Fix T38245: render slot getting lost when switching slots while compositing.

5 files changed, 16 insertions, 11 deletions

diff --git a/source/blender/blenkernel/BKE_image.h b/source/blender/blenkernel/BKE_image.h
index ea63161e008..ff0b5a1d4bf 100644
--- a/source/blender/blenkernel/BKE_image.h
+++ b/source/blender/blenkernel/BKE_image.h
@@ -221,7 +221,7 @@ void BKE_image_release_renderresult(struct Scene *scene, struct Image *ima);
 bool BKE_image_is_openexr(struct Image *ima);
 
 /* for multiple slot render, call this before render */
-void BKE_image_backup_render(struct Scene *scene, struct Image *ima);
+void BKE_image_backup_render(struct Scene *scene, struct Image *ima, bool free_current_slot);
 
 /* for singlelayer openexr saving */
 bool BKE_image_save_openexr_multiview(struct Image *ima, struct ImBuf *ibuf, const char *filepath, const int flags);
diff --git a/source/blender/blenkernel/intern/image.c b/source/blender/blenkernel/intern/image.c
index f4fce5c0019..6ff30134210 100644
--- a/source/blender/blenkernel/intern/image.c
+++ b/source/blender/blenkernel/intern/image.c
@@ -2923,7 +2923,7 @@ bool BKE_image_is_openexr(struct Image *ima)
 	return false;
 }
 
-void BKE_image_backup_render(Scene *scene, Image *ima)
+void BKE_image_backup_render(Scene *scene, Image *ima, bool free_current_slot)
 {
 	/* called right before rendering, ima->renders contains render
 	 * result pointers for everything but the current render */
@@ -2931,13 +2931,18 @@ void BKE_image_backup_render(Scene *scene, Image *ima)
 	int slot = ima->render_slot, last = ima->last_render_slot;
 
 	if (slot != last) {
-		if (ima->renders[slot]) {
-			RE_FreeRenderResult(ima->renders[slot]);
-			ima->renders[slot] = NULL;
-		}
-
 		ima->renders[last] = NULL;
 		RE_SwapResult(re, &ima->renders[last]);
+
+		if (ima->renders[slot]) {
+			if (free_current_slot) {
+				RE_FreeRenderResult(ima->renders[slot]);
+				ima->renders[slot] = NULL;
+			}
+			else {
+				RE_SwapResult(re, &ima->renders[slot]);
+			}
+		}
 	}
 
 	ima->last_render_slot = slot;
diff --git a/source/blender/editors/render/render_internal.c b/source/blender/editors/render/render_internal.c
index f44374b1d7b..a7038ac53cc 100644
--- a/source/blender/editors/render/render_internal.c
+++ b/source/blender/editors/render/render_internal.c
@@ -311,7 +311,7 @@ static int screen_render_exec(bContext *C, wmOperator *op)
 
 	ima = BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result");
 	BKE_image_signal(ima, NULL, IMA_SIGNAL_FREE);
-	BKE_image_backup_render(scene, ima);
+	BKE_image_backup_render(scene, ima, true);
 
 	/* cleanup sequencer caches before starting user triggered render.
 	 * otherwise, invalidated cache entries can make their way into
@@ -956,7 +956,7 @@ static int screen_render_invoke(bContext *C, wmOperator *op, const wmEvent *even
 	/* get a render result image, and make sure it is empty */
 	ima = BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result");
 	BKE_image_signal(ima, NULL, IMA_SIGNAL_FREE);
-	BKE_image_backup_render(rj->scene, ima);
+	BKE_image_backup_render(rj->scene, ima, true);
 	rj->image = ima;
 
 	/* setup new render */
diff --git a/source/blender/editors/render/render_opengl.c b/source/blender/editors/render/render_opengl.c
index 2e9ccc520d9..f94f3cdf758 100644
--- a/source/blender/editors/render/render_opengl.c
+++ b/source/blender/editors/render/render_opengl.c
@@ -559,7 +559,7 @@ static bool screen_opengl_render_init(bContext *C, wmOperator *op)
 	/* create image and image user */
 	oglrender->ima = BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result");
 	BKE_image_signal(oglrender->ima, NULL, IMA_SIGNAL_FREE);
-	BKE_image_backup_render(oglrender->scene, oglrender->ima);
+	BKE_image_backup_render(oglrender->scene, oglrender->ima, true);
 
 	oglrender->iuser.scene = scene;
 	oglrender->iuser.ok = 1;
diff --git a/source/blender/editors/space_node/node_edit.c b/source/blender/editors/space_node/node_edit.c
index 413cdc208dd..a312888fc44 100644
--- a/source/blender/editors/space_node/node_edit.c
+++ b/source/blender/editors/space_node/node_edit.c
@@ -277,7 +277,7 @@ void ED_node_composite_job(const bContext *C, struct bNodeTree *nodetree, Scene
 	G.is_break = false;
 #endif
 
-	BKE_image_backup_render(scene, BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result"));
+	BKE_image_backup_render(scene, BKE_image_verify_viewer(IMA_TYPE_R_RESULT, "Render Result"), false);
 
 	wm_job = WM_jobs_get(CTX_wm_manager(C), CTX_wm_window(C), scene_owner, "Compositing",
 	                     WM_JOB_EXCL_RENDER | WM_JOB_PROGRESS, WM_JOB_TYPE_COMPOSITE);