* In Vertex editing, restore the rubberbanding to moving verticies, w…

…hich was broken in r5550.

* Bonus bugfix: If two adjacent verticies were moved in succession, the second vertex would show a rubberband from the *old* position of the first vertex instead of the moved-to position of the first vertex.  This should now be fixed.

* Bonus function: New "get_at()" function in QgsGeometryVertexIndex.  Should be fairly self-explanitory.



git-svn-id: http://svn.osgeo.org/qgis/trunk@5568 c8812cc2-4d05-0410-92ff-de0c093fc19c

src/core/qgsgeometry.cpp

@@ -457,6 +457,243 @@ QgsPoint QgsGeometry::closestVertex(const QgsPoint& point, QgsGeometryVertexInde
 }
 
 
+void QgsGeometry::adjacentVerticies(const QgsGeometryVertexIndex& atVertex, int& beforeVertex, int& afterVertex) const
+{
+  if(mDirtyWkb)
+  {
+    exportGeosToWkb();
+  }
+
+  beforeVertex = -1;
+  afterVertex = -1;
+
+  if (mGeometry)
+  {
+    int vertexcounter = 0;
+
+    int wkbType;
+
+    memcpy(&wkbType, (mGeometry+1), sizeof(int));
+
+    switch (wkbType)
+    {
+      case QGis::WKBPoint:
+      {
+        // NOOP - Points do not have adjacent verticies
+        break;
+      }
+
+      case QGis::WKBLineString:
+      {
+        unsigned char* ptr = mGeometry+5;
+        int* npoints = (int*) ptr;
+
+        const int index = atVertex.back();
+
+        // assign the rubber band indices
+
+        if(index == 0)
+        {
+          beforeVertex = -1;
+        }
+        else
+        {
+          beforeVertex = index-1;
+        }
+
+        if(index == (*npoints - 1))
+        {
+          afterVertex = -1;
+        }
+        else
+        {
+          afterVertex = index+1;
+        }
+
+        break;
+      }
+      case QGis::WKBPolygon:
+      {
+        int* nrings=(int*)(mGeometry+5);
+        int* npoints;
+        unsigned char* ptr=mGeometry+9;
+
+        // Walk through the POLYGON WKB
+
+        for (int index0 = 0; index0 < *nrings; ++index0)
+        {
+          npoints=(int*)ptr;
+          ptr+=sizeof(int);
+
+          for (int index1 = 0; index1 < *npoints; ++index1)
+          {
+            ptr += sizeof(double);
+            ptr += sizeof(double);
+
+            if (vertexcounter == atVertex.back())
+            // TODO: The above is deprecated as it doesn't allow for multiple linear rings in the polygon.
+            // replace with the below when the rest of QgsGeometry is migrated to a GEOS back-end.
+            //if (
+            //    (index0 == atVertex.get_at(0)) &&
+            //    (index1 == atVertex.get_at(1))
+            //   )
+            {
+              // Found the vertex of the linear-ring we were looking for.
+
+              // assign the rubber band indices
+
+              if(index1 == 0)
+              {
+                beforeVertex = vertexcounter+(*npoints-2);
+                afterVertex = vertexcounter+1;
+              }
+              else if(index1 == (*npoints-1))
+              {
+                beforeVertex = vertexcounter-1;
+                afterVertex = vertexcounter - (*npoints-2);
+              }
+              else
+              {
+                beforeVertex = vertexcounter-1;
+                afterVertex = vertexcounter+1;
+              }
+            }
+
+            ++vertexcounter;
+          }
+        }
+        break;
+      }
+
+      case QGis::WKBMultiPoint:
+      {
+        // NOOP - Points do not have adjacent verticies
+        break;
+      }
+
+      case QGis::WKBMultiLineString:
+      {
+        unsigned char* ptr=mGeometry+5;
+        int* nlines=(int*)ptr;
+        int* npoints = 0;
+        ptr+=sizeof(int);
+
+        for (int index0 = 0; index0 < *nlines; ++index0)
+        {
+          ptr += (sizeof(int) + 1);
+          npoints = (int*)ptr;
+          ptr += sizeof(int);
+
+          for (int index1 = 0; index1 < *npoints; ++index1)
+          {
+            ptr+=sizeof(double);
+            ptr+=sizeof(double);
+
+            if (vertexcounter == atVertex.back())
+            // TODO: The above is deprecated as it doesn't allow for account for all ends of lines.
+            // replace with the below when the rest of QgsGeometry is migrated to a GEOS back-end.
+            //if (
+            //    (index0 == atVertex.get_at(0)) &&
+            //    (index1 == atVertex.get_at(1))
+            //   )
+            {
+              // Found the vertex of the linestring we were looking for.
+
+              // assign the rubber band indices
+
+              if(index1 == 0)
+                {
+                  beforeVertex = -1;
+                }
+              else
+                {
+                  beforeVertex = vertexcounter-1;
+                }
+              if(index1 == (*npoints)-1)
+                {
+                  afterVertex = -1;
+                }
+              else
+                {
+                  afterVertex = vertexcounter+1;
+                }
+              }
+            ++vertexcounter;
+          }
+        }
+
+        break;
+      }
+
+      case QGis::WKBMultiPolygon:
+      {
+        unsigned char* ptr=mGeometry+5;
+        int* npolys=(int*)ptr;
+        int* nrings;
+        int* npoints;
+        ptr+=sizeof(int);
+
+        for (int index0 = 0; index0 < *npolys; ++index0)
+        {
+          ptr += (1 + sizeof(int)); //skip endian and polygon type
+          nrings=(int*)ptr;
+          ptr+=sizeof(int);
+
+          for (int index1 = 0; index1 < *nrings; ++index1)
+          {
+            npoints=(int*)ptr;
+            ptr+=sizeof(int);
+
+            for (int index2 = 0; index2 < *npoints; ++index2)
+            {
+              ptr += sizeof(double);
+              ptr += sizeof(double);
+
+              if (vertexcounter == atVertex.back())
+              // TODO: The above is deprecated as it doesn't allow for multiple linear rings in the polygon.
+              // replace with the below when the rest of QgsGeometry is migrated to a GEOS back-end.
+              //if (
+              //    (index0 == atVertex.get_at(0)) &&
+              //    (index1 == atVertex.get_at(1)) &&
+              //    (index2 == atVertex.get_at(2))
+              //    )
+              {
+                // Found the vertex of the linear-ring of the polygon we were looking for.
+
+                // assign the rubber band indices
+
+                if(index2 == 0)
+                {
+                  beforeVertex = vertexcounter+(*npoints-2);
+                  afterVertex = vertexcounter+1;
+                }
+                else if(index2 == (*npoints-1))
+                {
+                  beforeVertex = vertexcounter-1;
+                  afterVertex = vertexcounter - (*npoints-2);
+                }
+                else
+                {
+                  beforeVertex = vertexcounter-1;
+                  afterVertex = vertexcounter+1;
+                }
+              }
+              ++vertexcounter;
+            }
+          }
+        }
+
+        break;
+      }
+
+      default:
+        break;
+    } // switch (wkbType)
+
+  } // if (mGeometry)
+}
+
+
 
 bool QgsGeometry::insertVertexBefore(double x, double y,
                                      int beforeVertex,

src/core/qgsgeometry.h

@@ -83,10 +83,27 @@ class QgsGeometry {
     void setGeos(geos::Geometry* geos);
 
     /**
-       Returns the vertex closest to the given point (and also vertex index, squared distance and indexes of the vertices before/after)
+       Returns the vertex closest to the given point 
+       (and also vertex index, squared distance and indexes of the vertices before/after)
     */
     QgsPoint closestVertex(const QgsPoint& point, QgsGeometryVertexIndex& atVertex, int& beforeVertex, int& afterVertex, double& sqrDist) const;
 
+
+    /**
+       Returns the indexes of the vertices before and after the given vertex index.
+
+       This function takes into account the following factors:
+
+       1. If the given vertex index is at the end of a linestring,
+          the adjacent index will be -1 (for "no adjacent vertex")
+       2. If the given vertex index is at the end of a linear ring
+          (such as in a polygon), the adjacent index will take into
+          account the first vertex is equal to the last vertex (and will
+          skip equal vertex positions).
+    */
+    void adjacentVerticies(const QgsGeometryVertexIndex& atVertex, int& beforeVertex, int& afterVertex) const;
+
+
     /** Insert a new vertex before the given vertex index,
      *  ring and item (first number is index 0)
      *  If the requested vertex number (beforeVertex.back()) is greater

src/core/qgsgeometryvertexindex.cpp

@@ -16,6 +16,8 @@ email                : morb at ozemail dot com dot au
 
 #include "qgsgeometryvertexindex.h"
 
+#include <iostream>
+
 
 QgsGeometryVertexIndex::QgsGeometryVertexIndex()
 {
@@ -47,17 +49,34 @@ void QgsGeometryVertexIndex::push_back(int& i)
   mIndex.push_back(i);
 }
 
-int QgsGeometryVertexIndex::back()
+int QgsGeometryVertexIndex::back() const
 {
 #ifdef QGISDEBUG
-  for(std::vector<int>::iterator it = mIndex.begin(); it != mIndex.end(); ++it)
-    {
-      qWarning("mIndex contains: "+QString::number(*it));
-    }
+  std::cout << "QgsGeometryVertexIndex::back: mIndex contains:";
+  for(std::vector<int>::const_iterator it = mIndex.begin(); it != mIndex.end(); ++it)
+  {
+    std::cout << " " << (*it);
+  }
+  std::cout << "." << std::endl;
 #endif
   return mIndex.back();
 }
 
+
+int QgsGeometryVertexIndex::get_at(int i) const
+{
+#ifdef QGISDEBUG
+  std::cout << "QgsGeometryVertexIndex::get_at: mIndex contains:";
+  for(std::vector<int>::const_iterator it = mIndex.begin(); it != mIndex.end(); ++it)
+  {
+    std::cout << " " << (*it);
+  }
+  std::cout << "." << std::endl;
+#endif
+  return mIndex[i];
+}
+
+
 void QgsGeometryVertexIndex::clear()
 {
   mIndex.clear();

src/core/qgsgeometryvertexindex.h

@@ -50,10 +50,15 @@ class QgsGeometryVertexIndex {
 
     /** Pushes an int onto the last (rightmost) element of the index */
     void push_back(int& i);
-    
+
     /** Gets the last (rightmost) element of the index */
-    int back();
-
+    int back() const;
+
+    /** Gets the i'th element of the index.
+        i=0 refers to the "innermost" line-string or linear-ring.
+     */
+    int get_at(int i) const;
+
     /** Resets the index */
     void clear();