8 files changed, 92 insertions, 36 deletions
diff --git a/Source/Core/VideoBackends/Software/SWRenderer.cpp b/Source/Core/VideoBackends/Software/SWRenderer.cpp
index 4d9b821f5a..c128e6bd1a 100644
--- a/Source/Core/VideoBackends/Software/SWRenderer.cpp
+++ b/Source/Core/VideoBackends/Software/SWRenderer.cpp
@@ -128,12 +128,12 @@ u32 SWRenderer::AccessEFB(EFBAccessType type, u32 x, u32 y, u32 InputData)
 
 u16 SWRenderer::BBoxRead(int index)
 {
-  return BoundingBox::coords[index];
+  return BoundingBox::GetCoordinate(static_cast<BoundingBox::Coordinate>(index));
 }
 
 void SWRenderer::BBoxWrite(int index, u16 value)
 {
-  BoundingBox::coords[index] = value;
+  BoundingBox::SetCoordinate(static_cast<BoundingBox::Coordinate>(index), value);
 }
 
 void SWRenderer::ClearScreen(const MathUtil::Rectangle<int>& rc, bool colorEnable, bool alphaEnable,
diff --git a/Source/Core/VideoBackends/Software/Tev.cpp b/Source/Core/VideoBackends/Software/Tev.cpp
index 580ab58685..8d03cacac2 100644
--- a/Source/Core/VideoBackends/Software/Tev.cpp
+++ b/Source/Core/VideoBackends/Software/Tev.cpp
@@ -841,15 +841,8 @@ void Tev::Draw()
     EfbInterface::IncPerfCounterQuadCount(PQ_ZCOMP_OUTPUT);
   }
 
-  // branchless bounding box update
-  BoundingBox::coords[BoundingBox::LEFT] =
-      std::min((u16)Position[0], BoundingBox::coords[BoundingBox::LEFT]);
-  BoundingBox::coords[BoundingBox::RIGHT] =
-      std::max((u16)Position[0], BoundingBox::coords[BoundingBox::RIGHT]);
-  BoundingBox::coords[BoundingBox::TOP] =
-      std::min((u16)Position[1], BoundingBox::coords[BoundingBox::TOP]);
-  BoundingBox::coords[BoundingBox::BOTTOM] =
-      std::max((u16)Position[1], BoundingBox::coords[BoundingBox::BOTTOM]);
+  BoundingBox::Update(static_cast<u16>(Position[0]), static_cast<u16>(Position[0]),
+                      static_cast<u16>(Position[1]), static_cast<u16>(Position[1]));
 
 #if ALLOW_TEV_DUMPS
   if (g_ActiveConfig.bDumpTevStages)
diff --git a/Source/Core/VideoCommon/BPStructs.cpp b/Source/Core/VideoCommon/BPStructs.cpp
index f9be647114..6cff479396 100644
--- a/Source/Core/VideoCommon/BPStructs.cpp
+++ b/Source/Core/VideoCommon/BPStructs.cpp
@@ -279,7 +279,7 @@ static void BPWritten(const BPCmd& bp)
       // here. Not sure if there's a better spot to put this.
       // the number of lines copied is determined by the y scale * source efb height
 
-      BoundingBox::active = false;
+      BoundingBox::Disable();
       PixelShaderManager::SetBoundingBoxActive(false);
 
       float yScale;
@@ -448,8 +448,8 @@ static void BPWritten(const BPCmd& bp)
   case BPMEM_CLEARBBOX1:
   case BPMEM_CLEARBBOX2:
   {
-    u8 offset = bp.address & 2;
-    BoundingBox::active = true;
+    const u8 offset = bp.address & 2;
+    BoundingBox::Enable();
     PixelShaderManager::SetBoundingBoxActive(true);
 
     if (g_ActiveConfig.backend_info.bSupportsBBox && g_ActiveConfig.bBBoxEnable)
diff --git a/Source/Core/VideoCommon/BoundingBox.cpp b/Source/Core/VideoCommon/BoundingBox.cpp
index 4c9b6c4c3b..7c2127d353 100644
--- a/Source/Core/VideoCommon/BoundingBox.cpp
+++ b/Source/Core/VideoCommon/BoundingBox.cpp
@@ -3,20 +3,71 @@
 // Refer to the license.txt file included.
 
 #include "VideoCommon/BoundingBox.h"
+
+#include <algorithm>
+#include <array>
+
 #include "Common/ChunkFile.h"
 #include "Common/CommonTypes.h"
 
 namespace BoundingBox
 {
-// External vars
-bool active = false;
-u16 coords[4] = {0x80, 0xA0, 0x80, 0xA0};
+namespace
+{
+// Whether or not bounding box is enabled.
+bool s_is_active = false;
+
+// Current bounding box coordinates.
+std::array<u16, 4> s_coordinates{
+    0x80,
+    0xA0,
+    0x80,
+    0xA0,
+};
+}  // Anonymous namespace
+
+void Enable()
+{
+  s_is_active = true;
+}
+
+void Disable()
+{
+  s_is_active = false;
+}
+
+bool IsEnabled()
+{
+  return s_is_active;
+}
+
+u16 GetCoordinate(Coordinate coordinate)
+{
+  return s_coordinates[static_cast<u32>(coordinate)];
+}
+
+void SetCoordinate(Coordinate coordinate, u16 value)
+{
+  s_coordinates[static_cast<u32>(coordinate)] = value;
+}
+
+void Update(u16 left, u16 right, u16 top, u16 bottom)
+{
+  const u16 new_left = std::min(left, GetCoordinate(Coordinate::Left));
+  const u16 new_right = std::max(right, GetCoordinate(Coordinate::Right));
+  const u16 new_top = std::min(top, GetCoordinate(Coordinate::Top));
+  const u16 new_bottom = std::max(bottom, GetCoordinate(Coordinate::Bottom));
+
+  SetCoordinate(Coordinate::Left, new_left);
+  SetCoordinate(Coordinate::Right, new_right);
+  SetCoordinate(Coordinate::Top, new_top);
+  SetCoordinate(Coordinate::Bottom, new_bottom);
+}
 
-// Save state
 void DoState(PointerWrap& p)
 {
-  p.Do(active);
-  p.Do(coords);
+  p.Do(s_is_active);
+  p.DoArray(s_coordinates);
 }
 
 }  // namespace BoundingBox
diff --git a/Source/Core/VideoCommon/BoundingBox.h b/Source/Core/VideoCommon/BoundingBox.h
index e10b97cc06..f4000c488f 100644
--- a/Source/Core/VideoCommon/BoundingBox.h
+++ b/Source/Core/VideoCommon/BoundingBox.h
@@ -11,21 +11,33 @@ class PointerWrap;
 // Bounding Box manager
 namespace BoundingBox
 {
-// Determines if bounding box is active
-extern bool active;
-
-// Bounding box current coordinates
-extern u16 coords[4];
-
-enum
+// Indicates a coordinate of the bounding box.
+enum class Coordinate
 {
-  LEFT = 0,
-  RIGHT = 1,
-  TOP = 2,
-  BOTTOM = 3
+  Left,    // The X coordinate of the left side of the bounding box.
+  Right,   // The X coordinate of the right side of the bounding box.
+  Top,     // The Y coordinate of the top of the bounding box.
+  Bottom,  // The Y coordinate of the bottom of the bounding box.
 };
 
+// Enables bounding box.
+void Enable();
+
+// Disables bounding box.
+void Disable();
+
+// Determines if bounding box is enabled.
+bool IsEnabled();
+
+// Gets a particular coordinate for the bounding box.
+u16 GetCoordinate(Coordinate coordinate);
+
+// Sets a particular coordinate for the bounding box.
+void SetCoordinate(Coordinate coordinate, u16 value);
+
+// Updates all bounding box coordinates.
+void Update(u16 left, u16 right, u16 top, u16 bottom);
+
 // Save state
 void DoState(PointerWrap& p);
-
-};  // end of namespace BoundingBox
+}  // namespace BoundingBox
diff --git a/Source/Core/VideoCommon/PixelEngine.cpp b/Source/Core/VideoCommon/PixelEngine.cpp
index e5136e6d50..fc44841622 100644
--- a/Source/Core/VideoCommon/PixelEngine.cpp
+++ b/Source/Core/VideoCommon/PixelEngine.cpp
@@ -233,7 +233,7 @@ void RegisterMMIO(MMIO::Mapping* mmio, u32 base)
   for (int i = 0; i < 4; ++i)
   {
     mmio->Register(base | (PE_BBOX_LEFT + 2 * i), MMIO::ComplexRead<u16>([i](u32) {
-                     BoundingBox::active = false;
+                     BoundingBox::Disable();
                      PixelShaderManager::SetBoundingBoxActive(false);
                      return g_video_backend->Video_GetBoundingBox(i);
                    }),
diff --git a/Source/Core/VideoCommon/PixelShaderGen.cpp b/Source/Core/VideoCommon/PixelShaderGen.cpp
index 89d0bd933d..ee750988f8 100644
--- a/Source/Core/VideoCommon/PixelShaderGen.cpp
+++ b/Source/Core/VideoCommon/PixelShaderGen.cpp
@@ -179,7 +179,7 @@ PixelShaderUid GetPixelShaderUid()
   uid_data->genMode_numindstages = bpmem.genMode.numindstages;
   uid_data->genMode_numtevstages = bpmem.genMode.numtevstages;
   uid_data->genMode_numtexgens = bpmem.genMode.numtexgens;
-  uid_data->bounding_box = g_ActiveConfig.bBBoxEnable && BoundingBox::active;
+  uid_data->bounding_box = g_ActiveConfig.bBBoxEnable && BoundingBox::IsEnabled();
   uid_data->rgba6_format =
       bpmem.zcontrol.pixel_format == PEControl::RGBA6_Z24 && !g_ActiveConfig.bForceTrueColor;
   uid_data->dither = bpmem.blendmode.dither && uid_data->rgba6_format;
diff --git a/Source/Core/VideoCommon/VertexManagerBase.cpp b/Source/Core/VideoCommon/VertexManagerBase.cpp
index f1150dc340..ddbdd7e0f3 100644
--- a/Source/Core/VideoCommon/VertexManagerBase.cpp
+++ b/Source/Core/VideoCommon/VertexManagerBase.cpp
@@ -247,7 +247,7 @@ void VertexManagerBase::CommitBuffer(u32 num_vertices, u32 vertex_stride, u32 nu
 void VertexManagerBase::DrawCurrentBatch(u32 base_index, u32 num_indices, u32 base_vertex)
 {
   // If bounding box is enabled, we need to flush any changes first, then invalidate what we have.
-  if (::BoundingBox::active && g_ActiveConfig.bBBoxEnable &&
+  if (BoundingBox::IsEnabled() && g_ActiveConfig.bBBoxEnable &&
       g_ActiveConfig.backend_info.bSupportsBBox)
   {
     g_renderer->BBoxFlush();