From 7c95f594d3f72d2d113490ec783e072418b4f1ef Mon Sep 17 00:00:00 2001
From: Bryan DiLaura <dilauraba@gmail.com>
Date: Fri, 9 Oct 2020 16:12:14 -0600
Subject: [PATCH] Close #12413: Refactor VISIBILITY_CACHE to use strong enum
 (#13136)

---
 src/openrct2/interface/Viewport.cpp      |  4 ++--
 src/openrct2/interface/Window.cpp        | 18 +++++++++---------
 src/openrct2/interface/Window.h          | 12 +++++++-----
 src/openrct2/interface/Window_internal.h |  2 +-
 4 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/src/openrct2/interface/Viewport.cpp b/src/openrct2/interface/Viewport.cpp
index 8d59a26a41..15a431c001 100644
--- a/src/openrct2/interface/Viewport.cpp
+++ b/src/openrct2/interface/Viewport.cpp
@@ -1691,7 +1691,7 @@ InteractionInfo get_map_coordinates_from_pos_window(rct_window* window, const Sc
 void viewport_invalidate(rct_viewport* viewport, int32_t left, int32_t top, int32_t right, int32_t bottom)
 {
     // if unknown viewport visibility, use the containing window to discover the status
-    if (viewport->visibility == VC_UNKNOWN)
+    if (viewport->visibility == VisibilityCache::Unknown)
     {
         auto windowManager = GetContext()->GetUiContext()->GetWindowManager();
         auto owner = windowManager->GetOwner(viewport);
@@ -1705,7 +1705,7 @@ void viewport_invalidate(rct_viewport* viewport, int32_t left, int32_t top, int3
         }
     }
 
-    if (viewport->visibility == VC_COVERED)
+    if (viewport->visibility == VisibilityCache::Covered)
         return;
 
     int32_t viewportLeft = viewport->viewPos.x;
diff --git a/src/openrct2/interface/Window.cpp b/src/openrct2/interface/Window.cpp
index 00b15b052b..cef0ede1a4 100644
--- a/src/openrct2/interface/Window.cpp
+++ b/src/openrct2/interface/Window.cpp
@@ -1969,16 +1969,16 @@ bool window_is_visible(rct_window* w)
     if (w == nullptr)
         return false;
 
-    if (w->visibility == VC_VISIBLE)
+    if (w->visibility == VisibilityCache::Visible)
         return true;
-    if (w->visibility == VC_COVERED)
+    if (w->visibility == VisibilityCache::Covered)
         return false;
 
     // only consider viewports, consider the main window always visible
     if (w->viewport == nullptr || w->classification == WC_MAIN_WINDOW)
     {
         // default to previous behaviour
-        w->visibility = VC_VISIBLE;
+        w->visibility = VisibilityCache::Visible;
         return true;
     }
 
@@ -1993,15 +1993,15 @@ bool window_is_visible(rct_window* w)
             && w_other.windowPos.x + w_other.width >= w->windowPos.x + w->width
             && w_other.windowPos.y + w_other.height >= w->windowPos.y + w->height)
         {
-            w->visibility = VC_COVERED;
-            w->viewport->visibility = VC_COVERED;
+            w->visibility = VisibilityCache::Covered;
+            w->viewport->visibility = VisibilityCache::Covered;
             return false;
         }
     }
 
     // default to previous behaviour
-    w->visibility = VC_VISIBLE;
-    w->viewport->visibility = VC_VISIBLE;
+    w->visibility = VisibilityCache::Visible;
+    w->viewport->visibility = VisibilityCache::Visible;
     return true;
 }
 
@@ -2052,10 +2052,10 @@ void window_reset_visibilities()
 {
     // reset window visibility status to unknown
     window_visit_each([](rct_window* w) {
-        w->visibility = VC_UNKNOWN;
+        w->visibility = VisibilityCache::Unknown;
         if (w->viewport != nullptr)
         {
-            w->viewport->visibility = VC_UNKNOWN;
+            w->viewport->visibility = VisibilityCache::Unknown;
         }
     });
 }
diff --git a/src/openrct2/interface/Window.h b/src/openrct2/interface/Window.h
index ed9b9f2152..b4e3738bd1 100644
--- a/src/openrct2/interface/Window.h
+++ b/src/openrct2/interface/Window.h
@@ -29,6 +29,8 @@ struct TitleSequence;
 struct TextInputSession;
 struct scenario_index_entry;
 
+enum class VisibilityCache : uint8_t;
+
 #define SCROLLABLE_ROW_HEIGHT 12
 #define LIST_ROW_HEIGHT 12
 #define TABLE_CELL_HEIGHT 12
@@ -142,7 +144,7 @@ struct rct_viewport
     uint32_t flags;
     ZoomLevel zoom;
     uint8_t var_11;
-    uint8_t visibility; // VISIBILITY_CACHE
+    VisibilityCache visibility;
 };
 
 /**
@@ -632,11 +634,11 @@ enum
     MODAL_RESULT_OK
 };
 
-enum VISIBILITY_CACHE
+enum class VisibilityCache : uint8_t
 {
-    VC_UNKNOWN,
-    VC_VISIBLE,
-    VC_COVERED
+    Unknown,
+    Visible,
+    Covered
 };
 
 enum class GuestListFilterType : int32_t
diff --git a/src/openrct2/interface/Window_internal.h b/src/openrct2/interface/Window_internal.h
index 039d078ed1..36d4db565e 100644
--- a/src/openrct2/interface/Window_internal.h
+++ b/src/openrct2/interface/Window_internal.h
@@ -88,7 +88,7 @@ struct rct_window
     ScreenCoordsXY savedViewPos;
     rct_windowclass classification;
     colour_t colours[6];
-    uint8_t visibility;
+    VisibilityCache visibility;
     uint16_t viewport_smart_follow_sprite; // Handles setting viewport target sprite etc
 
     void SetLocation(const CoordsXYZ& coords);