Changes between Version 25 and Version 26 of FDORfc48

Timestamp:

Aug 8, 2010, 8:17:54 PM (14 years ago)

Author:

leaf

Comment:

--

FDORfc48

@@ -183 +183 @@
 Autodesk to provide resources / funding.
 
+== Addendum, Aug. 9, 2010 ==
+
+This RFC provides some utility methods to check polygon vertex order and fix polygon vertex order errors. However, what action should be taken when copying a polygon from one feature source to another feature source isn't addressed in this RFC. The following enum and method will be introduced to address it. 
+
+{{{
+/// \brief
+/// FdoFixPolygonVertexOrderAction is an enumeration of the action taken 
+/// when copying polygon from a source provider to a target provider.
+///
+enum FdoPolygonVertexOrderAction
+{
+    /// No processing.
+    FdoFixPolygonVertexOrderAction_None = 0,
+
+    /// Reverse polygon vertex.
+    FdoFixPolygonVertexOrderAction_Reverse = 1,
+
+    /// Check polygon vertex order and reverse it if necessary.
+    FdoFixPolygonVertexOrderAction_CheckAndReverse = 2
+};
+
+
+/// \brief
+/// Spatial utility class
+///
+class FdoSpatialUtility
+{
+public:
+    /// \brief
+    /// Given the vertex order and strictness rule of the source and the target,
+    /// get the action taken when copying polygon from a source provider to 
+    /// a target provider.
+    ///
+    /// \param sourceVertexOrderRule
+    /// Input the vertex order rule of the source.
+    /// \param sourceStrictnessRule
+    /// Input the vertex order strictness rule of the source.
+    /// \param targetVertexOrderRule
+    /// Input the vertex order rule of the target.
+    /// \param targetStrictnessRule
+    /// Input the vertex order strictness rule of the target.
+    /// 
+    /// \return
+    /// Returns the action taken to taken when copying polygon from a source
+   /// provider to a target provider.
+    /// 
+    FDO_SPATIAL_API static FdoPolygonVertexOrderAction GetFixPolygonVertexOrderAction(
+        FdoPolygonVertexOrderRule sourceVertexOrderRule,
+        FdoBoolean sourceStrictnessRule,
+        FdoPolygonVertexOrderRule targetVertexOrderRule,
+        FdoBoolean targetStrictnessRule);
+};
+}}}
+
+Method !GetPolygonVertexOrderAction is used to get what action should be taken when copying a polygon from one feature source to another feature source. The following table is defined in this method. 
+
+{{{
+static FdoFixPolygonVertexOrderAction table1[36] = {
+                                                    // From Order    From Strict    To Order    To Strict     NonSense
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CCW           Enforced       CCW         Enforced
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Enforced       CCW         Not enforced
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CCW           Enforced       CW          Enforced
+    FdoFixPolygonVertexOrderAction_Reverse,         // CCW           Enforced       CW          Not enforced
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Enforced       None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Enforced       None        Not enforced
+
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CCW           Not enforced   CCW         Enforce
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Not enforced   CCW         Not enforced
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CCW           Not enforced   CW          Enforced
+    FdoFixPolygonVertexOrderAction_Reverse,         // CCW           Not enforced   CW          Not enforced
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Not enforced   None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // CCW           Not enforced   None        Not enforced
+
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CW            Enforced       CCW         Enforced
+    FdoFixPolygonVertexOrderAction_Reverse,         // CW            Enforced       CCW         Not enforced
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CW            Enforced       CW          Enforced
+    FdoFixPolygonVertexOrderAction_None,            // CW            Enforced       CW          Not enforced
+    FdoFixPolygonVertexOrderAction_None,            // CW            Enforced       None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // CW            Enforced       None        Not enforced
+
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CW            Not enforced   CCW         Enforced
+    FdoFixPolygonVertexOrderAction_Reverse,         // CW            Not enforced   CCW         Not enforced
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // CW            Not enforced   CW          Enforced
+    FdoFixPolygonVertexOrderAction_None,            // CW            Not enforced   CW          Not enforced
+    FdoFixPolygonVertexOrderAction_None,            // CW            Not enforced   None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // CW            Not enforced   None        Not enforced
+
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // None          Enforced       CCW         Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // None          Enforced       CCW         Not enforced  True
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // None          Enforced       CW          Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // None          Enforced       CW          Not enforced  True
+    FdoFixPolygonVertexOrderAction_None,            // None          Enforced       None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None,            // None          Enforced       None        Not enforced  True
+
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // None          Not enforced   CCW         Enforced
+    FdoFixPolygonVertexOrderAction_None,            // None          Not enforced   CCW         Not enforced
+    FdoFixPolygonVertexOrderAction_CheckAndFix,     // None          Not enforced   CW          Enforced
+    FdoFixPolygonVertexOrderAction_None,            // None          Not enforced   CW          Not enforced
+    FdoFixPolygonVertexOrderAction_None,            // None          Not enforced   None        Enforced      True
+    FdoFixPolygonVertexOrderAction_None             // None          Not enforced   None        Not enforced
+};
+
+}}}
+
+Actions defined in the table above will guarantee that polygons in the target will have the correct vertex order if the target is enforced when copying a polygon from one feature source to another feature source.