pydrivers: 'frame' is now in the driver namespace,

- no need to link to scenes when using a frame from the pydriver, this made linking rigs for eg, quite messy.
- advantage that we get subframe values (where scenes from was fixed to a whole number).

source/blender/blenkernel/intern/fcurve.c

@@ -1576,7 +1576,7 @@ float driver_get_variable_value (ChannelDriver *driver, DriverVar *dvar)
  *	- "evaltime" is the frame at which F-Curve is being evaluated
  * 	- has to return a float value 
  */
-static float evaluate_driver (ChannelDriver *driver, float UNUSED(evaltime))
+static float evaluate_driver (ChannelDriver *driver, const float evaltime)
 {
 	DriverVar *dvar;
 	
@@ -1663,8 +1663,10 @@ static float evaluate_driver (ChannelDriver *driver, float UNUSED(evaltime))
 				/* this evaluates the expression using Python,and returns its result:
 				 * 	- on errors it reports, then returns 0.0f
 				 */
-				driver->curval= BPY_driver_exec(driver);
+				driver->curval= BPY_driver_exec(driver, evaltime);
 			}
+#else /* WITH_PYTHON*/
+		(void)evaltime;
 #endif /* WITH_PYTHON*/
 		}
 			break;
@@ -2087,7 +2089,7 @@ static float fcurve_eval_samples (FCurve *fcu, FPoint *fpts, float evaltime)
 /* Evaluate and return the value of the given F-Curve at the specified frame ("evaltime") 
  * Note: this is also used for drivers
  */
-float evaluate_fcurve (FCurve *fcu, float evaltime) 
+float evaluate_fcurve (FCurve *fcu, float evaltime)
 {
 	float cvalue= 0.0f;
 	float devaltime;

source/blender/editors/interface/interface_anim.c

@@ -164,24 +164,7 @@ int ui_but_anim_expression_create(uiBut *but, const char *str)
 			/* set the expression */
 			// TODO: need some way of identifying variables used
 			BLI_strncpy_utf8(driver->expression, str, sizeof(driver->expression));
-			
-			/* FIXME: for now, assume that 
-			 * 	- for expressions, users are likely to be using "frame" -> current frame" as a variable
-			 *	- driver_add_new_variable() adds a single-prop variable by default
-			 */
-			{
-				DriverVar *dvar;
-				DriverTarget *dtar;
-				
-				dvar = driver_add_new_variable(driver);
-				BLI_strncpy(dvar->name, "frame", sizeof(dvar->name));
-				
-				dtar = &dvar->targets[0];
-				dtar->id = (ID *)CTX_data_scene(C); // XXX: should we check that C is valid first?
-				dtar->idtype= ID_SCE;
-				dtar->rna_path = BLI_sprintfN("frame_current");
-			}
-			
+
 			/* updates */
 			driver->flag |= DRIVER_FLAG_RECOMPILE;
 			WM_event_add_notifier(C, NC_ANIMATION|ND_KEYFRAME, NULL);

source/blender/python/BPY_extern.h

@@ -74,7 +74,7 @@ void	BPY_modules_load_user(struct bContext *C);
 void	BPY_app_handlers_reset(const short do_all);
 
 void	BPY_driver_reset(void);
-float	BPY_driver_exec(struct ChannelDriver *driver);
+float	BPY_driver_exec(struct ChannelDriver *driver, const float evaltime);
 
 int		BPY_button_exec(struct bContext *C, const char *expr, double *value, const short verbose);
 int		BPY_string_exec(struct bContext *C, const char *expr);

source/blender/python/intern/bpy_driver.c

@@ -91,6 +91,29 @@ int bpy_pydriver_create_dict(void)
 	return 0;
 }
 
+/* note, this function should do nothing most runs, only when changing frame */
+static PyObject *bpy_pydriver_InternStr__frame= NULL;
+
+static void bpy_pydriver_update_dict(const float evaltime)
+{
+	/* not thread safe but neither is python */
+	static float evaltime_prev= FLT_MAX;
+
+	if (evaltime_prev != evaltime) {
+
+		/* currently only update the frame */
+		if (bpy_pydriver_InternStr__frame == NULL) {
+			bpy_pydriver_InternStr__frame= PyUnicode_FromString("frame");
+		}
+
+		PyDict_SetItem(bpy_pydriver_Dict,
+		               bpy_pydriver_InternStr__frame,
+		               PyFloat_FromDouble(evaltime));
+
+		evaltime_prev= evaltime;
+	}
+}
+
 /* Update function, it gets rid of pydrivers global dictionary, forcing
  * BPY_driver_exec to recreate it. This function is used to force
  * reloading the Blender text module "pydrivers.py", if available, so
@@ -110,6 +133,11 @@ void BPY_driver_reset(void)
 		bpy_pydriver_Dict= NULL;
 	}
 
+	if (bpy_pydriver_InternStr__frame) {
+		Py_DECREF(bpy_pydriver_InternStr__frame);
+		bpy_pydriver_InternStr__frame= NULL;
+	}
+
 	if (use_gil)
 		PyGILState_Release(gilstate);
 
@@ -139,7 +167,7 @@ static void pydriver_error(ChannelDriver *driver)
  * now release the GIL on python operator execution instead, using
  * PyEval_SaveThread() / PyEval_RestoreThread() so we dont lock up blender.
  */
-float BPY_driver_exec(ChannelDriver *driver)
+float BPY_driver_exec(ChannelDriver *driver, const float evaltime)
 {
 	PyObject *driver_vars=NULL;
 	PyObject *retval= NULL;
@@ -183,6 +211,10 @@ float BPY_driver_exec(ChannelDriver *driver)
 		}
 	}
 
+	/* update global namespace */
+	bpy_pydriver_update_dict(evaltime);
+
+
 	if (driver->expr_comp==NULL)
 		driver->flag |= DRIVER_FLAG_RECOMPILE;
 
@@ -246,6 +278,7 @@ float BPY_driver_exec(ChannelDriver *driver)
 		}
 	}
 
+
 #if 0 // slow, with this can avoid all Py_CompileString above.
 	/* execute expression to get a value */
 	retval= PyRun_String(expr, Py_eval_input, bpy_pydriver_Dict, driver_vars);

source/blender/python/intern/bpy_driver.h

@@ -33,7 +33,7 @@ int bpy_pydriver_create_dict(void);
 extern PyObject *bpy_pydriver_Dict;
 
 /* externals */
-float BPY_driver_exec(struct ChannelDriver *driver);
+float BPY_driver_exec(struct ChannelDriver *driver, const float evaltime);
 void BPY_driver_reset(void);
 
 #endif // BPY_DRIVER_H

source/blenderplayer/bad_level_call_stubs/stubs.c

@@ -454,7 +454,7 @@ void BPY_text_free_code(struct Text *text) {}
 void BPY_id_release(struct Text *text) {}
 int BPY_context_member_get(struct Context *C, const char *member, struct bContextDataResult *result) { return 0; }
 void BPY_pyconstraint_target(struct bPythonConstraint *con, struct bConstraintTarget *ct) {}
-float BPY_driver_exec(struct ChannelDriver *driver) {return 0.0f;} /* might need this one! */
+float BPY_driver_exec(struct ChannelDriver *driver, const float evaltime) {return 0.0f;} /* might need this one! */
 void BPY_DECREF(void *pyob_ptr) {}
 void BPY_pyconstraint_exec(struct bPythonConstraint *con, struct bConstraintOb *cob, struct ListBase *targets) {}
 void macro_wrapper(struct wmOperatorType *ot, void *userdata) {} ;