Changes between Initial Version and Version 1 of MapGuideRfc133

Timestamp:

04/17/13 09:08:51 (12 years ago)

Author:

jng

Comment:

--

MapGuideRfc133

@@ +1 @@
+
+= !MapGuide RFC 133 - Additional Stylization Expression Functions =
+
+This page contains a change request (RFC) for the !MapGuide Open Source project.
+More !MapGuide RFCs can be found on the [wiki:MapGuideRfcs RFCs] page.
+
+
+== Status ==
+
+||RFC Template Version||(1.0)||
+||Submission Date||18 Apr 2013||
+||Last Modified||18 Apr 2013||
+||Author||Jackie Ng||
+||RFC Status||draft||
+||Implementation Status||ready||
+||Proposed Milestone||2.6||
+||Assigned PSC guide(s)||(when determined)||
+||'''Voting History'''||(vote date)||
+||+1||||
+||+0||||
+||-0||||
+||-1||||
+||no vote|| ||
+
+== Overview ==
+
+This RFC proposes to add support for additional expression engine functions to allow for greater stylization flexibility
+
+== Motivation ==
+
+There are several scenarios that the current stylization expression function suite fails to address, mostly centered around tooltips:
+
+ * Ability to stylize based on current map scale (eg. Scale-dependent tooltips)
+ * Ability to stylize based on view location (eg. View-specific tooltips)
+ * Ability to construct useful tooltips for debugging/informative purposes due to key information that about the stylized feature that is missing
+
+This RFC expands the suite of FDO stylization functions to fulfil these scenarios
+
+== Proposed Solution ==
+
+Implement the following FDO expression engine functions in the Stylization library:
+
+ * HTMLCOLOR(r, g, b)+
+ * FEATURESOURCE()
+ * LAYERDEFINITION()
+ * MAPSCALE()
+ * MAPCENTERX()
+ * MAPCENTERY()
+
++ Denotes a MapGuide-specific stylization function
+
+Each function is described in detail below
+
+=== HTMLCOLOR(r, g, b) ===
+
+Returns the HTML color string based on the integer red, green and blue values provided. This function is more useful for tooltip construction where the existing ARGB() function is inadequate.
+
+=== FEATURESOURCE() ===
+
+Returns the resource ID of the Feature Source where this stylized feature originates from
+
+Implementation details:
+
+Store the Feature Source id into the RS_FeatureClassInfo class that is created and set before rendering begins and is also referred to by other stylization 
+
+functions. Evaluating this function returns this set value.
+
+=== LAYERDEFINITION() ===
+
+Returns the resource ID of the Layer Definition that is being used to stylize this feature
+
+Implementation details:
+
+Store the Layer Definition id into the RS_LayerUIInfo class that is created and set before rendering begins and is also referred to by other stylization 
+
+functions. Evaluating this function returns this set value.
+
+=== MAPSCALE() ===
+
+Returns the current scale of the map being rendered.
+
+Implementation details:
+
+We store the map scale into the RS_MapUIInfo class that is created and set before rendering begins and is also referred to by other stylization functions. 
+
+Evaluating this function returns this set value.
+
+=== MAPCENTERX() ===
+
+Returns the X coordinate of the map's current view center
+
+Implementation details:
+
+We store the X coordinate into the RS_MapUIInfo class that is created and set before rendering begins and is also referred to by other stylization functions. 
+
+Evaluating this function returns this set value.
+
+=== MAPCENTERY() ===
+
+Returns the Y coordinate of the map's current view center
+
+Implementation details:
+
+We store the Y coordinate into the RS_MapUIInfo class that is created and set before rendering begins and is also referred to by other stylization functions. 
+
+Evaluating this function returns this set value.
+
+== Implications ==
+
+Layer definitions that use expressions containing theming functions will be stylized correctly only on MapGuide servers from a release that implements those functions.
+
+== Test Plan ==
+
+Render some labels exercising all of the above functions for a layer in a map at various positions and zoom levels. The labels rendered out should contain the expected values returned by these functions.
+
+== Funding / Resources ==
+
+Community