From 3f1c8551774c827c7124ec6b37c30aa4f23e6a6e Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Wed, 25 May 2011 13:25:18 +0100
Subject: [PATCH] vipsinterpolate uses new_from_string() vfunc system

---
 libvips/include/vips/object.h  |  5 +++--
 libvips/resample/interpolate.c | 27 +++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/libvips/include/vips/object.h b/libvips/include/vips/object.h
index 24435863..084a4d51 100644
--- a/libvips/include/vips/object.h
+++ b/libvips/include/vips/object.h
@@ -266,8 +266,9 @@ struct _VipsObjectClass {
 	 */
 
 	/* Given a command-line arg (eg. a filename), make an instance of the
-	 * object. Don't call this directly, see
-	 * vips_object_new_from_string().
+	 * object. Just do the g_object_new(), don't call _build().
+	 *
+	 * Don't call this directly, see vips_object_new_from_string().
 	 */
 	VipsObject *(*new_from_string)( const char *string );
 
diff --git a/libvips/resample/interpolate.c b/libvips/resample/interpolate.c
index 72dee26c..92d41e99 100644
--- a/libvips/resample/interpolate.c
+++ b/libvips/resample/interpolate.c
@@ -167,16 +167,43 @@ vips_interpolate_real_get_window_offset( VipsInterpolate *interpolate )
 	}
 }
 
+static VipsObject * 
+vips_interpolate_new_from_string( const char *string )
+{
+	GType type;
+
+	/* The main arg selects the subclass.
+	 */
+	if( !(type = vips_type_find( "VipsInterpolate", string )) )
+		return( NULL );
+	return( VIPS_OBJECT( g_object_new( type, NULL ) ) );
+}
+
+static void 
+vips_interpolate_to_string( VipsObject *object, VipsBuf *buf )
+{
+	VipsObjectClass *class = VIPS_OBJECT_GET_CLASS( object );
+
+	/* Just "bicubic" or whatever.
+	 */
+	vips_buf_appends( buf, class->nickname );
+}
+
 static void
 vips_interpolate_class_init( VipsInterpolateClass *class )
 {
 #ifdef DEBUG
 	GObjectClass *gobject_class = G_OBJECT_CLASS( class );
 #endif /*DEBUG*/
+	VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS( class );
 
 #ifdef DEBUG
 	gobject_class->finalize = vips_interpolate_finalize;
 #endif /*DEBUG*/
+
+	vobject_class->new_from_string = vips_interpolate_new_from_string;
+	vobject_class->to_string = vips_interpolate_to_string;
+
 	class->interpolate = NULL;
 	class->get_window_size = vips_interpolate_real_get_window_size;
 	class->get_window_offset = vips_interpolate_real_get_window_offset;