Recognize RGBA8888 formats when converting to CGImage

qt_mac_image_to_cgimage incorrectly assumes any 32bit QImage format is
one ARGB32 form. This is no longer correct with the introduction of
RGBA8888 format.

This patch recognizes the formats a maps them to the native support for
them in CGImage. It also removes a duplicate method.

The codepath appears to be only used by the old coregraphics paintengine
and MIME handling. Which means RGBA images are probably printed and
copy/pasted incorrectly at the moment.

Task-number: QTBUG-36818
Change-Id: Ie6292defdbaef3e6105cf993e12911eded0918dc
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>

2 files changed, 17 insertions, 45 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoahelpers.mm b/src/plugins/platforms/cocoa/qcocoahelpers.mm
index 8975605e5c..a73944c07c 100644
--- a/src/plugins/platforms/cocoa/qcocoahelpers.mm
+++ b/src/plugins/platforms/cocoa/qcocoahelpers.mm
@@ -102,21 +102,31 @@ CGImageRef qt_mac_toCGImage(const QImage &inImage)
     uint cgflags = kCGImageAlphaNone;
     switch (image.format()) {
     case QImage::Format_ARGB32_Premultiplied:
-        cgflags = kCGImageAlphaPremultipliedFirst;
+        cgflags = kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host;
         break;
     case QImage::Format_ARGB32:
-        cgflags = kCGImageAlphaFirst;
+        cgflags = kCGImageAlphaFirst | kCGBitmapByteOrder32Host;
         break;
     case QImage::Format_RGB32:
-        cgflags = kCGImageAlphaNoneSkipFirst;
+        cgflags = kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Host;
         break;
     case QImage::Format_RGB888:
-        cgflags |= kCGImageAlphaNone;
-    break;
+        cgflags = kCGImageAlphaNone | kCGBitmapByteOrder32Big;
+        break;
+    case QImage::Format_RGBA8888_Premultiplied:
+        cgflags = kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big;
+        break;
+    case QImage::Format_RGBA8888:
+        cgflags = kCGImageAlphaLast | kCGBitmapByteOrder32Big;
+        break;
+    case QImage::Format_RGBX8888:
+        cgflags = kCGImageAlphaNoneSkipLast | kCGBitmapByteOrder32Big;
+        break;
     default:
+        Q_ASSERT(false); // Should never be reached.
         break;
     }
-    cgflags |= kCGBitmapByteOrder32Host;
+
     QCFType<CGDataProviderRef> dataProvider = qt_mac_CGDataProvider(image);
     return CGImageCreate(image.width(), image.height(), 8, 32,
                          image.bytesPerLine(),
diff --git a/src/plugins/platforms/cocoa/qpaintengine_mac.mm b/src/plugins/platforms/cocoa/qpaintengine_mac.mm
index 61fbe3a61f..ef67d1166f 100644
--- a/src/plugins/platforms/cocoa/qpaintengine_mac.mm
+++ b/src/plugins/platforms/cocoa/qpaintengine_mac.mm
@@ -979,43 +979,6 @@ static void drawImageReleaseData (void *info, const void *, size_t)
     delete static_cast<QImage *>(info);
 }
 
-CGImageRef qt_mac_createCGImageFromQImage(const QImage &img, const QImage **imagePtr = 0)
-{
-    QImage *image;
-    if (img.depth() != 32)
-        image = new QImage(img.convertToFormat(QImage::Format_ARGB32_Premultiplied));
-    else
-        image = new QImage(img);
-
-    uint cgflags = kCGImageAlphaNone;
-    switch (image->format()) {
-    case QImage::Format_ARGB32_Premultiplied:
-        cgflags = kCGImageAlphaPremultipliedFirst;
-        break;
-    case QImage::Format_ARGB32:
-        cgflags = kCGImageAlphaFirst;
-        break;
-    case QImage::Format_RGB32:
-        cgflags = kCGImageAlphaNoneSkipFirst;
-    default:
-        break;
-    }
-#if defined(kCGBitmapByteOrder32Host) //only needed because CGImage.h added symbols in the minor version
-    cgflags |= kCGBitmapByteOrder32Host;
-#endif
-    QCFType<CGDataProviderRef> dataProvider = CGDataProviderCreateWithData(image,
-                                                          static_cast<const QImage *>(image)->bits(),
-                                                          image->byteCount(),
-                                                          drawImageReleaseData);
-    if (imagePtr)
-        *imagePtr = image;
-    return CGImageCreate(image->width(), image->height(), 8, 32,
-                                        image->bytesPerLine(),
-                                        QCoreGraphicsPaintEngine::macGenericColorSpace(),
-                                        cgflags, dataProvider, 0, false, kCGRenderingIntentDefault);
-
-}
-
 void QCoreGraphicsPaintEngine::drawImage(const QRectF &r, const QImage &img, const QRectF &sr,
                                          Qt::ImageConversionFlags flags)
 {
@@ -1026,8 +989,7 @@ void QCoreGraphicsPaintEngine::drawImage(const QRectF &r, const QImage &img, con
     if (img.isNull() || state->compositionMode() == QPainter::CompositionMode_Destination)
         return;
 
-    const QImage *image;
-    QCFType<CGImageRef> cgimage = qt_mac_createCGImageFromQImage(img, &image);
+    QCFType<CGImageRef> cgimage = qt_mac_toCGImage(img);
     CGRect rect = CGRectMake(r.x(), r.y(), r.width(), r.height());
     if (QRectF(0, 0, img.width(), img.height()) != sr)
         cgimage = CGImageCreateWithImageInRect(cgimage, CGRectMake(sr.x(), sr.y(),