IH5Dataset: Fix API changes to Get/SetGeoTransform methods in GDAL 3.12 (#196)

* `IH5Dataset`: Fix changes to `GeoTransform` methods in GDAL 3.12

GDAL 3.12 introduced a breaking API change:
`GetGeoTransform()` and `SetGeoTransform()` methods now use a
`GDALGeoTransform` class instead of raw double* arrays.

This patch adds conditional compilation to support both the new GDAL 3.12+ API and older versions.

See https://gdal.org/en/stable/user/migration_guide.html

* Relax thresholds for geocodeCov checkStatsReal

Author: scottstanie

cxx/isce3/io/IH5Dataset.cpp

@@ -385,27 +385,56 @@ void * IH5Dataset::GetInternalHandle(const char *)
 /*                          GetGeoTransform()                           */
 /************************************************************************/
 
-CPLErr IH5Dataset::GetGeoTransform( double *padfGeoTransform )
+#if GDAL_VERSION_MAJOR >= 4 || (GDAL_VERSION_MAJOR == 3 && GDAL_VERSION_MINOR >= 12)
+// GDAL 3.12+ API using GDALGeoTransform class
+CPLErr IH5Dataset::GetGeoTransform( GDALGeoTransform &gt ) const
 {
-    memcpy( padfGeoTransform, adfGeoTransform, sizeof(double) * 6 );
+    gt = GDALGeoTransform(adfGeoTransform);
     if( bGeoTransformSet )
         return CE_None;
 
     return CE_Failure;
 }
+#else
+// GDAL < 3.12 API using double array
+CPLErr IH5Dataset::GetGeoTransform( double *padfTransform )
+{
+    memcpy(padfTransform, adfGeoTransform, sizeof(double) * 6);
+    if( bGeoTransformSet )
+        return CE_None;
+
+    return CE_Failure;
+}
+#endif
 
 /************************************************************************/
 /*                          SetGeoTransform()                           */
 /************************************************************************/
 
-CPLErr IH5Dataset::SetGeoTransform( double *padfGeoTransform )
+#if GDAL_VERSION_MAJOR >= 4 || (GDAL_VERSION_MAJOR == 3 && GDAL_VERSION_MINOR >= 12)
+// GDAL 3.12+ API using GDALGeoTransform class
+CPLErr IH5Dataset::SetGeoTransform( const GDALGeoTransform &gt )
+{
+    adfGeoTransform[0] = gt.xorig;
+    adfGeoTransform[1] = gt.xscale;
+    adfGeoTransform[2] = gt.xrot;
+    adfGeoTransform[3] = gt.yorig;
+    adfGeoTransform[4] = gt.yrot;
+    adfGeoTransform[5] = gt.yscale;
+    bGeoTransformSet = TRUE;
 
+    return CE_None;
+}
+#else
+// GDAL < 3.12 API using double array
+CPLErr IH5Dataset::SetGeoTransform( double *padfTransform )
 {
-    memcpy( adfGeoTransform, padfGeoTransform, sizeof(double) * 6 );
+    memcpy(adfGeoTransform, padfTransform, sizeof(double) * 6);
     bGeoTransformSet = TRUE;
 
     return CE_None;
 }
+#endif
 
 /************************************************************************/
 /*                            GetGCPCount()                             */

cxx/isce3/io/IH5Dataset.h

@@ -11,6 +11,7 @@
 #include <gdal_pam.h>
 #include <gdal_priv.h>
 #include <gdal_rat.h>
+#include <gdal_version.h>
 #include "IH5.h"
 
 
@@ -62,8 +63,13 @@ class IH5Dataset final: public GDALDataset
 
         void *GetInternalHandle (const char *) override;
 
+#if GDAL_VERSION_MAJOR >= 4 || (GDAL_VERSION_MAJOR == 3 && GDAL_VERSION_MINOR >= 12)
+        virtual CPLErr GetGeoTransform( GDALGeoTransform &gt ) const override;
+        virtual CPLErr SetGeoTransform( const GDALGeoTransform &gt ) override;
+#else
         virtual CPLErr GetGeoTransform( double *padfTransform ) override;
-        virtual CPLErr SetGeoTransform( double * ) override;
+        virtual CPLErr SetGeoTransform( double *padfTransform ) override;
+#endif
         static GDALDataset *Open(GDALOpenInfo *info);
         static int Identify(GDALOpenInfo *info);
 };

tests/cxx/isce3/geocode/geocodeCov.cpp

@@ -630,10 +630,10 @@ void checkStatsReal(isce3::math::Stats<T> computed_stats,
         std::cout << "n_valid: " << isce3_stats.n_valid << ", " << computed_stats.n_valid << std::endl;
 
         // Compare Stats struct values with GDAL metadata saved by GeocodeCov
-        ASSERT_NEAR(isce3_stats.min, raster_min, 1.0e-15);
-        ASSERT_NEAR(isce3_stats.mean, raster_mean, 1.0e-15);
-        ASSERT_NEAR(isce3_stats.max, raster_max, 1.0e-15);
-        ASSERT_NEAR(isce3_stats.sample_stddev(), raster_sample_stddev, 1.0e-15);
+        ASSERT_NEAR(isce3_stats.min, raster_min, 1.0e-12);
+        ASSERT_NEAR(isce3_stats.mean, raster_mean, 1.0e-12);
+        ASSERT_NEAR(isce3_stats.max, raster_max, 1.0e-12);
+        ASSERT_NEAR(isce3_stats.sample_stddev(), raster_sample_stddev, 1.0e-12);
 
         // Compare Stats struct values with unitest values
         ASSERT_NEAR(isce3_stats.min, computed_stats.min, 1.0e-7);