Blender Internal: Add "Lamp Data" shader node that allows shaders to acquire information such as light vector from specified Lamp.

For now this provides the following outputs:

- Color
- Light Vector
- Distance
- Shadow
- Visibility Factor

Note: Color output is multiplied by the lamp energy.  Multiplication of
color*max(dot(light_vector,normal_vector),0)*shadow*visibility_factor
produces the exact same result as the Lambert shader.

Many thanks to Brecht for code review and discussion!

4 files changed, 89 insertions, 0 deletions

diff --git a/source/blender/nodes/CMakeLists.txt b/source/blender/nodes/CMakeLists.txt
index 61c8cb5655d..64feb0068cb 100644
--- a/source/blender/nodes/CMakeLists.txt
+++ b/source/blender/nodes/CMakeLists.txt
@@ -133,6 +133,7 @@ set(SRC
 	shader/nodes/node_shader_geom.c
 	shader/nodes/node_shader_hueSatVal.c
 	shader/nodes/node_shader_invert.c
+	shader/nodes/node_shader_lamp.c
 	shader/nodes/node_shader_mapping.c
 	shader/nodes/node_shader_material.c
 	shader/nodes/node_shader_math.c
diff --git a/source/blender/nodes/NOD_shader.h b/source/blender/nodes/NOD_shader.h
index 853046a2a23..71c0638829f 100644
--- a/source/blender/nodes/NOD_shader.h
+++ b/source/blender/nodes/NOD_shader.h
@@ -47,6 +47,7 @@ void register_node_type_sh_group(void);
 void register_node_type_sh_output(void);
 void register_node_type_sh_material(void);
 void register_node_type_sh_camera(void);
+void register_node_type_sh_lamp(void);
 void register_node_type_sh_value(void);
 void register_node_type_sh_rgb(void);
 void register_node_type_sh_mix_rgb(void);
diff --git a/source/blender/nodes/NOD_static_types.h b/source/blender/nodes/NOD_static_types.h
index db9f710b6cf..beeaa7787fb 100644
--- a/source/blender/nodes/NOD_static_types.h
+++ b/source/blender/nodes/NOD_static_types.h
@@ -56,6 +56,7 @@ DefNode( ShaderNode,     SH_NODE_MAPPING,         def_sh_mapping,         "MAPPI
 DefNode( ShaderNode,     SH_NODE_CURVE_VEC,       def_vector_curve,       "CURVE_VEC",      VectorCurve,      "Vector Curves",     ""              )
 DefNode( ShaderNode,     SH_NODE_CURVE_RGB,       def_rgb_curve,          "CURVE_RGB",      RGBCurve,         "RGB Curves",        ""              )
 DefNode( ShaderNode,     SH_NODE_CAMERA,          0,                      "CAMERA",         CameraData,       "Camera Data",       ""              )
+DefNode( ShaderNode,     SH_NODE_LAMP,            def_sh_lamp,            "LAMP",           LampData,         "Lamp Data",         ""              )
 DefNode( ShaderNode,     SH_NODE_MATH,            def_math,               "MATH",           Math,             "Math",              ""              )
 DefNode( ShaderNode,     SH_NODE_VECT_MATH,       def_vector_math,        "VECT_MATH",      VectorMath,       "Vector Math",       ""              )
 DefNode( ShaderNode,     SH_NODE_SQUEEZE,         0,                      "SQUEEZE",        Squeeze,          "Squeeze Value",     ""              )
diff --git a/source/blender/nodes/shader/nodes/node_shader_lamp.c b/source/blender/nodes/shader/nodes/node_shader_lamp.c
new file mode 100644
index 00000000000..adf53ba9b52
--- /dev/null
+++ b/source/blender/nodes/shader/nodes/node_shader_lamp.c
@@ -0,0 +1,86 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version. 
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2013 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/nodes/shader/nodes/node_shader_lamp.c
+ *  \ingroup shdnodes
+ */
+
+
+#include "node_shader_util.h"
+
+/* **************** LAMP INFO  ******************** */
+static bNodeSocketTemplate sh_node_lamp_out[] = {
+	{	SOCK_RGBA, 0, N_("Color")},
+	{	SOCK_VECTOR, 0, N_("Light Vector")},
+	{	SOCK_FLOAT, 0, N_("Distance")},
+	{	SOCK_RGBA, 0, N_("Shadow")},
+	{	SOCK_FLOAT, 0, N_("Visibility Factor")},
+	{	-1, 0, ""	}
+};
+
+
+static void node_shader_exec_lamp(void *data, int UNUSED(thread), bNode *node, bNodeExecData *UNUSED(execdata), bNodeStack **UNUSED(in), bNodeStack **out)
+{
+	if (data) {
+		Object *ob = (Object *)node->id;
+
+		if (ob) {
+			ShadeInput *shi = ((ShaderCallData *)data)->shi;
+
+			shi->nodes = 1; /* temp hack to prevent trashadow recursion */
+			out[4]->vec[0] = RE_lamp_get_data(shi, ob, out[0]->vec, out[1]->vec, out[2]->vec, out[3]->vec);
+			shi->nodes = 0;
+		}
+	}
+}
+
+static int gpu_shader_lamp(GPUMaterial *mat, bNode *node, bNodeExecData *UNUSED(execdata), GPUNodeStack *in, GPUNodeStack *out)
+{
+	if (node->id) {
+		GPULamp *lamp = GPU_lamp_from_blender(GPU_material_scene(mat), (Object *)node->id, NULL);
+		GPUNodeLink *col, *lv, *dist, *visifac, *shadow;
+
+		visifac = GPU_lamp_get_data(mat, lamp, &col, &lv, &dist, &shadow);
+
+		return GPU_stack_link(mat, "lamp", in, out, col, lv, dist, shadow, visifac);
+	}
+
+	return 0;
+}
+
+void register_node_type_sh_lamp(void)
+{
+	static bNodeType ntype;
+
+	sh_node_type_base(&ntype, SH_NODE_LAMP, "Lamp Data", NODE_CLASS_INPUT, 0);
+	node_type_compatibility(&ntype, NODE_OLD_SHADING);
+	node_type_socket_templates(&ntype, NULL, sh_node_lamp_out);
+	node_type_exec(&ntype, NULL, NULL, node_shader_exec_lamp);
+	node_type_gpu(&ntype, gpu_shader_lamp);
+
+	nodeRegisterType(&ntype);
+}