2.5 - Groundwork for Adding/Removing Drivers

Drivers can now be Added/Removed from buttons using the D/Alt-D hotkeys, and also through the menu. Driver settings (i.e. the target) are not set by default. To set those, go to the Graph Editor (see notes).

Notes:
* Buildsystem maintainers - I've added a new file "editors/animation/drivers.c"
* Widget colours for the driven-setting indications are needed 
* To see the new drivers, go into Graph Editor -> "Drivers" mode. Currently, there's a little bug there which prevents editing of the new drivers.

source/blender/editors/animation/anim_ops.c

@@ -386,6 +386,9 @@ void ED_operatortypes_anim(void)
 	WM_operatortype_append(ANIM_OT_delete_keyframe_button);
 	WM_operatortype_append(ANIM_OT_delete_keyframe_old); // xxx remove?
 	
+	WM_operatortype_append(ANIM_OT_add_driver_button);
+	WM_operatortype_append(ANIM_OT_remove_driver_button);
+	
 	WM_operatortype_append(ANIM_OT_keyingset_add_new);
 	WM_operatortype_append(ANIM_OT_keyingset_add_destination);
 }

source/blender/editors/animation/drivers.c

@@ -0,0 +1,289 @@
+/* Testing code for 2.5 animation system 
+ * Copyright 2009, Joshua Leung
+ */
+ 
+#include <stdio.h>
+#include <stddef.h>
+#include <string.h>
+#include <math.h>
+#include <float.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_arithb.h"
+#include "BLI_dynstr.h"
+
+#include "DNA_anim_types.h"
+#include "DNA_action_types.h"
+#include "DNA_armature_types.h"
+#include "DNA_constraint_types.h"
+#include "DNA_key_types.h"
+#include "DNA_object_types.h"
+#include "DNA_material_types.h"
+#include "DNA_scene_types.h"
+#include "DNA_userdef_types.h"
+#include "DNA_windowmanager_types.h"
+
+#include "BKE_animsys.h"
+#include "BKE_action.h"
+#include "BKE_constraint.h"
+#include "BKE_fcurve.h"
+#include "BKE_utildefines.h"
+#include "BKE_context.h"
+#include "BKE_report.h"
+#include "BKE_key.h"
+#include "BKE_material.h"
+
+#include "ED_anim_api.h"
+#include "ED_keyframing.h"
+#include "ED_keyframes_edit.h"
+#include "ED_screen.h"
+#include "ED_util.h"
+
+#include "UI_interface.h"
+
+#include "WM_api.h"
+#include "WM_types.h"
+
+#include "RNA_access.h"
+#include "RNA_define.h"
+#include "RNA_types.h"
+
+/* ************************************************** */
+/* Animation Data Validation */
+
+/* Get (or add relevant data to be able to do so) F-Curve from the driver stack, 
+ * for the given Animation Data block. This assumes that all the destinations are valid.
+ */
+FCurve *verify_driver_fcurve (ID *id, const char rna_path[], const int array_index, short add)
+{
+	AnimData *adt;
+	FCurve *fcu;
+	
+	/* sanity checks */
+	if ELEM(NULL, id, rna_path)
+		return NULL;
+	
+	/* init animdata if none available yet */
+	adt= BKE_animdata_from_id(id);
+	if ((adt == NULL) && (add))
+		adt= BKE_id_add_animdata(id);
+	if (adt == NULL) { 
+		/* if still none (as not allowed to add, or ID doesn't have animdata for some reason) */
+		return NULL;
+	}
+		
+	/* try to find f-curve matching for this setting 
+	 *	- add if not found and allowed to add one
+	 *		TODO: add auto-grouping support? how this works will need to be resolved
+	 */
+	fcu= list_find_fcurve(&adt->drivers, rna_path, array_index);
+	
+	if ((fcu == NULL) && (add)) {
+		/* use default settings to make a F-Curve */
+		fcu= MEM_callocN(sizeof(FCurve), "FCurve");
+		
+		fcu->flag = (FCURVE_VISIBLE|FCURVE_AUTO_HANDLES|FCURVE_SELECTED);
+		
+		/* store path - make copy, and store that */
+		fcu->rna_path= BLI_strdupn(rna_path, strlen(rna_path));
+		fcu->array_index= array_index;
+		
+		/* add some new driver data */
+		fcu->driver= MEM_callocN(sizeof(ChannelDriver), "ChannelDriver");
+		
+		/* just add F-Curve to end of driver list */
+		BLI_addtail(&adt->drivers, fcu);
+	}
+	
+	/* return the F-Curve */
+	return fcu;
+}
+
+/* ************************************************** */
+/* Driver Management API */
+
+/* Main Driver Management API calls:
+ * 	Add a new driver for the specified property on the given ID block
+ */
+short ANIM_add_driver (ID *id, const char rna_path[], int array_index, short flag)
+{	
+	PointerRNA id_ptr, ptr;
+	PropertyRNA *prop;
+	FCurve *fcu;
+	
+	/* validate pointer first - exit if failure */
+	RNA_id_pointer_create(id, &id_ptr);
+	if ((RNA_path_resolve(&id_ptr, rna_path, &ptr, &prop) == 0) || (prop == NULL)) {
+		printf("Insert Key: Could not add Driver, as RNA Path is invalid for the given ID (ID = %s, Path = %s)\n", id->name, rna_path);
+		return 0;
+	}
+	
+	/* create F-Curve with Driver */
+	fcu= verify_driver_fcurve(id, rna_path, array_index, 1);
+	
+	/* done */
+	return (fcu != NULL);
+}
+
+/* Main Driver Management API calls:
+ * 	Remove the driver for the specified property on the given ID block (if available)
+ */
+short ANIM_remove_driver (struct ID *id, const char rna_path[], int array_index, short flag)
+{
+	AnimData *adt;
+	FCurve *fcu;
+	
+	/* get F-Curve
+	 * Note: here is one of the places where we don't want new F-Curve + Driver added!
+	 * 		so 'add' var must be 0
+	 */
+	/* we don't check the validity of the path here yet, but it should be ok... */
+	fcu= verify_driver_fcurve(id, rna_path, array_index, 0);
+	adt= BKE_animdata_from_id(id);
+	
+	/* only continue if we have an driver to remove */
+	if (adt && fcu) {
+		/* remove F-Curve from driver stack, then free it */
+		BLI_remlink(&adt->drivers, fcu);
+		free_fcurve(fcu);
+		
+		/* done successfully */
+		return 1;
+	}
+	
+	/* failed */
+	return 0;
+}
+
+
+/* ************************************************** */
+/* UI-Button Interface */
+
+/* Add Driver Button Operator ------------------------ */
+
+static int add_driver_button_exec (bContext *C, wmOperator *op)
+{
+	PointerRNA ptr;
+	PropertyRNA *prop= NULL;
+	char *path;
+	short success= 0;
+	int a, index, length, all= RNA_boolean_get(op->ptr, "all");
+	
+	/* try to insert keyframe using property retrieved from UI */
+	memset(&ptr, 0, sizeof(PointerRNA));
+	uiAnimContextProperty(C, &ptr, &prop, &index);
+	
+	if (ptr.data && prop && RNA_property_animateable(ptr.data, prop)) {
+		path= RNA_path_from_ID_to_property(&ptr, prop);
+		
+		if (path) {
+			if (all) {
+				length= RNA_property_array_length(&ptr, prop);
+				
+				if (length) index= 0;
+				else length= 1;
+			}
+			else
+				length= 1;
+			
+			for (a=0; a<length; a++)
+				success+= ANIM_add_driver(ptr.id.data, path, index+a, 0);
+			
+			MEM_freeN(path);
+		}
+	}
+	
+	if (success) {
+		/* send updates */
+		ED_anim_dag_flush_update(C);	
+		
+		/* for now, only send ND_KEYS for KeyingSets */
+		WM_event_add_notifier(C, ND_KEYS, NULL); // XXX
+	}
+	
+	return (success)? OPERATOR_FINISHED: OPERATOR_CANCELLED;
+}
+
+void ANIM_OT_add_driver_button (wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Add Driver";
+	ot->idname= "ANIM_OT_add_driver_button";
+	
+	/* callbacks */
+	ot->exec= add_driver_button_exec; 
+	//op->poll= ???
+	
+	/* flags */
+	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
+
+	/* properties */
+	RNA_def_boolean(ot->srna, "all", 1, "All", "Insert a keyframe for all element of the array.");
+}
+
+/* Remove Driver Button Operator ------------------------ */
+
+static int remove_driver_button_exec (bContext *C, wmOperator *op)
+{
+	PointerRNA ptr;
+	PropertyRNA *prop= NULL;
+	char *path;
+	short success= 0;
+	int a, index, length, all= RNA_boolean_get(op->ptr, "all");
+	
+	/* try to insert keyframe using property retrieved from UI */
+	memset(&ptr, 0, sizeof(PointerRNA));
+	uiAnimContextProperty(C, &ptr, &prop, &index);
+
+	if (ptr.data && prop) {
+		path= RNA_path_from_ID_to_property(&ptr, prop);
+		
+		if (path) {
+			if (all) {
+				length= RNA_property_array_length(&ptr, prop);
+				
+				if(length) index= 0;
+				else length= 1;
+			}
+			else
+				length= 1;
+			
+			for (a=0; a<length; a++)
+				success+= ANIM_remove_driver(ptr.id.data, path, index+a, 0);
+			
+			MEM_freeN(path);
+		}
+	}
+	
+	
+	if (success) {
+		/* send updates */
+		ED_anim_dag_flush_update(C);	
+		
+		/* for now, only send ND_KEYS for KeyingSets */
+		WM_event_add_notifier(C, ND_KEYS, NULL);  // XXX
+	}
+	
+	return (success)? OPERATOR_FINISHED: OPERATOR_CANCELLED;
+}
+
+void ANIM_OT_remove_driver_button (wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name= "Remove Driver";
+	ot->idname= "ANIM_OT_remove_driver_button";
+	
+	/* callbacks */
+	ot->exec= remove_driver_button_exec; 
+	//op->poll= ???
+	
+	/* flags */
+	ot->flag= OPTYPE_REGISTER|OPTYPE_UNDO;
+
+	/* properties */
+	RNA_def_boolean(ot->srna, "all", 1, "All", "Delete keyfames from all elements of the array.");
+}
+
+/* ************************************************** */

source/blender/editors/animation/keyframing.c

@@ -825,7 +825,7 @@ short deletekey (ID *id, const char group[], const char rna_path[], int array_in
 	fcu= verify_fcurve(id, group, rna_path, array_index, 0);
 	adt= BKE_animdata_from_id(id);
 	
-	/* only continue if we have an ipo-curve to remove keyframes from */
+	/* only continue if we have an F-Curve to remove keyframes from */
 	if (adt && adt->action && fcu) {
 		bAction *act= adt->action;
 		short found = -1;

source/blender/editors/include/ED_keyframing.h

@@ -95,10 +95,25 @@ void ANIM_OT_delete_keyframe_menu(struct wmOperatorType *ot); // xxx unimplement
 void ANIM_OT_delete_keyframe_old(struct wmOperatorType *ot); // xxx rename and keep?
 
 /* Keyframe managment operators for UI buttons. */
-
 void ANIM_OT_insert_keyframe_button(struct wmOperatorType *ot);
 void ANIM_OT_delete_keyframe_button(struct wmOperatorType *ot);
 
+/* ************ Drivers ********************** */
+
+/* Main Driver Management API calls:
+ * 	Add a new driver for the specified property on the given ID block
+ */
+short ANIM_add_driver (struct ID *id, const char rna_path[], int array_index, short flag);
+
+/* Main Driver Management API calls:
+ * 	Remove the driver for the specified property on the given ID block (if available)
+ */
+short ANIM_remove_driver (struct ID *id, const char rna_path[], int array_index, short flag);
+
+/* Driver management operators for UI buttons */
+void ANIM_OT_add_driver_button(struct wmOperatorType *ot);
+void ANIM_OT_remove_driver_button(struct wmOperatorType *ot);
+
 /* ************ Auto-Keyframing ********************** */
 /* Notes:
  * - All the defines for this (User-Pref settings and Per-Scene settings)

source/blender/editors/include/UI_interface.h

@@ -133,6 +133,7 @@ typedef struct uiPopupBlockHandle uiPopupBlockHandle;
 #define UI_NO_HILITE		(1<<19)
 #define UI_BUT_ANIMATED		(1<<20)
 #define UI_BUT_ANIMATED_KEY	(1<<21)
+#define UI_BUT_DRIVEN		(1<<22)
 
 
 /* Button types, bits stored in 1 value... and a short even!

source/blender/editors/interface/interface_anim.c

@@ -27,28 +27,41 @@
 
 void ui_but_anim_flag(uiBut *but, float cfra)
 {
-	but->flag &= ~(UI_BUT_ANIMATED|UI_BUT_ANIMATED_KEY);
+	but->flag &= ~(UI_BUT_ANIMATED|UI_BUT_ANIMATED_KEY|UI_BUT_DRIVEN);
 
 	if(but->rnaprop && but->rnapoin.id.data) {
 		AnimData *adt= BKE_animdata_from_id(but->rnapoin.id.data);
 		FCurve *fcu;
 		char *path;
 
-		if(adt && adt->action && adt->action->curves.first) {
-			/* XXX this function call can become a performance bottleneck */
-			path= RNA_path_from_ID_to_property(&but->rnapoin, but->rnaprop);
-
-			if(path) {
-				fcu= list_find_fcurve(&adt->action->curves, path, but->rnaindex);
-
-				if(fcu) {
-					but->flag |= UI_BUT_ANIMATED;
-
-					if(on_keyframe_fcurve(fcu, cfra))
-						but->flag |= UI_BUT_ANIMATED_KEY;
+		if (adt) {
+			if ((adt->action && adt->action->curves.first) || (adt->drivers.first)) {
+				/* XXX this function call can become a performance bottleneck */
+				path= RNA_path_from_ID_to_property(&but->rnapoin, but->rnaprop);
+				
+				if (path) {
+					/* animation takes priority over drivers */
+					if (adt->action && adt->action->curves.first) {
+						fcu= list_find_fcurve(&adt->action->curves, path, but->rnaindex);
+						
+						if (fcu) {
+							but->flag |= UI_BUT_ANIMATED;
+							
+							if (on_keyframe_fcurve(fcu, cfra))
+								but->flag |= UI_BUT_ANIMATED_KEY;
+						}
+					}
+					
+					/* if not animated, check if driven */
+					if ((but->flag & UI_BUT_ANIMATED)==0 && (adt->drivers.first)) {
+						fcu= list_find_fcurve(&adt->drivers, path, but->rnaindex);
+						
+						if (fcu)
+							but->flag |= UI_BUT_DRIVEN;
+					}
+					
+					MEM_freeN(path);
 				}
-
-				MEM_freeN(path);
 			}
 		}
 	}
@@ -86,6 +99,19 @@ void ui_but_anim_delete_keyframe(bContext *C)
 	WM_operator_name_call(C, "ANIM_OT_delete_keyframe_button", WM_OP_INVOKE_DEFAULT, NULL);
 }
 
+void ui_but_anim_add_driver(bContext *C)
+{
+	/* this operator calls uiAnimContextProperty above */
+	WM_operator_name_call(C, "ANIM_OT_add_driver_button", WM_OP_INVOKE_DEFAULT, NULL);
+}
+
+void ui_but_anim_remove_driver(bContext *C)
+{
+	/* this operator calls uiAnimContextProperty above */
+	WM_operator_name_call(C, "ANIM_OT_remove_driver_button", WM_OP_INVOKE_DEFAULT, NULL);
+}
+
+// TODO: refine the logic for adding/removing drivers...
 void ui_but_anim_menu(bContext *C, uiBut *but)
 {
 	uiMenuItem *head;
@@ -100,18 +126,28 @@ void ui_but_anim_menu(bContext *C, uiBut *but)
 			if(length) {
 				uiMenuItemBooleanO(head, "Delete Keyframes", 0, "ANIM_OT_delete_keyframe_button", "all", 1);
 				uiMenuItemBooleanO(head, "Delete Single Keyframe", 0, "ANIM_OT_delete_keyframe_button", "all", 0);
+				
+				uiMenuItemBooleanO(head, "Remove Driver", 0, "ANIM_OT_remove_driver_button", "all", 1);
+				uiMenuItemBooleanO(head, "Remove Single Driver", 0, "ANIM_OT_remove_driver_button", "all", 0);
 			}
 			else {
 				uiMenuItemBooleanO(head, "Delete Keyframe", 0, "ANIM_OT_delete_keyframe_button", "all", 0);
+				
+				uiMenuItemBooleanO(head, "Remove Driver", 0, "ANIM_OT_remove_driver_button", "all", 0);
 			}
 		}
 		else if(RNA_property_animateable(&but->rnapoin, but->rnaprop)) {
 			if(length) {
 				uiMenuItemBooleanO(head, "Insert Keyframes", 0, "ANIM_OT_insert_keyframe_button", "all", 1);
 				uiMenuItemBooleanO(head, "Insert Single Keyframe", 0, "ANIM_OT_insert_keyframe_button", "all", 0);
+				
+				uiMenuItemBooleanO(head, "Add Driver", 0, "ANIM_OT_add_driver_button", "all", 1);
+				uiMenuItemBooleanO(head, "Add Single Driver", 0, "ANIM_OT_add_driver_button", "all", 0);
 			}
 			else {
 				uiMenuItemBooleanO(head, "Insert Keyframe", 0, "ANIM_OT_insert_keyframe_button", "all", 0);
+				
+				uiMenuItemBooleanO(head, "Add Driver", 0, "ANIM_OT_add_driver_button", "all", 0);
 			}
 		}
 

source/blender/editors/interface/interface_handlers.c

@@ -2610,6 +2610,17 @@ static int ui_do_button(bContext *C, uiBlock *block, uiBut *but, wmEvent *event)
 
 			return WM_UI_HANDLER_BREAK;
 		}
+		/* handle driver adding */
+		else if(event->type == DKEY && event->val == KM_PRESS) {
+			if(event->alt)
+				ui_but_anim_remove_driver(C);
+			else
+				ui_but_anim_add_driver(C);
+				
+			ED_region_tag_redraw(CTX_wm_region(C));
+			
+			return WM_UI_HANDLER_BREAK;
+		}
 		/* handle menu */
 		else if(event->type == RIGHTMOUSE && event->val == KM_PRESS) {
 			ui_but_anim_menu(C, but);

source/blender/editors/interface/interface_intern.h

@@ -393,6 +393,8 @@ void uiStyleExit(void);
 void ui_but_anim_flag(uiBut *but, float cfra);
 void ui_but_anim_insert_keyframe(struct bContext *C);
 void ui_but_anim_delete_keyframe(struct bContext *C);
+void ui_but_anim_add_driver(struct bContext *C);
+void ui_but_anim_remove_driver(struct bContext *C);
 void ui_but_anim_menu(struct bContext *C, uiBut *but);
 
 #endif

source/blender/editors/interface/interface_widgets.c

@@ -1053,6 +1053,8 @@ static void widget_state(uiWidgetType *wt, int state)
 			QUATCOPY(wt->wcol.inner, wt->wcol.inner_key_sel)
 		else if(state & UI_BUT_ANIMATED)
 			QUATCOPY(wt->wcol.inner, wt->wcol.inner_anim_sel)
+		//else if(state & UI_BUT_DRIVEN)
+		//	QUATCOPY(wt->wcol.inner, wt->wcol.inner_driven_sel)
 		else
 			QUATCOPY(wt->wcol.inner, wt->wcol.inner_sel)