Add QgsClipper::clippedLine variant which accepts a QPolygonF line

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qgis · Sep 21, 2020 · 9990b84 · 9990b84
1 parent 1c1febc
commit 9990b84
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Showing 3 changed files with 27 additions and 6 deletions.
diff --git a/python/core/auto_generated/qgsclipper.sip.in b/python/core/auto_generated/qgsclipper.sip.in
@@ -75,6 +75,13 @@ Takes a linestring and clips it to clipExtent
 :param clipExtent: clipping bounds
 
 :return: clipped line coordinates
+%End
+
+    static QPolygonF clippedLine( const QPolygonF &curve, const QgsRectangle &clipExtent );
+%Docstring
+Takes a ``curve`` and clips it to clipExtent.
+
+.. versionadded:: 3.16
 %End
 
 };

diff --git a/src/core/qgsclipper.cpp b/src/core/qgsclipper.cpp
@@ -40,7 +40,12 @@ const double QgsClipper::SMALL_NUM = 1e-12;
 
 QPolygonF QgsClipper::clippedLine( const QgsCurve &curve, const QgsRectangle &clipExtent )
 {
-  const int nPoints = curve.numPoints();
+  return clippedLine( curve.asQPolygonF(), clipExtent );
+}
+
+QPolygonF QgsClipper::clippedLine( const QPolygonF &curve, const QgsRectangle &clipExtent )
+{
+  const int nPoints = curve.size();
 
   double p0x, p0y, p1x = 0.0, p1y = 0.0; //original coordinates
   double p1x_c, p1y_c; //clipped end coordinates
@@ -49,21 +54,22 @@ QPolygonF QgsClipper::clippedLine( const QgsCurve &curve, const QgsRectangle &cl
   QPolygonF line;
   line.reserve( nPoints + 1 );
 
+  const QPointF *curveData = curve.data();
+
   for ( int i = 0; i < nPoints; ++i )
   {
     if ( i == 0 )
     {
-      p1x = curve.xAt( i );
-      p1y = curve.yAt( i );
-      continue;
+      p1x = curveData->x();
+      p1y = curveData->y();
     }
     else
     {
       p0x = p1x;
       p0y = p1y;
 
-      p1x = curve.xAt( i );
-      p1y = curve.yAt( i );
+      p1x = curveData->x();
+      p1y = curveData->y();
 
       p1x_c = p1x;
       p1y_c = p1y;
@@ -88,6 +94,7 @@ QPolygonF QgsClipper::clippedLine( const QgsCurve &curve, const QgsRectangle &cl
         line << QPointF( p1x_c,  p1y_c );
       }
     }
+    curveData++;
   }
   return line;
 }

diff --git a/src/core/qgsclipper.h b/src/core/qgsclipper.h
@@ -108,6 +108,13 @@ class CORE_EXPORT QgsClipper
      */
     static QPolygonF clippedLine( const QgsCurve &curve, const QgsRectangle &clipExtent );
 
+    /**
+     * Takes a \a curve and clips it to clipExtent.
+     *
+     * \since QGIS 3.16
+     */
+    static QPolygonF clippedLine( const QPolygonF &curve, const QgsRectangle &clipExtent );
+
   private:
 
     // Used when testing for equivalence to 0.0