Binary Tips

This page is about editing and working with Binary data (Images, sound, etc) passed from FileMaker to your plugin.

Binary Public Functions

• BinaryData &operator = ( const BinaryData &source )
• bool operator == ( const BinaryData &compareData ) const
• bool operator != ( const BinaryData &compareData ) const
• int GetCount () const
• int GetIndex ( const QuadChar& dataType ) const
• ulong GetTotalSize () const
• void GetType ( int index, QuadChar& dataType ) const
• ulong GetSize ( int index ) const
• errcode GetData ( int index, ulong offset, ulong amount, void *buffer ) const

• errcode Add ( const QuadChar& dataType, ulong amount, void *buffer )
• bool Remove ( const QuadChar& dataType )
• void RemoveAll ()

• errcode GetFNAMData ( Text &filepathlist ) const
• errcode AddFNAMData ( const Text &filepathlist )
• errcode GetSIZEData ( short &width, short &height ) const
• errcode AddSIZEData ( short width, short height )

• void operator delete ( void *obj )

• BinaryDataAutoPtr ()
• BinaryDataAutoPtr ( const BinaryData &sourceData )

Example Binary Functions

The following example code shows how to create a bitmap image, convert it to PNG and return to FileMaker

FMX_PROC(fmx::errcode) Do_Graphic(short /* funcId */, const fmx::ExprEnv& /* environment */, const fmx::DataVect& dataVect, fmx::Data&  results )
{
	
	fmx::errcode	err = 0;
	bool            haveImage = false;
	fmx::QuadCharAutoPtr	png('P', 'N', 'G', 'f');
	fmx::BinaryDataAutoPtr	outImage;

    
	long pixelsWide = 300;
	long pixelsHigh = 150;
 
	long size = 0;
	unsigned char *	outBuffer = returnGraphicImage(pixelsWide, pixelsHigh, &size);
	if( outBuffer != NULL )
	{
		
		err = outImage->Add ( *png, size, outBuffer );
		if (err == 0)
		{
			fmx::TextAutoPtr	temp;
			temp->Assign("Picture.png");
			const fmx::Text&  name	=	*temp;
			err = outImage->AddFNAMData( name );			// so FileMaker has a name for our image if the user tries to save it or external storage is used
			
			err = outImage->AddSIZEData( pixelsWide, pixelsHigh );			// all images must have a size specified
			haveImage = ( err == 0 );
			if( haveImage )	results.SetBinaryData ( *outImage );
		}
		
		delete [] outBuffer;
	}

	return err;
}

The 'returnGraphicImage' function for Mac:

#if defined(FMX_MAC_TARGET)
unsigned char * returnGraphicImage( long width, long height, long *outSize )
{
	#define BYTES_PER_PIXEL	4

	CFMutableDataRef	imgData = CFDataCreateMutable( kCFAllocatorDefault, 0);
	if( imgData == NULL )	return NULL;
	
	CGImageDestinationRef	destRef = CGImageDestinationCreateWithData(imgData, kUTTypePNG, 1, NULL);
	if( destRef == NULL )	{ CFRelease( imgData );	return NULL; }

	// create an image from the layer
	void	*buffer = malloc(width * height * BYTES_PER_PIXEL);
	if( buffer == NULL )	{ CFRelease( destRef );	CFRelease( imgData );	return NULL; }
	memset(&buffer, 0, sizeof(buffer));


	CGColorSpaceRef	colorSpace = CGColorSpaceCreateWithName(kCGColorSpaceGenericRGB);
	CGContextRef		context = CGBitmapContextCreate (buffer, width, height, 8, width * BYTES_PER_PIXEL, colorSpace, kCGImageAlphaPremultipliedLast);
	CGColorSpaceRelease( colorSpace );

	if( context == NULL )	{ CFRelease( destRef );	CFRelease( imgData );	free( buffer );	return NULL; }
	

	// Open the image area for drawing
	CGContextSaveGState(context);
	CGRect	rect = CGRectMake(0, 0, width, height);						// RECT representing the area available for drawing to.
	// ---------------------------------------------------------------------------------------------------------------

	CGContextSetRGBStrokeColor(context, 1, 0, 0, 1);					// Draw a 'Red' frame around our image.
	CGContextStrokeRectWithWidth(context, rect, 6);

	CGContextSelectFont(context, "Verdana", 12, kCGEncodingMacRoman);			// Add some text to our image
	CGContextSetAllowsAntialiasing(context, false);
	CGContextSetCharacterSpacing(context, 1.0);
	CGContextSetTextDrawingMode(context, kCGTextFill);
	CGContextShowTextAtPoint(context, 50.0, 50.0, "Hello and Welcome", 17);


	// ---------------------------------------------------------------------------------------------------------------

	CGImageRef	image		= CGBitmapContextCreateImage(context);			// We have finished drawing the image
	CGContextRestoreGState(context);

 	CGImageDestinationAddImage(destRef, image, NULL);					// Convert the image to PNG
	CGImageDestinationFinalize(destRef);
	
	CGContextRelease(context);
	CFRelease(destRef);									// have finished with destRef - our image should now be in 'imgData'
	free(buffer);										// have finished with the image buffer now too

	unsigned char * outBuffer = NULL;
	long size = (long)CFDataGetLength(imgData);
	if( size > 0 )
	{
		outBuffer = new unsigned char [ size ];
		
		if( outBuffer != NULL )		CFDataGetBytes( imgData, CFRangeMake(0, size), outBuffer );
	}
	
	CFRelease(imgData);

	*outSize = size;	// return the size of our created buffer
	return outBuffer;	// and the buffer itself
}
#endif