diff --git a/source/blender/blenkernel/intern/screen.c b/source/blender/blenkernel/intern/screen.c
index f43bf3182c5..97bef99944a 100644
--- a/source/blender/blenkernel/intern/screen.c
+++ b/source/blender/blenkernel/intern/screen.c
@@ -67,11 +67,10 @@
 static void screen_free_data(ID *id)
 {
   bScreen *screen = (bScreen *)id;
-  ARegion *region;
 
   /* No animdata here. */
 
-  for (region = screen->regionbase.first; region; region = region->next) {
+  LISTBASE_FOREACH (ARegion *, region, &screen->regionbase) {
     BKE_area_region_free(NULL, region);
   }
 
@@ -325,14 +324,10 @@ static ListBase spacetypes = {NULL, NULL};
 /* not SpaceType itself */
 static void spacetype_free(SpaceType *st)
 {
-  ARegionType *art;
-  PanelType *pt;
-  HeaderType *ht;
-
-  for (art = st->regiontypes.first; art; art = art->next) {
+  LISTBASE_FOREACH (ARegionType *, art, &st->regiontypes) {
     BLI_freelistN(&art->drawcalls);
 
-    for (pt = art->paneltypes.first; pt; pt = pt->next) {
+    LISTBASE_FOREACH (PanelType *, pt, &art->paneltypes) {
       if (pt->rna_ext.free) {
         pt->rna_ext.free(pt->rna_ext.data);
       }
@@ -340,7 +335,7 @@ static void spacetype_free(SpaceType *st)
       BLI_freelistN(&pt->children);
     }
 
-    for (ht = art->headertypes.first; ht; ht = ht->next) {
+    LISTBASE_FOREACH (HeaderType *, ht, &art->headertypes) {
       if (ht->rna_ext.free) {
         ht->rna_ext.free(ht->rna_ext.data);
       }
@@ -355,9 +350,7 @@ static void spacetype_free(SpaceType *st)
 
 void BKE_spacetypes_free(void)
 {
-  SpaceType *st;
-
-  for (st = spacetypes.first; st; st = st->next) {
+  LISTBASE_FOREACH (SpaceType *, st, &spacetypes) {
     spacetype_free(st);
   }
 
@@ -366,9 +359,7 @@ void BKE_spacetypes_free(void)
 
 SpaceType *BKE_spacetype_from_id(int spaceid)
 {
-  SpaceType *st;
-
-  for (st = spacetypes.first; st; st = st->next) {
+  LISTBASE_FOREACH (SpaceType *, st, &spacetypes) {
     if (st->spaceid == spaceid) {
       return st;
     }
@@ -378,9 +369,7 @@ SpaceType *BKE_spacetype_from_id(int spaceid)
 
 ARegionType *BKE_regiontype_from_id_or_first(const SpaceType *st, int regionid)
 {
-  ARegionType *art;
-
-  for (art = st->regiontypes.first; art; art = art->next) {
+  LISTBASE_FOREACH (ARegionType *, art, &st->regiontypes) {
     if (art->regionid == regionid) {
       return art;
     }
@@ -393,9 +382,7 @@ ARegionType *BKE_regiontype_from_id_or_first(const SpaceType *st, int regionid)
 
 ARegionType *BKE_regiontype_from_id(const SpaceType *st, int regionid)
 {
-  ARegionType *art;
-
-  for (art = st->regiontypes.first; art; art = art->next) {
+  LISTBASE_FOREACH (ARegionType *, art, &st->regiontypes) {
     if (art->regionid == regionid) {
       return art;
     }
@@ -410,10 +397,8 @@ const ListBase *BKE_spacetypes_list(void)
 
 void BKE_spacetype_register(SpaceType *st)
 {
-  SpaceType *stype;
-
   /* sanity check */
-  stype = BKE_spacetype_from_id(st->spaceid);
+  SpaceType *stype = BKE_spacetype_from_id(st->spaceid);
   if (stype) {
     printf("error: redefinition of spacetype %s\n", stype->name);
     spacetype_free(stype);
@@ -432,14 +417,11 @@ bool BKE_spacetype_exists(int spaceid)
 
 void BKE_spacedata_freelist(ListBase *lb)
 {
-  SpaceLink *sl;
-  ARegion *region;
-
-  for (sl = lb->first; sl; sl = sl->next) {
+  LISTBASE_FOREACH (SpaceLink *, sl, lb) {
     SpaceType *st = BKE_spacetype_from_id(sl->spacetype);
 
     /* free regions for pushed spaces */
-    for (region = sl->regionbase.first; region; region = region->next) {
+    LISTBASE_FOREACH (ARegion *, region, &sl->regionbase) {
       BKE_area_region_free(st, region);
     }
 
@@ -510,12 +492,10 @@ ARegion *BKE_area_region_copy(const SpaceType *st, const ARegion *region)
 /* from lb2 to lb1, lb1 is supposed to be freed */
 static void region_copylist(SpaceType *st, ListBase *lb1, ListBase *lb2)
 {
-  ARegion *region;
-
   /* to be sure */
   BLI_listbase_clear(lb1);
 
-  for (region = lb2->first; region; region = region->next) {
+  LISTBASE_FOREACH (ARegion *, region, lb2) {
     ARegion *region_new = BKE_area_region_copy(st, region);
     BLI_addtail(lb1, region_new);
   }
@@ -524,11 +504,9 @@ static void region_copylist(SpaceType *st, ListBase *lb1, ListBase *lb2)
 /* lb1 should be empty */
 void BKE_spacedata_copylist(ListBase *lb1, ListBase *lb2)
 {
-  SpaceLink *sl;
-
   BLI_listbase_clear(lb1); /* to be sure */
 
-  for (sl = lb2->first; sl; sl = sl->next) {
+  LISTBASE_FOREACH (SpaceLink *, sl, lb2) {
     SpaceType *st = BKE_spacetype_from_id(sl->spacetype);
 
     if (st && st->duplicate) {
@@ -546,12 +524,8 @@ void BKE_spacedata_copylist(ListBase *lb1, ListBase *lb2)
 /* should be replaced in future by better local data handling for threads */
 void BKE_spacedata_draw_locks(int set)
 {
-  SpaceType *st;
-
-  for (st = spacetypes.first; st; st = st->next) {
-    ARegionType *art;
-
-    for (art = st->regiontypes.first; art; art = art->next) {
+  LISTBASE_FOREACH (SpaceType *, st, &spacetypes) {
+    LISTBASE_FOREACH (ARegionType *, art, &st->regiontypes) {
       if (set) {
         art->do_lock = art->lock;
       }
@@ -575,8 +549,10 @@ ARegion *BKE_spacedata_find_region_type(const SpaceLink *slink,
   ARegion *region = NULL;
 
   BLI_assert(BLI_findindex(&area->spacedata, slink) != -1);
-  for (region = regionbase->first; region; region = region->next) {
-    if (region->regiontype == region_type) {
+
+  LISTBASE_FOREACH (ARegion *, region_iter, regionbase) {
+    if (region_iter->regiontype == region_type) {
+      region = region_iter;
       break;
     }
   }
@@ -621,10 +597,8 @@ void BKE_screen_gizmo_tag_refresh(struct bScreen *screen)
     return;
   }
 
-  ScrArea *area;
-  ARegion *region;
-  for (area = screen->areabase.first; area; area = area->next) {
-    for (region = area->regionbase.first; region; region = region->next) {
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
+    LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
       if (region->gizmo_map != NULL) {
         region_refresh_tag_gizmomap_callback(region->gizmo_map);
       }
@@ -666,8 +640,6 @@ void BKE_area_region_panels_free(ListBase *panels)
 /* not region itself */
 void BKE_area_region_free(SpaceType *st, ARegion *region)
 {
-  uiList *uilst;
-
   if (st) {
     ARegionType *art = BKE_regiontype_from_id(st, region->regiontype);
 
@@ -685,7 +657,7 @@ void BKE_area_region_free(SpaceType *st, ARegion *region)
 
   BKE_area_region_panels_free(&region->panels);
 
-  for (uilst = region->ui_lists.first; uilst; uilst = uilst->next) {
+  LISTBASE_FOREACH (uiList *, uilst, &region->ui_lists) {
     if (uilst->dyn_data) {
       uiListDyn *dyn_data = uilst->dyn_data;
       if (dyn_data->items_filter_flags) {
@@ -715,9 +687,8 @@ void BKE_area_region_free(SpaceType *st, ARegion *region)
 void BKE_screen_area_free(ScrArea *area)
 {
   SpaceType *st = BKE_spacetype_from_id(area->spacetype);
-  ARegion *region;
 
-  for (region = area->regionbase.first; region; region = region->next) {
+  LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
     BKE_area_region_free(st, region);
   }
 
@@ -731,8 +702,7 @@ void BKE_screen_area_free(ScrArea *area)
 
 void BKE_screen_area_map_free(ScrAreaMap *area_map)
 {
-  for (ScrArea *area = area_map->areabase.first, *area_next; area; area = area_next) {
-    area_next = area->next;
+  LISTBASE_FOREACH_MUTABLE (ScrArea *, area, &area_map->areabase) {
     BKE_screen_area_free(area);
   }
 
@@ -751,10 +721,8 @@ void BKE_screen_free(bScreen *screen)
 
 ScrEdge *BKE_screen_find_edge(const bScreen *screen, ScrVert *v1, ScrVert *v2)
 {
-  ScrEdge *se;
-
   BKE_screen_sort_scrvert(&v1, &v2);
-  for (se = screen->edgebase.first; se; se = se->next) {
+  LISTBASE_FOREACH (ScrEdge *, se, &screen->edgebase) {
     if (se->v1 == v1 && se->v2 == v2) {
       return se;
     }
@@ -765,10 +733,8 @@ ScrEdge *BKE_screen_find_edge(const bScreen *screen, ScrVert *v1, ScrVert *v2)
 
 void BKE_screen_sort_scrvert(ScrVert **v1, ScrVert **v2)
 {
-  ScrVert *tmp;
-
   if (*v1 > *v2) {
-    tmp = *v1;
+    ScrVert *tmp = *v1;
     *v1 = *v2;
     *v2 = tmp;
   }
@@ -776,14 +742,9 @@ void BKE_screen_sort_scrvert(ScrVert **v1, ScrVert **v2)
 
 void BKE_screen_remove_double_scrverts(bScreen *screen)
 {
-  ScrVert *v1, *verg;
-  ScrEdge *se;
-  ScrArea *area;
-
-  verg = screen->vertbase.first;
-  while (verg) {
+  LISTBASE_FOREACH (ScrVert *, verg, &screen->vertbase) {
     if (verg->newv == NULL) { /* !!! */
-      v1 = verg->next;
+      ScrVert *v1 = verg->next;
       while (v1) {
         if (v1->newv == NULL) { /* !?! */
           if (v1->vec.x == verg->vec.x && v1->vec.y == verg->vec.y) {
@@ -794,12 +755,10 @@ void BKE_screen_remove_double_scrverts(bScreen *screen)
         v1 = v1->next;
       }
     }
-    verg = verg->next;
   }
 
   /* replace pointers in edges and faces */
-  se = screen->edgebase.first;
-  while (se) {
+  LISTBASE_FOREACH (ScrEdge *, se, &screen->edgebase) {
     if (se->v1->newv) {
       se->v1 = se->v1->newv;
     }
@@ -808,10 +767,8 @@ void BKE_screen_remove_double_scrverts(bScreen *screen)
     }
     /* edges changed: so.... */
     BKE_screen_sort_scrvert(&(se->v1), &(se->v2));
-    se = se->next;
   }
-  area = screen->areabase.first;
-  while (area) {
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
     if (area->v1->newv) {
       area->v1 = area->v1->newv;
     }
@@ -824,51 +781,39 @@ void BKE_screen_remove_double_scrverts(bScreen *screen)
     if (area->v4->newv) {
       area->v4 = area->v4->newv;
     }
-    area = area->next;
   }
 
   /* remove */
-  verg = screen->vertbase.first;
-  while (verg) {
-    v1 = verg->next;
+  LISTBASE_FOREACH_MUTABLE (ScrVert *, verg, &screen->vertbase) {
     if (verg->newv) {
       BLI_remlink(&screen->vertbase, verg);
       MEM_freeN(verg);
     }
-    verg = v1;
   }
 }
 
 void BKE_screen_remove_double_scredges(bScreen *screen)
 {
-  ScrEdge *verg, *se, *sn;
-
   /* compare */
-  verg = screen->edgebase.first;
-  while (verg) {
-    se = verg->next;
+  LISTBASE_FOREACH (ScrEdge *, verg, &screen->edgebase) {
+    ScrEdge *se = verg->next;
     while (se) {
-      sn = se->next;
+      ScrEdge *sn = se->next;
       if (verg->v1 == se->v1 && verg->v2 == se->v2) {
         BLI_remlink(&screen->edgebase, se);
         MEM_freeN(se);
       }
       se = sn;
     }
-    verg = verg->next;
   }
 }
 
 void BKE_screen_remove_unused_scredges(bScreen *screen)
 {
-  ScrEdge *se, *sen;
-  ScrArea *area;
-  int a = 0;
-
   /* sets flags when edge is used in area */
-  area = screen->areabase.first;
-  while (area) {
-    se = BKE_screen_find_edge(screen, area->v1, area->v2);
+  int a = 0;
+  LISTBASE_FOREACH_INDEX (ScrArea *, area, &screen->areabase, a) {
+    ScrEdge *se = BKE_screen_find_edge(screen, area->v1, area->v2);
     if (se == NULL) {
       printf("error: area %d edge 1 doesn't exist\n", a);
     }
@@ -896,12 +841,8 @@ void BKE_screen_remove_unused_scredges(bScreen *screen)
     else {
       se->flag = 1;
     }
-    area = area->next;
-    a++;
   }
-  se = screen->edgebase.first;
-  while (se) {
-    sen = se->next;
+  LISTBASE_FOREACH_MUTABLE (ScrEdge *, se, &screen->edgebase) {
     if (se->flag == 0) {
       BLI_remlink(&screen->edgebase, se);
       MEM_freeN(se);
@@ -909,27 +850,18 @@ void BKE_screen_remove_unused_scredges(bScreen *screen)
     else {
       se->flag = 0;
     }
-    se = sen;
   }
 }
 
 void BKE_screen_remove_unused_scrverts(bScreen *screen)
 {
-  ScrVert *sv, *svn;
-  ScrEdge *se;
-
   /* we assume edges are ok */
-
-  se = screen->edgebase.first;
-  while (se) {
+  LISTBASE_FOREACH (ScrEdge *, se, &screen->edgebase) {
     se->v1->flag = 1;
     se->v2->flag = 1;
-    se = se->next;
   }
 
-  sv = screen->vertbase.first;
-  while (sv) {
-    svn = sv->next;
+  LISTBASE_FOREACH_MUTABLE (ScrVert *, sv, &screen->vertbase) {
     if (sv->flag == 0) {
       BLI_remlink(&screen->vertbase, sv);
       MEM_freeN(sv);
@@ -937,7 +869,6 @@ void BKE_screen_remove_unused_scrverts(bScreen *screen)
     else {
       sv->flag = 0;
     }
-    sv = svn;
   }
 }
 
@@ -964,33 +895,33 @@ ARegion *BKE_area_find_region_type(const ScrArea *area, int region_type)
 
 ARegion *BKE_area_find_region_active_win(ScrArea *area)
 {
-  if (area) {
-    ARegion *region = BLI_findlink(&area->regionbase, area->region_active_win);
-    if (region && (region->regiontype == RGN_TYPE_WINDOW)) {
-      return region;
-    }
-
-    /* fallback to any */
-    return BKE_area_find_region_type(area, RGN_TYPE_WINDOW);
+  if (area == NULL) {
+    return NULL;
   }
-  return NULL;
+
+  ARegion *region = BLI_findlink(&area->regionbase, area->region_active_win);
+  if (region && (region->regiontype == RGN_TYPE_WINDOW)) {
+    return region;
+  }
+
+  /* fallback to any */
+  return BKE_area_find_region_type(area, RGN_TYPE_WINDOW);
 }
 
 ARegion *BKE_area_find_region_xy(ScrArea *area, const int regiontype, int x, int y)
 {
-  ARegion *region_found = NULL;
-  if (area) {
-    ARegion *region;
-    for (region = area->regionbase.first; region; region = region->next) {
-      if (ELEM(regiontype, RGN_TYPE_ANY, region->regiontype)) {
-        if (BLI_rcti_isect_pt(&region->winrct, x, y)) {
-          region_found = region;
-          break;
-        }
+  if (area == NULL) {
+    return NULL;
+  }
+
+  LISTBASE_FOREACH (ARegion *, region, &area->regionbase) {
+    if (ELEM(regiontype, RGN_TYPE_ANY, region->regiontype)) {
+      if (BLI_rcti_isect_pt(&region->winrct, x, y)) {
+        return region;
       }
     }
   }
-  return region_found;
+  return NULL;
 }
 
 /**
@@ -998,16 +929,14 @@ ARegion *BKE_area_find_region_xy(ScrArea *area, const int regiontype, int x, int
  */
 ARegion *BKE_screen_find_region_xy(bScreen *screen, const int regiontype, int x, int y)
 {
-  ARegion *region_found = NULL;
   LISTBASE_FOREACH (ARegion *, region, &screen->regionbase) {
     if (ELEM(regiontype, RGN_TYPE_ANY, region->regiontype)) {
       if (BLI_rcti_isect_pt(&region->winrct, x, y)) {
-        region_found = region;
-        break;
+        return region;
       }
     }
   }
-  return region_found;
+  return NULL;
 }
 
 /**
@@ -1016,15 +945,13 @@ ARegion *BKE_screen_find_region_xy(bScreen *screen, const int regiontype, int x,
  */
 ScrArea *BKE_screen_find_area_from_space(struct bScreen *screen, SpaceLink *sl)
 {
-  ScrArea *area;
-
-  for (area = screen->areabase.first; area; area = area->next) {
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
     if (BLI_findindex(&area->spacedata, sl) != -1) {
-      break;
+      return area;
     }
   }
 
-  return area;
+  return NULL;
 }
 
 /**
@@ -1033,13 +960,13 @@ ScrArea *BKE_screen_find_area_from_space(struct bScreen *screen, SpaceLink *sl)
  */
 ScrArea *BKE_screen_find_big_area(bScreen *screen, const int spacetype, const short min)
 {
-  ScrArea *area, *big = NULL;
-  int size, maxsize = 0;
+  ScrArea *big = NULL;
+  int maxsize = 0;
 
-  for (area = screen->areabase.first; area; area = area->next) {
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
     if (ELEM(spacetype, SPACE_TYPE_ANY, area->spacetype)) {
       if (min <= area->winx && min <= area->winy) {
-        size = area->winx * area->winy;
+        int size = area->winx * area->winy;
         if (size > maxsize) {
           maxsize = size;
           big = area;
@@ -1077,9 +1004,7 @@ void BKE_screen_view3d_sync(View3D *v3d, struct Scene *scene)
     v3d->camera = scene->camera;
 
     if (v3d->camera == NULL) {
-      ARegion *region;
-
-      for (region = v3d->regionbase.first; region; region = region->next) {
+      LISTBASE_FOREACH (ARegion *, region, &v3d->regionbase) {
         if (region->regiontype == RGN_TYPE_WINDOW) {
           RegionView3D *rv3d = region->regiondata;
           if (rv3d->persp == RV3D_CAMOB) {
@@ -1094,10 +1019,8 @@ void BKE_screen_view3d_sync(View3D *v3d, struct Scene *scene)
 void BKE_screen_view3d_scene_sync(bScreen *screen, Scene *scene)
 {
   /* are there cameras in the views that are not in the scene? */
-  ScrArea *area;
-  for (area = screen->areabase.first; area; area = area->next) {
-    SpaceLink *sl;
-    for (sl = area->spacedata.first; sl; sl = sl->next) {
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
+    LISTBASE_FOREACH (SpaceLink *, sl, &area->spacedata) {
       if (sl->spacetype == SPACE_VIEW3D) {
         View3D *v3d = (View3D *)sl;
         BKE_screen_view3d_sync(v3d, scene);