== Python Button Evaluation ==

Users can write any valid Python expression (that evals to an int or float) inside Blender's gui number buttons (preceded by #) and have them evaluated to their actual int or float value.

Button Evaluation has access to the same modules as PyDrivers.

For example:

#1.0*9-2.3
#ob("Camera").LocZ
#1.0/ob("Cube").LocX
#math.sin(math.pi) -- or simply #m.sin(m.pi)
etc

source/blender/python/BPY_extern.h

@@ -85,6 +85,8 @@ extern "C" {
 	float BPY_pydriver_eval(struct IpoDriver *driver);
 	struct Object **BPY_pydriver_get_objects(struct IpoDriver *driver);
 
+	int BPY_button_eval(char *expr, double *value);
+
 /* format importer hook */
 	int BPY_call_importloader( char *name );