From: Dimitri Schoolwerth <dimitri.schoolwerth@gmail.com>
Date: Fri, 7 Jan 2011 08:48:43 +0000 (+0000)
Subject: Fixed saving PNG in wrong format sometimes.
X-Git-Url: https://git.saurik.com/wxWidgets.git/commitdiff_plain/b057ac075b504e160ac2571cd2c79171fc55f55d

Fixed saving PNG in wrong format sometimes.

When explicitly requesting saving as a palettised image but then later on that turns out to not be possible (or desired) the image would be marked as PNG_COLOR_TYPE_GRAY or PNG_COLOR_TYPE_GRAY_ALPHA. Simply set the colour type to RGB if this occurs also updated the unit test to catch this case.

This is similar to the fix in r66590 but that one was related to wxUSE_PALETTE == 0 cases.



git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66617 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---

diff --git a/src/common/imagpng.cpp b/src/common/imagpng.cpp
index f2f625c40e..f5f0d82924 100644
--- a/src/common/imagpng.cpp
+++ b/src/common/imagpng.cpp
@@ -772,12 +772,16 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos
     }
 #else
     bool bUsePalette = false;
+#endif // wxUSE_PALETTE
 
-    if (iColorType == wxPNG_TYPE_PALETTE)
+    /*
+    If saving palettised was requested but it was decided we can't use a
+    palette then reset the colour type to RGB.
+    */
+    if (!bUsePalette && iColorType == wxPNG_TYPE_PALETTE)
     {
         iColorType = wxPNG_TYPE_COLOUR;
     }
-#endif // wxUSE_PALETTE
 
     bool bUseAlpha = !bUsePalette && (bHasAlpha || bHasMask);
 
diff --git a/tests/image/image.cpp b/tests/image/image.cpp
index 53d9243199..8d7dae6ce1 100644
--- a/tests/image/image.cpp
+++ b/tests/image/image.cpp
@@ -1038,6 +1038,14 @@ void ImageTestCase::CompareSavedImage()
         }
     }
 
+    /*
+    Explicitly make known we want a palettised PNG. If we don't then this
+    particular image gets saved as a true colour image because there's an
+    alpha channel present and the PNG saver prefers to keep the alpha over
+    saving as a palettised image that has alpha converted to a mask.
+    */
+    expected8.SetOption(wxIMAGE_OPTION_PNG_FORMAT, wxPNG_TYPE_PALETTE);
+
     /*
     The image contains 256 indexed colours and needs another palette entry
     for storing the transparency index. This results in wanting 257 palette
@@ -1066,13 +1074,6 @@ void ImageTestCase::CompareSavedImage()
         red[paletteCount-2], green[paletteCount-2], blue[paletteCount-2]);
 
     expected8.SetPalette(newPal);
-    /*
-    Explicitly make known we want a palettised PNG. If we don't then this
-    particular image gets saved as a true colour image because there's an
-    alpha channel present and the PNG saver prefers to keep the alpha over
-    saving as a palettised image that has alpha converted to a mask.
-    */
-    expected8.SetOption(wxIMAGE_OPTION_PNG_FORMAT, wxPNG_TYPE_PALETTE);
 
     wxImage ref8 = expected8;