Add public transform method

qgis · Feb 21, 2021 · ef78bf9 · ef78bf9
1 parent 30245ee
commit ef78bf9
Show file tree

Hide file tree

Showing 4 changed files with 37 additions and 10 deletions.
diff --git a/python/analysis/auto_generated/georeferencing/qgsgcptransformer.sip.in b/python/analysis/auto_generated/georeferencing/qgsgcptransformer.sip.in
@@ -65,6 +65,15 @@ Returns the minimum number of Ground Control Points (GCPs) required for paramete
     virtual TransformMethod method() const = 0;
 %Docstring
 Returns the transformation method.
+%End
+
+    bool transform( double &x /In,Out/, double &y /In,Out/, bool inverseTransform = false ) const;
+%Docstring
+Transforms the point (``x``, ``y``) from source to destination coordinates.
+
+If ``inverseTransform`` is set to ``True``, the point will be transformed from the destination to the source.
+
+:return: ``True`` if transformation was successful.
 %End
 
     static QString methodToString( TransformMethod method );

diff --git a/src/analysis/georeferencing/qgsgcptransformer.cpp b/src/analysis/georeferencing/qgsgcptransformer.cpp
@@ -26,6 +26,24 @@
 #include <limits>
 
 
+bool QgsGcpTransformerInterface::transform( double &x, double &y, bool inverseTransform ) const
+{
+  GDALTransformerFunc t = GDALTransformer();
+  // Fail if no transformer function was returned
+  if ( !t )
+    return false;
+
+  double z = 0.0;
+  int success = 0;
+
+  // Call GDAL transform function
+  ( *t )( GDALTransformerArgs(), inverseTransform ? 1 : 0, 1,  &x, &y, &z, &success );
+  if ( !success )
+    return false;
+
+  return true;
+}
+
 QString QgsGcpTransformerInterface::methodToString( QgsGcpTransformerInterface::TransformMethod method )
 {
   switch ( method )

diff --git a/src/analysis/georeferencing/qgsgcptransformer.h b/src/analysis/georeferencing/qgsgcptransformer.h
@@ -84,6 +84,15 @@ class ANALYSIS_EXPORT QgsGcpTransformerInterface SIP_ABSTRACT
      */
     virtual TransformMethod method() const = 0;
 
+    /**
+     * Transforms the point (\a x, \a y) from source to destination coordinates.
+     *
+     * If \a inverseTransform is set to TRUE, the point will be transformed from the destination to the source.
+     *
+     * \returns TRUE if transformation was successful.
+     */
+    bool transform( double &x SIP_INOUT, double &y SIP_INOUT, bool inverseTransform = false ) const;
+
     /**
      * Returns a translated string representing the specified transform \a method.
      */

diff --git a/src/app/georeferencer/qgsgeoreftransform.cpp b/src/app/georeferencer/qgsgeoreftransform.cpp
@@ -188,20 +188,11 @@ bool QgsGeorefTransform::getOriginScaleRotation( QgsPointXY &origin, double &sca
 
 bool QgsGeorefTransform::gdal_transform( const QgsPointXY &src, QgsPointXY &dst, int dstToSrc ) const
 {
-  GDALTransformerFunc t = GDALTransformer();
-  // Fail if no transformer function was returned
-  if ( !t )
-    return false;
-
   // Copy the source coordinate for inplace transform
   double x = src.x();
   double y = src.y();
-  double z = 0.0;
-  int success = 0;
 
-  // Call GDAL transform function
-  ( *t )( GDALTransformerArgs(), dstToSrc, 1,  &x, &y, &z, &success );
-  if ( !success )
+  if ( !QgsGcpTransformerInterface::transform( x, y, dstToSrc == 1 ) )
     return false;
 
   dst.setX( x );