3 files changed, 48 insertions, 8 deletions

diff --git a/source/blender/editors/space_image/image_edit.c b/source/blender/editors/space_image/image_edit.c
index 9a6f7431d17..c8edccb0472 100644
--- a/source/blender/editors/space_image/image_edit.c
+++ b/source/blender/editors/space_image/image_edit.c
@@ -57,9 +57,13 @@ Image *ED_space_image(SpaceImage *sima)
 	return sima->image;
 }
 
-/* called to assign images to UV faces */
-void ED_space_image_set(Main *bmain, SpaceImage *sima, Object *obedit, Image *ima)
+void ED_space_image_set(Main *bmain, SpaceImage *sima, Object *obedit, Image *ima, bool automatic)
 {
+	/* Automatically pin image when manually assigned, otherwise it follows object. */
+	if (!automatic && sima->image != ima && sima->mode == SI_MODE_UV) {
+		sima->pin = true;
+	}
+
 	/* change the space ima after because uvedit_face_visible_test uses the space ima
 	 * to check if the face is displayed in UV-localview */
 	sima->image = ima;
@@ -81,6 +85,38 @@ void ED_space_image_set(Main *bmain, SpaceImage *sima, Object *obedit, Image *im
 	WM_main_add_notifier(NC_SPACE | ND_SPACE_IMAGE, NULL);
 }
 
+void ED_space_image_auto_set(const bContext *C, SpaceImage *sima)
+{
+	if (sima->mode != SI_MODE_UV || sima->pin) {
+		return;
+	}
+
+	/* Track image assigned to active face in edit mode. */
+	Object *ob = CTX_data_active_object(C);
+	if (!(ob && (ob->mode & OB_MODE_EDIT) && ED_space_image_show_uvedit(sima, ob))) {
+		return;
+	}
+
+	BMEditMesh *em = BKE_editmesh_from_object(ob);
+	BMesh *bm = em->bm;
+	BMFace *efa = BM_mesh_active_face_get(bm, true, false);
+	if (efa == NULL) {
+		return;
+	}
+
+	Image *ima = NULL;
+	ED_object_get_active_image(ob, efa->mat_nr + 1, &ima, NULL, NULL, NULL);
+
+	if (ima != sima->image) {
+		sima->image = ima;
+
+		if (sima->image) {
+			Main *bmain = CTX_data_main(C);
+			BKE_image_signal(bmain, sima->image, &sima->iuser, IMA_SIGNAL_USER_NEW_IMAGE);
+		}
+	}
+}
+
 Mask *ED_space_image_get_mask(SpaceImage *sima)
 {
 	return sima->mask_info.mask;
diff --git a/source/blender/editors/space_image/image_ops.c b/source/blender/editors/space_image/image_ops.c
index 064a4d2ce11..bba336ca2e0 100644
--- a/source/blender/editors/space_image/image_ops.c
+++ b/source/blender/editors/space_image/image_ops.c
@@ -1300,7 +1300,7 @@ static int image_open_exec(bContext *C, wmOperator *op)
 	}
 	else if (sa && sa->spacetype == SPACE_IMAGE) {
 		SpaceImage *sima = sa->spacedata.first;
-		ED_space_image_set(bmain, sima, obedit, ima);
+		ED_space_image_set(bmain, sima, obedit, ima, false);
 		iuser = &sima->iuser;
 	}
 	else {
@@ -2461,7 +2461,7 @@ static int image_new_exec(bContext *C, wmOperator *op)
 		RNA_property_update(C, &data->pprop.ptr, data->pprop.prop);
 	}
 	else if (sima) {
-		ED_space_image_set(bmain, sima, obedit, ima);
+		ED_space_image_set(bmain, sima, obedit, ima, false);
 	}
 
 	BKE_image_signal(bmain, ima, (sima) ? &sima->iuser : NULL, IMA_SIGNAL_USER_NEW_IMAGE);
@@ -3800,7 +3800,7 @@ static int image_read_viewlayers_exec(bContext *C, wmOperator *UNUSED(op))
 
 	ima = BKE_image_verify_viewer(bmain, IMA_TYPE_R_RESULT, "Render Result");
 	if (sima->image == NULL) {
-		ED_space_image_set(bmain, sima, NULL, ima);
+		ED_space_image_set(bmain, sima, NULL, ima, false);
 	}
 
 	RE_ReadRenderResult(scene, scene);
diff --git a/source/blender/editors/space_image/space_image.c b/source/blender/editors/space_image/space_image.c
index 6ae4eb9767b..7aa3ea57956 100644
--- a/source/blender/editors/space_image/space_image.c
+++ b/source/blender/editors/space_image/space_image.c
@@ -100,15 +100,19 @@ static void image_scopes_tag_refresh(ScrArea *sa)
 
 static void image_user_refresh_scene(const bContext *C, SpaceImage *sima)
 {
+	/* Update scene image user for acquiring render results. */
+	sima->iuser.scene = CTX_data_scene(C);
+
 	if (sima->image && sima->image->type == IMA_TYPE_R_RESULT) {
-		/* for render result, try to use the currently rendering scene */
+		/* While rendering, prefer scene that is being rendered. */
 		Scene *render_scene = ED_render_job_get_current_scene(C);
 		if (render_scene) {
 			sima->iuser.scene = render_scene;
-			return;
 		}
 	}
-	sima->iuser.scene = CTX_data_scene(C);
+
+	/* Auto switch image to show in UV editor when selection changes. */
+	ED_space_image_auto_set(C, sima);
 }
 
 /* ******************** manage regions ********************* */