Merge pull request #2290 from mhugent/geometry_marker

Geometry marker

Author: mhugent

python/core/geometry/qgsabstractgeometryv2.sip

@@ -116,4 +116,8 @@ class QgsAbstractGeometryV2
     virtual bool hasCurvedSegments() const;
     /** Returns a geometry without curves. Caller takes ownership*/
     virtual QgsAbstractGeometryV2* segmentize() const /Factory/;
+
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @return rotation in radians, clockwise from north*/
+    virtual double vertexAngle( const QgsVertexId& vertex ) const = 0;
 };

python/core/geometry/qgscircularstringv2.sip

@@ -55,6 +55,11 @@ class QgsCircularStringV2: public QgsCurveV2
 
     bool hasCurvedSegments() const;
 
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    double vertexAngle( const QgsVertexId& vertex ) const;
+
   private:
     void segmentize( const QgsPointV2& p1, const QgsPointV2& p2, const QgsPointV2& p3, QList<QgsPointV2>& points ) const;
 };

python/core/geometry/qgscompoundcurvev2.sip

@@ -60,4 +60,9 @@ class QgsCompoundCurveV2: public QgsCurveV2
     void sumUpArea( double& sum ) const;
 
     bool hasCurvedSegments() const;
+
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    double vertexAngle( const QgsVertexId& vertex ) const;
 };

python/core/geometry/qgscurvepolygonv2.sip

@@ -62,4 +62,9 @@ class QgsCurvePolygonV2: public QgsSurfaceV2
 
     bool hasCurvedSegments() const;
     QgsAbstractGeometryV2* segmentize() const /Factory/;
+
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    double vertexAngle( const QgsVertexId& vertex ) const;
 };

python/core/geometry/qgsgeometrycollectionv2.sip

@@ -51,4 +51,9 @@ class QgsGeometryCollectionV2: public QgsAbstractGeometryV2
     virtual double area() const;
 
     bool hasCurvedSegments() const;
+
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    double vertexAngle( const QgsVertexId& vertex ) const;
 };

python/core/geometry/qgslinestringv2.sip

@@ -55,4 +55,9 @@ class QgsLineStringV2: public QgsCurveV2
     bool pointAt( int i, QgsPointV2& vertex, QgsVertexId::VertexType& type ) const;
 
     void sumUpArea( double& sum ) const;
+
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    double vertexAngle( const QgsVertexId& vertex ) const;
 };

python/core/geometry/qgspointv2.sip

@@ -55,4 +55,9 @@ class QgsPointV2: public QgsAbstractGeometryV2
 
       double closestSegment( const QgsPointV2& pt, QgsPointV2& segmentPt,  QgsVertexId& vertexAfter, bool* leftOf, double epsilon ) const;
       bool nextVertex( QgsVertexId& id, QgsPointV2& vertex ) const;
+
+      /** Angle undefined. Always returns 0.0
+          @param vertex the vertex id
+          @return 0.0*/
+      double vertexAngle( const QgsVertexId& vertex ) const;
 };

python/core/qgsrendercontext.sip

@@ -85,4 +85,11 @@ class QgsRenderContext
     //! Added in QGIS v2.4
     const QgsVectorSimplifyMethod& vectorSimplifyMethod() const;
     void setVectorSimplifyMethod( const QgsVectorSimplifyMethod& simplifyMethod );
+
+    /** Returns pointer to the unsegmentized geometry
+        @return the geometry*/
+    const QgsAbstractGeometryV2* geometry() const;
+    /** Sets pointer to original (unsegmentized) geometry
+        @geometry the geometry*/
+    void setGeometry( const QgsAbstractGeometryV2* geometry );
 };

src/core/geometry/qgsabstractgeometryv2.h

@@ -317,6 +317,11 @@ class CORE_EXPORT QgsAbstractGeometryV2
      */
     virtual QgsAbstractGeometryV2* segmentize() const { return clone(); }
 
+    /** Returns approximate rotation angle for a vertex. Usually average angle between adjacent segments.
+        @param vertex the vertex id
+        @return rotation in radians, clockwise from north*/
+    virtual double vertexAngle( const QgsVertexId& vertex ) const = 0;
+
   protected:
     QgsWKBTypes::Type mWkbType;
     mutable QgsRectangle mBoundingBox;

src/core/geometry/qgscircularstringv2.cpp

@@ -953,3 +953,58 @@ void QgsCircularStringV2::insertVertexBetween( int after, int before, int pointO
     mM.insert( before, ( mM[after] + mM[before] ) / 2.0 );
   }
 }
+
+double QgsCircularStringV2::vertexAngle( const QgsVertexId& vId ) const
+{
+  int before = vId.vertex - 1;
+  int vertex = vId.vertex;
+  int after = vId.vertex + 1;
+
+  if ( vId.vertex % 2 != 0 ) // a curve vertex
+  {
+    if ( vId.vertex >= 1 && vId.vertex < numPoints() - 1 )
+    {
+      return QgsGeometryUtils::circleTangentDirection( QgsPointV2( mX[vertex], mY[vertex] ), QgsPointV2( mX[before], mY[before] ),
+             QgsPointV2( mX[vertex], mY[vertex] ), QgsPointV2( mX[after], mY[after] ) );
+    }
+  }
+  else //a point vertex
+  {
+    if ( vId.vertex == 0 )
+    {
+      return QgsGeometryUtils::circleTangentDirection( QgsPointV2( mX[0], mY[0] ), QgsPointV2( mX[0], mY[0] ),
+             QgsPointV2( mX[1], mY[1] ), QgsPointV2( mX[2], mY[2] ) );
+    }
+    if ( vId.vertex >= numPoints() - 1 )
+    {
+      if ( numPoints() < 3 )
+      {
+        return 0.0;
+      }
+      int a = numPoints() - 3;
+      int b = numPoints() - 2;
+      int c = numPoints() - 1;
+      return QgsGeometryUtils::circleTangentDirection( QgsPointV2( mX[c], mY[c] ), QgsPointV2( mX[a], mY[a] ),
+             QgsPointV2( mX[b], mY[b] ), QgsPointV2( mX[c], mY[c] ) );
+    }
+    else
+    {
+      if ( vId.vertex + 2 > numPoints() - 1 )
+      {
+        return 0.0;
+      }
+
+      int vertex1 = vId.vertex - 2;
+      int vertex2 = vId.vertex - 1;
+      int vertex3 = vId.vertex;
+      double angle1 = QgsGeometryUtils::circleTangentDirection( QgsPointV2( mX[vertex3], mY[vertex3] ),
+                      QgsPointV2( mX[vertex1], mY[vertex1] ), QgsPointV2( mX[vertex2], mY[vertex2] ), QgsPointV2( mX[vertex3], mY[vertex3] ) );
+      int vertex4 = vId.vertex + 1;
+      int vertex5 = vId.vertex + 2;
+      double angle2 = QgsGeometryUtils::circleTangentDirection( QgsPointV2( mX[vertex3], mY[vertex3] ),
+                      QgsPointV2( mX[vertex3], mY[vertex3] ), QgsPointV2( mX[vertex4], mY[vertex4] ), QgsPointV2( mX[vertex5], mY[vertex5] ) );
+      return QgsGeometryUtils::averageAngle( angle1, angle2 );
+    }
+  }
+  return 0.0;
+}