transfer: allow optional extrapolation

1 files changed, 6 insertions, 0 deletions

diff --git a/transfer.h b/transfer.h
index 0a10f3a..2ed4aea 100644
--- a/transfer.h
+++ b/transfer.h
@@ -85,6 +85,12 @@ typedef struct GridTransferContext {
      * Destination grid geometry, must be filled by the caller.
      */
     RegularGrid2D dst;
+
+    /**
+     * Allow extrapolating this many points beyond the source rectangle.
+     * Defaults to 0: forbid extrapolation.
+     */
+    int extrapolate_distance;
 } GridTransferContext;
 
 /**