text.c

Ming is a library for generating Macromedia Flash files (.swf), written in C, and includes useful ut

short
SWFText_getScaledAscent(SWFText text)
{
	SWFFont font;
	int height;

	if(text->currentRecord == NULL)
		return -1;

	font = text->currentRecord->font.font;
	height = text->currentRecord->height;
	return SWFFont_getScaledAscent(font) * height / 1024;
}


short
SWFText_getScaledDescent(SWFText text)
{
	SWFFont font;
	int height;

	if(text->currentRecord == NULL)
		return -1;

	font = text->currentRecord->font.font;
	height = text->currentRecord->height;
	return SWFFont_getScaledDescent(font) * height / 1024;
}


short
SWFText_getScaledLeading(SWFText text)
{
	SWFFont font = text->currentRecord->font.font;
	int height = text->currentRecord->height;

	return SWFFont_getScaledLeading(font) * height / 1024;
}

void 
SWFText_setFont(SWFText text, SWFFont font)
{
	SWFTextRecord textRecord = text->currentRecord;
	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	textRecord->flags |= SWF_TEXT_HAS_FONT;
	textRecord->font.font = font;
}


void
SWFText_setScaledHeight(SWFText text, int height)
{
	SWFTextRecord textRecord = text->currentRecord;

	if ( textRecord == NULL ||
			 (textRecord->string != NULL && height != textRecord->height) )
	{
		textRecord = SWFText_addTextRecord(text);
	}

	textRecord->flags |= SWF_TEXT_HAS_FONT;
	textRecord->height = height;
}


void
SWFText_setScaledSpacing(SWFText text, int spacing)
{
	SWFTextRecord textRecord = text->currentRecord;

	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	textRecord->spacing = spacing;
}


void
SWFText_setColor(SWFText text, byte r, byte g, byte b, byte a)
{
	SWFTextRecord textRecord = text->currentRecord;

	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	textRecord->flags |= SWF_TEXT_HAS_COLOR;
	textRecord->r = r;
	textRecord->g = g;
	textRecord->b = b;
	textRecord->a = a;
}


void
SWFText_scaledMoveTo(SWFText text, int x, int y)
{
	SWFTextRecord textRecord = text->currentRecord;

	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	if ( x != 0 )
	{
		textRecord->flags |= SWF_TEXT_HAS_X;
		textRecord->x = x;
	}

	if ( y != 0 )
	{
		textRecord->flags |= SWF_TEXT_HAS_Y;
		textRecord->y = y;
	}
}


/* adds textrecord type 0 to output */
/* font defn is normalized to height 1024 */
/* glyph codes changed to (correct) character codes by Raff */

void
SWFText_addWideString(SWFText text, const unsigned short* widestring,
											int len, int* advance)
{
	SWFTextRecord textRecord = text->currentRecord;

	/* marginally sloppy to tack on a new record,
		 but I don't want to deal with concats */

	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	if ( textRecord->font.font == NULL )
		SWF_error("font must be set before calling addString");

	textRecord->advance = advance;
	textRecord->strlen = len;
	textRecord->string = (unsigned short*)malloc(sizeof(unsigned short) * len);

	/* If malloc failed, return early */
	if (NULL == textRecord->string)
	{
		destroySWFTextRecord(textRecord);
		return;
	}

	memcpy(textRecord->string, widestring, sizeof(unsigned short) * len);
}


void
SWFText_addUTF8String(SWFText text, const char* string, int* advance)
{
	unsigned short* widestring;
	int len = UTF8ExpandString(string, &widestring);

	SWFTextRecord textRecord = text->currentRecord;

	/* marginally sloppy to tack on a new record,
		 but I don't want to deal with concats */

	if ( textRecord == NULL || textRecord->string != NULL )
		textRecord = SWFText_addTextRecord(text);

	/* If SWFText_addTextRecord() failed, return early */
	if (NULL == textRecord)
		return;

	if ( textRecord->font.font == NULL )
		SWF_error("font must be set before calling addString");

	textRecord->advance = advance;
	textRecord->strlen = len;
	textRecord->string = widestring;
}


void
SWFText_addString(SWFText text, const char* string, int* advance)
{
	int len = strlen(string);
	int i;
	unsigned short* widestring = (unsigned short*) malloc(len * sizeof(unsigned short) );

	/* If malloc() failed, return early */
	if (NULL == widestring)
		return;

	for ( i = 0; i < len; ++i )
		widestring[i] = string[i] & 0xff;
	SWFText_addWideString(text, widestring, len, advance);
	free(widestring);
}


static void
SWFTextRecord_computeAdvances(SWFTextRecord textRecord)
{
	int i;
	int len = textRecord->strlen;
	unsigned short* widestring = textRecord->string;
	unsigned short glyph;

	SWFFontCharacter fontchar = textRecord->font.fontchar;
	SWFFont font = SWFFontCharacter_getFont(fontchar);

	if(!len) return;	// do not try to calculate 1st char of null string

	/* compute advances (spacing) from spacing, advance and kern table */
	if ( textRecord->advance == NULL )
	{
		textRecord->advance = (int*)malloc(sizeof(int) * len);
		/* If malloc() failed, return early */
		if (NULL == textRecord->advance)
			return;

		textRecord->advAllocated = 1;
		memset(textRecord->advance, 0, sizeof(int) * len);
	}

	glyph = SWFFontCharacter_getGlyphCode(fontchar, widestring[0]);

	for ( i=0; i<len; ++i )
	{
		int adv;
		unsigned short nextglyph;

		adv = SWFFont_getCharacterAdvance(font, (unsigned short)glyph);
		adv += textRecord->spacing;

		/* get kerning from font's kern table */

		if ( i < len-1 )
		{	nextglyph = SWFFontCharacter_getGlyphCode(fontchar, widestring[i+1]);
			adv += SWFFont_getCharacterKern(font, glyph, nextglyph);
			glyph = nextglyph;
		}

		if ( textRecord->advance != NULL )
			adv += textRecord->advance[i];

		textRecord->advance[i] = adv * textRecord->height / 1024;

		textRecord->nAdvanceBits = max(textRecord->nAdvanceBits,
			SWFOutput_numSBits(textRecord->advance[i]));

	}
}


/* turn textRecord list into output code */

void
SWFText_resolveCodes(SWFText text)
{
	SWFTextRecord textRecord, oldRecord;
	SWFOutput out = text->out;
	int nGlyphBits = 0;
	int len, i;
	int curX = 0, curY = 0, curH = 0;

	textRecord = text->initialRecord;

	while ( textRecord != NULL )
	{
		SWFTextRecord_computeAdvances(textRecord);

		text->nAdvanceBits = max(text->nAdvanceBits, textRecord->nAdvanceBits);

		if ( textRecord->flags & SWF_TEXT_HAS_FONT )
		{	
			int fontGlyphs = SWFFontCharacter_getNGlyphs(textRecord->font.fontchar);
			nGlyphBits = max(nGlyphBits, SWFOutput_numBits(fontGlyphs-1));
		}

		textRecord = textRecord->next;
	}

	textRecord = text->initialRecord;

	while ( textRecord != NULL )
	{
		oldRecord = textRecord;

		if ( textRecord->string == NULL || textRecord->strlen == 0 )
		{
			textRecord = textRecord->next;
			destroySWFTextRecord(oldRecord);
			continue;
		}

		SWFOutput_byteAlign(out);

		/* Raff says the spec lies- there's always a change record, even if
			 it's empty, and the string record length is the full 8 bits. */

		SWFOutput_writeUInt8(out, textRecord->flags | SWF_TEXT_STATE_CHANGE);

		if ( textRecord->flags & SWF_TEXT_HAS_FONT )
			SWFOutput_writeUInt16(out, CHARACTERID(textRecord->font.fontchar));

		if ( textRecord->flags & SWF_TEXT_HAS_COLOR )
		{
			SWFOutput_writeUInt8(out, textRecord->r);
			SWFOutput_writeUInt8(out, textRecord->g);
			SWFOutput_writeUInt8(out, textRecord->b);

			if ( BLOCK(text)->type == SWF_DEFINETEXT2 )
				SWFOutput_writeUInt8(out, textRecord->a);
		}

		if ( textRecord->flags & SWF_TEXT_HAS_X )
		{
			SWFOutput_writeUInt16(out, textRecord->x);
			curX = textRecord->x;
		}

		if ( textRecord->flags & SWF_TEXT_HAS_Y )
		{
			SWFOutput_writeUInt16(out, textRecord->y);
			curY = textRecord->y;
		}

		if ( textRecord->flags & SWF_TEXT_HAS_FONT )
		{
			SWFOutput_writeUInt16(out, textRecord->height);
			curH = textRecord->height;
		}

		/* record type 0: string data */

		len = textRecord->strlen;

		if ( len >= 256 )
			SWF_error("Found text record >= 256 characters!");

		SWFOutput_writeUInt8(out, len);

		SWFFontCharacter fontchar = textRecord->font.fontchar;
		SWFFont font = SWFFontCharacter_getFont(fontchar);

		if ( font == NULL )
			SWF_error("Couldn't find font");

		for ( i=0; i<len; ++i )
		{
			SWFRect glyphBounds;
			int minX, maxX, minY, maxY;

			unsigned short code =
				SWFFontCharacter_getGlyphCode(fontchar, textRecord->string[i]);

			glyphBounds = SWFFont_getGlyphBounds(font, code);
			SWFRect_getBounds(glyphBounds, &minX, &maxX, &minY, &maxY);

			SWFOutput_writeBits(out, textRecord->string[i],	nGlyphBits);
			SWFOutput_writeBits(out, textRecord->advance[i], text->nAdvanceBits);

			if ( CHARACTER(text)->bounds )
			{
				SWFRect_includePoint(CHARACTER(text)->bounds, curX + minX * curH / 1024, 
				                     curY + minY * curH / 1024, 0);
				SWFRect_includePoint(CHARACTER(text)->bounds, curX + maxX * curH / 1024, 
				                     curY + maxY * curH / 1024, 0);
			}
			else
			{
				CHARACTER(text)->bounds = newSWFRect(curX + minX * curH /1024, 
					curX + maxX * curH /1024, curY + minY * curH /1024, 
					curY + maxY * curH /1024);
			}

			if ( textRecord->advance != NULL )
				curX += textRecord->advance[i];
		}
		textRecord = textRecord->next;
		destroySWFTextRecord(oldRecord);
	}
	SWFOutput_writeUInt8(out, 0); /* end text records */

	text->nGlyphBits = nGlyphBits;
	text->initialRecord = NULL;
	text->currentRecord = NULL;
}


/*
 * Local variables:
 * tab-width: 2
 * c-basic-offset: 2
 * End:
 */