From e83a69560a5ce71689045d7f561296ef6d1cd08f Mon Sep 17 00:00:00 2001
From: hogliux <fabian.renn@gmail.com>
Date: Wed, 22 Apr 2015 17:38:32 +0100
Subject: [PATCH] Fix for duplicateIfShared when image depends on other image
 via SubsectionImageData

---
 modules/juce_graphics/images/juce_Image.cpp | 13 +++++++++++--
 modules/juce_graphics/images/juce_Image.h   |  5 +++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/modules/juce_graphics/images/juce_Image.cpp b/modules/juce_graphics/images/juce_Image.cpp
index e7be9a3f47..17d20e5122 100644
--- a/modules/juce_graphics/images/juce_Image.cpp
+++ b/modules/juce_graphics/images/juce_Image.cpp
@@ -39,6 +39,11 @@ void ImagePixelData::sendDataChangeMessage()
     listeners.call (&Listener::imageDataChanged, this);
 }
 
+int ImagePixelData::getSharedCount() const noexcept 
+{ 
+    return getReferenceCount();
+}
+
 //==============================================================================
 ImageType::ImageType() {}
 ImageType::~ImageType() {}
@@ -179,7 +184,11 @@ public:
 
     ImageType* createType() const override    { return image->createType(); }
 
+    /* as we always hold a reference to image, don't double count */
+    int getSharedCount() const noexcept { return getReferenceCount() + image->getSharedCount() - 1; }
+
 private:
+    friend class Image;
     const ImagePixelData::Ptr image;
     const Rectangle<int> area;
 
@@ -246,7 +255,7 @@ Image::~Image()
 
 const Image Image::null;
 
-int Image::getReferenceCount() const noexcept           { return image == nullptr ? 0 : image->getReferenceCount(); }
+int Image::getReferenceCount() const noexcept           { return image == nullptr ? 0 : image->getSharedCount(); }
 int Image::getWidth() const noexcept                    { return image == nullptr ? 0 : image->width; }
 int Image::getHeight() const noexcept                   { return image == nullptr ? 0 : image->height; }
 Rectangle<int> Image::getBounds() const noexcept        { return image == nullptr ? Rectangle<int>() : Rectangle<int> (image->width, image->height); }
@@ -263,7 +272,7 @@ LowLevelGraphicsContext* Image::createLowLevelContext() const
 
 void Image::duplicateIfShared()
 {
-    if (image != nullptr && image->getReferenceCount() > 1)
+    if (getReferenceCount() > 1)
         image = image->clone();
 }
 
diff --git a/modules/juce_graphics/images/juce_Image.h b/modules/juce_graphics/images/juce_Image.h
index 0f67b4eefe..0e624ebcc8 100644
--- a/modules/juce_graphics/images/juce_Image.h
+++ b/modules/juce_graphics/images/juce_Image.h
@@ -443,6 +443,11 @@ public:
     virtual ImageType* createType() const = 0;
     /** Initialises a BitmapData object. */
     virtual void initialiseBitmapData (Image::BitmapData&, int x, int y, Image::BitmapData::ReadWriteMode) = 0;
+    /** Returns the number of Image objects which are currently referring to the same internal
+        shared image data. This is different to the reference count as an instance of ImagePixelData
+        can internally depend on another ImagePixelData via it's member variables. */
+    virtual int getSharedCount() const noexcept;
+
 
     /** The pixel format of the image data. */
     const Image::PixelFormat pixelFormat;