Cycles: Fix for wrong optimization of bump node

It can't be simply removed in cases when it's connected to input which is
different from Normal. This is because the input wouldn't be connected to
default Normal geometry input, possibly breaking shading setup.

The fix is not really ideal, but should work at least.

This fixes skin having too much glossy reflection in the file from T46013.

1 files changed, 18 insertions, 5 deletions

diff --git a/intern/cycles/render/graph.cpp b/intern/cycles/render/graph.cpp
index e0537101247..f5ff091623b 100644
--- a/intern/cycles/render/graph.cpp
+++ b/intern/cycles/render/graph.cpp
@@ -336,6 +336,8 @@ void ShaderGraph::remove_unneeded_nodes()
 	vector<bool> removed(num_node_ids, false);
 	bool any_node_removed = false;
 
+	ShaderNode *geom = NULL;
+
 	/* find and unlink proxy nodes */
 	foreach(ShaderNode *node, nodes) {
 		if(node->special_type == SHADER_SPECIAL_TYPE_PROXY) {
@@ -423,12 +425,19 @@ void ShaderGraph::remove_unneeded_nodes()
 			BumpNode *bump = static_cast<BumpNode*>(node);
 
 			if(bump->outputs[0]->links.size()) {
-				/* Height input not connected */
-				/* ToDo: Strength zero? */
-				if(!bump->inputs[0]->link) {
+				/* Height inputs is not connected. */
+				/* TODO(sergey): Ignore bump with zero strength. */
+				if(bump->inputs[0]->link == NULL) {
 					vector<ShaderInput*> inputs = bump->outputs[0]->links;
-
-					relink(bump->inputs, inputs, NULL);
+					if(bump->inputs[4]->link == NULL) {
+						if(geom == NULL) {
+							geom = new GeometryNode();
+						}
+						relink(bump->inputs, inputs, geom->output("Normal"));
+					}
+					else {
+						relink(bump->inputs, inputs, bump->input("Normal")->link);
+					}
 					removed[bump->id] = true;
 					any_node_removed = true;
 				}
@@ -511,6 +520,10 @@ void ShaderGraph::remove_unneeded_nodes()
 
 		nodes = newnodes;
 	}
+
+	if(geom != NULL) {
+		add(geom);
+	}
 }
 
 void ShaderGraph::break_cycles(ShaderNode *node, vector<bool>& visited, vector<bool>& on_stack)