throw exception using Face#GetSfntName(uint idx) and some method such as Face#GetPSFontInfo(), Face#GetPostscriptName()

[nghiaiosdev]

when i using following codes, Visual Studio throw exceptio with messege: "An unhandled exception of type 'System.AccessViolationException' occurred in System.Windows.Forms.dll
Additional information: Attempted to read or write protected memory. This is often an indication that other memory is corrupt."

Library lib = new Library();
Face face = new Face(lib, "Slabo27px-Regular.ttf");
int sfntCount = (int)face.GetSfntNameCount();
for (int i = 0; i < sfntCount; i++)
{
SfntName sfnt = face.GetSfntName(0);
}

And anyone can fix it? Thanks you so much.

[HinTak]

Your usage. Try this instead:

Face face = lib.NewFace("Slabo27px-Regular.ttf",0);

That said, maybe new Face(lib,...) should be made to work too...

[Robmaister]

@HinTak The constructors are indeed overloaded. It's the primary method of creating new objects. lib.NewFace just calls the constructor.

@eitguide emailed me earlier with this and one other exception, the second one being a bug in Face.GetPSFontInfo where there is one extra level of indirection in the out parameter. This would lead me to believe I've made a similar mistake with the SFNT API. Both should be relatively simple fixes, and I have a few minutes of spare time right now, so expect a fix in a few minutes.

[Robmaister]

Also found that Face.GetPSFontPrivate had an error. I'll do a pass through the API later to see if there are any other areas where this bug exists.

[nghianguyeniosdev]

Thank you so much. If I detect any bugs in lib, I will feedback for you. Thanks.

[Robmaister]

Digging deeper, I found that the SfntName.String property can be a string of any format, so I added some overloads.

To maintain backwards compatibility, String returns a UTF-16 encoded string, StringAnsi returns an ANSI encoded string, and StringPtr returns the IntPtr to allow for any other encoding format. This commit should be pushed up in a minute

[Robmaister]

As for the exception in GetPSFontInto and GetPSPrivate, these are not problems in SharpFont. You are trying to access PostScript data for a TrueType font.

The exception I got from a sample program was a FreeTypeException for "Invalid argument", which in this case means the font does not support the function you tried to call on it. I downloaded a separate, free PS Type1 font to test this on, and the values now appear to be reasonable. Here is the test case I'm using:

static void Main(string[] args)
{
	Library lib = new Library();
	Face face = new Face(lib, "Slabo27px-Regular.ttf");
	uint sfntCount = face.GetSfntNameCount();
	for (uint i = 0; i < sfntCount; i++)
	{
		SfntName sfnt = face.GetSfntName(i);
	}

	face = new Face(lib, "ugqb.pfa");
	FontInfo info = face.GetPSFontInfo();
	string name = face.GetPostscriptName();
}