Cycles: change material output displacement to vector.

Previously only scalar displacement along the normal was supported,
now displacement can go in any direction. For backwards compatibility,
a Displacement node will be automatically inserted in existing files.

This will make it possible to support vector displacement maps in the
future. It's already possible to use them to some extent, but requires
a manual shader node setup. For tangent space maps the right tangent
may also not be available yet, depends on the map.

Differential Revision: https://developer.blender.org/D3015

1 files changed, 25 insertions, 6 deletions

diff --git a/intern/cycles/render/graph.cpp b/intern/cycles/render/graph.cpp
index 56434b39da5..fb2e34c2fc7 100644
--- a/intern/cycles/render/graph.cpp
+++ b/intern/cycles/render/graph.cpp
@@ -526,10 +526,10 @@ void ShaderGraph::constant_fold()
 	 * that happens to ensure there is still a valid graph for displacement.
 	 */
 	if(has_displacement && !output()->input("Displacement")->link) {
-		ValueNode *value = (ValueNode*)add(new ValueNode());
+		ColorNode *value = (ColorNode*)add(new ColorNode());
 		value->value = output()->displacement;
 
-		connect(value->output("Value"), output()->input("Displacement"));
+		connect(value->output("Color"), output()->input("Displacement"));
 	}
 }
 
@@ -861,7 +861,7 @@ void ShaderGraph::bump_from_displacement(bool use_object_space)
 
 	if(!displacement_in->link)
 		return;
-	
+
 	/* find dependencies for the given input */
 	ShaderNodeSet nodes_displace;
 	find_dependencies(nodes_displace, displacement_in);
@@ -893,15 +893,34 @@ void ShaderGraph::bump_from_displacement(bool use_object_space)
 	/* add bump node and connect copied graphs to it */
 	BumpNode *bump = (BumpNode*)add(new BumpNode());
 	bump->use_object_space = use_object_space;
+	bump->distance = 1.0f;
 
 	ShaderOutput *out = displacement_in->link;
 	ShaderOutput *out_center = nodes_center[out->parent]->output(out->name());
 	ShaderOutput *out_dx = nodes_dx[out->parent]->output(out->name());
 	ShaderOutput *out_dy = nodes_dy[out->parent]->output(out->name());
 
-	connect(out_center, bump->input("SampleCenter"));
-	connect(out_dx, bump->input("SampleX"));
-	connect(out_dy, bump->input("SampleY"));
+	/* convert displacement vector to height */
+	VectorMathNode *dot_center = (VectorMathNode*)add(new VectorMathNode());
+	VectorMathNode *dot_dx = (VectorMathNode*)add(new VectorMathNode());
+	VectorMathNode *dot_dy = (VectorMathNode*)add(new VectorMathNode());
+
+	dot_center->type = NODE_VECTOR_MATH_DOT_PRODUCT;
+	dot_dx->type = NODE_VECTOR_MATH_DOT_PRODUCT;
+	dot_dy->type = NODE_VECTOR_MATH_DOT_PRODUCT;
+
+	GeometryNode *geom = (GeometryNode*)add(new GeometryNode());
+	connect(geom->output("Normal"), dot_center->input("Vector2"));
+	connect(geom->output("Normal"), dot_dx->input("Vector2"));
+	connect(geom->output("Normal"), dot_dy->input("Vector2"));
+
+	connect(out_center, dot_center->input("Vector1"));
+	connect(out_dx, dot_dx->input("Vector1"));
+	connect(out_dy, dot_dy->input("Vector1"));
+
+	connect(dot_center->output("Value"), bump->input("SampleCenter"));
+	connect(dot_dx->output("Value"), bump->input("SampleX"));
+	connect(dot_dy->output("Value"), bump->input("SampleY"));
 	
 	/* connect the bump out to the set normal in: */
 	connect(bump->output("Normal"), set_normal->input("Direction"));