Code Cleanup: outliner used magic numbers for active items and selecting

Replace with enums to make it more obvious whats happening

3 files changed, 248 insertions, 148 deletions

diff --git a/source/blender/editors/space_outliner/outliner_draw.c b/source/blender/editors/space_outliner/outliner_draw.c
index 2f877e56f94..b5d4734ecf7 100644
--- a/source/blender/editors/space_outliner/outliner_draw.c
+++ b/source/blender/editors/space_outliner/outliner_draw.c
@@ -480,8 +480,8 @@ static void namebutton_cb(bContext *C, void *tsep, char *oldname)
 					Object *ob;
 					char newname[sizeof(bone->name)];
 					
-					// always make current object active
-					tree_element_active(C, scene, soops, te, 1); // was set_active_object()
+					/* always make current object active */
+					tree_element_active(C, scene, soops, te, OL_SETSEL_NORMAL);
 					ob = OBACT;
 					
 					/* restore bone name */
@@ -497,8 +497,8 @@ static void namebutton_cb(bContext *C, void *tsep, char *oldname)
 					Object *ob;
 					char newname[sizeof(pchan->name)];
 					
-					// always make current object active
-					tree_element_active(C, scene, soops, te, 1); // was set_active_object()
+					/* always make current pose-bone active */
+					tree_element_active(C, scene, soops, te, OL_SETSEL_NORMAL);
 					ob = OBACT;
 					
 					/* restore bone name */
@@ -1123,7 +1123,7 @@ static void outliner_draw_iconrow(bContext *C, uiBlock *block, Scene *scene, Spa
 {
 	TreeElement *te;
 	TreeStoreElem *tselem;
-	int active;
+	eOLDrawState active;
 
 	for (te = lb->first; te; te = te->next) {
 		
@@ -1139,20 +1139,20 @@ static void outliner_draw_iconrow(bContext *C, uiBlock *block, Scene *scene, Spa
 			/* active blocks get white circle */
 			if (tselem->type == 0) {
 				if (te->idcode == ID_OB) {
-					active = (OBACT == (Object *)tselem->id);
+					active = (OBACT == (Object *)tselem->id) ? OL_DRAWSEL_NORMAL : OL_DRAWSEL_NONE;
 				}
 				else if (scene->obedit && scene->obedit->data == tselem->id) {
-					active = 1;  // XXX use context?
+					active = OL_DRAWSEL_NORMAL;
 				}
 				else {
-					active = tree_element_active(C, scene, soops, te, 0);
+					active = tree_element_active(C, scene, soops, te, OL_SETSEL_NONE);
 				}
 			}
 			else {
-				active = tree_element_type_active(NULL, scene, soops, te, tselem, 0, false);
+				active = tree_element_type_active(NULL, scene, soops, te, tselem, OL_SETSEL_NONE, false);
 			}
 
-			if (active) {
+			if (active != OL_DRAWSEL_NONE) {
 				float ufac = UI_UNIT_X / 20.0f;
 
 				uiSetRoundBox(UI_CNR_ALL);
@@ -1202,7 +1202,8 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 	TreeElement *ten;
 	TreeStoreElem *tselem;
 	float ufac = UI_UNIT_X / 20.0f;
-	int offsx = 0, active = 0; // active=1 active obj, else active data
+	int offsx = 0;
+	eOLDrawState active = OL_DRAWSEL_NONE;
 	
 	tselem = TREESTORE(te);
 
@@ -1240,7 +1241,7 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 			if (te->idcode == ID_SCE) {
 				if (tselem->id == (ID *)scene) {
 					glColor4ub(255, 255, 255, alpha);
-					active = 2;
+					active = OL_DRAWSEL_ACTIVE;
 				}
 			}
 			else if (te->idcode == ID_GR) {
@@ -1251,7 +1252,7 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 					col[3] = alpha;
 					glColor4ubv((GLubyte *)col);
 					
-					active = 2;
+					active = OL_DRAWSEL_ACTIVE;
 				}
 			}
 			else if (te->idcode == ID_OB) {
@@ -1262,14 +1263,14 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 					
 					/* outliner active ob: always white text, circle color now similar to view3d */
 					
-					active = 2; /* means it draws a color circle */
+					active = OL_DRAWSEL_ACTIVE;
 					if (ob == OBACT) {
 						if (ob->flag & SELECT) {
 							UI_GetThemeColorType4ubv(TH_ACTIVE, SPACE_VIEW3D, col);
 							col[3] = alpha;
 						}
 						
-						active = 1; /* means it draws white text */
+						active = OL_DRAWSEL_NORMAL;
 					}
 					else if (ob->flag & SELECT) {
 						UI_GetThemeColorType4ubv(TH_SELECT, SPACE_VIEW3D, col);
@@ -1282,22 +1283,24 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 			}
 			else if (scene->obedit && scene->obedit->data == tselem->id) {
 				glColor4ub(255, 255, 255, alpha);
-				active = 2;
+				active = OL_DRAWSEL_ACTIVE;
 			}
 			else {
-				if (tree_element_active(C, scene, soops, te, 0)) {
+				if (tree_element_active(C, scene, soops, te, OL_SETSEL_NONE)) {
 					glColor4ub(220, 220, 255, alpha);
-					active = 2;
+					active = OL_DRAWSEL_ACTIVE;
 				}
 			}
 		}
 		else {
-			if (tree_element_type_active(NULL, scene, soops, te, tselem, 0, false)) active = 2;
+			if (tree_element_type_active(NULL, scene, soops, te, tselem, OL_SETSEL_NONE, false) != OL_DRAWSEL_NONE) {
+				active = OL_DRAWSEL_ACTIVE;
+			}
 			glColor4ub(220, 220, 255, alpha);
 		}
 		
 		/* active circle */
-		if (active) {
+		if (active != OL_DRAWSEL_NONE) {
 			uiSetRoundBox(UI_CNR_ALL);
 			uiRoundBox((float)startx + UI_UNIT_X,
 			           (float)*starty + 1.0f * ufac,
@@ -1348,7 +1351,7 @@ static void outliner_draw_tree_element(bContext *C, uiBlock *block, Scene *scene
 		glDisable(GL_BLEND);
 		
 		/* name */
-		if (active == 1) UI_ThemeColor(TH_TEXT_HI);
+		if (active == OL_DRAWSEL_NORMAL) UI_ThemeColor(TH_TEXT_HI);
 		else if (ELEM(tselem->type, TSE_RNA_PROPERTY, TSE_RNA_ARRAY_ELEM)) UI_ThemeColorBlend(TH_BACK, TH_TEXT, 0.75f);
 		else UI_ThemeColor(TH_TEXT);
 		
diff --git a/source/blender/editors/space_outliner/outliner_intern.h b/source/blender/editors/space_outliner/outliner_intern.h
index 015d8d64627..34d7f87e44d 100644
--- a/source/blender/editors/space_outliner/outliner_intern.h
+++ b/source/blender/editors/space_outliner/outliner_intern.h
@@ -108,6 +108,18 @@ typedef struct TreeElement {
 /* button events */
 #define OL_NAMEBUTTON       1
 
+typedef enum {
+	OL_DRAWSEL_NONE    = 0,  /* inactive (regular black text) */
+	OL_DRAWSEL_NORMAL  = 1,  /* active object (draws white text) */
+	OL_DRAWSEL_ACTIVE  = 2,  /* active obdata (draws a circle around the icon) */
+} eOLDrawState;
+
+typedef enum {
+	OL_SETSEL_NONE     = 0,  /* don't change the selection state */
+	OL_SETSEL_NORMAL   = 1,  /* select the item */
+	OL_SETSEL_EXTEND   = 2,  /* select the item and extend (also toggles selection) */
+} eOLSetState;
+
 /* get TreeStoreElem associated with a TreeElement 
  * < a: (TreeElement) tree element to find stored element for
  */
@@ -166,8 +178,12 @@ void draw_outliner(const struct bContext *C);
 void restrictbutton_gr_restrict_flag(void *poin, void *poin2, int flag);
 
 /* outliner_select.c -------------------------------------------- */
-int tree_element_type_active(struct bContext *C, struct Scene *scene, struct SpaceOops *soops, TreeElement *te, TreeStoreElem *tselem, int set, bool recursive);
-int tree_element_active(struct bContext *C, struct Scene *scene, SpaceOops *soops, TreeElement *te, int set);
+eOLDrawState tree_element_type_active(
+        struct bContext *C, struct Scene *scene, struct SpaceOops *soops,
+        TreeElement *te, TreeStoreElem *tselem, const eOLSetState set, bool recursive);
+eOLDrawState tree_element_active(
+        struct bContext *C, struct Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set);
 int outliner_item_do_activate(struct bContext *C, int x, int y, bool extend, bool recursive);
 
 /* outliner_edit.c ---------------------------------------------- */
@@ -177,7 +193,7 @@ void outliner_do_object_operation(struct bContext *C, struct Scene *scene, struc
 
 int common_restrict_check(struct bContext *C, struct Object *ob);
 
-bool outliner_has_one_flag(struct SpaceOops *soops, ListBase *lb, short flag, const int curlevel);
+int outliner_has_one_flag(struct SpaceOops *soops, ListBase *lb, short flag, const int curlevel);
 void outliner_set_flag(struct SpaceOops *soops, ListBase *lb, short flag, short set);
 
 void object_toggle_visibility_cb(struct bContext *C, struct Scene *scene, TreeElement *te, struct TreeStoreElem *tsep, struct TreeStoreElem *tselem);
diff --git a/source/blender/editors/space_outliner/outliner_select.c b/source/blender/editors/space_outliner/outliner_select.c
index b10b8a46ec6..688695e3ded 100644
--- a/source/blender/editors/space_outliner/outliner_select.c
+++ b/source/blender/editors/space_outliner/outliner_select.c
@@ -124,23 +124,24 @@ static int outliner_select(SpaceOops *soops, ListBase *lb, int *index, short *se
 /* ****************************************************** */
 /* Outliner Element Selection/Activation on Click */
 
-static int tree_element_active_renderlayer(bContext *C, TreeElement *te, TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_renderlayer(
+        bContext *C, TreeElement *te, TreeStoreElem *tselem, const eOLSetState set)
 {
 	Scene *sce;
 	
 	/* paranoia check */
 	if (te->idcode != ID_SCE)
-		return 0;
+		return OL_DRAWSEL_NONE;
 	sce = (Scene *)tselem->id;
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		sce->r.actlay = tselem->nr;
 		WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, sce);
 	}
 	else {
 		return sce->r.actlay == tselem->nr;
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
 /**
@@ -185,8 +186,9 @@ static void do_outliner_ebone_select_recursive(bArmature *arm, EditBone *ebone_p
 	}
 }
 
-static int  tree_element_set_active_object(bContext *C, Scene *scene, SpaceOops *soops,
-                                           TreeElement *te, int set, bool recursive)
+static eOLDrawState tree_element_set_active_object(
+        bContext *C, Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set, bool recursive)
 {
 	TreeStoreElem *tselem = TREESTORE(te);
 	Scene *sce;
@@ -199,9 +201,13 @@ static int  tree_element_set_active_object(bContext *C, Scene *scene, SpaceOops
 	}
 	else {
 		ob = (Object *)outliner_search_back(soops, te, ID_OB);
-		if (ob == OBACT) return 0;
+		if (ob == OBACT) {
+			return OL_DRAWSEL_NONE;
+		}
+	}
+	if (ob == NULL) {
+		return OL_DRAWSEL_NONE;
 	}
-	if (ob == NULL) return 0;
 	
 	sce = (Scene *)outliner_search_back(soops, te, ID_SCE);
 	if (sce && scene != sce) {
@@ -213,7 +219,7 @@ static int  tree_element_set_active_object(bContext *C, Scene *scene, SpaceOops
 	base = BKE_scene_base_find(scene, ob);
 
 	if (base) {
-		if (set == 2) {
+		if (set == OL_SETSEL_EXTEND) {
 			/* swap select */
 			if (base->flag & SELECT)
 				ED_base_object_select(base, BA_DESELECT);
@@ -240,10 +246,12 @@ static int  tree_element_set_active_object(bContext *C, Scene *scene, SpaceOops
 	if (ob != scene->obedit)
 		ED_object_editmode_exit(C, EM_FREEDATA | EM_FREEUNDO | EM_WAITCURSOR | EM_DO_UNDO);
 		
-	return 1;
+	return OL_DRAWSEL_NORMAL;
 }
 
-static int tree_element_active_material(bContext *C, Scene *scene, SpaceOops *soops, TreeElement *te, int set)
+static eOLDrawState tree_element_active_material(
+        bContext *C, Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set)
 {
 	TreeElement *tes;
 	Object *ob;
@@ -251,45 +259,58 @@ static int tree_element_active_material(bContext *C, Scene *scene, SpaceOops *so
 	/* we search for the object parent */
 	ob = (Object *)outliner_search_back(soops, te, ID_OB);
 	// note: ob->matbits can be NULL when a local object points to a library mesh.
-	if (ob == NULL || ob != OBACT || ob->matbits == NULL) return 0;  // just paranoia
+	if (ob == NULL || ob != OBACT || ob->matbits == NULL) {
+		return OL_DRAWSEL_NONE;  /* just paranoia */
+	}
 	
 	/* searching in ob mat array? */
 	tes = te->parent;
 	if (tes->idcode == ID_OB) {
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 			ob->actcol = te->index + 1;
 			ob->matbits[te->index] = 1;  // make ob material active too
 		}
 		else {
-			if (ob->actcol == te->index + 1)
-				if (ob->matbits[te->index]) return 1;
+			if (ob->actcol == te->index + 1) {
+				if (ob->matbits[te->index]) {
+					return OL_DRAWSEL_NORMAL;
+				}
+			}
 		}
 	}
 	/* or we search for obdata material */
 	else {
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 			ob->actcol = te->index + 1;
 			ob->matbits[te->index] = 0;  // make obdata material active too
 		}
 		else {
-			if (ob->actcol == te->index + 1)
-				if (ob->matbits[te->index] == 0) return 1;
+			if (ob->actcol == te->index + 1) {
+				if (ob->matbits[te->index] == 0) {
+					return OL_DRAWSEL_NORMAL;
+				}
+			}
 		}
 	}
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		WM_event_add_notifier(C, NC_MATERIAL | ND_SHADING_LINKS, NULL);
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_texture(bContext *C, Scene *scene, SpaceOops *UNUSED(soops), TreeElement *te, int set)
+static eOLDrawState tree_element_active_texture(
+        bContext *C, Scene *scene, SpaceOops *UNUSED(soops),
+        TreeElement *te, const eOLSetState set)
 {
 	TreeElement *tep;
 	TreeStoreElem /* *tselem,*/ *tselemp;
 	Object *ob = OBACT;
 	SpaceButs *sbuts = NULL;
 	
-	if (ob == NULL) return 0;  // no active object
+	if (ob == NULL) {
+		/* no active object */
+		return OL_DRAWSEL_NONE;
+	}
 	
 	/*tselem = TREESTORE(te);*/ /*UNUSED*/
 	
@@ -303,7 +324,7 @@ static int tree_element_active_texture(bContext *C, Scene *scene, SpaceOops *UNU
 	if (tep->idcode == ID_WO) {
 		World *wrld = (World *)tselemp->id;
 
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 			if (sbuts) {
 				// XXX sbuts->tabo = TAB_SHADING_TEX;	// hack from header_buttonswin.c
 				// XXX sbuts->texfrom = 1;
@@ -312,12 +333,14 @@ static int tree_element_active_texture(bContext *C, Scene *scene, SpaceOops *UNU
 			wrld->texact = te->index;
 		}
 		else if (tselemp->id == (ID *)(scene->world)) {
-			if (wrld->texact == te->index) return 1;
+			if (wrld->texact == te->index) {
+				return OL_DRAWSEL_NORMAL;
+			}
 		}
 	}
 	else if (tep->idcode == ID_LA) {
 		Lamp *la = (Lamp *)tselemp->id;
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 			if (sbuts) {
 				// XXX sbuts->tabo = TAB_SHADING_TEX;	// hack from header_buttonswin.c
 				// XXX sbuts->texfrom = 2;
@@ -327,13 +350,15 @@ static int tree_element_active_texture(bContext *C, Scene *scene, SpaceOops *UNU
 		}
 		else {
 			if (tselemp->id == ob->data) {
-				if (la->texact == te->index) return 1;
+				if (la->texact == te->index) {
+					return OL_DRAWSEL_NORMAL;
+				}
 			}
 		}
 	}
 	else if (tep->idcode == ID_MA) {
 		Material *ma = (Material *)tselemp->id;
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 			if (sbuts) {
 				//sbuts->tabo = TAB_SHADING_TEX;	// hack from header_buttonswin.c
 				// XXX sbuts->texfrom = 0;
@@ -345,46 +370,60 @@ static int tree_element_active_texture(bContext *C, Scene *scene, SpaceOops *UNU
 			ob->actcol = tep->index + 1;
 		}
 		else if (tep->flag & TE_ACTIVE) {   // this is active material
-			if (ma->texact == te->index) return 1;
+			if (ma->texact == te->index) {
+				return OL_DRAWSEL_NORMAL;
+			}
 		}
 	}
 	
-	if (set)
+	if (set != OL_SETSEL_NONE) {
 		WM_event_add_notifier(C, NC_TEXTURE, NULL);
+	}
 
-	return 0;
+	/* no active object */
+	return OL_DRAWSEL_NONE;
 }
 
 
-static int tree_element_active_lamp(bContext *UNUSED(C), Scene *scene, SpaceOops *soops, TreeElement *te, int set)
+static eOLDrawState tree_element_active_lamp(
+        bContext *UNUSED(C), Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set)
 {
 	Object *ob;
 	
 	/* we search for the object parent */
 	ob = (Object *)outliner_search_back(soops, te, ID_OB);
-	if (ob == NULL || ob != OBACT) return 0;  // just paranoia
+	if (ob == NULL || ob != OBACT) {
+		/* just paranoia */
+		return OL_DRAWSEL_NONE;
+	}
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 // XXX		extern_set_butspace(F5KEY, 0);
 	}
 	else {
-		return 1;
+		return OL_DRAWSEL_NORMAL;
 	}
 	
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_camera(bContext *UNUSED(C), Scene *scene, SpaceOops *soops, TreeElement *te, int set)
+static eOLDrawState tree_element_active_camera(
+        bContext *UNUSED(C), Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set)
 {
 	Object *ob = (Object *)outliner_search_back(soops, te, ID_OB);
 
-	if (set)
-		return 0;
+	if (set != OL_SETSEL_NONE) {
+		return OL_DRAWSEL_NONE;
+	}
 
 	return scene->camera == ob;
 }
 
-static int tree_element_active_world(bContext *C, Scene *scene, SpaceOops *UNUSED(soops), TreeElement *te, int set)
+static eOLDrawState tree_element_active_world(
+        bContext *C, Scene *scene, SpaceOops *UNUSED(soops),
+        TreeElement *te, const eOLSetState set)
 {
 	TreeElement *tep;
 	TreeStoreElem *tselem = NULL;
@@ -397,30 +436,32 @@ static int tree_element_active_world(bContext *C, Scene *scene, SpaceOops *UNUSE
 			sce = (Scene *)tselem->id;
 	}
 	
-	if (set) {  // make new scene active
+	if (set != OL_SETSEL_NONE) {
+		/* make new scene active */
 		if (sce && scene != sce) {
 			ED_screen_set_scene(C, CTX_wm_screen(C), sce);
 		}
 	}
 	
 	if (tep == NULL || tselem->id == (ID *)scene) {
-		if (set) {
+		if (set != OL_SETSEL_NONE) {
 // XXX			extern_set_butspace(F8KEY, 0);
 		}
 		else {
-			return 1;
+			return OL_DRAWSEL_NORMAL;
 		}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_defgroup(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_defgroup(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, const eOLSetState set)
 {
 	Object *ob;
 	
 	/* id in tselem is object */
 	ob = (Object *)tselem->id;
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		BLI_assert(te->index + 1 >= 0);
 		ob->actdef = te->index + 1;
 
@@ -429,16 +470,19 @@ static int tree_element_active_defgroup(bContext *C, Scene *scene, TreeElement *
 	}
 	else {
 		if (ob == OBACT)
-			if (ob->actdef == te->index + 1) return 1;
+			if (ob->actdef == te->index + 1) {
+				return OL_DRAWSEL_NORMAL;
+			}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_posegroup(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_posegroup(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, const eOLSetState set)
 {
 	Object *ob = (Object *)tselem->id;
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		if (ob->pose) {
 			ob->pose->active_group = te->index + 1;
 			WM_event_add_notifier(C, NC_OBJECT | ND_DRAW, ob);
@@ -446,29 +490,32 @@ static int tree_element_active_posegroup(bContext *C, Scene *scene, TreeElement
 	}
 	else {
 		if (ob == OBACT && ob->pose) {
-			if (ob->pose->active_group == te->index + 1) return 1;
+			if (ob->pose->active_group == te->index + 1) {
+				return OL_DRAWSEL_NORMAL;
+			}
 		}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_posechannel(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, int set, bool recursive)
+static eOLDrawState tree_element_active_posechannel(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, const eOLSetState set, bool recursive)
 {
 	Object *ob = (Object *)tselem->id;
 	bArmature *arm = ob->data;
 	bPoseChannel *pchan = te->directdata;
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		if (!(pchan->bone->flag & BONE_HIDDEN_P)) {
 			
-			if (set != 2) {
+			if (set != OL_SETSEL_EXTEND) {
 				bPoseChannel *pchannel;
 				/* single select forces all other bones to get unselected */
 				for (pchannel = ob->pose->chanbase.first; pchannel; pchannel = pchannel->next)
 					pchannel->bone->flag &= ~(BONE_TIPSEL | BONE_SELECTED | BONE_ROOTSEL);
 			}
 
-			if (set == 2 && (pchan->bone->flag & BONE_SELECTED)) {
+			if ((set == OL_SETSEL_EXTEND) && (pchan->bone->flag & BONE_SELECTED)) {
 				pchan->bone->flag &= ~BONE_SELECTED;
 			}
 			else {
@@ -487,22 +534,25 @@ static int tree_element_active_posechannel(bContext *C, Scene *scene, TreeElemen
 	}
 	else {
 		if (ob == OBACT && ob->pose) {
-			if (pchan->bone->flag & BONE_SELECTED) return 1;
+			if (pchan->bone->flag & BONE_SELECTED) {
+				return OL_DRAWSEL_NORMAL;
+			}
 		}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_bone(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, int set, bool recursive)
+static eOLDrawState tree_element_active_bone(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *tselem, const eOLSetState set, bool recursive)
 {
 	bArmature *arm = (bArmature *)tselem->id;
 	Bone *bone = te->directdata;
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		if (!(bone->flag & BONE_HIDDEN_P)) {
 			Object *ob = OBACT;
 			if (ob) {
-				if (set != 2) {
+				if (set != OL_SETSEL_EXTEND) {
 					bPoseChannel *pchannel;
 					/* single select forces all other bones to get unselected */
 					for (pchannel = ob->pose->chanbase.first; pchannel; pchannel = pchannel->next)
@@ -510,7 +560,7 @@ static int tree_element_active_bone(bContext *C, Scene *scene, TreeElement *te,
 				}
 			}
 			
-			if (set == 2 && (bone->flag & BONE_SELECTED)) {
+			if (set == OL_SETSEL_EXTEND && (bone->flag & BONE_SELECTED)) {
 				bone->flag &= ~BONE_SELECTED;
 			}
 			else {
@@ -531,10 +581,12 @@ static int tree_element_active_bone(bContext *C, Scene *scene, TreeElement *te,
 		Object *ob = OBACT;
 		
 		if (ob && ob->data == arm) {
-			if (bone->flag & BONE_SELECTED) return 1;
+			if (bone->flag & BONE_SELECTED) {
+				return OL_DRAWSEL_NORMAL;
+			}
 		}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
 
@@ -555,29 +607,31 @@ static void tree_element_active_ebone__sel(bContext *C, Scene *scene, bArmature
 
 	WM_event_add_notifier(C, NC_OBJECT | ND_BONE_ACTIVE, scene->obedit);
 }
-static int tree_element_active_ebone(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), int set, bool recursive)
+static eOLDrawState tree_element_active_ebone(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), const eOLSetState set, bool recursive)
 {
 	bArmature *arm = scene->obedit->data;
 	EditBone *ebone = te->directdata;
-	int status = 0;
-	if (set) {
-		if (set == 1) {
+	eOLDrawState status = OL_DRAWSEL_NONE;
+
+	if (set != OL_SETSEL_NONE) {
+		if (set == OL_SETSEL_NORMAL) {
 			if (!(ebone->flag & BONE_HIDDEN_A)) {
 				ED_armature_deselect_all(scene->obedit, 0); // deselect
 				tree_element_active_ebone__sel(C, scene, arm, ebone, TRUE);
-				status = 1;
+				status = OL_DRAWSEL_NORMAL;
 			}
 		}
-		else if (set == 2) {
+		else if (set == OL_SETSEL_EXTEND) {
 			if (!(ebone->flag & BONE_HIDDEN_A)) {
 				if (!(ebone->flag & BONE_SELECTED)) {
 					tree_element_active_ebone__sel(C, scene, arm, ebone, TRUE);
-					status = 1;
+					status = OL_DRAWSEL_NORMAL;
 				}
 				else {
 					/* entirely selected, so de-select */
 					tree_element_active_ebone__sel(C, scene, arm, ebone, FALSE);
-					status = 0;
+					status = OL_DRAWSEL_NONE;
 				}
 			}
 		}
@@ -588,14 +642,16 @@ static int tree_element_active_ebone(bContext *C, Scene *scene, TreeElement *te,
 		}
 	}
 	else if (ebone->flag & BONE_SELECTED) {
-		status = 1;
+		status = OL_DRAWSEL_NORMAL;
 	}
+
 	return status;
 }
 
-static int tree_element_active_modifier(bContext *C, TreeElement *UNUSED(te), TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_modifier(
+        bContext *C, TreeElement *UNUSED(te), TreeStoreElem *tselem, const eOLSetState set)
 {
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		Object *ob = (Object *)tselem->id;
 		
 		WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
@@ -603,12 +659,13 @@ static int tree_element_active_modifier(bContext *C, TreeElement *UNUSED(te), Tr
 // XXX		extern_set_butspace(F9KEY, 0);
 	}
 	
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_psys(bContext *C, Scene *UNUSED(scene), TreeElement *UNUSED(te), TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_psys(
+        bContext *C, Scene *UNUSED(scene), TreeElement *UNUSED(te), TreeStoreElem *tselem, const eOLSetState set)
 {
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		Object *ob = (Object *)tselem->id;
 		
 		WM_event_add_notifier(C, NC_OBJECT | ND_PARTICLE | NA_EDITED, ob);
@@ -616,33 +673,37 @@ static int tree_element_active_psys(bContext *C, Scene *UNUSED(scene), TreeEleme
 // XXX		extern_set_butspace(F7KEY, 0);
 	}
 	
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_constraint(bContext *C, TreeElement *UNUSED(te), TreeStoreElem *tselem, int set)
+static int tree_element_active_constraint(
+        bContext *C, TreeElement *UNUSED(te), TreeStoreElem *tselem, const eOLSetState set)
 {
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		Object *ob = (Object *)tselem->id;
 		
 		WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
 // XXX		extern_set_butspace(F7KEY, 0);
 	}
 	
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_text(bContext *UNUSED(C), Scene *UNUSED(scene), SpaceOops *UNUSED(soops), TreeElement *UNUSED(te), int UNUSED(set))
+static eOLDrawState tree_element_active_text(
+        bContext *UNUSED(C), Scene *UNUSED(scene), SpaceOops *UNUSED(soops),
+        TreeElement *UNUSED(te), int UNUSED(set))
 {
 	// XXX removed
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_pose(bContext *C, Scene *scene, TreeElement *UNUSED(te), TreeStoreElem *tselem, int set)
+static eOLDrawState tree_element_active_pose(
+        bContext *C, Scene *scene, TreeElement *UNUSED(te), TreeStoreElem *tselem, const eOLSetState set)
 {
 	Object *ob = (Object *)tselem->id;
 	Base *base = BKE_scene_base_find(scene, ob);
 	
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		if (scene->obedit)
 			ED_object_editmode_exit(C, EM_FREEDATA | EM_FREEUNDO | EM_WAITCURSOR | EM_DO_UNDO);
 		
@@ -652,25 +713,28 @@ static int tree_element_active_pose(bContext *C, Scene *scene, TreeElement *UNUS
 			ED_armature_enter_posemode(C, base);
 	}
 	else {
-		if (ob->mode & OB_MODE_POSE) return 1;
+		if (ob->mode & OB_MODE_POSE) {
+			return OL_DRAWSEL_NORMAL;
+		}
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_sequence(bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), int set)
+static eOLDrawState tree_element_active_sequence(
+        bContext *C, Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), const eOLSetState set)
 {
 	Sequence *seq = (Sequence *) te->directdata;
 	Editing *ed = BKE_sequencer_editing_get(scene, FALSE);
 
-	if (set) {
+	if (set != OL_SETSEL_NONE) {
 		/* only check on setting */
 		if (BLI_findindex(ed->seqbasep, seq) != -1) {
-			if (set == 2) {
+			if (set == OL_SETSEL_EXTEND) {
 				BKE_sequencer_active_set(scene, NULL);
 			}
 			ED_sequencer_deselect_all(scene);
 
-			if (set == 2 && seq->flag & SELECT) {
+			if ((set == OL_SETSEL_EXTEND) && seq->flag & SELECT) {
 				seq->flag &= ~SELECT;
 			}
 			else {
@@ -683,22 +747,23 @@ static int tree_element_active_sequence(bContext *C, Scene *scene, TreeElement *
 	}
 	else {
 		if (ed->act_seq == seq && seq->flag & SELECT) {
-			return 1;
+			return OL_DRAWSEL_NORMAL;
 		}
 	}
-	return(0);
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_sequence_dup(Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), int set)
+static eOLDrawState tree_element_active_sequence_dup(
+        Scene *scene, TreeElement *te, TreeStoreElem *UNUSED(tselem), const eOLSetState set)
 {
 	Sequence *seq, *p;
 	Editing *ed = BKE_sequencer_editing_get(scene, FALSE);
 
 	seq = (Sequence *)te->directdata;
-	if (set == 0) {
+	if (set == OL_SETSEL_NONE) {
 		if (seq->flag & SELECT)
-			return(1);
-		return(0);
+			return OL_DRAWSEL_NORMAL;
+		return OL_DRAWSEL_NONE;
 	}
 
 // XXX	select_single_seq(seq, 1);
@@ -713,27 +778,32 @@ static int tree_element_active_sequence_dup(Scene *scene, TreeElement *te, TreeS
 // XXX			select_single_seq(p, 0);
 		p = p->next;
 	}
-	return(0);
+	return OL_DRAWSEL_NONE;
 }
 
-static int tree_element_active_keymap_item(bContext *UNUSED(C), TreeElement *te, TreeStoreElem *UNUSED(tselem), int set)
+static eOLDrawState tree_element_active_keymap_item(
+        bContext *UNUSED(C), TreeElement *te, TreeStoreElem *UNUSED(tselem), const eOLSetState set)
 {
 	wmKeyMapItem *kmi = te->directdata;
 	
-	if (set == 0) {
-		if (kmi->flag & KMI_INACTIVE) return 0;
-		return 1;
+	if (set == OL_SETSEL_NONE) {
+		if (kmi->flag & KMI_INACTIVE) {
+			return OL_DRAWSEL_NONE;
+		}
+		return OL_DRAWSEL_NORMAL;
 	}
 	else {
 		kmi->flag ^= KMI_INACTIVE;
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
 /* ---------------------------------------------- */
 
 /* generic call for ID data check or make/check active in UI */
-int tree_element_active(bContext *C, Scene *scene, SpaceOops *soops, TreeElement *te, int set)
+eOLDrawState tree_element_active(
+        bContext *C, Scene *scene, SpaceOops *soops,
+        TreeElement *te, const eOLSetState set)
 {
 
 	switch (te->idcode) {
@@ -752,13 +822,17 @@ int tree_element_active(bContext *C, Scene *scene, SpaceOops *soops, TreeElement
 		case ID_CA:
 			return tree_element_active_camera(C, scene, soops, te, set);
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
-/* generic call for non-id data to make/check active in UI */
-/* Context can be NULL when set==0 */
-int tree_element_type_active(bContext *C, Scene *scene, SpaceOops *soops,
-                             TreeElement *te, TreeStoreElem *tselem, int set, bool recursive)
+/**
+ * Generic call for non-id data to make/check active in UI
+ *
+ * \note Context can be NULL when ``(set == OL_SETSEL_NONE)``
+ */
+eOLDrawState tree_element_type_active(
+        bContext *C, Scene *scene, SpaceOops *soops,
+        TreeElement *te, TreeStoreElem *tselem, const eOLSetState set, bool recursive)
 {
 	switch (tselem->type) {
 		case TSE_DEFGROUP:
@@ -770,8 +844,12 @@ int tree_element_type_active(bContext *C, Scene *scene, SpaceOops *soops,
 		case TSE_MODIFIER:
 			return tree_element_active_modifier(C, te, tselem, set);
 		case TSE_LINKED_OB:
-			if (set) tree_element_set_active_object(C, scene, soops, te, set, FALSE);
-			else if (tselem->id == (ID *)OBACT) return 1;
+			if (set != OL_SETSEL_NONE) {
+				tree_element_set_active_object(C, scene, soops, te, set, false);
+			}
+			else if (tselem->id == (ID *)OBACT) {
+				return OL_DRAWSEL_NORMAL;
+			}
 			break;
 		case TSE_LINKED_PSYS:
 			return tree_element_active_psys(C, scene, te, tselem, set);
@@ -793,23 +871,23 @@ int tree_element_type_active(bContext *C, Scene *scene, SpaceOops *soops,
 			return tree_element_active_keymap_item(C, te, tselem, set);
 			
 	}
-	return 0;
+	return OL_DRAWSEL_NONE;
 }
 
 /* ================================================ */
 
-static int do_outliner_item_activate(bContext *C, Scene *scene, ARegion *ar, SpaceOops *soops,
-                                     TreeElement *te, bool extend, bool recursive, const float mval[2])
+static bool do_outliner_item_activate(bContext *C, Scene *scene, ARegion *ar, SpaceOops *soops,
+                                      TreeElement *te, bool extend, bool recursive, const float mval[2])
 {
 	
 	if (mval[1] > te->ys && mval[1] < te->ys + UI_UNIT_Y) {
 		TreeStoreElem *tselem = TREESTORE(te);
-		int openclose = 0;
+		bool openclose = false;
 		
 		/* open close icon */
 		if ((te->flag & TE_ICONROW) == 0) {               // hidden icon, no open/close
 			if (mval[0] > te->xs && mval[0] < te->xs + UI_UNIT_X)
-				openclose = 1;
+				openclose = true;
 		}
 		
 		if (openclose) {
@@ -824,7 +902,7 @@ static int do_outliner_item_activate(bContext *C, Scene *scene, ARegion *ar, Spa
 				
 			}
 			
-			return 1;
+			return true;
 		}
 		/* name and first icon */
 		else if (mval[0] > te->xs + UI_UNIT_X && mval[0] < te->xend) {
@@ -832,7 +910,7 @@ static int do_outliner_item_activate(bContext *C, Scene *scene, ARegion *ar, Spa
 			/* always makes active object */
 			if (tselem->type != TSE_SEQUENCE && tselem->type != TSE_SEQ_STRIP && tselem->type != TSE_SEQUENCE_DUP)
 				tree_element_set_active_object(C, scene, soops, te,
-				                               1 + (extend != 0 && tselem->type == 0),
+				                               (extend && tselem->type == 0) ? OL_SETSEL_EXTEND : OL_SETSEL_NORMAL,
 				                               recursive && tselem->type == 0 );
 			
 			if (tselem->type == 0) { // the lib blocks
@@ -874,22 +952,26 @@ static int do_outliner_item_activate(bContext *C, Scene *scene, ARegion *ar, Spa
 					WM_operator_name_call(C, "OBJECT_OT_editmode_toggle", WM_OP_INVOKE_REGION_WIN, NULL);
 				}
 				else {  // rest of types
-					tree_element_active(C, scene, soops, te, 1);
+					tree_element_active(C, scene, soops, te, OL_SETSEL_NORMAL);
 				}
 
 			}
 			else {
-				tree_element_type_active(C, scene, soops, te, tselem, 1 + (extend != 0), recursive);
+				tree_element_type_active(C, scene, soops, te, tselem,
+				                         extend ? OL_SETSEL_EXTEND : OL_SETSEL_NORMAL,
+				                         recursive);
 			}
 			
-			return 1;
+			return true;
 		}
 	}
 	
 	for (te = te->subtree.first; te; te = te->next) {
-		if (do_outliner_item_activate(C, scene, ar, soops, te, extend, recursive, mval)) return 1;
+		if (do_outliner_item_activate(C, scene, ar, soops, te, extend, recursive, mval)) {
+			return true;
+		}
 	}
-	return 0;
+	return false;
 }
 
 int outliner_item_do_activate(bContext *C, int x, int y, bool extend, bool recursive)
@@ -986,7 +1068,6 @@ static void outliner_item_border_select(Scene *scene, SpaceOops *soops, rctf *re
 			outliner_item_border_select(scene, soops, rectf, te, gesture_mode);
 		}
 	}
-	return;
 }
 
 static int outliner_border_select_exec(bContext *C, wmOperator *op)