Images: Solve broken forward compatibility with packed images

Use first packed image as legacy image->packedfile, so saving .blend file with
latest builds makes it so packed images are not lost when opening with previous
releases.

This will only work reliably if mutliview is not used, otherwise it'll be only
first view in the .blend file, which is rather expected since previous releases
are not aware of views.

3 files changed, 11 insertions, 6 deletions

diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index c736e54c4e9..a22e882937c 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -1536,9 +1536,6 @@ void blo_make_packed_pointer_map(FileData *fd, Main *oldmain)
 	
 	for (ima = oldmain->image.first; ima; ima = ima->id.next) {
 		ImagePackedFile *imapf;
-		if (ima->packedfile)
-			insert_packedmap(fd, ima->packedfile);
-
 		for (imapf = ima->packedfiles.first; imapf; imapf = imapf->next)
 			if (imapf->packedfile)
 				insert_packedmap(fd, imapf->packedfile);
@@ -1577,8 +1574,6 @@ void blo_end_packed_pointer_map(FileData *fd, Main *oldmain)
 	
 	for (ima = oldmain->image.first; ima; ima = ima->id.next) {
 		ImagePackedFile *imapf;
-		ima->packedfile = newpackedadr(fd, ima->packedfile);
-
 		for (imapf = ima->packedfiles.first; imapf; imapf = imapf->next)
 			imapf->packedfile = newpackedadr(fd, imapf->packedfile);
 	}
@@ -3437,6 +3432,7 @@ static void direct_link_image(FileData *fd, Image *ima)
 	link_list(fd, &(ima->views));
 	link_list(fd, &(ima->packedfiles));
 
+	ima->packedfile = NULL;
 	for (imapf = ima->packedfiles.first; imapf; imapf = imapf->next) {
 		imapf->packedfile = direct_link_packedfile(fd, imapf->packedfile);
 	}
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index 43f9fcce76d..fc464714edc 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -2161,6 +2161,13 @@ static void write_images(WriteData *wd, ListBase *idbase)
 	ima= idbase->first;
 	while (ima) {
 		if (ima->id.us>0 || wd->current) {
+			/* Some trickery to keep forward compatibility of packed images. */
+			BLI_assert(ima->packedfile == NULL);
+			if (ima->packedfiles.first != NULL) {
+				imapf = ima->packedfiles.first;
+				ima->packedfile = imapf->packedfile;
+			}
+
 			/* write LibData */
 			writestruct(wd, ID_IM, "Image", 1, ima);
 			if (ima->id.properties) IDP_WriteProperty(ima->id.properties, wd);
@@ -2179,6 +2186,8 @@ static void write_images(WriteData *wd, ListBase *idbase)
 			for (iv = ima->views.first; iv; iv = iv->next)
 				writestruct(wd, DATA, "ImageView", 1, iv);
 			writestruct(wd, DATA, "Stereo3dFormat", 1, ima->stereo3d_format);
+
+			ima->packedfile = NULL;
 		}
 		ima= ima->id.next;
 	}
diff --git a/source/blender/makesdna/DNA_image_types.h b/source/blender/makesdna/DNA_image_types.h
index da5eee07e52..0e2a41a0aeb 100644
--- a/source/blender/makesdna/DNA_image_types.h
+++ b/source/blender/makesdna/DNA_image_types.h
@@ -115,7 +115,7 @@ typedef struct Image {
 	unsigned int bindcode;	/* only for current image... */
 	unsigned int *repbind;	/* for repeat of parts of images */
 	
-	struct PackedFile *packedfile; /* deprecated */
+	struct PackedFile *packedfile DNA_DEPRECATED; /* deprecated */
 	struct ListBase packedfiles;
 	struct PreviewImage *preview;