Cycles: Remove Emission shaders from the graph if color or strength is 0.

1 files changed, 15 insertions, 0 deletions

diff --git a/intern/cycles/render/graph.cpp b/intern/cycles/render/graph.cpp
index ab89ee3ae37..9adf6b4b1ed 100644
--- a/intern/cycles/render/graph.cpp
+++ b/intern/cycles/render/graph.cpp
@@ -404,6 +404,21 @@ void ShaderGraph::remove_unneeded_nodes()
 				}
 			}
 		}
+		else if(node->special_type == SHADER_SPECIAL_TYPE_EMISSION) {
+			EmissionNode *em = static_cast<EmissionNode*>(node);
+
+			if(em->outputs[0]->links.size()) {
+				/* Black color or zero strength, remove node */
+				if((!em->inputs[0]->link && em->inputs[0]->value == make_float3(0.0f, 0.0f, 0.0f)) ||
+				   (!em->inputs[1]->link && em->inputs[1]->value.x == 0.0f)) {
+					vector<ShaderInput*> inputs = em->outputs[0]->links;
+
+					relink(em->inputs, inputs, NULL);
+					removed[em->id] = true;
+					any_node_removed = true;
+				}
+			}
+		}
 		else if(node->special_type == SHADER_SPECIAL_TYPE_MIX_CLOSURE) {
 			MixClosureNode *mix = static_cast<MixClosureNode*>(node);