diff --git a/TODO b/TODO
index 95cdb1ae..9c05080c 100644
--- a/TODO
+++ b/TODO
@@ -1,22 +1,16 @@
-- nip2-7.22.3 on Windows is not adding the path you load from to the set opf
+- we need to have separate sources for scanlines and for other sources
+
+  name scanlines sources as "sl0" onwards
+
+  name regular sources as "s1" onwards
+
+
+
+
+
+- nip2-7.22.3 on Windows is not adding the path you load from to the set of
   paths to search, breaking demo2 for Hamish
 
-- custom morph, erode, apply 3 times, lock up!
-
-  4way3.mor
-
-	7 7 1 0
-	128 128 128 255 128 128 128 
-	128 128 255 255 255 128 128 
-	128 255 255 255 255 255 128 
-	255 255 255 255 255 255 255 
-	128 255 255 255 255 255 128 
-	128 128 255 255 255 128 128 
-	128 128 128 255 128 128 128 
-
-  	$ vips im_erode wtc1bit.v t2.v 4way3.mor
-
-  lock up
 
 - lab [100,0,0] -> srgb [255, 255, 254]? how odd
 
diff --git a/libvips/arithmetic/im_add.c b/libvips/arithmetic/im_add.c
index 6a0b55d8..facfc7a5 100644
--- a/libvips/arithmetic/im_add.c
+++ b/libvips/arithmetic/im_add.c
@@ -98,11 +98,13 @@ add_buffer( PEL **in, PEL *out, int width, IMAGE *im )
 
 	if( vips_vector_get_enabled() && 
 		add_vectors[im->BandFmt] ) {
+		VipsVector *vector = add_vectors[im->BandFmt];
+
 		VipsExecutor ex;
 
-		vips_executor_set_program( &ex, add_vectors[im->BandFmt], sz );
-		vips_executor_set_array( &ex, "s1", in[0] );
-		vips_executor_set_array( &ex, "s2", in[1] );
+		vips_executor_set_program( &ex, vector, sz );
+		vips_executor_set_array( &ex, vector->s[0], in[0] );
+		vips_executor_set_array( &ex, vector->s[1], in[1] );
 		vips_executor_set_destination( &ex, out );
 
 		vips_executor_run( &ex );
diff --git a/libvips/include/vips/vector.h b/libvips/include/vips/vector.h
index 51c7530a..6a47cd82 100644
--- a/libvips/include/vips/vector.h
+++ b/libvips/include/vips/vector.h
@@ -57,11 +57,15 @@ typedef struct {
 	int n_parameter;
 	int n_instruction;
 
-	/* The scanlines this pass needs, and the variables each needs to be
-	 * put into. 
+	/* The sources this program needs. "s1"'s var is always in s[0],
+	 * others may skip lines. 
 	 */
+	int s[10];
 	int line[10]; 		
-	int var[10];
+
+	/* The destination var.
+	 */
+	int d1;
 
 #ifdef HAVE_ORC
         /* The code we have generated.
@@ -97,7 +101,7 @@ VipsVector *vips_vector_new_ds( const char *name, int size1, int size2 );
 
 void vips_vector_constant( VipsVector *vector, 
 	char *name, int value, int size );
-void vips_vector_source_name( VipsVector *vector, char *name, int size );
+int vips_vector_source_name( VipsVector *vector, char *name, int size );
 void vips_vector_source( VipsVector *vector, char *name, int number, int size );
 void vips_vector_temporary( VipsVector *vector, char *name, int size );
 void vips_vector_asm2( VipsVector *vector, 
@@ -115,7 +119,7 @@ void vips_executor_set_program( VipsExecutor *executor,
 void vips_executor_set_source( VipsExecutor *executor, 
 	REGION *ir, int x, int y );
 void vips_executor_set_destination( VipsExecutor *executor, void *value );
-void vips_executor_set_array( VipsExecutor *executor, char *name, void *value );
+void vips_executor_set_array( VipsExecutor *executor, int var, void *value );
 
 void vips_executor_run( VipsExecutor *executor );
 
diff --git a/libvips/iofuncs/vector.c b/libvips/iofuncs/vector.c
index 8adccde0..5ca8085f 100644
--- a/libvips/iofuncs/vector.c
+++ b/libvips/iofuncs/vector.c
@@ -125,11 +125,12 @@ vips_vector_new_ds( const char *name, int size1, int size2 )
 {
 	int var;
 
-	/* We always make s1.
+	/* We always make s1 / d1
 	 */
 	var = orc_program_find_var_by_name( vector->program, "s1" );
 	vector->var[0] = var;
 	vector->line[0] = 0;
+	vector->d1 = orc_program_find_var_by_name( vector->program, "d1" );
 }
 #endif /*HAVE_ORC*/
 	vector->n_source += 1;
@@ -206,9 +207,10 @@ vips_vector_source_name( VipsVector *vector, char *name, int size )
 #ifdef HAVE_ORC
 	g_assert( orc_program_find_var_by_name( vector->program, name ) == -1 );
 
-	orc_program_add_source( vector->program, size, name );
+	var = orc_program_add_source( vector->program, size, name );
+	vector->var[vector->n_source] = var;
 	vector->n_source += 1;
-#endif /*HAVE_ORC*/
+#else /*!HAVE_ORC*/
 }
 
 void
@@ -218,15 +220,8 @@ vips_vector_source( VipsVector *vector, char *name, int line, int size )
 	im_snprintf( name, 256, "s%d", line );
 
 	if( orc_program_find_var_by_name( vector->program, name ) == -1 ) {
-		int var;
-		int i;
-
 		vips_vector_source_name( vector, name, size ); 
-
-		i = vector->n_source - 1;
-		var = orc_program_find_var_by_name( vector->program, name );
-		vector->var[i] = var;
-		vector->line[i] = line - 1;
+		vector->line[n_source - 1] = line - 1;
 	}
 #endif /*HAVE_ORC*/
 }
@@ -330,19 +325,21 @@ void
 vips_executor_set_destination( VipsExecutor *executor, void *value )
 {
 #ifdef HAVE_ORC
-	orc_executor_set_array_str( &executor->executor, "d1", value );
+	VipsVector *vector = executor->vector;
+
+	orc_executor_set_array( &executor->executor, vector->d1, value );
 #endif /*HAVE_ORC*/
 }
 
 void
-vips_executor_set_array( VipsExecutor *executor, char *name, void *value )
+vips_executor_set_array( VipsExecutor *executor, int var, void *value )
 {
 #ifdef HAVE_ORC
 	VipsVector *vector = executor->vector;
 	OrcProgram *program = vector->program;
 
-	if( orc_program_find_var_by_name( program, name ) != -1 ) 
-		orc_executor_set_array_str( &executor->executor, name, value );
+	if( var != -1 ) 
+		orc_executor_set_array( &executor->executor, var, value );
 #endif /*HAVE_ORC*/
 }
 
diff --git a/libvips/morphology/morphology.c b/libvips/morphology/morphology.c
index 9475ebe6..e0619abe 100644
--- a/libvips/morphology/morphology.c
+++ b/libvips/morphology/morphology.c
@@ -86,6 +86,9 @@ typedef struct {
 	 */
         VipsVector *vector;
 
+	/* The variable number for r, if we set it (or -1).
+	 */
+	int r;
 } Pass;
 
 /* Our parameters.
@@ -155,13 +158,13 @@ pass_compile_section( Morph *morph, int first, int *last )
 	pass = &morph->pass[morph->n_pass];
 	morph->n_pass += 1;
 	pass->first = first;
+	pass->r = -1;
 
 	/* Start with a single source scanline, we add more as we need them.
 	 */
 	pass->vector = v = vips_vector_new_ds( "morph", 1, 1 );
 
-	/* The value we fetch from the image, 
-	 * the accumulated sum.
+	/* The value we fetch from the image, the accumulated sum.
 	 */
 	TEMP( "value", 1 );
 	TEMP( "sum", 1 );
@@ -182,7 +185,7 @@ pass_compile_section( Morph *morph, int first, int *last )
 	else {
 		/* "r" is the result of the previous pass.
 		 */
-		vips_vector_source_name( v, "r", 1 );
+		pass->r = vips_vector_source_name( v, "r", 1 );
 		ASM2( "loadb", "sum", "r" );
 	}
 
@@ -197,7 +200,7 @@ pass_compile_section( Morph *morph, int first, int *last )
 
 		/* The source. s1 is the first scanline in the mask.
 		 */
-		vips_vector_source( v, source, y + 1, 1 );
+		SRC( source, y + 1, 1 );
 
 		/* The offset, only for non-first-columns though.
 		 */
@@ -674,11 +677,12 @@ morph_vector_gen( REGION *or, void *vseq, void *a, void *b )
 			else 
 				d = seq->t2;
 
-			vips_executor_set_source( executor, 
+			vips_executor_set_source( &executor[j], 
 				ir, r->left, r->top + y );
-			vips_executor_set_array( executor, "r", seq->t1 );
-			vips_executor_set_array( executor, "d1", d );
-			vips_executor_run( executor );
+			vips_executor_set_array( &executor[j].executor,
+				morph->pass[j].r, seq->t1 );
+			vips_executor_set_destination( &executor[j], d );
+			vips_executor_run( &executor[j] );
 
 			IM_SWAP( void *, seq->t1, seq->t2 );
 		}