editing: show during mouse move where the point will be snapped to (b…

…y the expense of some performance)

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@5417 c8812cc2-4d05-0410-92ff-de0c093fc19c

src/core/qgsgeometry.cpp

@@ -313,30 +313,31 @@ QgsPoint QgsGeometry::closestVertex(const QgsPoint& point, QgsGeometryVertexInde
 	    {
 		unsigned char* ptr=mGeometry+5;
 		int* nlines=(int*)ptr;
-		int* npoints;
+		int* npoints = 0;
 		ptr+=sizeof(int);
 		for(int index=0;index<*nlines;++index)
 		{
-		    npoints=(int*)ptr;
-		    ptr+=sizeof(int);
-		    for(int index2=0;index2<*npoints;++index2)
+		  ptr += (sizeof(int) + 1);
+		  npoints=(int*)ptr;
+		  ptr+=sizeof(int);
+		  for(int index2=0;index2<*npoints;++index2)
 		    {
-			tempx=(double*)ptr;
-			ptr+=sizeof(double);
-			tempy=(double*)ptr;
-			if(point.sqrDist(*tempx,*tempy)<actdist)
+		      tempx=(double*)ptr;
+		      ptr+=sizeof(double);
+		      tempy=(double*)ptr;
+		      ptr+=sizeof(double);
+		      if(point.sqrDist(*tempx,*tempy)<actdist)
 			{
-			    x=*tempx;
-			    y=*tempy;
-			    actdist=point.sqrDist(*tempx,*tempy);
-			    vertexnr = vertexcounter;
+			  x=*tempx;
+			  y=*tempy;
+			  actdist=point.sqrDist(*tempx,*tempy);
+			  vertexnr = vertexcounter;
 			}
-			ptr+=sizeof(double);
-			++vertexcounter;
+		      ++vertexcounter;
 		    }
 		}
 	    }
-		break;
+	    break;
 
 	    case QGis::WKBMultiPolygon:
 	    {
@@ -482,6 +483,7 @@ bool QgsGeometry::moveVertexAt(double x, double y, QgsGeometryVertexIndex atVert
 	int pointindex = 0;
 	for(int linenr = 0; linenr < *nrLines; ++linenr)
 	  {
+	    ptr += sizeof(int) + 1;
 	    nrPoints = (int*)ptr;
 	    ptr += sizeof(int);
 	    if(vertexnr >= pointindex && vertexnr < pointindex + (*nrPoints))
@@ -840,7 +842,6 @@ bool QgsGeometry::insertVertexBefore(double x, double y, QgsGeometryVertexIndex
     {
     case QGis::WKBPoint://cannot insert a vertex before another one on point types
     case QGis::WKBMultiPoint:
-      break;
     case QGis::WKBLineString:
       {
 	int* nPoints = (int*)ptr;
@@ -871,6 +872,9 @@ bool QgsGeometry::insertVertexBefore(double x, double y, QgsGeometryVertexIndex
 	break;
       }
     case QGis::WKBMultiLineString:
+      {
+	break;
+      }
     case QGis::WKBPolygon:
       {
 	int* nRings = (int*)ptr;
@@ -1092,6 +1096,7 @@ bool QgsGeometry::vertexAt(double &x, double &y,
 		ptr += sizeof(int);
 		for(int linenr = 0; linenr < *nLines; ++linenr)
 		  {
+		    ptr += sizeof(int) + 1;
 		    nPoints = (int*)ptr;
 		    ptr += sizeof(int);
 		    for(int pointnr = 0; pointnr < *nPoints; ++pointnr)
@@ -1271,6 +1276,7 @@ QgsPoint QgsGeometry::closestSegmentWithContext(QgsPoint& point,
 	int pointindex = 0;//global pointindex
 	for(int linenr = 0; linenr < *nLines; ++linenr)
 	  {
+	    ptr += sizeof(int) + 1;
 	    nPoints = (int*)ptr;
 	    ptr += sizeof(int);
 	    prevx = 0;

src/gui/qgsmaptoolcapture.cpp

@@ -108,11 +108,10 @@ void QgsMapToolCapture::canvasReleaseEvent(QMouseEvent * e)
     if(vlayer->getDataProvider()->capabilities()&QgsVectorDataProvider::AddFeatures)
     {
       QgsFeature* f = new QgsFeature(0,"WKBPoint");
-
+      QgsPoint savePoint = maybeInversePoint(idPoint, "adding point");
       // snap point to points within the vector layer snapping tolerance
-      vlayer->snapPoint(idPoint, tolerance);
       // project to layer's SRS
-      QgsPoint savePoint = maybeInversePoint(idPoint, "adding point");
+      vlayer->snapPoint(savePoint, tolerance);
 
       // create geos geometry and attach it to feature      
       int size=5+2*sizeof(double);
@@ -162,7 +161,6 @@ void QgsMapToolCapture::canvasReleaseEvent(QMouseEvent * e)
     QgsPoint digitisedPoint = toMapCoords(e->pos());
     vlayer->snapPoint(digitisedPoint, tolerance);
     mCaptureList.push_back(digitisedPoint);
-
     mRubberBand->addPoint(digitisedPoint);
 
     if (e->button() == Qt::LeftButton)
@@ -272,7 +270,11 @@ void QgsMapToolCapture::canvasMoveEvent(QMouseEvent * e)
   if (mCapturing)
   {
     // show the rubber-band from the last click
-    mRubberBand->movePoint(toMapCoords(e->pos()));
+    QgsVectorLayer *vlayer = dynamic_cast <QgsVectorLayer*>(mCanvas->currentLayer());
+    double tolerance  = QgsProject::instance()->readDoubleEntry("Digitizing","/Tolerance",0);
+    QgsPoint rbpoint = toMapCoords(e->pos());
+    vlayer->snapPoint(rbpoint, tolerance); //show snapping during dragging
+    mRubberBand->movePoint(rbpoint);
   }
 
 } // mouseMoveEvent

src/gui/qgsmaptoolvertexedit.cpp

@@ -47,13 +47,19 @@ void QgsMapToolVertexEdit::canvasMoveEvent(QMouseEvent * e)
 {
   if (e->buttons() == Qt::LeftButton && (mTool == AddVertex || mTool == MoveVertex))
   {
-
-#ifdef QGISDEBUG
-        qWarning("Moving rubber band for moveVertex");
-#endif
-
       int index = (mStartPointValid ? 1 : 0);
-      mRubberBand->movePoint(index, toMapCoords(e->pos()));
+      //snap to nearest vertex of vectorlayer
+      QgsPoint rbpoint = toMapCoords(e->pos());
+      if(mTool == AddVertex)
+	{
+	  snapVertex(rbpoint, mSnappedAtFeatureId, mSnappedBeforeVertex.back());
+	  mRubberBand->movePoint(index, rbpoint);
+	}
+      else if(mTool == MoveVertex)
+	{
+	  snapVertex(rbpoint, mSnappedAtFeatureId, mSnappedAtVertex.back());
+	  mRubberBand->movePoint(index, rbpoint);
+	}
   }
 
 }
@@ -304,6 +310,7 @@ void QgsMapToolVertexEdit::canvasReleaseEvent(QMouseEvent * e)
 
     //snap to nearest vertex of vectorlayer
     snapVertex(point, mSnappedAtFeatureId, mSnappedBeforeVertex.back());
+
 #ifdef QGISDEBUG
     std::cout << "QgsMapToolVertexEdit::canvasReleaseEvent: AddVertex." << std::endl;
 #endif
@@ -360,3 +367,28 @@ void QgsMapToolVertexEdit::deactivate()
   mRubberBand = 0;
 }
 
+QgsPoint QgsMapToolVertexEdit::maybeInversePoint(QgsPoint point, const char whenmsg[])
+{
+  QgsVectorLayer *vlayer = dynamic_cast <QgsVectorLayer*>(mCanvas->currentLayer());
+  QgsPoint transformedPoint;
+
+  if( mCanvas->projectionsEnabled() )
+  {
+    // Do reverse transformation before saving. If possible!
+    try
+    {
+      transformedPoint = vlayer->coordinateTransform()->transform(point, QgsCoordinateTransform::INVERSE);
+    }
+    catch(QgsCsException &cse)
+    {
+      //#ifdef QGISDEBUG
+      std::cout << "Caught transform error when " << whenmsg <<"." 
+          << "Setting untransformed values." << std::endl;
+      //#endif  
+      // Transformation failed,. Bail out with original rectangle.
+      return point;
+    }
+    return transformedPoint;
+  }
+  return point;
+}

src/gui/qgsmaptoolvertexedit.h

@@ -57,6 +57,11 @@ class QgsMapToolVertexEdit : public QgsMapTool
 
     //! returns tolerance in map coordinates
     double tolerance();
+
+    /** Helper function to inverse project a point if projections
+        are enabled. Failsafe, returns the sent point if anything fails.
+        @whenmsg is a part fo the error message. */
+    QgsPoint maybeInversePoint(QgsPoint point, const char whenmsg[]);
 
     //! current vertex edit tool
     enum Tool mTool;