels?  I would think that plain labels would be faster.  Or does it matter?  I would hate to convert my layers over to symbols to find the processing time has increased by 50%...

Martin



From: mapguide-users-bounces at lists.osgeo.org [mailto:mapguide-users-bounces at lists.osgeo.org] On Behalf Of Dave Wilson
Sent: Friday, March 26, 2010 3:20 PM
To: MapGuide Users Mail List
Subject: [mapguide-users] RE: Rendering Pass

Labels have a higher draw priority than symbols if I understand things correctly.

I think the simple solution is to render the label for the grid layer as a symbol as well and then your draw order will be preserved if the road layer is on top.

Dave

From: mapguide-users-bounces at lists.osgeo.org [mailto:mapguide-users-bounces at lists.osgeo.org] On Behalf Of Martin Morrison
Sent: Friday, March 26, 2010 1:06 PM
To: MapGuide Users Mail List
Subject: [mapguide-users] Rendering Pass

I have an issue with labels drawing on top of symbols.  In the attached JPG ( also at http://craig.gis.edsi.com/rendering_error.jpg), the road symbol (617) should be drawn on top of the map label (015).  I have my road layer set above the map border layer in Studio, verified it in Maestro via XML.

******XML snippet********
<MapLayer>
    <Name>Primary Roads</Name>
    <ResourceId>Library://Craig_CO/Layers/Primary_Roads.LayerDefinition</ResourceId>
    <Selectable>true</Selectable>
    <ShowInLegend>true</ShowInLegend>
    <LegendLabel>Primary Roads</LegendLabel>
    <ExpandInLegend>true</ExpandInLegend>
    <Visible>true</Visible>
    <Group>Transportation</Group>
  </MapLayer>

<extra layers deleted>

  <MapLayer>
    <Name>Map Borders</Name>
    <ResourceId>Library://Craig_CO/Layers/Map_Borders.LayerDefinition</ResourceId>
    <Selectable>true</Selectable>
    <ShowInLegend>true</ShowInLegend>
    <LegendLabel>Map Borders</LegendLabel>
    <ExpandInLegend>true</ExpandInLegend>
    <Visible>true</Visible>
    <Group>Boundaries</Group>
  </MapLayer>
***********************

I looked at RFC 29 via this link:

http://trac.osgeo.org/mapguide/wiki/MapGuideRfc29

The initial value was set to 2.

**********CODE snippet**********

                </SimpleSymbolDefinition>
                <RenderingPass>2</RenderingPass>
  </SimpleSymbol>
</CompoundSymbolDefinition>

*******************************

Setting this to 0 of course sends it behind the line drawn (expected behavior).  Setting it to a higher number (went as high as 20) seems to have no effect.

So is this a bug that rendering pass does not work correctly?  Or am I missing something?  If so, what is the proper usage in this situation?

Thanks
Martin Morrison
Application Engineer
Engineering Design Systems, Inc.
3780 Peters Creek Rd Ext SW
Roanoke, VA  24018
540-345-1410
gis.edsi.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/mapguide-users/attachments/20100326/8d7d80c1/attachment.html


More information about the mapguide-users mailing list