BLI_listbase: Add/use utility to move link (BLI_listbase_link_move)

We were calling BLI_remlink and then BLI_insertlinkbefore/after quite often. BLI_listbase_link_move simplifies code a bit and makes it easier to follow. It also returns if link position has changed which can be used to avoid unnecessary updates.

Added it to a number of list reorder operators for now and made use of return value. Behavior shouldn't be changed.

Also some minor cleanup.

14 files changed, 137 insertions, 185 deletions

diff --git a/source/blender/blenkernel/BKE_freestyle.h b/source/blender/blenkernel/BKE_freestyle.h
index e10594634f0..50407f3bdfc 100644
--- a/source/blender/blenkernel/BKE_freestyle.h
+++ b/source/blender/blenkernel/BKE_freestyle.h
@@ -55,8 +55,7 @@ void BKE_freestyle_config_copy(FreestyleConfig *new_config, FreestyleConfig *con
 /* FreestyleConfig.modules */
 FreestyleModuleConfig *BKE_freestyle_module_add(FreestyleConfig *config);
 bool BKE_freestyle_module_delete(FreestyleConfig *config, FreestyleModuleConfig *module_conf);
-bool BKE_freestyle_module_move_up(FreestyleConfig *config, FreestyleModuleConfig *module_conf);
-bool BKE_freestyle_module_move_down(FreestyleConfig *config, FreestyleModuleConfig *module_conf);
+bool BKE_freestyle_module_move(FreestyleConfig *config, FreestyleModuleConfig *module_conf, int direction);
 
 /* FreestyleConfig.linesets */
 FreestyleLineSet *BKE_freestyle_lineset_add(struct Main *bmain, FreestyleConfig *config, const char *name);
diff --git a/source/blender/blenkernel/BKE_linestyle.h b/source/blender/blenkernel/BKE_linestyle.h
index e96ef4e7be3..af9bf58ce77 100644
--- a/source/blender/blenkernel/BKE_linestyle.h
+++ b/source/blender/blenkernel/BKE_linestyle.h
@@ -73,10 +73,10 @@ int BKE_linestyle_alpha_modifier_remove(FreestyleLineStyle *linestyle, LineStyle
 int BKE_linestyle_thickness_modifier_remove(FreestyleLineStyle *linestyle, LineStyleModifier *modifier);
 int BKE_linestyle_geometry_modifier_remove(FreestyleLineStyle *linestyle, LineStyleModifier *modifier);
 
-void BKE_linestyle_color_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
-void BKE_linestyle_alpha_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
-void BKE_linestyle_thickness_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
-void BKE_linestyle_geometry_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
+bool BKE_linestyle_color_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
+bool BKE_linestyle_alpha_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
+bool BKE_linestyle_thickness_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
+bool BKE_linestyle_geometry_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction);
 
 void BKE_linestyle_modifier_list_color_ramps(FreestyleLineStyle *linestyle, ListBase *listbase);
 char *BKE_linestyle_path_to_color_ramp(FreestyleLineStyle *linestyle, struct ColorBand *color_ramp);
diff --git a/source/blender/blenkernel/intern/freestyle.c b/source/blender/blenkernel/intern/freestyle.c
index 3a15be5a09d..21fc1674dc5 100644
--- a/source/blender/blenkernel/intern/freestyle.c
+++ b/source/blender/blenkernel/intern/freestyle.c
@@ -151,22 +151,14 @@ bool BKE_freestyle_module_delete(FreestyleConfig *config, FreestyleModuleConfig
 	return true;
 }
 
-bool BKE_freestyle_module_move_up(FreestyleConfig *config, FreestyleModuleConfig *module_conf)
-{
-	if (BLI_findindex(&config->modules, module_conf) == -1)
-		return false;
-	BLI_remlink(&config->modules, module_conf);
-	BLI_insertlinkbefore(&config->modules, module_conf->prev, module_conf);
-	return true;
-}
-
-bool BKE_freestyle_module_move_down(FreestyleConfig *config, FreestyleModuleConfig *module_conf)
+/**
+ * Reinsert \a module_conf offset by \a direction from current position.
+ * \return if position of \a module_conf changed.
+ */
+bool BKE_freestyle_module_move(FreestyleConfig *config, FreestyleModuleConfig *module_conf, int direction)
 {
-	if (BLI_findindex(&config->modules, module_conf) == -1)
-		return false;
-	BLI_remlink(&config->modules, module_conf);
-	BLI_insertlinkafter(&config->modules, module_conf->next, module_conf);
-	return true;
+	return ((BLI_findindex(&config->modules, module_conf) > -1) &&
+	        (BLI_listbase_link_move(&config->modules, module_conf, direction) == true));
 }
 
 void BKE_freestyle_lineset_unique_name(FreestyleConfig *config, FreestyleLineSet *lineset)
diff --git a/source/blender/blenkernel/intern/linestyle.c b/source/blender/blenkernel/intern/linestyle.c
index 430935a5fad..bd21215f91e 100644
--- a/source/blender/blenkernel/intern/linestyle.c
+++ b/source/blender/blenkernel/intern/linestyle.c
@@ -1343,33 +1343,25 @@ int BKE_linestyle_geometry_modifier_remove(FreestyleLineStyle *linestyle, LineSt
 	return 0;
 }
 
-static void move_modifier(ListBase *lb, LineStyleModifier *modifier, int direction)
+/**
+ * Reinsert \a modifier in modifier list with an offset of \a direction.
+ * \return if position of \a modifier has changed.
+ */
+bool BKE_linestyle_color_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
 {
-	BLI_remlink(lb, modifier);
-	if (direction > 0)
-		BLI_insertlinkbefore(lb, modifier->prev, modifier);
-	else
-		BLI_insertlinkafter(lb, modifier->next, modifier);
+	return BLI_listbase_link_move(&linestyle->color_modifiers, modifier, direction);
 }
-
-void BKE_linestyle_color_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
+bool BKE_linestyle_alpha_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
 {
-	move_modifier(&linestyle->color_modifiers, modifier, direction);
+	return BLI_listbase_link_move(&linestyle->alpha_modifiers, modifier, direction);
 }
-
-void BKE_linestyle_alpha_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
+bool BKE_linestyle_thickness_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
 {
-	move_modifier(&linestyle->alpha_modifiers, modifier, direction);
+	return BLI_listbase_link_move(&linestyle->thickness_modifiers, modifier, direction);
 }
-
-void BKE_linestyle_thickness_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
-{
-	move_modifier(&linestyle->thickness_modifiers, modifier, direction);
-}
-
-void BKE_linestyle_geometry_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
+bool BKE_linestyle_geometry_modifier_move(FreestyleLineStyle *linestyle, LineStyleModifier *modifier, int direction)
 {
-	move_modifier(&linestyle->geometry_modifiers, modifier, direction);
+	return BLI_listbase_link_move(&linestyle->geometry_modifiers, modifier, direction);
 }
 
 void BKE_linestyle_modifier_list_color_ramps(FreestyleLineStyle *linestyle, ListBase *listbase)
diff --git a/source/blender/blenlib/BLI_listbase.h b/source/blender/blenlib/BLI_listbase.h
index 9dfa80006de..96349a7b066 100644
--- a/source/blender/blenlib/BLI_listbase.h
+++ b/source/blender/blenlib/BLI_listbase.h
@@ -69,6 +69,7 @@ void BLI_insertlinkbefore(struct ListBase *listbase, void *vnextlink, void *vnew
 void BLI_insertlinkafter(struct ListBase *listbase, void *vprevlink, void *vnewlink) ATTR_NONNULL(1);
 void BLI_listbase_sort(struct ListBase *listbase, int (*cmp)(const void *, const void *)) ATTR_NONNULL(1, 2);
 void BLI_listbase_sort_r(ListBase *listbase, int (*cmp)(void *, const void *, const void *), void *thunk) ATTR_NONNULL(1, 2);
+bool BLI_listbase_link_move(ListBase *listbase, void *vlink, int step) ATTR_NONNULL();
 void BLI_freelist(struct ListBase *listbase) ATTR_NONNULL(1);
 int  BLI_listbase_count_ex(const struct ListBase *listbase, const int count_max) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(1);
 int  BLI_listbase_count(const struct ListBase *listbase) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(1);
diff --git a/source/blender/blenlib/intern/listbase.c b/source/blender/blenlib/intern/listbase.c
index ebee2c7941c..e72eff57ad9 100644
--- a/source/blender/blenlib/intern/listbase.c
+++ b/source/blender/blenlib/intern/listbase.c
@@ -342,6 +342,44 @@ void BLI_insertlinkbefore(ListBase *listbase, void *vnextlink, void *vnewlink)
 	}
 }
 
+/**
+ * Reinsert \a link relative to its current position but offset by \a step. Doesn't move
+ * item if new position would exceed list (could optionally move to head/tail).
+ *
+ * \param step: Absolute value defines step size, sign defines direction. E.g pass -1
+ *              to move \a link before previous, or 1 to move behind next.
+ * \return If position of \a link has changed.
+ */
+bool BLI_listbase_link_move(ListBase *listbase, void *vlink, int step)
+{
+	Link *link = vlink;
+	Link *hook = link;
+	const bool is_up = step < 0;
+
+	if (step == 0 || vlink == NULL) {
+		return false;
+	}
+	BLI_assert(BLI_findindex(listbase, link) != -1);
+
+	/* find link to insert before/after */
+	for (int i = 0; i < ABS(step); i++) {
+		hook = is_up ? hook->prev : hook->next;
+		if (!hook) {
+			return false;
+		}
+	}
+
+	/* reinsert link */
+	BLI_remlink(listbase, vlink);
+	if (is_up) {
+		BLI_insertlinkbefore(listbase, hook, vlink);
+	}
+	else {
+		BLI_insertlinkafter(listbase, hook, vlink);
+	}
+	return true;
+}
+
 
 /**
  * Removes and disposes of the entire contents of listbase using direct free(3).
diff --git a/source/blender/editors/armature/pose_group.c b/source/blender/editors/armature/pose_group.c
index 85bee023cef..85cff2e4df5 100644
--- a/source/blender/editors/armature/pose_group.c
+++ b/source/blender/editors/armature/pose_group.c
@@ -306,50 +306,31 @@ static int group_move_exec(bContext *C, wmOperator *op)
 
 	/* move bone group */
 	grpIndexA = pose->active_group;
-	if (dir == 1) { /* up */
-		void *prev = grp->prev;
-		
-		if (prev == NULL)
-			return OPERATOR_FINISHED;
-			
-		BLI_remlink(&pose->agroups, grp);
-		BLI_insertlinkbefore(&pose->agroups, prev, grp);
-		
-		grpIndexB = grpIndexA - 1;
-		pose->active_group--;
-	}
-	else { /* down */
-		void *next = grp->next;
-		
-		if (next == NULL)
-			return OPERATOR_FINISHED;
-			
-		BLI_remlink(&pose->agroups, grp);
-		BLI_insertlinkafter(&pose->agroups, next, grp);
-		
-		grpIndexB = grpIndexA + 1;
-		pose->active_group++;
-	}
+	if (BLI_listbase_link_move(&pose->agroups, grp, dir)) {
+		grpIndexB = grpIndexA + dir;
+		pose->active_group += dir;
+		/* fix changed bone group indices in bones (swap grpIndexA with grpIndexB) */
+		for (pchan = ob->pose->chanbase.first; pchan; pchan = pchan->next) {
+			if (pchan->agrp_index == grpIndexB) {
+				pchan->agrp_index = grpIndexA;
+			}
+			else if (pchan->agrp_index == grpIndexA) {
+				pchan->agrp_index = grpIndexB;
+			}
+		}
 
-	/* fix changed bone group indices in bones (swap grpIndexA with grpIndexB) */
-	for (pchan = ob->pose->chanbase.first; pchan; pchan = pchan->next) {
-		if (pchan->agrp_index == grpIndexB)
-			pchan->agrp_index = grpIndexA;
-		else if (pchan->agrp_index == grpIndexA)
-			pchan->agrp_index = grpIndexB;
+		/* notifiers for updates */
+		WM_event_add_notifier(C, NC_OBJECT | ND_POSE, ob);
 	}
 
-	/* notifiers for updates */
-	WM_event_add_notifier(C, NC_OBJECT | ND_POSE, ob);
-
 	return OPERATOR_FINISHED;
 }
 
 void POSE_OT_group_move(wmOperatorType *ot)
 {
 	static EnumPropertyItem group_slot_move[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
diff --git a/source/blender/editors/armature/pose_lib.c b/source/blender/editors/armature/pose_lib.c
index b200aa2401b..4af7f3f8727 100644
--- a/source/blender/editors/armature/pose_lib.c
+++ b/source/blender/editors/armature/pose_lib.c
@@ -766,32 +766,18 @@ static int poselib_move_exec(bContext *C, wmOperator *op)
 	dir = RNA_enum_get(op->ptr, "direction");
 
 	/* move pose */
-	if (dir == 1) { /* up */
-		void *prev = marker->prev;
+	if (BLI_listbase_link_move(&act->markers, marker, dir)) {
+		act->active_marker = marker_index + dir + 1;
 
-		if (prev == NULL)
-			return OPERATOR_CANCELLED;
-
-		BLI_remlink(&act->markers, marker);
-		BLI_insertlinkbefore(&act->markers, prev, marker);
+		/* send notifiers for this - using keyframe editing notifiers, since action
+		 * may be being shown in anim editors as active action
+		 */
+		WM_event_add_notifier(C, NC_ANIMATION | ND_KEYFRAME | NA_EDITED, NULL);
 	}
-	else { /* down */
-		void *next = marker->next;
-
-		if (next == NULL)
-			return OPERATOR_CANCELLED;
-
-		BLI_remlink(&act->markers, marker);
-		BLI_insertlinkafter(&act->markers, next, marker);
+	else {
+		return OPERATOR_CANCELLED;
 	}
 
-	act->active_marker = marker_index - dir + 1;
-
-	/* send notifiers for this - using keyframe editing notifiers, since action
-	 * may be being shown in anim editors as active action
-	 */
-	WM_event_add_notifier(C, NC_ANIMATION | ND_KEYFRAME | NA_EDITED, NULL);
-
 	/* done */
 	return OPERATOR_FINISHED;
 }
@@ -800,8 +786,8 @@ void POSELIB_OT_pose_move(wmOperatorType *ot)
 {
 	PropertyRNA *prop;
 	static EnumPropertyItem pose_lib_pose_move[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
diff --git a/source/blender/editors/gpencil/gpencil_data.c b/source/blender/editors/gpencil/gpencil_data.c
index ce1e397e91c..9a786755484 100644
--- a/source/blender/editors/gpencil/gpencil_data.c
+++ b/source/blender/editors/gpencil/gpencil_data.c
@@ -272,21 +272,11 @@ static int gp_layer_move_exec(bContext *C, wmOperator *op)
 	if (ELEM(NULL, gpd, gpl))
 		return OPERATOR_CANCELLED;
 	
-	/* up or down? */
-	if (direction == GP_LAYER_MOVE_UP) {
-		/* up */
-		BLI_remlink(&gpd->layers, gpl);
-		BLI_insertlinkbefore(&gpd->layers, gpl->prev, gpl);
-	}
-	else {
-		/* down */
-		BLI_remlink(&gpd->layers, gpl);
-		BLI_insertlinkafter(&gpd->layers, gpl->next, gpl);
+	BLI_assert(ELEM(direction, -1, 0, 1)); /* we use value below */
+	if (BLI_listbase_link_move(&gpd->layers, gpl, direction)) {
+		WM_event_add_notifier(C, NC_GPENCIL | ND_DATA | NA_EDITED, NULL);
 	}
 	
-	/* notifiers */
-	WM_event_add_notifier(C, NC_GPENCIL | ND_DATA | NA_EDITED, NULL);
-	
 	return OPERATOR_FINISHED;
 }
 
@@ -782,23 +772,21 @@ static int gp_stroke_arrange_exec(bContext *C, wmOperator *op)
 			for (LinkData *link = selected.first; link; link = link->next) {
 				gps = link->data;
 				BLI_remlink(&gpf->strokes, gps);
-				BLI_insertlinkafter(&gpf->strokes, gpf->strokes.last, gps);
+				BLI_addtail(&gpf->strokes, gps);
 			}
 			break;
 		/* Bring Forward */
 		case GP_STROKE_MOVE_UP:
 			for (LinkData *link = selected.last; link; link = link->prev) {
 				gps = link->data;
-				BLI_remlink(&gpf->strokes, gps);
-				BLI_insertlinkafter(&gpf->strokes, gps->next, gps);
+				BLI_listbase_link_move(&gpf->strokes, gps, 1);
 			}
 			break;
-			/* Send Backward */
+		/* Send Backward */
 		case GP_STROKE_MOVE_DOWN:
 			for (LinkData *link = selected.first; link; link = link->next) {
 				gps = link->data;
-				BLI_remlink(&gpf->strokes, gps);
-				BLI_insertlinkbefore(&gpf->strokes, gps->prev, gps);
+				BLI_listbase_link_move(&gpf->strokes, gps, -1);
 			}
 			break;
 		/* Send to Back */
@@ -806,7 +794,7 @@ static int gp_stroke_arrange_exec(bContext *C, wmOperator *op)
 			for (LinkData *link = selected.last; link; link = link->prev) {
 				gps = link->data;
 				BLI_remlink(&gpf->strokes, gps);
-				BLI_insertlinkbefore(&gpf->strokes, gpf->strokes.first, gps);
+				BLI_addhead(&gpf->strokes, gps);
 			}
 			break;
 		default:
diff --git a/source/blender/editors/object/object_vgroup.c b/source/blender/editors/object/object_vgroup.c
index 3b7f518d36f..bd016b7fcfb 100644
--- a/source/blender/editors/object/object_vgroup.c
+++ b/source/blender/editors/object/object_vgroup.c
@@ -3633,7 +3633,8 @@ static int vgroup_move_exec(bContext *C, wmOperator *op)
 	Object *ob = ED_object_context(C);
 	bDeformGroup *def;
 	char *name_array;
-	int dir = RNA_enum_get(op->ptr, "direction"), ret;
+	int dir = RNA_enum_get(op->ptr, "direction");
+	int ret = OPERATOR_FINISHED;
 
 	def = BLI_findlink(&ob->defbase, ob->actdef - 1);
 	if (!def) {
@@ -3642,36 +3643,25 @@ static int vgroup_move_exec(bContext *C, wmOperator *op)
 
 	name_array = vgroup_init_remap(ob);
 
-	if (dir == 1) { /*up*/
-		void *prev = def->prev;
+	if (BLI_listbase_link_move(&ob->defbase, def, dir)) {
+		ret = vgroup_do_remap(ob, name_array, op);
 
-		BLI_remlink(&ob->defbase, def);
-		BLI_insertlinkbefore(&ob->defbase, prev, def);
-	}
-	else { /*down*/
-		void *next = def->next;
-
-		BLI_remlink(&ob->defbase, def);
-		BLI_insertlinkafter(&ob->defbase, next, def);
+		if (ret != OPERATOR_CANCELLED) {
+			DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
+			WM_event_add_notifier(C, NC_GEOM | ND_VERTEX_GROUP, ob);
+		}
 	}
 
-	ret = vgroup_do_remap(ob, name_array, op);
-
 	if (name_array) MEM_freeN(name_array);
 
-	if (ret != OPERATOR_CANCELLED) {
-		DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
-		WM_event_add_notifier(C, NC_GEOM | ND_VERTEX_GROUP, ob);
-	}
-
 	return ret;
 }
 
 void OBJECT_OT_vertex_group_move(wmOperatorType *ot)
 {
 	static EnumPropertyItem vgroup_slot_move[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
diff --git a/source/blender/editors/render/render_shading.c b/source/blender/editors/render/render_shading.c
index 4796024646c..837573ad175 100644
--- a/source/blender/editors/render/render_shading.c
+++ b/source/blender/editors/render/render_shading.c
@@ -829,14 +829,10 @@ static int freestyle_module_move_exec(bContext *C, wmOperator *op)
 	FreestyleModuleConfig *module = ptr.data;
 	int dir = RNA_enum_get(op->ptr, "direction");
 
-	if (dir == 1) {
-		BKE_freestyle_module_move_up(&srl->freestyleConfig, module);
+	if (BKE_freestyle_module_move(&srl->freestyleConfig, module, dir)) {
+		DAG_id_tag_update(&scene->id, 0);
+		WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, scene);
 	}
-	else {
-		BKE_freestyle_module_move_down(&srl->freestyleConfig, module);
-	}
-	DAG_id_tag_update(&scene->id, 0);
-	WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, scene);
 
 	return OPERATOR_FINISHED;
 }
@@ -844,8 +840,8 @@ static int freestyle_module_move_exec(bContext *C, wmOperator *op)
 void SCENE_OT_freestyle_module_move(wmOperatorType *ot)
 {
 	static EnumPropertyItem direction_items[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
@@ -993,14 +989,10 @@ static int freestyle_lineset_move_exec(bContext *C, wmOperator *op)
 	SceneRenderLayer *srl = BLI_findlink(&scene->r.layers, scene->r.actlay);
 	int dir = RNA_enum_get(op->ptr, "direction");
 
-	if (dir == 1) {
-		FRS_move_active_lineset_up(&srl->freestyleConfig);
-	}
-	else {
-		FRS_move_active_lineset_down(&srl->freestyleConfig);
+	if (FRS_move_active_lineset(&srl->freestyleConfig, dir)) {
+		DAG_id_tag_update(&scene->id, 0);
+		WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, scene);
 	}
-	DAG_id_tag_update(&scene->id, 0);
-	WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, scene);
 
 	return OPERATOR_FINISHED;
 }
@@ -1008,8 +1000,8 @@ static int freestyle_lineset_move_exec(bContext *C, wmOperator *op)
 void SCENE_OT_freestyle_lineset_move(wmOperatorType *ot)
 {
 	static EnumPropertyItem direction_items[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
@@ -1350,6 +1342,7 @@ static int freestyle_modifier_move_exec(bContext *C, wmOperator *op)
 	PointerRNA ptr = CTX_data_pointer_get_type(C, "modifier", &RNA_LineStyleModifier);
 	LineStyleModifier *modifier = ptr.data;
 	int dir = RNA_enum_get(op->ptr, "direction");
+	bool changed = false;
 
 	if (!freestyle_linestyle_check_report(lineset, op->reports)) {
 		return OPERATOR_CANCELLED;
@@ -1357,23 +1350,26 @@ static int freestyle_modifier_move_exec(bContext *C, wmOperator *op)
 
 	switch (freestyle_get_modifier_type(&ptr)) {
 		case LS_MODIFIER_TYPE_COLOR:
-			BKE_linestyle_color_modifier_move(lineset->linestyle, modifier, dir);
+			changed = BKE_linestyle_color_modifier_move(lineset->linestyle, modifier, dir);
 			break;
 		case LS_MODIFIER_TYPE_ALPHA:
-			BKE_linestyle_alpha_modifier_move(lineset->linestyle, modifier, dir);
+			changed = BKE_linestyle_alpha_modifier_move(lineset->linestyle, modifier, dir);
 			break;
 		case LS_MODIFIER_TYPE_THICKNESS:
-			BKE_linestyle_thickness_modifier_move(lineset->linestyle, modifier, dir);
+			changed = BKE_linestyle_thickness_modifier_move(lineset->linestyle, modifier, dir);
 			break;
 		case LS_MODIFIER_TYPE_GEOMETRY:
-			BKE_linestyle_geometry_modifier_move(lineset->linestyle, modifier, dir);
+			changed = BKE_linestyle_geometry_modifier_move(lineset->linestyle, modifier, dir);
 			break;
 		default:
 			BKE_report(op->reports, RPT_ERROR, "The object the data pointer refers to is not a valid modifier");
 			return OPERATOR_CANCELLED;
 	}
-	DAG_id_tag_update(&lineset->linestyle->id, 0);
-	WM_event_add_notifier(C, NC_LINESTYLE, lineset->linestyle);
+
+	if (changed) {
+		DAG_id_tag_update(&lineset->linestyle->id, 0);
+		WM_event_add_notifier(C, NC_LINESTYLE, lineset->linestyle);
+	}
 
 	return OPERATOR_FINISHED;
 }
@@ -1381,8 +1377,8 @@ static int freestyle_modifier_move_exec(bContext *C, wmOperator *op)
 void SCENE_OT_freestyle_modifier_move(wmOperatorType *ot)
 {
 	static EnumPropertyItem direction_items[] = {
-		{1, "UP", 0, "Up", ""},
-		{-1, "DOWN", 0, "Down", ""},
+		{-1, "UP", 0, "Up", ""},
+		{1, "DOWN", 0, "Down", ""},
 		{0, NULL, 0, NULL, NULL}
 	};
 
diff --git a/source/blender/freestyle/FRS_freestyle.h b/source/blender/freestyle/FRS_freestyle.h
index 039a75a2f0f..a6382010ca7 100644
--- a/source/blender/freestyle/FRS_freestyle.h
+++ b/source/blender/freestyle/FRS_freestyle.h
@@ -63,8 +63,7 @@ void FRS_exit(void);
 void FRS_copy_active_lineset(struct FreestyleConfig *config);
 void FRS_paste_active_lineset(struct FreestyleConfig *config);
 void FRS_delete_active_lineset(struct FreestyleConfig *config);
-void FRS_move_active_lineset_up(struct FreestyleConfig *config);
-void FRS_move_active_lineset_down(struct FreestyleConfig *config);
+bool FRS_move_active_lineset(struct FreestyleConfig *config, int direction);
 
 /* Testing */
 struct Material *FRS_create_stroke_material(struct Main *bmain, struct FreestyleLineStyle *linestyle);
diff --git a/source/blender/freestyle/intern/blender_interface/FRS_freestyle.cpp b/source/blender/freestyle/intern/blender_interface/FRS_freestyle.cpp
index 4d8c6a66d42..2af4447e4dc 100644
--- a/source/blender/freestyle/intern/blender_interface/FRS_freestyle.cpp
+++ b/source/blender/freestyle/intern/blender_interface/FRS_freestyle.cpp
@@ -730,24 +730,14 @@ void FRS_delete_active_lineset(FreestyleConfig *config)
 	}
 }
 
-void FRS_move_active_lineset_up(FreestyleConfig *config)
-{
-	FreestyleLineSet *lineset = BKE_freestyle_lineset_get_active(config);
-
-	if (lineset) {
-		BLI_remlink(&config->linesets, lineset);
-		BLI_insertlinkbefore(&config->linesets, lineset->prev, lineset);
-	}
-}
-
-void FRS_move_active_lineset_down(FreestyleConfig *config)
+/**
+ * Reinsert the active lineset at an offset \a direction from current position.
+ * \return if position of active lineset has changed.
+ */
+bool FRS_move_active_lineset(FreestyleConfig *config, int direction)
 {
 	FreestyleLineSet *lineset = BKE_freestyle_lineset_get_active(config);
-
-	if (lineset) {
-		BLI_remlink(&config->linesets, lineset);
-		BLI_insertlinkafter(&config->linesets, lineset->next, lineset);
-	}
+	return (lineset != NULL) && BLI_listbase_link_move(&config->linesets, lineset, direction);
 }
 
 // Testing
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index 820465ee7d1..2893fabd145 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -916,7 +916,7 @@ int RNA_property_enum_get(PointerRNA *ptr, PropertyRNA *prop);
 void RNA_property_enum_set(PointerRNA *ptr, PropertyRNA *prop, int value);
 int RNA_property_enum_get_default(PointerRNA *ptr, PropertyRNA *prop);
 void *RNA_property_enum_py_data_get(PropertyRNA *prop);
-int RNA_property_enum_step(const struct bContext *C, PointerRNA *ptr, PropertyRNA *prop, int from_value, int direction);
+int RNA_property_enum_step(const struct bContext *C, PointerRNA *ptr, PropertyRNA *prop, int from_value, int step);
 
 PointerRNA RNA_property_pointer_get(PointerRNA *ptr, PropertyRNA *prop);
 void RNA_property_pointer_set(PointerRNA *ptr, PropertyRNA *prop, PointerRNA ptr_value);