Refactor: Solve invalid icon-id enum values, use type alias

Some code attempted to use `BIFIconID` instead of `int` to pass around
icon-ids. Problem is, that this is just a subset of the allowed ids,
more icons may be created at runtime and extend the range of valid
icon-ids. Such icons could give runtime warning prints.

Idea is to use a `using BIFIconID = int;` instead. This way there is
still a descriptive type name, while the whole dynamic range of possible
icon-ids is supported.

Additionally multiple `using BIFIconID = int;` declarations are valid,
so we can place these in multiple headers and use the type name in APIs
instead of just `int`, whithout having to include a single header
defining them. A type mismatch (one instance differs from the others)
will result in a compiler error.

Pull Request: https://projects.blender.org/blender/blender/pulls/111052

source/blender/editors/include/UI_resources.hh

@@ -9,6 +9,7 @@
 #pragma once
 
 #include "BLI_sys_types.h"
+#include "BLI_utildefines.h"
 
 struct bTheme;
 
@@ -18,12 +19,21 @@ struct bTheme;
 #define DEF_ICON_COLOR(name) ICON_##name,
 #define DEF_ICON_BLANK(name) ICON_BLANK_##name,
 
-enum BIFIconID {
+/**
+ * Builtin icons with a compile-time icon-id. Dynamically created icons such as preview image
+ * icons get a dynamic icon-id <= #BIFICONID_LAST_STATIC, #BIFIconID can hold both.
+ */
+enum BIFIconID_Static {
 /* ui */
 #include "UI_icons.hh"
-  BIFICONID_LAST,
+  BIFICONID_LAST_STATIC,
 };
 
+/** Type that fits all compile time and dynamic icon-ids. */
+using BIFIconID = int;
+BLI_STATIC_ASSERT(sizeof(BIFIconID_Static) <= sizeof(BIFIconID),
+                  "Expected all builtin icon IDs to fit into `BIFIconID`");
+
 #define BIFICONID_FIRST (ICON_NONE)
 
 /* use to denote intentionally unset theme color */

source/blender/editors/interface/interface.cc

@@ -1691,7 +1691,7 @@ static PointerRNA *ui_but_extra_operator_icon_add_ptr(uiBut *but,
 {
   uiButExtraOpIcon *extra_op_icon = MEM_new<uiButExtraOpIcon>(__func__);
 
-  extra_op_icon->icon = (BIFIconID)icon;
+  extra_op_icon->icon = icon;
   extra_op_icon->optype_params = MEM_cnew<wmOperatorCallParams>(__func__);
   extra_op_icon->optype_params->optype = optype;
   extra_op_icon->optype_params->opptr = MEM_cnew<PointerRNA>(__func__);
@@ -1847,7 +1847,7 @@ static void ui_but_predefined_extra_operator_icons_add(uiBut *but)
         return;
       }
     }
-    ui_but_extra_operator_icon_add_ptr(but, optype, WM_OP_INVOKE_DEFAULT, int(icon));
+    ui_but_extra_operator_icon_add_ptr(but, optype, WM_OP_INVOKE_DEFAULT, icon);
   }
 }
 
@@ -3857,7 +3857,7 @@ static void ui_but_update_ex(uiBut *but, const bool validate)
               const size_t slen = strlen(item.name);
               ui_but_string_free_internal(but);
               ui_but_string_set_internal(but, item.name, slen);
-              but->icon = (BIFIconID)item.icon;
+              but->icon = item.icon;
             }
           }
         }
@@ -4270,7 +4270,7 @@ void ui_def_but_icon(uiBut *but, const int icon, const int flag)
                             icon,
                             (flag & UI_BUT_ICON_PREVIEW) != 0);
   }
-  but->icon = (BIFIconID)icon;
+  but->icon = icon;
   but->flag |= flag;
 
   if (but->str && but->str[0]) {

source/blender/editors/interface/interface_context_path.cc

@@ -39,16 +39,15 @@ void context_path_add_generic(Vector<ContextPathItem> &path,
   RNA_struct_name_get_alloc(&rna_ptr, name, sizeof(name), nullptr);
 
   /* Use a blank icon by default to check whether to retrieve it automatically from the type. */
-  const BIFIconID icon = icon_override == ICON_NONE ?
-                             static_cast<BIFIconID>(RNA_struct_ui_icon(rna_ptr.type)) :
-                             icon_override;
+  const BIFIconID icon = icon_override == ICON_NONE ? RNA_struct_ui_icon(rna_ptr.type) :
+                                                      icon_override;
 
   if (&rna_type == &RNA_NodeTree) {
     ID *id = (ID *)ptr;
-    path.append({name, int(icon), ID_REAL_USERS(id)});
+    path.append({name, icon, ID_REAL_USERS(id)});
   }
   else {
-    path.append({name, int(icon), 1});
+    path.append({name, icon, 1});
   }
 }
 

source/blender/editors/interface/interface_template_search_menu.cc

@@ -299,7 +299,7 @@ static bool menu_items_to_ui_button(MenuSearch_Item *item, uiBut *but)
       *drawstr_sep = '\0';
     }
 
-    but->icon = (BIFIconID)item->icon;
+    but->icon = item->icon;
     but->str = but->strdata;
   }
 

source/blender/editors/interface/interface_widgets.cc

@@ -2313,7 +2313,7 @@ static void widget_draw_text_icon(const uiFontStyle *fstyle,
 
   /* Big previews with optional text label below */
   if (but->flag & UI_BUT_ICON_PREVIEW && ui_block_is_menu(but->block)) {
-    const BIFIconID icon = BIFIconID(ui_but_icon(but));
+    const BIFIconID icon = ui_but_icon(but);
     int icon_size = BLI_rcti_size_y(rect);
     int text_size = 0;
 
@@ -2350,7 +2350,7 @@ static void widget_draw_text_icon(const uiFontStyle *fstyle,
     }
 #endif
 
-    const BIFIconID icon = BIFIconID(ui_but_icon(but));
+    const BIFIconID icon = ui_but_icon(but);
     const int icon_size_init = is_tool ? ICON_DEFAULT_HEIGHT_TOOLBAR : ICON_DEFAULT_HEIGHT;
     const float icon_size = icon_size_init / (but->block->aspect * UI_INV_SCALE_FAC);
     const float icon_padding = 2 * UI_SCALE_FAC;
@@ -5632,10 +5632,10 @@ void ui_draw_preview_item_stateless(const uiFontStyle *fstyle,
   }
   GPU_blend(GPU_BLEND_ALPHA);
   if (draw_as_icon) {
-    widget_draw_icon_centered(BIFIconID(iconid), 1.0f, alpha, rect, text_col);
+    widget_draw_icon_centered(iconid, 1.0f, alpha, rect, text_col);
   }
   else {
-    widget_draw_preview(BIFIconID(iconid), alpha, rect);
+    widget_draw_preview(iconid, alpha, rect);
   }
   GPU_blend(GPU_BLEND_NONE);
 

source/blender/editors/space_outliner/outliner_draw.cc

@@ -2446,7 +2446,7 @@ static BIFIconID tree_element_get_icon_from_id(const ID *id)
         return ICON_FILE_TEXT;
       }
       /* Helps distinguish text-based formats like the file-browser does. */
-      return (BIFIconID)ED_file_extension_icon(text->filepath);
+      return ED_file_extension_icon(text->filepath);
     }
     case ID_GR:
       return ICON_OUTLINER_COLLECTION;
@@ -2493,7 +2493,7 @@ static BIFIconID tree_element_get_icon_from_id(const ID *id)
     case ID_NT: {
       const bNodeTree *ntree = (bNodeTree *)id;
       const bNodeTreeType *ntreetype = ntree->typeinfo;
-      return (BIFIconID)ntreetype->ui_icon;
+      return ntreetype->ui_icon;
     }
     case ID_MC:
       return ICON_SEQUENCE;
@@ -3366,7 +3366,7 @@ static void outliner_draw_tree_element(bContext *C,
     if (ELEM(tselem->type, TSE_SOME_ID, TSE_LAYER_COLLECTION) ||
         (te_rna_struct && RNA_struct_is_ID(te_rna_struct->getPointerRNA().type)))
     {
-      const BIFIconID lib_icon = (BIFIconID)UI_icon_from_library(tselem->id);
+      const BIFIconID lib_icon = UI_icon_from_library(tselem->id);
       if (lib_icon != ICON_NONE) {
         UI_icon_draw_alpha(
             float(startx) + offsx + 2 * ufac, float(*starty) + 2 * ufac, lib_icon, alpha_fac);

source/blender/editors/space_outliner/tree/tree_element_overrides.cc

@@ -256,7 +256,7 @@ StringRefNull TreeElementOverridesPropertyOperation::getOverrideOperationLabel()
 std::optional<BIFIconID> TreeElementOverridesPropertyOperation::getIcon() const
 {
   if (const std::optional<PointerRNA> col_item_ptr = get_collection_ptr()) {
-    return (BIFIconID)RNA_struct_ui_icon(col_item_ptr->type);
+    return RNA_struct_ui_icon(col_item_ptr->type);
   }
 
   return {};
@@ -451,7 +451,7 @@ void OverrideRNAPathTreeBuilder::ensure_entire_collection(
 
 static BIFIconID get_property_icon(PointerRNA &ptr, PropertyRNA &prop)
 {
-  BIFIconID icon = (BIFIconID)RNA_property_ui_icon(&prop);
+  BIFIconID icon = RNA_property_ui_icon(&prop);
   if (icon) {
     return icon;
   }
@@ -460,7 +460,7 @@ static BIFIconID get_property_icon(PointerRNA &ptr, PropertyRNA &prop)
    * #Object.modifiers property). */
   if (RNA_property_type(&prop) == PROP_COLLECTION) {
     const StructRNA *coll_ptr_type = RNA_property_pointer_type(&ptr, &prop);
-    icon = (BIFIconID)RNA_struct_ui_icon(coll_ptr_type);
+    icon = RNA_struct_ui_icon(coll_ptr_type);
     if (icon != ICON_DOT) {
       return icon;
     }
@@ -503,7 +503,7 @@ TreeElement &OverrideRNAPathTreeBuilder::ensure_label_element_for_ptr(TreeElemen
         TSE_GENERIC_LABEL,
         index++);
     TreeElementLabel *te_label = tree_element_cast<TreeElementLabel>(new_te);
-    te_label->setIcon((BIFIconID)RNA_struct_ui_icon(ptr.type));
+    te_label->setIcon(RNA_struct_ui_icon(ptr.type));
 
     MEM_delete(dyn_name);
 

source/blender/makesrna/intern/rna_brush.cc

@@ -759,7 +759,7 @@ static void rna_Brush_reset_icon(Brush *br)
     return;
   }
 
-  if (id->icon_id >= BIFICONID_LAST) {
+  if (id->icon_id >= BIFICONID_LAST_STATIC) {
     BKE_icon_id_delete(id);
     BKE_previewimg_id_free(id);
   }

source/blender/windowmanager/intern/wm_init_exit.cc

@@ -257,7 +257,7 @@ void WM_init(bContext *C, int argc, const char **argv)
   /* Init icons before reading .blend files for preview icons, which can
    * get triggered by the depsgraph. This is also done in background mode
    * for scripts that do background processing with preview icons. */
-  BKE_icons_init(BIFICONID_LAST);
+  BKE_icons_init(BIFICONID_LAST_STATIC);
 
   /* Reports can't be initialized before the window-manager,
    * but keep before file reading, since that may report errors */