jcore/jx: fix JImage to correctly apply a mask for true color png's

libjcore/code/JCoreLibVersion.h

@@ -53,6 +53,9 @@ static const char* kCurrentJCoreLibVersionStr = "4.1.0";
 //	jListUtil:
 //		*** Removed JCompareIndices(), JCompareSizes(), JCompareCoordinates(),
 //			JCompareUInt64() in favor of <=>.
+//	JImage:
+//		Fixed ReadGD() to correctly apply a mask for true color png's.
+//		Added pure virtual CreateEmptyMask().
 
 // version 4.0.0:
 //	*** Upgraded to C++20

libjcore/code/JImage.cpp

@@ -318,6 +318,9 @@ JImage::ReadGD
 	{
 		PrepareForImageData();
 
+		auto* mask   = CreateEmptyMask();
+		bool setMask = false;
+
 		for (JCoordinate x=0; x<itsWidth; x++)
 		{
 			for (JCoordinate y=0; y<itsHeight; y++)
@@ -329,11 +332,28 @@ JImage::ReadGD
 						gdImageGreen(image, c) * kGDColorScale,
 						gdImageBlue (image, c) * kGDColorScale));
 				SetColor(x,y, color);
+
+				if ((!hasMask && gdImageAlpha(image, c) == 0) ||
+					( hasMask && c != maskColor))
+				{
+					mask->AddPixel(x,y);
+					setMask = true;
+				}
 			}
 		}
 
 		ImageDataFinished();
 
+		if (setMask)
+		{
+			SetMask(mask);
+		}
+		else
+		{
+			jdelete mask;
+			mask = nullptr;
+		}
+
 		gdImageDestroy(image);
 		image = nullptr;
 

libjcore/code/JImage.h

@@ -48,7 +48,9 @@ class JImage
 	virtual void		SetColor(const JCoordinate x, const JCoordinate y,
 								 const JColorID color) = 0;
 
-	virtual bool	GetMask(JImageMask** mask) const = 0;
+	virtual bool		GetMask(JImageMask** mask) const = 0;
+	virtual void		SetMask(JImageMask* mask) = 0;
+	virtual JImageMask*	CreateEmptyMask() const = 0;
 
 	JError	WriteGIF(const JString& fileName,
 					 const bool compressColorsToFit,

libjx/code/JXImage.cpp

@@ -708,6 +708,17 @@ JXImage::GetMask		// virtual
 	return itsMask != nullptr;
 }
 
+void
+JXImage::SetMask
+	(
+	JImageMask* mask
+	)
+{
+	JXImageMask* xmask = dynamic_cast<JXImageMask*>(mask);
+	assert( xmask != nullptr );
+	SetMask(xmask);
+}
+
 void
 JXImage::SetMask
 	(
@@ -728,6 +739,13 @@ JXImage::ClearMask()
 	itsMask = nullptr;
 }
 
+JImageMask*
+JXImage::CreateEmptyMask()
+	const
+{
+	return jnew JXImageMask(itsDisplay, GetWidth(), GetHeight(), false);
+}
+
 /******************************************************************************
  Draw
 
@@ -1138,7 +1156,7 @@ JXImage::SetImageData
 	const JSize			colorCount,
 	const JColorID*		colorTable,
 	unsigned short**	imageData,
-	const bool		hasMask,
+	const bool			hasMask,
 	const unsigned long	maskColor
 	)
 {

libjx/code/JXImage.h

@@ -79,11 +79,13 @@ class JXImage : public JImage, public virtual JBroadcaster
 	JXDisplay*	GetDisplay() const;
 	JSize		GetDepth() const;
 
-	bool	HasMask() const;
-	bool	GetMask(JImageMask** mask) const override;
-	bool	GetMask(JXImageMask** mask) const;
-	void	SetMask(JXImageMask* mask);
-	void	ClearMask();
+	bool		HasMask() const;
+	bool		GetMask(JImageMask** mask) const override;
+	bool		GetMask(JXImageMask** mask) const;
+	void		SetMask(JImageMask* mask) override;
+	void		SetMask(JXImageMask* mask);
+	void		ClearMask();
+	JImageMask*	CreateEmptyMask() const override;
 
 	void	Draw(const Drawable drawable, JXGC* gc,
 				 const JRect& srcRect, const JRect& destRect) const;

libjx/code/JXImageMask.cpp

@@ -29,7 +29,7 @@ JXImageMask::JXImageMask
 	JXDisplay*			display,
 	const JCoordinate	width,
 	const JCoordinate	height,
-	const bool		filled
+	const bool			filled
 	)
 	:
 	JXImage(display, width, height,

libjx/code/JXImage_JPEG.cpp

@@ -27,7 +27,6 @@ JXImage::CreateFromJPEG
 	)
 {
 	*image = jnew JXImage(display);
-	assert( *image != nullptr );
 
 	const JError err = (**image).ReadJPEG(fileName);
 

libjx/code/JXImage_PNG.cpp

@@ -27,7 +27,6 @@ JXImage::CreateFromPNG
 	)
 {
 	*image = jnew JXImage(display);
-	assert( *image != nullptr );
 
 	const JError err = (**image).ReadPNG(fileName);
 

libjx/testui/testjx.jcc

@@ -271,6 +271,7 @@ T "./" "&make_default ; /bin/sh -c 'JMM_INITIALIZE=yes JMM_SHRED=yes JMM_RECORD_
 T "./" "&make_default ; /bin/sh -c 'JMM_INITIALIZE=yes JMM_SHRED=yes JMM_RECORD_ALLOCATED=yes JMM_PRINT_EXIT_STATS=yes ./$program --debug-ftc-vert' ; echo \"Remaining memory should be 1008 bytes\"" "" FFFTTFF "Debug FTC Vert" "Shift-F11" "" T
 T "./" "testjx -MDI" "" FFFFTTF "" "" "$svHlVFP`<D)#Cpy3gRi::CBCommandManager" F
 T "./" "testjx --pseudotranslate" "" FFFFTTF "" "" "$svHlVFP`<D)#Cpy3gRi::CBCommandManager" F
+T "./" "make jx.test.skip=true -kw" "" TFTTTFF "" "" "" F
 F
 # build settings
 1