Fix T40350: Some texture prop did not have visual feedback they were driven.

This is only a (hacky) partial fix, actually, since `RNA_property_animated()` will still
not work in those cases... Better that than nothing, though.

Thanks to Campbell for review.

6 files changed, 127 insertions, 83 deletions

diff --git a/source/blender/blenkernel/BKE_animsys.h b/source/blender/blenkernel/BKE_animsys.h
index 80d2750fe82..e79822daa4d 100644
--- a/source/blender/blenkernel/BKE_animsys.h
+++ b/source/blender/blenkernel/BKE_animsys.h
@@ -37,8 +37,10 @@ struct Main;
 struct AnimData;
 struct KeyingSet;
 struct KS_Path;
+struct bContext;
 
 struct PointerRNA;
+struct PropertyRNA;
 struct ReportList;
 struct bAction;
 struct bActionGroup;
@@ -127,6 +129,9 @@ void BKE_animdata_separate_by_basepath(struct ID *srcID, struct ID *dstID, struc
 /* Move F-Curves from src to destination if it's path is based on basepath */
 void action_move_fcurves_by_basepath(struct bAction *srcAct, struct bAction *dstAct, const char basepath[]);
 
+char *BKE_animdata_driver_path_hack(struct bContext *C, struct PointerRNA *ptr, struct PropertyRNA *prop,
+                                    char *base_path);
+
 /* ************************************* */
 /* Batch AnimData API */
 
diff --git a/source/blender/blenkernel/BKE_fcurve.h b/source/blender/blenkernel/BKE_fcurve.h
index 0e86be9b97c..c377769b271 100644
--- a/source/blender/blenkernel/BKE_fcurve.h
+++ b/source/blender/blenkernel/BKE_fcurve.h
@@ -43,6 +43,7 @@ struct DriverVar;
 struct DriverTarget;
 struct FCM_EnvelopeData;
 
+struct bContext;
 struct bAction;
 struct BezTriple;
 struct StructRNA;
@@ -221,8 +222,12 @@ struct FCurve *id_data_find_fcurve(ID *id, void *data, struct StructRNA *type, c
  */
 int list_find_data_fcurves(ListBase *dst, ListBase *src, const char *dataPrefix, const char *dataName);
 
-/* find an f-curve based on an rna property */
-struct FCurve *rna_get_fcurve(struct PointerRNA *ptr, struct PropertyRNA *prop, int rnaindex, struct bAction **action, bool *r_driven);
+/* find an f-curve based on an rna property. */
+struct FCurve *rna_get_fcurve(struct PointerRNA *ptr, struct PropertyRNA *prop, int rnaindex,
+                              struct bAction **action, bool *r_driven);
+/* Same as above, but takes a context data, temp hack needed for complex paths like texture ones. */
+struct FCurve *rna_get_fcurve_context_ui(struct bContext *C, struct PointerRNA *ptr, struct PropertyRNA *prop,
+                                         int rnaindex, struct bAction **action, bool *r_driven);
 
 /* Binary search algorithm for finding where to 'insert' BezTriple with given frame number.
  * Returns the index to insert at (data already at that index will be offset if replace is 0)
diff --git a/source/blender/blenkernel/intern/anim_sys.c b/source/blender/blenkernel/intern/anim_sys.c
index 5ee82bb5842..2fb832dc72d 100644
--- a/source/blender/blenkernel/intern/anim_sys.c
+++ b/source/blender/blenkernel/intern/anim_sys.c
@@ -51,18 +51,23 @@
 #include "DNA_material_types.h"
 #include "DNA_object_types.h"
 #include "DNA_scene_types.h"
+#include "DNA_screen_types.h"
+#include "DNA_space_types.h"
 #include "DNA_texture_types.h"
 #include "DNA_world_types.h"
 
 #include "BKE_animsys.h"
 #include "BKE_action.h"
+#include "BKE_context.h"
 #include "BKE_depsgraph.h"
 #include "BKE_fcurve.h"
 #include "BKE_nla.h"
 #include "BKE_global.h"
 #include "BKE_main.h"
+#include "BKE_material.h"
 #include "BKE_library.h"
 #include "BKE_report.h"
+#include "BKE_texture.h"
 
 #include "RNA_access.h"
 
@@ -551,6 +556,74 @@ void BKE_animdata_separate_by_basepath(ID *srcID, ID *dstID, ListBase *basepaths
 	}
 }
 
+/**
+ * Temporary wrapper for driver operators for buttons to make it easier to create
+ * such drivers by rerouting all paths through the active object instead so that
+ * they will get picked up by the dependency system.
+ *
+ * \param C Context pointer - for getting active data
+ * \param[in,out] ptr RNA pointer for property's datablock. May be modified as result of path remapping.
+ * \param prop RNA definition of property to add for
+ * \return MEM_alloc'd string representing the path to the property from the given #PointerRNA
+ */
+char *BKE_animdata_driver_path_hack(bContext *C, PointerRNA *ptr, PropertyRNA *prop, char *base_path)
+{
+	ID *id = (ID *)ptr->id.data;
+	ScrArea *sa = CTX_wm_area(C);
+
+	/* get standard path which may be extended */
+	char *basepath = base_path ? base_path : RNA_path_from_ID_to_property(ptr, prop);
+	char *path = basepath; /* in case no remapping is needed */
+
+	/* Remapping will only be performed in the Properties Editor, as only this
+	 * restricts the subspace of options to the 'active' data (a manageable state)
+	 */
+	/* TODO: watch out for pinned context? */
+	if ((sa) && (sa->spacetype == SPACE_BUTS)) {
+		Object *ob = CTX_data_active_object(C);
+
+		if (ob && id) {
+			/* only id-types which can be remapped to go through objects should be considered */
+			switch (GS(id->name)) {
+				case ID_TE: /* textures */
+				{
+					Material *ma = give_current_material(ob, ob->actcol);
+					Tex *tex = give_current_material_texture(ma);
+
+					/* assumes: texture will only be shown if it is active material's active texture it's ok */
+					if ((ID *)tex == id) {
+						char name_esc_ma[(sizeof(ma->id.name) - 2) * 2];
+						char name_esc_tex[(sizeof(tex->id.name) - 2) * 2];
+
+						BLI_strescape(name_esc_ma, ma->id.name + 2, sizeof(name_esc_ma));
+						BLI_strescape(name_esc_tex, tex->id.name + 2, sizeof(name_esc_tex));
+
+						/* create new path */
+						// TODO: use RNA path functions to construct step by step instead?
+						// FIXME: maybe this isn't even needed anymore...
+						path = BLI_sprintfN("material_slots[\"%s\"].material.texture_slots[\"%s\"].texture.%s",
+						                    name_esc_ma, name_esc_tex, basepath);
+
+						/* free old one */
+						if (basepath != base_path)
+							MEM_freeN(basepath);
+					}
+					break;
+				}
+			}
+
+			/* fix RNA pointer, as we've now changed the ID root by changing the paths */
+			if (basepath != path) {
+				/* rebase provided pointer so that it starts from object... */
+				RNA_pointer_create(&ob->id, ptr->type, ptr->data, ptr);
+			}
+		}
+	}
+
+	/* the path should now have been corrected for use */
+	return path;
+}
+
 /* Path Validation -------------------------------------------- */
 
 /* Check if a given RNA Path is valid, by tracing it from the given ID, and seeing if we can resolve it */
diff --git a/source/blender/blenkernel/intern/fcurve.c b/source/blender/blenkernel/intern/fcurve.c
index 09c1dcf701d..de6e6c53353 100644
--- a/source/blender/blenkernel/intern/fcurve.c
+++ b/source/blender/blenkernel/intern/fcurve.c
@@ -55,6 +55,7 @@
 #include "BKE_action.h"
 #include "BKE_armature.h"
 #include "BKE_constraint.h"
+#include "BKE_context.h"
 #include "BKE_curve.h" 
 #include "BKE_global.h"
 #include "BKE_object.h"
@@ -310,19 +311,35 @@ int list_find_data_fcurves(ListBase *dst, ListBase *src, const char *dataPrefix,
 
 FCurve *rna_get_fcurve(PointerRNA *ptr, PropertyRNA *prop, int rnaindex, bAction **action, bool *r_driven)
 {
+	return rna_get_fcurve_context_ui(NULL, ptr, prop, rnaindex, action, r_driven);
+}
+
+FCurve *rna_get_fcurve_context_ui(bContext *C, PointerRNA *ptr, PropertyRNA *prop, int rnaindex,
+                                  bAction **action, bool *r_driven)
+{
 	FCurve *fcu = NULL;
+	PointerRNA tptr = *ptr;
 	
 	*r_driven = false;
 	
 	/* there must be some RNA-pointer + property combon */
-	if (prop && ptr->id.data && RNA_property_animateable(ptr, prop)) {
-		AnimData *adt = BKE_animdata_from_id(ptr->id.data);
-		char *path;
+	if (prop && tptr.id.data && RNA_property_animateable(&tptr, prop)) {
+		AnimData *adt = BKE_animdata_from_id(tptr.id.data);
+		int step = 2;
+		char *path = NULL;
 		
-		if (adt) {
+		if (adt == NULL) {
+			path = BKE_animdata_driver_path_hack(C, &tptr, prop, NULL);
+			adt = BKE_animdata_from_id(tptr.id.data);
+			step--;
+		}
+		
+		while (adt && step--) {
 			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(ptr, prop);
+				if (step) {
+					path = RNA_path_from_ID_to_property(&tptr, prop);
+				}
 				
 				if (path) {
 					/* animation takes priority over drivers */
@@ -337,13 +354,25 @@ FCurve *rna_get_fcurve(PointerRNA *ptr, PropertyRNA *prop, int rnaindex, bAction
 							*r_driven = true;
 					}
 					
-					if (fcu && action)
+					if (fcu && action) {
 						*action = adt->action;
-					
-					MEM_freeN(path);
+						break;
+					}
+					else if (step) {
+						char *tpath = BKE_animdata_driver_path_hack(C, &tptr, prop, path);
+						if (tpath && tpath != path) {
+							MEM_freeN(path);
+							path = tpath;
+							adt = BKE_animdata_from_id(tptr.id.data);
+						}
+						else {
+							adt = NULL;
+						}
+					}
 				}
 			}
 		}
+		MEM_SAFE_FREE(path);
 	}
 	
 	return fcu;
diff --git a/source/blender/editors/animation/drivers.c b/source/blender/editors/animation/drivers.c
index 481912f4d1f..296a52e7f20 100644
--- a/source/blender/editors/animation/drivers.c
+++ b/source/blender/editors/animation/drivers.c
@@ -426,74 +426,6 @@ bool ANIM_paste_driver(ReportList *reports, ID *id, const char rna_path[], int a
 /* ************************************************** */
 /* UI-Button Interface */
 
-/**
- * Temporary wrapper for driver operators for buttons to make it easier to create
- * such drivers by rerouting all paths through the active object instead so that
- * they will get picked up by the dependency system.
- *
- * \param C Context pointer - for getting active data
- * \param[in,out] ptr RNA pointer for property's datablock. May be modified as result of path remapping.
- * \param prop RNA definition of property to add for
- * \return MEM_alloc'd string representing the path to the property from the given #PointerRNA
- */
-static char *get_driver_path_hack(bContext *C, PointerRNA *ptr, PropertyRNA *prop)
-{
-	ID *id = (ID *)ptr->id.data;
-	ScrArea *sa = CTX_wm_area(C);
-	
-	/* get standard path which may be extended */
-	char *basepath = RNA_path_from_ID_to_property(ptr, prop);
-	char *path = basepath; /* in case no remapping is needed */
-	
-	
-	/* Remapping will only be performed in the Properties Editor, as only this 
-	 * restricts the subspace of options to the 'active' data (a manageable state)
-	 */
-	// TODO: watch out for pinned context?
-	if ((sa) && (sa->spacetype == SPACE_BUTS)) {
-		Object *ob = CTX_data_active_object(C);
-		
-		if (ob && id) {
-			/* only id-types which can be remapped to go through objects should be considered */
-			switch (GS(id->name)) {
-				case ID_TE: /* textures */
-				{
-					Material *ma = give_current_material(ob, ob->actcol);
-					Tex *tex = give_current_material_texture(ma);
-					
-					/* assumes: texture will only be shown if it is active material's active texture it's ok */
-					if ((ID *)tex == id) {
-						char name_esc_ma[(sizeof(ma->id.name) - 2) * 2];
-						char name_esc_tex[(sizeof(tex->id.name) - 2) * 2];
-
-						BLI_strescape(name_esc_ma, ma->id.name + 2, sizeof(name_esc_ma));
-						BLI_strescape(name_esc_tex, tex->id.name + 2, sizeof(name_esc_tex));
-
-						/* create new path */
-						// TODO: use RNA path functions to construct step by step instead?
-						// FIXME: maybe this isn't even needed anymore...
-						path = BLI_sprintfN("material_slots[\"%s\"].material.texture_slots[\"%s\"].texture.%s", 
-						                    name_esc_ma, name_esc_tex, basepath);
-							
-						/* free old one */
-						MEM_freeN(basepath);
-					}
-					break;
-				}
-			}
-			
-			/* fix RNA pointer, as we've now changed the ID root by changing the paths */
-			if (basepath != path) {
-				/* rebase provided pointer so that it starts from object... */
-				RNA_pointer_create(&ob->id, ptr->type, ptr->data, ptr);
-			}
-		}
-	}
-	
-	/* the path should now have been corrected for use */
-	return path;
-}
-
 /* Add Driver Button Operator ------------------------ */
 
 static int add_driver_button_exec(bContext *C, wmOperator *op)
@@ -511,7 +443,7 @@ static int add_driver_button_exec(bContext *C, wmOperator *op)
 		index = -1;
 	
 	if (ptr.id.data && ptr.data && prop && RNA_property_animateable(&ptr, prop)) {
-		char *path = get_driver_path_hack(C, &ptr, prop);
+		char *path = BKE_animdata_driver_path_hack(C, &ptr, prop, NULL);
 		short flags = CREATEDRIVER_WITH_DEFAULT_DVAR;
 		
 		if (path) {
@@ -566,7 +498,7 @@ static int remove_driver_button_exec(bContext *C, wmOperator *op)
 		index = -1;
 	
 	if (ptr.id.data && ptr.data && prop) {
-		char *path = get_driver_path_hack(C, &ptr, prop);
+		char *path = BKE_animdata_driver_path_hack(C, &ptr, prop, NULL);
 		
 		success = ANIM_remove_driver(op->reports, ptr.id.data, path, index, 0);
 		MEM_freeN(path);
@@ -613,7 +545,7 @@ static int copy_driver_button_exec(bContext *C, wmOperator *op)
 	uiContextActiveProperty(C, &ptr, &prop, &index);
 	
 	if (ptr.id.data && ptr.data && prop && RNA_property_animateable(&ptr, prop)) {
-		char *path = get_driver_path_hack(C, &ptr, prop);
+		char *path = BKE_animdata_driver_path_hack(C, &ptr, prop, NULL);
 		
 		if (path) {
 			/* only copy the driver for the button that this was involved for */
@@ -657,7 +589,7 @@ static int paste_driver_button_exec(bContext *C, wmOperator *op)
 	uiContextActiveProperty(C, &ptr, &prop, &index);
 	
 	if (ptr.id.data && ptr.data && prop && RNA_property_animateable(&ptr, prop)) {
-		char *path = get_driver_path_hack(C, &ptr, prop);
+		char *path = BKE_animdata_driver_path_hack(C, &ptr, prop, NULL);
 		
 		if (path) {
 			/* only copy the driver for the button that this was involved for */
diff --git a/source/blender/editors/interface/interface_anim.c b/source/blender/editors/interface/interface_anim.c
index fa0832b6273..48e54270e95 100644
--- a/source/blender/editors/interface/interface_anim.c
+++ b/source/blender/editors/interface/interface_anim.c
@@ -61,7 +61,7 @@ static FCurve *ui_but_get_fcurve(uiBut *but, bAction **action, bool *r_driven)
 	 * but works well enough in typical cases */
 	int rnaindex = (but->rnaindex == -1) ? 0 : but->rnaindex;
 
-	return rna_get_fcurve(&but->rnapoin, but->rnaprop, rnaindex, action, r_driven);
+	return rna_get_fcurve_context_ui(but->block->evil_C, &but->rnapoin, but->rnaprop, rnaindex, action, r_driven);
 }
 
 void ui_but_anim_flag(uiBut *but, float cfra)