From c94b8e1712e84802bd7b7cb9c8f00306daafc55f Mon Sep 17 00:00:00 2001
From: reuk <reuk@users.noreply.github.com>
Date: Mon, 12 Aug 2024 20:15:06 +0100
Subject: [PATCH] Direct2D: Refactor paintAreas handling in graphics contexts

---
 .../juce_Direct2DGraphicsContext_windows.cpp  | 20 +++++++------------
 .../juce_Direct2DHwndContext_windows.cpp      | 14 ++++++-------
 .../juce_Direct2DImageContext_windows.cpp     | 10 +++++-----
 3 files changed, 19 insertions(+), 25 deletions(-)

diff --git a/modules/juce_graphics/native/juce_Direct2DGraphicsContext_windows.cpp b/modules/juce_graphics/native/juce_Direct2DGraphicsContext_windows.cpp
index 3937626665..089df2a950 100644
--- a/modules/juce_graphics/native/juce_Direct2DGraphicsContext_windows.cpp
+++ b/modules/juce_graphics/native/juce_Direct2DGraphicsContext_windows.cpp
@@ -547,7 +547,6 @@ protected:
     Direct2DGraphicsContext& owner;
     SharedResourcePointer<DirectX> directX;
     SharedResourcePointer<Direct2DFactories> directWrite;
-    RectangleList<int> paintAreas;
 
     std::optional<Direct2DDeviceResources> deviceResources;
 
@@ -568,8 +567,6 @@ protected:
 
     virtual ComSmartPtr<ID2D1Image> getDeviceContextTarget() const = 0;
 
-    virtual void updatePaintAreas() = 0;
-
     virtual bool checkPaintReady()
     {
         return deviceResources.has_value();
@@ -602,8 +599,8 @@ public:
         prepare();
 
         // Anything to paint?
-        updatePaintAreas();
-        auto paintBounds = paintAreas.getBounds();
+        const auto paintAreas = getPaintAreas();
+        const auto paintBounds = paintAreas.getBounds();
 
         if (! getFrameSize().intersects (paintBounds) || paintBounds.isEmpty())
             return nullptr;
@@ -705,12 +702,8 @@ public:
         return deviceResources->deviceContext;
     }
 
-    const auto& getPaintAreas() const noexcept
-    {
-        return paintAreas;
-    }
-
-    virtual Rectangle<int> getFrameSize() = 0;
+    virtual RectangleList<int> getPaintAreas() const = 0;
+    virtual Rectangle<int> getFrameSize() const = 0;
 
     void setDeviceContextTransform (AffineTransform transform)
     {
@@ -893,7 +886,8 @@ Direct2DGraphicsContext::~Direct2DGraphicsContext() = default;
 
 bool Direct2DGraphicsContext::startFrame (float dpiScale)
 {
-    auto pimpl = getPimpl();
+    const auto pimpl = getPimpl();
+    const auto paintAreas = pimpl->getPaintAreas();
     currentState = pimpl->startFrame (dpiScale);
 
     if (currentState == nullptr)
@@ -903,7 +897,7 @@ bool Direct2DGraphicsContext::startFrame (float dpiScale)
     {
         resetPendingClipList();
 
-        clipToRectangleList (pimpl->getPaintAreas());
+        clipToRectangleList (paintAreas);
 
         // Clear the buffer *after* setting the clip region
         clearTargetBuffer();
diff --git a/modules/juce_graphics/native/juce_Direct2DHwndContext_windows.cpp b/modules/juce_graphics/native/juce_Direct2DHwndContext_windows.cpp
index 776f7a7d90..0bc5a604bc 100644
--- a/modules/juce_graphics/native/juce_Direct2DHwndContext_windows.cpp
+++ b/modules/juce_graphics/native/juce_Direct2DHwndContext_windows.cpp
@@ -371,18 +371,18 @@ private:
         Pimpl::teardown();
     }
 
-    void updatePaintAreas() override
+    RectangleList<int> getPaintAreas() const override
     {
         // Does the entire buffer need to be filled?
         if (swap.state == SwapChain::State::bufferAllocated || resizing)
-            deferredRepaints = swap.getSize();
+            return swap.getSize();
 
         // If the window alpha is less than 1.0, clip to the union of the
         // deferred repaints so the device context Clear() works correctly
         if (targetAlpha < 1.0f || ! opaque)
-            paintAreas = deferredRepaints.getBounds();
-        else
-            paintAreas = deferredRepaints;
+            return deferredRepaints.getBounds();
+
+        return deferredRepaints;
     }
 
     bool checkPaintReady() override
@@ -436,7 +436,7 @@ public:
         return Rectangle<int>::leftTopRightBottom (clientRect.left, clientRect.top, clientRect.right, clientRect.bottom);
     }
 
-    Rectangle<int> getFrameSize() override
+    Rectangle<int> getFrameSize() const override
     {
         return getClientRect();
     }
@@ -523,7 +523,7 @@ public:
         // next frame
         JUCE_TRACE_LOG_D2D_PAINT_CALL (etw::direct2dHwndPaintStart, owner.getFrameId());
 
-        presentation.getPresentation()->setPaintAreas (paintAreas);
+        presentation.getPresentation()->setPaintAreas (getPaintAreas());
 
         deferredRepaints.clear();
 
diff --git a/modules/juce_graphics/native/juce_Direct2DImageContext_windows.cpp b/modules/juce_graphics/native/juce_Direct2DImageContext_windows.cpp
index baa8a4fa05..e6d9ec3dca 100644
--- a/modules/juce_graphics/native/juce_Direct2DImageContext_windows.cpp
+++ b/modules/juce_graphics/native/juce_Direct2DImageContext_windows.cpp
@@ -46,15 +46,15 @@ public:
     {
     }
 
-    Rectangle<int> getFrameSize() override
+    Rectangle<int> getFrameSize() const override
     {
         const auto targetBitmap = getBitmap();
 
         if (targetBitmap == nullptr)
             return {};
 
-        auto size = targetBitmap->GetSize();
-        return Rectangle<float> { size.width, size.height }.getSmallestIntegerContainer();
+        const auto size = targetBitmap->GetSize();
+        return { (int) size.width, (int) size.height };
     }
 
     ComSmartPtr<ID2D1Image> getDeviceContextTarget() const override
@@ -81,9 +81,9 @@ private:
         return target->getAdapterD2D1Bitmap();
     }
 
-    void updatePaintAreas() override
+    RectangleList<int> getPaintAreas() const override
     {
-        paintAreas = getFrameSize();
+        return getFrameSize();
     }
 
     Direct2DPixelData::Ptr target;