From 5c4446dd5ecc0993c429f5c94ef90c322a90ea1f Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 31 Jul 2006 20:56:22 +0000
Subject: [PATCH] From Jason Beverage, "I've attached fixes to DataSet that
 should fix the problems that Maya was seeing yesterday.  The issue was that
 the new interpolation code I submitted didn't use the SourceData's georef, it
 was assuming that the GDALDataSet had a proper geo-ref.  I've made the
 getInterpolatedValue method a member of SourceData and now it uses the georef
 the SourceData's georef.

I also forward declared the GDALRasterBand class in the DataSet header."
---
 include/osgTerrain/DataSet |  3 +++
 src/osgTerrain/DataSet.cpp | 35 +++++++++++++++++++++--------------
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/include/osgTerrain/DataSet b/include/osgTerrain/DataSet
index 75cc24a5f..b49377916 100644
--- a/include/osgTerrain/DataSet
+++ b/include/osgTerrain/DataSet
@@ -41,6 +41,7 @@
 
 // forward declare so we can avoid tieing osgTerrain to GDAL.
 class GDALDataset;
+class GDALRasterBand;
 
 namespace osgTerrain
 {
@@ -248,6 +249,8 @@ class OSGTERRAIN_EXPORT DataSet : public osg::Referenced
             virtual void readHeightField(DestinationData& destination);
             virtual void readModels(DestinationData& destination);
 
+            float getInterpolatedValue(GDALRasterBand *band, double x, double y);
+
             Source*                                     _source;
             
             bool                                        _hasGCPs;
diff --git a/src/osgTerrain/DataSet.cpp b/src/osgTerrain/DataSet.cpp
index 550acc8ba..d1c7ce584 100644
--- a/src/osgTerrain/DataSet.cpp
+++ b/src/osgTerrain/DataSet.cpp
@@ -212,22 +212,32 @@ bool areCoordinateSystemEquivalent(const osg::CoordinateSystemNode* lhs,const os
          return result ? true : false;
 }
 
-float getInterpolatedValue(GDALRasterBand *band, double x, double y)
+
+
+DataSet::SourceData::~SourceData()
+{
+    if (_gdalDataset) GDALClose(_gdalDataset);
+}
+
+float DataSet::SourceData::getInterpolatedValue(GDALRasterBand *band, double x, double y)
 {
     double geoTransform[6];
-    band->GetDataset()->GetGeoTransform(geoTransform);
+    geoTransform[0] = _geoTransform(3,0);
+    geoTransform[1] = _geoTransform(0,0);
+    geoTransform[2] = _geoTransform(1,0);
+    geoTransform[3] = _geoTransform(3,1);
+    geoTransform[4] = _geoTransform(0,1);
+    geoTransform[5] = _geoTransform(1,1);
+
     double invTransform[6];
     GDALInvGeoTransform(geoTransform, invTransform);
     double r, c;
     GDALApplyGeoTransform(invTransform, x, y, &c, &r);
-
-    int numRows = band->GetYSize();
-    int numCols = band->GetXSize();
-
+   
     int rowMin = osg::maximum((int)floor(r), 0);
-    int rowMax = osg::maximum(osg::minimum((int)ceil(r), numRows-1), 0);
+    int rowMax = osg::maximum(osg::minimum((int)ceil(r), (int)(_numValuesY-1)), 0);
     int colMin = osg::maximum((int)floor(c), 0);
-    int colMax = osg::maximum(osg::minimum((int)ceil(c), numCols-1), 0);
+    int colMax = osg::maximum(osg::minimum((int)ceil(c), (int)(_numValuesX-1)), 0);
 
     if (rowMin > rowMax) rowMin = rowMax;
     if (colMin > colMax) colMin = colMax;
@@ -256,13 +266,10 @@ float getInterpolatedValue(GDALRasterBand *band, double x, double y)
     double w01 = (1.0 - y_rem) * x_rem * (double)lrHeight;
     double w10 = y_rem * (1.0 - x_rem) * (double)ulHeight;
     double w11 = y_rem * x_rem * (double)urHeight;
-    float result = (float)(w00 + w01 + w10 + w11);
-    return result;
-}
 
-DataSet::SourceData::~SourceData()
-{
-    if (_gdalDataset) GDALClose(_gdalDataset);
+    float result = (float)(w00 + w01 + w10 + w11);
+
+    return result;
 }
 
 DataSet::SourceData* DataSet::SourceData::readData(Source* source)