From b66f78bacff656fbb0dcf7f86d74567443de8081 Mon Sep 17 00:00:00 2001
From: Tom Poole <thomas.poole@roli.com>
Date: Wed, 3 Oct 2018 12:47:41 +0100
Subject: [PATCH] Fixed some CoreGraphics image issues in the latest iOS and
 MacOS SDKs

---
 modules/juce_graphics/images/juce_Image.cpp   |  4 +-
 .../native/juce_mac_CoreGraphicsContext.mm    | 79 ++++++++++++++++++-
 2 files changed, 77 insertions(+), 6 deletions(-)

diff --git a/modules/juce_graphics/images/juce_Image.cpp b/modules/juce_graphics/images/juce_Image.cpp
index 4bb9262e7a..0f3b1290b2 100644
--- a/modules/juce_graphics/images/juce_Image.cpp
+++ b/modules/juce_graphics/images/juce_Image.cpp
@@ -252,13 +252,13 @@ Image& Image::operator= (const Image& other)
 }
 
 Image::Image (Image&& other) noexcept
-    : image (static_cast<ImagePixelData::Ptr&&> (other.image))
+    : image (std::move (other.image))
 {
 }
 
 Image& Image::operator= (Image&& other) noexcept
 {
-    image = static_cast<ImagePixelData::Ptr&&> (other.image);
+    image = std::move (other.image);
     return *this;
 }
 
diff --git a/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm b/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
index d89822c4f4..9d41590fce 100644
--- a/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
+++ b/modules/juce_graphics/native/juce_mac_CoreGraphicsContext.mm
@@ -27,6 +27,61 @@
 namespace juce
 {
 
+#if (JUCE_IOS && defined (__IPHONE_12_0))
+ #define JUCE_CORE_GRAPHICS_NEEDS_DELAYED_GARBAGE_COLLECTION 1
+#endif
+
+#if JUCE_CORE_GRAPHICS_NEEDS_DELAYED_GARBAGE_COLLECTION
+class CoreGraphicsImageGarbageCollector   : public Timer,
+                                            public DeletedAtShutdown
+{
+public:
+    CoreGraphicsImageGarbageCollector()
+    {
+        // TODO: Add an assertion here telling JUCE developers to move to the
+        // latest SDK if/when the CoreGraphics memory handling is fixed.
+    }
+
+    ~CoreGraphicsImageGarbageCollector()
+    {
+        clearSingletonInstance();
+    }
+
+    JUCE_DECLARE_SINGLETON (CoreGraphicsImageGarbageCollector, false)
+
+    void addItem (HeapBlock<uint8>&& data)
+    {
+        ScopedLock lock (queueLock);
+
+        queue.emplace_back (Time::getApproximateMillisecondCounter(), std::move (data));
+
+        if (! isTimerRunning())
+            startTimer (timeDelta);
+    }
+
+    void timerCallback() override
+    {
+        ScopedLock lock (queueLock);
+
+        auto cutoffTime = Time::getApproximateMillisecondCounter() - timeDelta;
+
+        auto it = std::find_if (queue.begin(), queue.end(),
+                                [cutoffTime](const std::pair<int32, HeapBlock<uint8>>& x) { return x.first > cutoffTime; });
+        queue.erase (queue.begin(), it);
+
+        queue.empty() ? stopTimer() : startTimer (timeDelta);
+    }
+
+private:
+    CriticalSection queueLock;
+    std::vector<std::pair<int32, HeapBlock<uint8>>> queue;
+    static constexpr int timeDelta = 50;
+};
+
+JUCE_IMPLEMENT_SINGLETON (CoreGraphicsImageGarbageCollector)
+#endif
+
+//==============================================================================
 class CoreGraphicsImage   : public ImagePixelData
 {
 public:
@@ -36,7 +91,16 @@ public:
         pixelStride = format == Image::RGB ? 3 : ((format == Image::ARGB) ? 4 : 1);
         lineStride = (pixelStride * jmax (1, width) + 3) & ~3;
 
-        imageData.allocate ((size_t) lineStride * (size_t) jmax (1, height), clearImage);
+        auto numComponents = (size_t) lineStride * (size_t) jmax (1, height);
+
+       # if JUCE_MAC && defined (__MAC_10_14)
+        // This version of the SDK intermittently requires a bit of extra space
+        // at the end of the image data. This feels like something has gone
+        // wrong in Apple's code.
+        numComponents += (size_t) lineStride;
+       #endif
+
+        imageData.allocate (numComponents, clearImage);
 
         CGColorSpaceRef colourSpace = (format == Image::SingleChannel) ? CGColorSpaceCreateDeviceGray()
                                                                        : CGColorSpaceCreateDeviceRGB();
@@ -51,6 +115,10 @@ public:
     {
         freeCachedImageRef();
         CGContextRelease (context);
+
+       #if JUCE_CORE_GRAPHICS_NEEDS_DELAYED_GARBAGE_COLLECTION
+        CoreGraphicsImageGarbageCollector::getInstance()->addItem (std::move (imageData));
+       #endif
     }
 
     LowLevelGraphicsContext* createLowLevelContext() override
@@ -123,7 +191,8 @@ public:
 
         CGImageRef imageRef = CGImageCreate ((size_t) srcData.width,
                                              (size_t) srcData.height,
-                                             8, (size_t) srcData.pixelStride * 8,
+                                             8,
+                                             (size_t) srcData.pixelStride * 8,
                                              (size_t) srcData.lineStride,
                                              colourSpace, getCGImageFlags (juceImage.getFormat()), provider,
                                              0, true, kCGRenderingIntentDefault);
@@ -493,8 +562,10 @@ void CoreGraphicsContext::drawImage (const Image& sourceImage, const AffineTrans
 {
     auto iw = sourceImage.getWidth();
     auto ih = sourceImage.getHeight();
-    CGImageRef image = CoreGraphicsImage::getCachedImageRef (sourceImage, sourceImage.getFormat() == Image::PixelFormat::SingleChannel ? greyColourSpace
-                                                                                                                                       : rgbColourSpace);
+
+    auto colourSpace = sourceImage.getFormat() == Image::PixelFormat::SingleChannel ? greyColourSpace
+                                                                                    : rgbColourSpace;
+    CGImageRef image = CoreGraphicsImage::getCachedImageRef (sourceImage, colourSpace);
 
     CGContextSaveGState (context);
     CGContextSetAlpha (context, state->fillType.getOpacity());