Extracted CoordTransform.

examples/read_write_ogr.rs

@@ -1,9 +1,10 @@
 use gdal::errors::Result;
-use gdal::spatial_ref::{CoordTransform, SpatialRef};
+use gdal::spatial_ref::SpatialRef;
 use gdal::Dataset;
-use gdal::{vector::*, DriverManager};
+use gdal::{DriverManager, vector::*};
 use std::fs;
 use std::path::Path;
+use gdal::spatial_ref::CoordTransform;
 
 fn run() -> Result<()> {
     let dataset_a = Dataset::open(Path::new("fixtures/roads.geojson"))?;

examples/spatial_reference.rs

@@ -1,5 +1,6 @@
 use gdal::errors::Result;
-use gdal::spatial_ref::{CoordTransform, SpatialRef};
+use gdal::spatial_ref::SpatialRef;
+use gdal::spatial_ref::CoordTransform;
 use gdal::vector::Geometry;
 
 fn run() -> Result<()> {

src/dataset.rs

@@ -438,7 +438,7 @@ impl Dataset {
     #[cfg(major_ge_3)]
     /// Set the spatial reference system for this dataset.
     pub fn set_spatial_ref(&mut self, spatial_ref: &SpatialRef) -> Result<()> {
-        let rv = unsafe { gdal_sys::GDALSetSpatialRef(self.c_dataset, spatial_ref.to_c_hsrs()) };
+        let rv = unsafe { gdal_sys::GDALSetSpatialRef(self.c_dataset, spatial_ref.c_handle()) };
         if rv != CPLErr::CE_None {
             return Err(_last_cpl_err(rv));
         }
@@ -660,10 +660,6 @@ impl Dataset {
     /// ```
     pub fn create_layer(&mut self, options: LayerOptions<'_>) -> Result<Layer> {
         let c_name = CString::new(options.name)?;
-        let c_srs = match options.srs {
-            Some(srs) => srs.to_c_hsrs(),
-            None => null_mut(),
-        };
 
         // Handle string options: we need to keep the CStrings and the pointers around.
         let c_options = options.options.map(|d| {
@@ -686,6 +682,10 @@ impl Dataset {
         };
 
         let c_layer = unsafe {
+            let c_srs = match options.srs {
+                Some(srs) => srs.c_handle(),
+                None => null_mut(),
+            };
             // The C function takes `char **papszOptions` without mention of `const`, and this is
             // propagated to the gdal_sys wrapper. The lack of `const` seems like a mistake in the
             // GDAL API, so we just do a cast here.

src/spatial_ref/mod.rs

@@ -3,7 +3,9 @@
 //! <https://gdal.org/api/ogr_srs_api.html>
 
 mod srs;
+mod transform;
 mod transform_opts;
 
-pub use srs::{AxisOrientationType, CoordTransform, SpatialRef};
-pub use transform_opts::CoordTransformOptions;
+pub use srs::{AxisOrientationType, SpatialRef};
+pub use transform::CoordTransform;
+pub use transform_opts::CoordTransformOptions;