UI: support cycling for image space menus

also remove arrow buttons.

1 files changed, 28 insertions, 0 deletions

diff --git a/source/blender/editors/space_image/image_edit.c b/source/blender/editors/space_image/image_edit.c
index 38c9604d14b..35834857423 100644
--- a/source/blender/editors/space_image/image_edit.c
+++ b/source/blender/editors/space_image/image_edit.c
@@ -291,6 +291,34 @@ void ED_image_point_pos__reverse(SpaceImage *sima, ARegion *ar, const float co[2
 	r_co[1] = (co[1] * height * zoomy) + (float)sy;
 }
 
+/**
+ * This is more a user-level functionality, for going to next/prev used slot,
+ * Stepping onto the last unused slot too.
+ */
+bool ED_image_slot_cycle(struct Image *image, int direction)
+{
+	const int cur = image->render_slot;
+	int i, slot;
+
+	BLI_assert(ELEM(direction, -1, 1));
+
+	for (i = 1; i < IMA_MAX_RENDER_SLOT; i++) {
+		slot = (cur + ((direction == -1) ? -i : i)) % IMA_MAX_RENDER_SLOT;
+		if (slot < 0) slot += IMA_MAX_RENDER_SLOT;
+
+		if (image->renders[slot] || slot == image->last_render_slot) {
+			image->render_slot = slot;
+			break;
+		}
+	}
+
+	if (i == IMA_MAX_RENDER_SLOT) {
+		image->render_slot = ((cur == 1) ? 0 : 1);
+	}
+
+	return (cur != image->render_slot);
+}
+
 void ED_space_image_scopes_update(const struct bContext *C, struct SpaceImage *sima, struct ImBuf *ibuf, bool use_view_settings)
 {
 	Scene *scene = CTX_data_scene(C);