[Geometry checker] Make line intersection test and line layer interse…

…ction test also report multiple intersections for same line
qgis · Oct 23, 2017 · baf4a39c684dcc948c49204600075560a3ae032f · baf4a39
1 parent 5ded4f8
commit baf4a39c684dcc948c49204600075560a3ae032f
diff --git a/src/analysis/vector/geometry_checker/qgsgeometrycheckerutils.cpp b/src/analysis/vector/geometry_checker/qgsgeometrycheckerutils.cpp
@@ -253,23 +253,25 @@ namespace QgsGeometryCheckerUtils
     return false;
   }
 
-  bool linesIntersect( const QgsLineString *line1, const QgsLineString *line2, double tol, QgsPoint &inter )
+  QList<QgsPoint> lineIntersections( const QgsLineString *line1, const QgsLineString *line2, double tol )
   {
+    QList<QgsPoint> intersections;
+    QgsPoint inter;
     for ( int i = 0, n = line1->vertexCount() - 1; i < n; ++i )
     {
       for ( int j = 0, m = line2->vertexCount() - 1; j < m; ++j )
       {
         QgsPoint p1 = line1->vertexAt( QgsVertexId( 0, 0, i ) );
         QgsPoint p2 = line1->vertexAt( QgsVertexId( 0, 0, i + 1 ) );
-        QgsPoint q1 = line1->vertexAt( QgsVertexId( 0, 0, j ) );
-        QgsPoint q2 = line1->vertexAt( QgsVertexId( 0, 0, j + 1 ) );
+        QgsPoint q1 = line2->vertexAt( QgsVertexId( 0, 0, j ) );
+        QgsPoint q2 = line2->vertexAt( QgsVertexId( 0, 0, j + 1 ) );
         if ( QgsGeometryUtils::segmentIntersection( p1, p2, q1, q2, inter, tol ) )
         {
-          return true;
+          intersections.append( inter );
         }
       }
     }
-    return false;
+    return intersections;
   }
 
   double sharedEdgeLength( const QgsAbstractGeometry *geom1, const QgsAbstractGeometry *geom2, double tol )

diff --git a/src/analysis/vector/geometry_checker/qgsgeometrycheckerutils.h b/src/analysis/vector/geometry_checker/qgsgeometrycheckerutils.h
@@ -133,7 +133,7 @@ namespace QgsGeometryCheckerUtils
 
   bool pointOnLine( const QgsPoint &p, const QgsLineString *line, double tol, bool excludeExtremities = false );
 
-  bool linesIntersect( const QgsLineString *line1, const QgsLineString *line2, double tol, QgsPoint &inter );
+  QList<QgsPoint> lineIntersections( const QgsLineString *line1, const QgsLineString *line2, double tol );
 
   double sharedEdgeLength( const QgsAbstractGeometry *geom1, const QgsAbstractGeometry *geom2, double tol );
 

diff --git a/src/analysis/vector/geometry_checker/qgsgeometrylineintersectioncheck.cpp b/src/analysis/vector/geometry_checker/qgsgeometrylineintersectioncheck.cpp
@@ -59,10 +59,9 @@ void QgsGeometryLineIntersectionCheck::collectErrors( QList<QgsGeometryCheckErro
           {
             continue;
           }
-          QgsPoint inter;
-          if ( QgsGeometryCheckerUtils::linesIntersect( line, testLine, mContext->tolerance, inter ) )
+          for ( const QgsPoint &inter : QgsGeometryCheckerUtils::lineIntersections( line, testLine, mContext->tolerance ) )
           {
-            errors.append( new QgsGeometryCheckError( this, layerFeature, inter ) );
+            errors.append( new QgsGeometryCheckError( this, layerFeatureA, inter, QgsVertexId(), layerFeatureB.id() ) );
           }
         }
       }

diff --git a/src/analysis/vector/geometry_checker/qgsgeometrylinelayerintersectioncheck.cpp b/src/analysis/vector/geometry_checker/qgsgeometrylinelayerintersectioncheck.cpp
@@ -42,22 +42,21 @@ void QgsGeometryLineLayerIntersectionCheck::collectErrors( QList<QgsGeometryChec
         const QgsAbstractGeometry *testGeom = checkFeature.geometry();
         for ( int jPart = 0, mParts = testGeom->partCount(); jPart < mParts; ++jPart )
         {
-          QgsPoint inter;
           const QgsAbstractGeometry *part = QgsGeometryCheckerUtils::getGeomPart( testGeom, jPart );
           if ( const QgsLineString *testLine = dynamic_cast<const QgsLineString *>( part ) )
           {
-            if ( QgsGeometryCheckerUtils::linesIntersect( line, testLine, mContext->tolerance, inter ) )
+            for ( const QgsPoint &inter : QgsGeometryCheckerUtils::lineIntersections( line, testLine, mContext->tolerance ) )
             {
-              errors.append( new QgsGeometryCheckError( this, layerFeature, inter ) );
+              errors.append( new QgsGeometryCheckError( this, layerFeature, inter, QgsVertexId(), checkFeature.id() ) );
             }
           }
           else if ( const QgsPolygonV2 *polygon = dynamic_cast<const QgsPolygonV2 *>( part ) )
           {
             for ( const QgsLineString *ring : QgsGeometryCheckerUtils::polygonRings( polygon ) )
             {
-              if ( QgsGeometryCheckerUtils::linesIntersect( ring, testLine, mContext->tolerance, inter ) )
+              for ( const QgsPoint &inter : QgsGeometryCheckerUtils::lineIntersections( line, ring, mContext->tolerance ) )
               {
-                errors.append( new QgsGeometryCheckError( this, layerFeature, inter ) );
+                errors.append( new QgsGeometryCheckError( this, layerFeature, inter, QgsVertexId(), checkFeature.id() ) );
               }
             }
           }