Fix #36628, Muting bump node alters material visibility.

The internal connections used for muted nodes are a "best guess" only. The algorithm would connect linked input/output sockets first, regardless of sensible connections. Replaced this by a more strict
connection method now which only uses matching types, so that Normal outputs won't get input from values, etc.

This is still far from perfect though. Eventually it may be necessary to implement dedicated methods for certain types of nodes to respect different semantics - using the plain socket type is just not
enough information. Also the value used for connections from muted nodes with no matching input will currently be the hidden(!) socket input values, this can lead to unexpected results. Needs further
thought ...

1 files changed, 36 insertions, 68 deletions

diff --git a/source/blender/nodes/intern/node_util.c b/source/blender/nodes/intern/node_util.c
index f9a450174a3..e77f0a08331 100644
--- a/source/blender/nodes/intern/node_util.c
+++ b/source/blender/nodes/intern/node_util.c
@@ -112,86 +112,54 @@ const char *node_filter_label(bNode *node)
 
 void node_update_internal_links_default(bNodeTree *ntree, bNode *node)
 {
-	bNodeSocket *fromsock_first = NULL, *tosock_first = NULL;   /* used for fallback link if no other reconnections are found */
-	int datatype;
-	int num_links_in = 0, num_links_out = 0, num_reconnect = 0;
+	bNodeLink *link;
+	bNodeSocket *output, *input, *selected;
 
-	/* Security check! */
+	/* sanity check */
 	if (!ntree)
 		return;
 
-	for (datatype = 0; datatype < NUM_SOCKET_TYPES; ++datatype) {
-		bNodeSocket *fromsock, *tosock;
-		int fromindex, toindex;
-		bNodeLink *link;
-		
-		/* Connect the first input of each type with outputs of the same type. */
+	/* use link pointer as a tag for handled sockets (for outputs is unused anyway) */
+	for (output = node->outputs.first; output; output = output->next)
+		output->link = NULL;
+	
+	for (link = ntree->links.first; link; link = link->next) {
+		output = link->fromsock;
+		if (link->fromnode != node || output->link)
+			continue;
+		output->link = link; /* not really used, just for tagging handled sockets */
 		
-		fromindex = INT_MAX;
-		fromsock = NULL;
-		for (link = ntree->links.first; link; link = link->next) {
-			if (nodeLinkIsHidden(link))
-				continue;
-			if (link->tonode == node && link->tosock->type == datatype) {
-				int index = BLI_findindex(&node->inputs, link->tosock);
-				if (index < fromindex) {
-					fromindex = index;
-					fromsock = link->tosock;
+		/* look for suitable input */
+		selected = NULL;
+		for (input = node->inputs.first; input; input = input->next) {
+			/* only use if same type */
+			if (input->type == output->type) {
+				if (!selected) {
+					selected = input;
 				}
-			}
-		}
-		if (fromsock) {
-			++num_links_in;
-			if (!fromsock_first)
-				fromsock_first = fromsock;
-		}
-		
-		toindex = INT_MAX;
-		tosock = NULL;
-		for (link = ntree->links.first; link; link = link->next) {
-			if (nodeLinkIsHidden(link))
-				continue;
-			if (link->fromnode == node && link->fromsock->type == datatype) {
-				int index = BLI_findindex(&node->outputs, link->fromsock);
-				if (index < toindex) {
-					toindex = index;
-					tosock = link->fromsock;
+				else {
+					/* linked inputs preferred */
+					if (input->link && !selected->link)
+						selected = input;
 				}
 			}
 		}
-		if (tosock) {
-			++num_links_out;
-			if (!tosock_first)
-				tosock_first = tosock;
-			
-			if (fromsock) {
-				bNodeLink *ilink = MEM_callocN(sizeof(bNodeLink), "internal node link");
-				ilink->fromnode = node;
-				ilink->fromsock = fromsock;
-				ilink->tonode = node;
-				ilink->tosock = tosock;
-				/* internal link is always valid */
-				ilink->flag |= NODE_LINK_VALID;
-				BLI_addtail(&node->internal_links, ilink);
-				
-				++num_reconnect;
-			}
+		
+		if (selected) {
+			bNodeLink *ilink = MEM_callocN(sizeof(bNodeLink), "internal node link");
+			ilink->fromnode = node;
+			ilink->fromsock = selected;
+			ilink->tonode = node;
+			ilink->tosock = output;
+			/* internal link is always valid */
+			ilink->flag |= NODE_LINK_VALID;
+			BLI_addtail(&node->internal_links, ilink);
 		}
 	}
 	
-	/* if there is one input and one output link, but no reconnections by type,
-	 * simply connect those two sockets.
-	 */
-	if ((num_reconnect == 0) && (num_links_in == 1) && (num_links_out == 1)) {
-		bNodeLink *ilink = MEM_callocN(sizeof(bNodeLink), "internal node link");
-		ilink->fromnode = node;
-		ilink->fromsock = fromsock_first;
-		ilink->tonode = node;
-		ilink->tosock = tosock_first;
-		/* internal link is always valid */
-		ilink->flag |= NODE_LINK_VALID;
-		BLI_addtail(&node->internal_links, ilink);
-	}
+	/* clean up */
+	for (output = node->outputs.first; output; output = output->next)
+		output->link = NULL;
 }
 
 float node_socket_get_float(bNodeTree *ntree, bNode *UNUSED(node), bNodeSocket *sock)