[QGIS Commit] r15697 - trunk/qgis/src/core

[svn_qgis at osgeo.org]

Author: rblazek
Date: 2011-04-13 11:04:31 -0700 (Wed, 13 Apr 2011)
New Revision: 15697

Modified:
   trunk/qgis/src/core/qgsrasterprojector.cpp
   trunk/qgis/src/core/qgsrasterprojector.h
Log:
fall to precise reprojection if thresh wasnt reached

Modified: trunk/qgis/src/core/qgsrasterprojector.cpp
===================================================================
--- trunk/qgis/src/core/qgsrasterprojector.cpp	2011-04-13 07:03:14 UTC (rev 15696)
+++ trunk/qgis/src/core/qgsrasterprojector.cpp	2011-04-13 18:04:31 UTC (rev 15697)
@@ -80,6 +80,7 @@
     if ( myColsOK && myRowsOK )
     {
       QgsDebugMsg( "CP matrix within tolerance" );
+      mApproximate = true;
       break;
     }
     // What is the maximum reasonable size of transformatio matrix?
@@ -87,6 +88,7 @@
     if ( mCPRows * mCPCols > 0.25 * mDestRows * mDestCols )
     {
       QgsDebugMsg( "Too large CP matrix" );
+      mApproximate = false;
       break;
     }
 
@@ -293,6 +295,29 @@
 
 void QgsRasterProjector::srcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol )
 {
+  if ( mApproximate ) approximateSrcRowCol( theDestRow, theDestCol, theSrcRow, theSrcCol);
+  else preciseSrcRowCol( theDestRow, theDestCol, theSrcRow, theSrcCol);
+}
+
+void QgsRasterProjector::preciseSrcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol )
+{
+  // Get coordinate of center of destination cell
+  double x = mDestExtent.xMinimum() + ( theDestCol + 0.5 ) * mDestXRes;
+  double y = mDestExtent.yMaximum() - ( theDestRow + 0.5 ) * mDestYRes;
+  double z = 0;
+  
+  mCoordinateTransform.transformInPlace( x, y, z );
+  
+  // Get source row col
+  *theSrcRow = ( int ) floor(( mSrcExtent.yMaximum() - y ) / mSrcXRes );
+  *theSrcCol = ( int ) floor(( x - mSrcExtent.xMinimum() ) / mSrcYRes );
+
+  assert( *theSrcRow < mSrcRows );
+  assert( *theSrcCol < mSrcCols );
+}
+
+void QgsRasterProjector::approximateSrcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol )
+{
   int myMatrixRow = matrixRow( theDestRow );
   int myMatrixCol = matrixCol( theDestCol );
 

Modified: trunk/qgis/src/core/qgsrasterprojector.h
===================================================================
--- trunk/qgis/src/core/qgsrasterprojector.h	2011-04-13 07:03:14 UTC (rev 15696)
+++ trunk/qgis/src/core/qgsrasterprojector.h	2011-04-13 18:04:31 UTC (rev 15697)
@@ -69,6 +69,12 @@
     /** \brief get destination point for _current_ matrix position */
     QgsPoint srcPoint( int theRow, int theCol );
 
+    /** \brief Get precise source row and column indexes for current source extent and resolution */
+    inline void preciseSrcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol );
+
+    /** \brief Get approximate source row and column indexes for current source extent and resolution */
+    inline void approximateSrcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol );
+
     /** \brief Get source row and column indexes for current source extent and resolution */
     void srcRowCol( int theDestRow, int theDestCol, int *theSrcRow, int *theSrcCol );
 
@@ -194,6 +200,9 @@
     /** Maximum source resolution */
     double mMaxSrcXRes;
     double mMaxSrcYRes;
+    
+    /** Use approximation */
+    bool mApproximate;
 };
 
 #endif