Nicer handling of undefined node, tree and socket types.

When nodes are loaded from a .blend file they can potentially have undefined types. This can happen if a type has been deprecated and removed, or if node types were defined in a python script that has not been loaded correctly. Previously all such nodes would automatically be removed from a node tree, assuming that their types were deprecated and no longer in use (more commonly caused by loading new nodes in an older Blender version). Due to the possibility of dynamic registration it is no longer feasible to simply delete such nodes.

Display and handling of node trees was simply disabled before this patch, so that a node tree where any node or socket type was undefined would not be displayed at all. To give more information and avoid problems caused by necessary checks for the typeinfo pointer, there is now a 'Undefined' fallback type for trees, nodes and sockets. These types are used as placeholders in case the real type is not registered and can provide useful visual feedback on undefined nodes.

7 files changed, 63 insertions, 12 deletions

diff --git a/source/blender/editors/screen/screen_ops.c b/source/blender/editors/screen/screen_ops.c
index 8b69e6e831d..d5d5add215c 100644
--- a/source/blender/editors/screen/screen_ops.c
+++ b/source/blender/editors/screen/screen_ops.c
@@ -254,7 +254,7 @@ int ED_operator_node_active(bContext *C)
 {
 	SpaceNode *snode = CTX_wm_space_node(C);
 	
-	if (snode && ntreeIsValid(snode->edittree))
+	if (snode && snode->edittree)
 		return 1;
 	
 	return 0;
diff --git a/source/blender/editors/space_buttons/buttons_texture.c b/source/blender/editors/space_buttons/buttons_texture.c
index bb1310d486a..b108f9fa4b5 100644
--- a/source/blender/editors/space_buttons/buttons_texture.c
+++ b/source/blender/editors/space_buttons/buttons_texture.c
@@ -113,15 +113,15 @@ static void buttons_texture_users_find_nodetree(ListBase *users, ID *id,
 {
 	bNode *node;
 
-	if (ntreeIsValid(ntree)) {
+	if (ntree) {
 		for (node = ntree->nodes.first; node; node = node->next) {
 			if (node->typeinfo->nclass == NODE_CLASS_TEXTURE) {
 				PointerRNA ptr;
 				/* PropertyRNA *prop; */ /* UNUSED */
-
+				
 				RNA_pointer_create(&ntree->id, &RNA_Node, node, &ptr);
 				/* prop = RNA_struct_find_property(&ptr, "texture"); */ /* UNUSED */
-
+				
 				buttons_texture_user_node_add(users, id, ntree, node,
 				                              category, RNA_struct_ui_icon(ptr.type), node->name);
 			}
diff --git a/source/blender/editors/space_node/drawnode.c b/source/blender/editors/space_node/drawnode.c
index fa4b0595061..06528727e72 100644
--- a/source/blender/editors/space_node/drawnode.c
+++ b/source/blender/editors/space_node/drawnode.c
@@ -2708,8 +2708,57 @@ static void node_template_properties_update(bNodeType *ntype)
 	}
 }
 
+static void node_socket_undefined_draw(bContext *UNUSED(C), uiLayout *layout, PointerRNA *UNUSED(ptr), PointerRNA *UNUSED(node_ptr))
+{
+	uiItemL(layout, "Undefined Socket Type", ICON_ERROR);
+}
+
+static void node_socket_undefined_draw_color(bContext *UNUSED(C), PointerRNA *UNUSED(ptr), PointerRNA *UNUSED(node_ptr), float *r_color)
+{
+	r_color[0] = 1.0f;
+	r_color[1] = 0.0f;
+	r_color[2] = 0.0f;
+	r_color[3] = 1.0f;
+}
+
+static void node_socket_undefined_interface_draw(bContext *UNUSED(C), uiLayout *layout, PointerRNA *UNUSED(ptr))
+{
+	uiItemL(layout, "Undefined Socket Type", ICON_ERROR);
+}
+
+static void node_socket_undefined_interface_draw_color(bContext *UNUSED(C), PointerRNA *UNUSED(ptr), float *r_color)
+{
+	r_color[0] = 1.0f;
+	r_color[1] = 0.0f;
+	r_color[2] = 0.0f;
+	r_color[3] = 1.0f;
+}
+
 void ED_node_init_butfuncs(void)
 {
+	/* Fallback types for undefined tree, nodes, sockets
+	 * Defined in blenkernel, but not registered in type hashes.
+	 */
+	/*extern bNodeTreeType NodeTreeTypeUndefined;*/
+	extern bNodeType NodeTypeUndefined;
+	extern bNodeSocketType NodeSocketTypeUndefined;
+	
+	/* default ui functions */
+	NodeTypeUndefined.drawfunc = node_draw_default;
+	NodeTypeUndefined.drawupdatefunc = node_update_default;
+	NodeTypeUndefined.select_area_func = node_select_area_default;
+	NodeTypeUndefined.tweak_area_func = node_tweak_area_default;
+	NodeTypeUndefined.uifunc = NULL;
+	NodeTypeUndefined.uifuncbut = NULL;
+	NodeTypeUndefined.drawinputfunc = node_draw_input_default;
+	NodeTypeUndefined.drawoutputfunc = node_draw_output_default;
+	NodeTypeUndefined.resize_area_func = node_resize_area_default;
+	
+	NodeSocketTypeUndefined.draw = node_socket_undefined_draw;
+	NodeSocketTypeUndefined.draw_color = node_socket_undefined_draw_color;
+	NodeSocketTypeUndefined.interface_draw = node_socket_undefined_interface_draw;
+	NodeSocketTypeUndefined.interface_draw_color = node_socket_undefined_interface_draw_color;
+	
 	/* node type ui functions */
 	NODE_TYPES_BEGIN(ntype)
 		/* default ui functions */
diff --git a/source/blender/editors/space_node/node_buttons.c b/source/blender/editors/space_node/node_buttons.c
index 688377c7f3b..efdb7c0d85d 100644
--- a/source/blender/editors/space_node/node_buttons.c
+++ b/source/blender/editors/space_node/node_buttons.c
@@ -62,7 +62,7 @@ static int active_nodetree_poll(const bContext *C, PanelType *UNUSED(pt))
 {
 	SpaceNode *snode = CTX_wm_space_node(C);
 	
-	return (snode && ntreeIsValid(snode->nodetree));
+	return (snode && snode->nodetree);
 }
 
 /* poll callback for active node */
@@ -70,7 +70,7 @@ static int active_node_poll(const bContext *C, PanelType *UNUSED(pt))
 {
 	SpaceNode *snode = CTX_wm_space_node(C);
 	
-	return (snode && ntreeIsValid(snode->edittree) && nodeGetActive(snode->edittree));
+	return (snode && snode->edittree && nodeGetActive(snode->edittree));
 }
 
 /* active node */
diff --git a/source/blender/editors/space_node/node_draw.c b/source/blender/editors/space_node/node_draw.c
index 0636dee9bc5..6c53b6e8c56 100644
--- a/source/blender/editors/space_node/node_draw.c
+++ b/source/blender/editors/space_node/node_draw.c
@@ -148,7 +148,7 @@ static int has_nodetree(bNodeTree *ntree, bNodeTree *lookup)
 
 void ED_node_tag_update_nodetree(Main *bmain, bNodeTree *ntree)
 {
-	if (!ntreeIsValid(ntree))
+	if (!ntree)
 		return;
 	
 	/* look through all datablocks, to support groups */
@@ -861,7 +861,9 @@ static void node_draw_basis(const bContext *C, ARegion *ar, SpaceNode *snode, bN
 	         NULL, 0, 0, 0, 0, "");
 
 	/* body */
-	if (node->flag & NODE_CUSTOM_COLOR)
+	if (!nodeIsRegistered(node))
+		UI_ThemeColor4(TH_REDALERT);	/* use warning color to indicate undefined types */
+	else if (node->flag & NODE_CUSTOM_COLOR)
 		glColor3fv(node->color);
 	else
 		UI_ThemeColor4(TH_NODE);
@@ -1057,7 +1059,7 @@ void node_set_cursor(wmWindow *win, SpaceNode *snode)
 	bNodeSocket *sock;
 	int cursor = CURSOR_STD;
 	
-	if (ntreeIsValid(ntree)) {
+	if (ntree) {
 		if (node_find_indicated_socket(snode, &node, &sock, SOCK_IN | SOCK_OUT)) {
 			/* pass */
 		}
@@ -1271,7 +1273,7 @@ void drawnodespace(const bContext *C, ARegion *ar)
 		for (curdepth = depth; curdepth >= 0; path = path->next, --curdepth) {
 			ntree = path->nodetree;
 			
-			if (ntreeIsValid(ntree)) {
+			if (ntree) {
 				snode_setup_v2d(snode, ar, ntree->view_center[0], ntree->view_center[1]);
 				
 				if (curdepth == 0) {
diff --git a/source/blender/editors/space_node/node_templates.c b/source/blender/editors/space_node/node_templates.c
index 0bc2fba0d0b..527defb1f07 100644
--- a/source/blender/editors/space_node/node_templates.c
+++ b/source/blender/editors/space_node/node_templates.c
@@ -606,7 +606,7 @@ void uiTemplateNodeView(uiLayout *layout, bContext *C, bNodeTree *ntree, bNode *
 {
 	bNode *tnode;
 
-	if (!ntreeIsValid(ntree))
+	if (!ntree)
 		return;
 
 	/* clear for cycle check */
diff --git a/source/blender/editors/space_node/space_node.c b/source/blender/editors/space_node/space_node.c
index 2d5207e69db..2075cc055e1 100644
--- a/source/blender/editors/space_node/space_node.c
+++ b/source/blender/editors/space_node/space_node.c
@@ -479,7 +479,7 @@ static void node_area_refresh(const struct bContext *C, ScrArea *sa)
 	
 	snode_set_context(C);
 
-	if (ntreeIsValid(snode->nodetree)) {
+	if (snode->nodetree) {
 		if (snode->nodetree->type == NTREE_SHADER) {
 			if (GS(snode->id->name) == ID_MA) {
 				Material *ma = (Material *)snode->id;