From 036bd0bb4b5ed30ed4451065217ef8fc955ff132 Mon Sep 17 00:00:00 2001
From: John Cupitt <jcupitt@gmail.com>
Date: Sat, 9 Jul 2016 19:20:33 +0100
Subject: [PATCH] convsep calls convasep when it can

---
 TODO                          |  2 ++
 libvips/convolution/convsep.c | 40 +++++++++++++++++++++++------------
 2 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/TODO b/TODO
index 2daa7c23..30791a6c 100644
--- a/TODO
+++ b/TODO
@@ -1,3 +1,5 @@
+- convasep does not handle offset correctly
+
 - test new clip stuff?
 
 - add more webp tests to py suite
diff --git a/libvips/convolution/convsep.c b/libvips/convolution/convsep.c
index 7838ec41..27299c0a 100644
--- a/libvips/convolution/convsep.c
+++ b/libvips/convolution/convsep.c
@@ -63,6 +63,8 @@ vips_convsep_build( VipsObject *object )
 	VipsImage **t = (VipsImage **) 
 		vips_object_local_array( object, 3 );
 
+	VipsImage *in;
+
 	g_object_set( convsep, "out", vips_image_new(), NULL ); 
 
 	if( VIPS_OBJECT_CLASS( vips_convsep_parent_class )->build( object ) )
@@ -71,20 +73,32 @@ vips_convsep_build( VipsObject *object )
 	if( vips_check_separable( class->nickname, convolution->M ) ) 
                 return( -1 );
 
-	if( vips_rot( convolution->M, &t[0], VIPS_ANGLE_D90, NULL ) ||
-		vips_conv( convolution->in, &t[1], convolution->M, 
-			"precision", convsep->precision,
-			"layers", convsep->layers,
-			"cluster", convsep->cluster,
-			NULL ) ||
-		vips_conv( t[1], &t[2], t[0], 
-			"precision", convsep->precision,
-			"layers", convsep->layers,
-			"cluster", convsep->cluster,
-			NULL ) )
-		return( -1 ); 
+	in = convolution->in;
 
-	if( vips_image_write( t[2], convolution->out ) )
+	if( convsep->precision == VIPS_PRECISION_APPROXIMATE ) {
+		if( vips_convasep( convolution->in, &t[0], convolution->M,
+			"layers", convsep->layers,
+			NULL ) )
+			return( -1 ); 
+		in = t[0];
+	}
+	else { 
+		if( vips_rot( convolution->M, &t[0], VIPS_ANGLE_D90, NULL ) ||
+			vips_conv( convolution->in, &t[1], convolution->M, 
+				"precision", convsep->precision,
+				"layers", convsep->layers,
+				"cluster", convsep->cluster,
+				NULL ) ||
+			vips_conv( t[1], &t[2], t[0], 
+				"precision", convsep->precision,
+				"layers", convsep->layers,
+				"cluster", convsep->cluster,
+				NULL ) )
+			return( -1 ); 
+		in = t[2];
+	}
+
+	if( vips_image_write( in, convolution->out ) )
 		return( -1 ); 
 
 	return( 0 );