Index: source/blender/blenkernel/BKE_node.h
===================================================================
--- source/blender/blenkernel/BKE_node.h	(revision 13986)
+++ source/blender/blenkernel/BKE_node.h	(working copy)
@@ -46,6 +46,7 @@
 struct ListBase;
 struct RenderData;
 struct Scene;
+struct FileData;
 
 #define SOCK_IN		1
 #define SOCK_OUT	2
@@ -221,6 +222,7 @@
 #define SH_NODE_INVERT		119
 #define SH_NODE_SEPRGB		120
 #define SH_NODE_COMBRGB		121
+#define SH_NODE_EXPR		303
 #define SH_NODE_HUE_SAT		122
 #define NODE_DYNAMIC		123
 
Index: source/blender/blenkernel/intern/node.c
===================================================================
--- source/blender/blenkernel/intern/node.c	(revision 13986)
+++ source/blender/blenkernel/intern/node.c	(working copy)
@@ -2548,6 +2548,7 @@
 	nodeRegisterType(ntypelist, &sh_node_texture);
 	nodeRegisterType(ntypelist, &node_dynamic_typeinfo);
 	nodeRegisterType(ntypelist, &sh_node_invert);
+	nodeRegisterType(ntypelist, &sh_node_expr);
 	nodeRegisterType(ntypelist, &sh_node_seprgb);
 	nodeRegisterType(ntypelist, &sh_node_combrgb);
 	nodeRegisterType(ntypelist, &sh_node_hue_sat);
Index: source/blender/makesdna/DNA_node_types.h
===================================================================
--- source/blender/makesdna/DNA_node_types.h	(revision 13986)
+++ source/blender/makesdna/DNA_node_types.h	(working copy)
@@ -251,6 +251,27 @@
 	char name[32];
 } NodeVertexCol;
 
+typedef struct NodeExprComponent{
+	char fx[256];
+	char fy[256];
+	char fz[256];
+	char fw[256];
+	void *cx;
+	void *cy;
+	void *cz;
+	void *cw;
+	void *dict;
+} NodeExprTemp;
+
+typedef struct NodeExpr {
+	char fx[256];
+	char fy[256];
+	char fz[256];
+	char fw[256];
+	NodeExprTemp *temp;
+} NodeExpr;
+
+
 /* qdn: Defocus blur node */
 typedef struct NodeDefocus {
 	char bktype, rotation, preview, gamco;
Index: source/blender/src/drawnode.c
===================================================================
--- source/blender/src/drawnode.c	(revision 13986)
+++ source/blender/src/drawnode.c	(working copy)
@@ -775,6 +775,20 @@
 	return 40;
 }
 
+static int node_shader_buts_expr(uiBlock *block, bNodeTree *ntree, bNode *node, rctf *butr)
+{
+	if(block) {
+		NodeExpr *nexpr= (NodeExpr*)node->storage;
+
+		uiDefBut(block, TEX, B_NODE_EXEC+node->nr, "fx:", butr->xmin, butr->ymin+60, butr->xmax-butr->xmin, 20, nexpr->fx, 0, 255, 0, 0, "fx(x,y,z,w), Must evaluate to a Float");
+		uiDefBut(block, TEX, B_NODE_EXEC+node->nr, "fy:", butr->xmin, butr->ymin+40, butr->xmax-butr->xmin, 20, nexpr->fy, 0, 255, 0, 0, "fy(x,y,z,w), Must evaluate to a Float");
+		uiDefBut(block, TEX, B_NODE_EXEC+node->nr, "fz:", butr->xmin, butr->ymin+20, butr->xmax-butr->xmin, 20, nexpr->fz, 0, 255, 0, 0, "fz(x,y,z,w), Must evaluate to a Float");
+		uiDefBut(block, TEX, B_NODE_EXEC+node->nr, "fw:", butr->xmin, butr->ymin   , butr->xmax-butr->xmin, 20, nexpr->fw, 0, 255, 0, 0, "fw(x,y,z,w), Must evaluate to a Float");
+	}
+
+	return 80;
+}
+
 static int node_shader_buts_dynamic(uiBlock *block, bNodeTree *ntree, bNode *node, rctf *butr) 
 { 
 	if (block) { 
@@ -857,6 +871,9 @@
 		case SH_NODE_GEOMETRY:
 			ntype->butfunc= node_shader_buts_geometry;
 			break;
+		case SH_NODE_EXPR:
+			ntype->butfunc= node_shader_buts_expr;
+			break;
 		case NODE_DYNAMIC:
 			ntype->butfunc= node_shader_buts_dynamic;
 			break;
Index: source/blender/blenloader/intern/readfile.c
===================================================================
--- source/blender/blenloader/intern/readfile.c	(revision 13986)
+++ source/blender/blenloader/intern/readfile.c	(working copy)
@@ -1438,6 +1438,11 @@
 	}
 }
 
+/* Reset node expr temp data */
+static void link_nodeexpr( struct FileData *fd, NodeExpr *storage ){
+	storage->temp = NULL;
+}
+
 /* ************ READ NODE TREE *************** */
 
 /* singe node tree (also used for material/scene trees), ntree is not NULL */
@@ -1520,11 +1525,13 @@
 
 		node->storage= newdataadr(fd, node->storage);
 		if(node->storage) {
-			
 			/* could be handlerized at some point */
-			if(ntree->type==NTREE_SHADER && (node->type==SH_NODE_CURVE_VEC || node->type==SH_NODE_CURVE_RGB))
-				direct_link_curvemapping(fd, node->storage);
-			else if(ntree->type==NTREE_COMPOSIT) {
+			if( ntree->type==NTREE_SHADER ){
+				if( node->type==SH_NODE_CURVE_VEC || node->type==SH_NODE_CURVE_RGB )
+					direct_link_curvemapping(fd, node->storage);
+				else if ( node->type==SH_NODE_EXPR )
+					link_nodeexpr( fd, node->storage );
+			}else if(ntree->type==NTREE_COMPOSIT) {
 				if( ELEM3(node->type, CMP_NODE_TIME, CMP_NODE_CURVE_VEC, CMP_NODE_CURVE_RGB))
 					direct_link_curvemapping(fd, node->storage);
 				else if(ELEM3(node->type, CMP_NODE_IMAGE, CMP_NODE_VIEWER, CMP_NODE_SPLITVIEWER))
Index: source/blender/nodes/intern/SHD_nodes/SHD_expr.c
===================================================================
--- source/blender/nodes/intern/SHD_nodes/SHD_expr.c	(revision 0)
+++ source/blender/nodes/intern/SHD_nodes/SHD_expr.c	(revision 0)
@@ -0,0 +1,206 @@
+/**
+  *
+ * ***** 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The Original Code is Copyright (C) 2005 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+#include <Python.h>
+#include <eval.h>
+
+#include "../SHD_util.h"
+
+static bNodeSocketType sh_node_expr_in[]= {
+	{	SOCK_VECTOR, 1, "(x,y,z)", 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f },
+	{	SOCK_VALUE, 1, "w", 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f },
+	{	-1, 0, ""	}
+};
+
+static bNodeSocketType sh_node_expr_out[]= {
+	{	SOCK_VECTOR, 0, "(fx,fy,fz)", 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f },
+	{	SOCK_VALUE, 0, "fw", 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f },
+	{	-1, 0, ""	}
+};
+
+static void node_expr_add_temp( NodeExpr *ne ){
+	NodeExprTemp *net = (NodeExprTemp*)MEM_callocN(sizeof(NodeExprTemp), "NodeExprTemp");
+	memset( net, 0, sizeof(NodeExprTemp) );
+	
+	ne->temp = net;
+	ne->temp->dict = PyDict_New();
+
+	PyObject *module_random = PyImport_ImportModule("random");
+	PyObject *module_math = PyImport_ImportModule("math");
+	PyObject *module_cmath = PyImport_ImportModule("cmath");
+	if (module_random){ PyDict_SetItemString( ne->temp->dict, "random", module_random ); Py_DECREF( module_random ); }
+	if (module_math){   PyDict_SetItemString( ne->temp->dict, "math", module_math );     Py_DECREF( module_math ); }
+	if (module_cmath){  PyDict_SetItemString( ne->temp->dict, "cmath", module_cmath );   Py_DECREF( module_cmath ); }
+}
+
+
+static void node_shader_init_expr( bNode *node ){
+	NodeExpr *ne = (NodeExpr*)MEM_callocN(sizeof(NodeExpr), "NodeExpr");
+	memset( ne, 0, sizeof(NodeExpr) );
+
+	PyGILState_STATE gstate;
+    gstate = PyGILState_Ensure();
+    
+    node_expr_add_temp( ne );
+
+    PyGILState_Release(gstate);
+
+	node->storage = ne;
+}
+
+
+static void node_expr_free(bNode *node)
+{
+	NodeExpr *ne = (NodeExpr*)(node->storage);
+
+//	PyGILState_STATE gstate;
+//    gstate = PyGILState_Ensure();
+    
+    Py_XDECREF( (PyObject *)( ne->temp->cx ) );
+	Py_XDECREF( (PyObject *)( ne->temp->cy ) );
+	Py_XDECREF( (PyObject *)( ne->temp->cz ) );
+	Py_XDECREF( (PyObject *)( ne->temp->cw ) );
+	Py_XDECREF( (PyObject *)( ne->temp->dict ) );
+	
+//	PyGILState_Release(gstate);
+
+	MEM_freeN( ne->temp );
+	MEM_freeN( node->storage );
+}
+
+static void node_expr_copy(bNode *orig_node, bNode *new_node)
+{
+	PyGILState_STATE gstate;
+    gstate = PyGILState_Ensure();
+
+    new_node->storage= MEM_dupallocN(orig_node->storage);
+	node_expr_add_temp( (NodeExpr*)new_node->storage );
+
+	PyGILState_Release(gstate);
+}
+
+
+static void node_shader_exec_expr( void *data, bNode *node, bNodeStack **in, bNodeStack **out )
+{
+	float vec[4];
+	PyGILState_STATE gstate;
+    gstate = PyGILState_Ensure();
+
+	NodeExpr *ne = (NodeExpr*)node->storage;
+	
+	if ( !ne ){
+		PyGILState_Release(gstate);
+		return;
+	}
+	if ( !ne->temp )
+		node_expr_add_temp( ne );
+
+    nodestack_get_vec(vec, SOCK_VECTOR, in[0]);
+    nodestack_get_vec(vec+3, SOCK_VALUE, in[1]);
+	
+	PyObject *dict = (PyObject*)ne->temp->dict;
+	
+	if ( !dict ){
+		PyGILState_Release(gstate);
+		return;
+	}
+    
+	PyObject *x = PyFloat_FromDouble( vec[0] );
+	PyObject *y = PyFloat_FromDouble( vec[1] );
+	PyObject *z = PyFloat_FromDouble( vec[2] );	
+	PyObject *w = PyFloat_FromDouble( vec[3] );
+	
+	PyDict_SetItemString( dict, "x", x );
+	PyDict_SetItemString( dict, "y", y );
+	PyDict_SetItemString( dict, "z", z );
+	PyDict_SetItemString( dict, "w", w );
+	
+
+	#define COMPILE_EXPR( coord ) {\
+		if ( strncmp( ne->f##coord, ne->temp->f##coord, 256 ) ){ \
+			ne->temp->c##coord = Py_CompileString( ne->f##coord, "node_expr", Py_eval_input ); \
+			BLI_strncpy( ne->temp->f##coord, ne->f##coord, 256 ); \
+		}}
+	
+	COMPILE_EXPR( x );
+	COMPILE_EXPR( y );
+	COMPILE_EXPR( z );
+	COMPILE_EXPR( w );	
+
+    PyObject *fx = (ne->temp->cx) ? PyEval_EvalCode( ne->temp->cx, dict, dict ) : NULL;
+	PyObject *fy = (ne->temp->cy) ? PyEval_EvalCode( ne->temp->cy, dict, dict ) : NULL;
+	PyObject *fz = (ne->temp->cz) ? PyEval_EvalCode( ne->temp->cz, dict, dict ) : NULL;
+	PyObject *fw = (ne->temp->cw) ? PyEval_EvalCode( ne->temp->cw, dict, dict ) : NULL;
+
+    if(! fx && fy && fz && fw) {
+		if(PyErr_Occurred()) {
+			PyErr_Print();
+		}
+		Py_XDECREF(fx);
+		Py_XDECREF(fy);
+		Py_XDECREF(fz);
+		Py_XDECREF(fw);
+		Py_XDECREF(x);
+		Py_XDECREF(y);
+		Py_XDECREF(z);
+		Py_XDECREF(w);
+	    PyGILState_Release(gstate);
+		return;
+	}
+
+	out[0]->vec[0] = PyFloat_AsDouble( fx );
+	out[0]->vec[1] = PyFloat_AsDouble( fy );
+	out[0]->vec[2] = PyFloat_AsDouble( fz );
+	out[1]->vec[0] = PyFloat_AsDouble( fw );
+	
+	Py_XDECREF(fx);
+	Py_XDECREF(fy);
+	Py_XDECREF(fz);
+	Py_XDECREF(fw);
+	Py_XDECREF(x);
+	Py_XDECREF(y);
+	Py_XDECREF(z);
+	Py_XDECREF(w);
+    PyGILState_Release(gstate);
+}
+
+bNodeType sh_node_expr= {
+	/* *next,*prev */	NULL, NULL,
+	/* type code   */	SH_NODE_EXPR,
+	/* name        */	"Python expression",
+	/* width+range */	100, 60, 140,
+	/* class+opts  */	NODE_CLASS_OP_VECTOR, NODE_OPTIONS,
+	/* input sock  */	sh_node_expr_in,
+	/* output sock */	sh_node_expr_out,
+	/* storage     */	"NodeExpr",
+	/* execfunc    */	node_shader_exec_expr,
+	/* butfunc     */	NULL,
+	/* initfunc    */	node_shader_init_expr,
+	/* freestoragefunc    */	node_expr_free,
+	/* copystoragefunc    */	node_expr_copy,
+	/* id          */	NULL
+};
Index: source/blender/nodes/intern/SHD_nodes/Makefile
===================================================================
--- source/blender/nodes/intern/SHD_nodes/Makefile	(revision 13986)
+++ source/blender/nodes/intern/SHD_nodes/Makefile	(working copy)
@@ -47,4 +47,5 @@
 CPPFLAGS += -I../../../include
 CPPFLAGS += -I../../../imbuf
 CPPFLAGS += -I../../../render/extern/include
+CPPFLAGS += -I$(NAN_PYTHON)/include/python$(NAN_PYTHON_VERSION)
 CPPFLAGS += -I$(OPENGL_HEADERS)
Index: source/blender/nodes/SHD_node.h
===================================================================
--- source/blender/nodes/SHD_node.h	(revision 13986)
+++ source/blender/nodes/SHD_node.h	(working copy)
@@ -32,7 +32,6 @@
 
 #ifndef SHD_NODE_H
 #define SHD_NODE_H
-
 #include "BKE_node.h"
 
 
@@ -61,6 +60,7 @@
 extern bNodeType sh_node_invert;
 extern bNodeType sh_node_seprgb;
 extern bNodeType sh_node_combrgb;
+extern bNodeType sh_node_expr;
 extern bNodeType sh_node_hue_sat;
 
 #endif
Index: source/blender/nodes/CMakeLists.txt
===================================================================
--- source/blender/nodes/CMakeLists.txt	(revision 13986)
+++ source/blender/nodes/CMakeLists.txt	(working copy)
@@ -34,6 +34,7 @@
   ../imbuf ../avi ../../../intern/elbeem/extern
   ../../../intern/iksolver/extern ../blenloader ../quicktime
   ../blenkernel
+  ${PYTHON_INC}
   ${SDL_INC}
   ${ZLIB_INC}
   ${PYTHON_INC}
@@ -69,4 +70,3 @@
 IF(WITH_INTERNATIONAL)
    ADD_DEFINITIONS(-DWITH_FREETYPE2)
 ENDIF(WITH_INTERNATIONAL)
-