Changes between Version 3 and Version 4 of FDORfc63

Timestamp:

05/17/12 13:26:03 (13 years ago)

Author:

danstoica

Comment:

--

FDORfc63

@@ -23 +23 @@
 == Overview ==
 
-This RFC is for ....
+This RFC is for adding a in-memory Spatial Index to FDO Spatial project. 
 
 == Motivation ==
@@ -219 +219 @@
 }}}
 
+== Remarks ==
+
+The API proposes 3 modes. This provides maximum flexibility for various scenarios.
+For mode #2 and #3 the client code has to implement a segment visitor in order to retrieve a segment from the geomtry. 
+
+The actual implementation will be the R-tree implementation found under Sqlite provider and developed by Traian Stanev. 
+
 == How to use this API ==
 
-The following code illustrates how to 
+The following code illustrates how to use the Spatial Index and the spatial index iterator.
+
+
+{{{
+    FdoPtr<FdoSpatialIndex> si;
+
+    FdoPtr<FdoFgfGeometryFactory> gf = FdoFgfGeometryFactory::GetInstance();
+  
+    /*************************** Test Polygon *************************/
+    FdoStringP geomText = L"POLYGON ((0 0, 5 0, 5 5, 0 5, 0 0), (1 1, 2 2, 2 1, 1 1), (3 3, 4 4, 4 3, 3 3))";
+ 
+    FdoPtr<FdoIGeometry> geom = gf->CreateGeometry(geomText);
+    FdoPtr<FdoByteArray> ba = gf->GetFgf(geom);
+
+    // Mode #1: FdoSpatialIndex_ByGeometriesBoundingBox
+    si = FdoSpatialIndex::Create(FdoSpatialIndex_ByGeometriesBoundingBox);
+
+    // Insert the geometry
+    si->InsertObject(777, ba);
+
+    // Query the SI
+    FdoSpatialIndexIterator iter1(si, 1, 1, 2, 2);
+
+    FdoInt32 iPart, iSubpart, iSegment;
+    FdoInt64 marker = 0;
+
+    // Get the results
+    while (marker = iter1.GetNextObject())
+    {
+        FdoInt64 fid = marker; // not encoded
+        // ... do stuff         
+    }
+        
+    // Mode #2: FdoSpatialIndex_BySegmentsMultipleFeatures
+    si = FdoSpatialIndex::Create(FdoSpatialIndex_BySegmentsMultipleFeatures);
+    si->InsertObject(777, ba);
+
+    FdoSpatialIndexIterator iter2(si, 1, 1, 2, 2);
+
+    while (marker = iter2.GetNextObject())
+    {
+        FdoInt32 fid;
+        si->DecodeMarker(marker, fid, iSegment);
+        // ... do stuff
+    }
+        
+    // Mode #3: FdoSpatialIndex_BySegmentsSingleFeature
+    si = FdoSpatialIndex::Create(FdoSpatialIndex_BySegmentsSingleFeature);
+    si->InsertObject(0, ba); // FeatId = 0
+
+    FdoSpatialIndexIterator iter3(si, 1, 1, 2, 2);
+
+    while (marker = iter3.GetNextObject())
+    {
+        si->DecodeMarker(marker, iPart, iSubpart, iSegment);
+        // ... do stuff
+    }
+}}}
 
 == Managed FDO API ==