Cycles: add Object Info node, with outputs object location, object/material

pass index, and a random number unique to the instance of the object.

This can be useful to give some variation to a single material assigned to
multiple instances, either manually controlled through the object index, based
on the object location, or randomized for each instance. 

http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/More#Object_Info	

4 files changed, 56 insertions, 2 deletions

diff --git a/intern/cycles/render/nodes.cpp b/intern/cycles/render/nodes.cpp
index 57fe2fb01b7..506458d82e1 100644
--- a/intern/cycles/render/nodes.cpp
+++ b/intern/cycles/render/nodes.cpp
@@ -1699,7 +1699,7 @@ void LightPathNode::compile(OSLCompiler& compiler)
 	compiler.add(this, "node_light_path");
 }
 
-/* Light Path */
+/* Light Falloff */
 
 LightFalloffNode::LightFalloffNode()
 : ShaderNode("light_path")
@@ -1746,6 +1746,49 @@ void LightFalloffNode::compile(OSLCompiler& compiler)
 	compiler.add(this, "node_light_falloff");
 }
 
+/* Object Info */
+
+ObjectInfoNode::ObjectInfoNode()
+: ShaderNode("object_info")
+{
+	add_output("Location", SHADER_SOCKET_VECTOR);
+	add_output("Object Index", SHADER_SOCKET_FLOAT);
+	add_output("Material Index", SHADER_SOCKET_FLOAT);
+	add_output("Random", SHADER_SOCKET_FLOAT);
+}
+
+void ObjectInfoNode::compile(SVMCompiler& compiler)
+{
+	ShaderOutput *out = output("Location");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_OBJECT_INFO, NODE_INFO_OB_LOCATION, out->stack_offset);
+	}
+
+	out = output("Object Index");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_OBJECT_INFO, NODE_INFO_OB_INDEX, out->stack_offset);
+	}
+
+	out = output("Material Index");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_OBJECT_INFO, NODE_INFO_MAT_INDEX, out->stack_offset);
+	}
+
+	out = output("Random");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_OBJECT_INFO, NODE_INFO_OB_RANDOM, out->stack_offset);
+	}
+}
+
+void ObjectInfoNode::compile(OSLCompiler& compiler)
+{
+	compiler.add(this, "node_object_info");
+}
+
 /* Value */
 
 ValueNode::ValueNode()
diff --git a/intern/cycles/render/nodes.h b/intern/cycles/render/nodes.h
index ff9e3647d01..2d0d58d1e94 100644
--- a/intern/cycles/render/nodes.h
+++ b/intern/cycles/render/nodes.h
@@ -285,6 +285,11 @@ public:
 	SHADER_NODE_CLASS(LightFalloffNode)
 };
 
+class ObjectInfoNode : public ShaderNode {
+public:
+	SHADER_NODE_CLASS(ObjectInfoNode)
+};
+
 class ValueNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(ValueNode)
diff --git a/intern/cycles/render/object.cpp b/intern/cycles/render/object.cpp
index cae69c06f7d..e38b2635f90 100644
--- a/intern/cycles/render/object.cpp
+++ b/intern/cycles/render/object.cpp
@@ -23,6 +23,7 @@
 #include "scene.h"
 
 #include "util_foreach.h"
+#include "util_hash.h"
 #include "util_map.h"
 #include "util_progress.h"
 
@@ -36,6 +37,7 @@ Object::Object()
 	mesh = NULL;
 	tfm = transform_identity();
 	visibility = ~0;
+	instance_id = 0;
 	pass_id = 0;
 	bounds = BoundBox::empty;
 	motion.pre = transform_identity();
@@ -164,6 +166,9 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 		float surface_area = 0.0f;
 		float pass_id = ob->pass_id;
 		
+		uint ob_hash = hash_int_2d(hash_string(ob->name.c_str()), ob->instance_id);
+		float random_number = (float)ob_hash * (1.0f/(float)0xFFFFFFFF);
+		
 		if(transform_uniform_scale(tfm, uniform_scale)) {
 			map<Mesh*, float>::iterator it = surface_area_map.find(mesh);
 
@@ -198,7 +203,7 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 
 		memcpy(&objects[offset], &tfm, sizeof(float4)*3);
 		memcpy(&objects[offset+3], &itfm, sizeof(float4)*3);
-		objects[offset+6] = make_float4(surface_area, pass_id, 0.0f, 0.0f);
+		objects[offset+6] = make_float4(surface_area, pass_id, random_number, 0.0f);
 
 		if(need_motion == Scene::MOTION_PASS) {
 			/* motion transformations, is world/object space depending if mesh
diff --git a/intern/cycles/render/object.h b/intern/cycles/render/object.h
index 267052bfca7..b8169e3758e 100644
--- a/intern/cycles/render/object.h
+++ b/intern/cycles/render/object.h
@@ -41,6 +41,7 @@ public:
 	Transform tfm;
 	BoundBox bounds;
 	ustring name;
+	int instance_id;
 	int pass_id;
 	vector<ParamValue> attributes;
 	uint visibility;