X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=ttf2png.c;h=ae559b106ee14290666ccbf85a79565bd3ca4911;hb=4fd8c77456f73fb6b30d4ed7125e3990e70a6eed;hp=c77cd5889509248390bd80dbeee0606586719c96;hpb=a63e33344928b7f767b97aced995a84ad9b53de0;p=ttf2png.git

diff --git a/ttf2png.c b/ttf2png.c
index c77cd58..ae559b1 100644
--- a/ttf2png.c
+++ b/ttf2png.c
@@ -28,34 +28,48 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 typedef struct sImage
 {
 	unsigned w, h;
-	char     *data;
+	char *data;
 } Image;
 
 typedef struct sGlyph
 {
+	unsigned index;
 	unsigned code;
-	Image    image;
+	Image image;
 	unsigned x, y;
-	int      offset_x;
-	int      offset_y;
-	int      advance;
+	int offset_x;
+	int offset_y;
+	int advance;
 } Glyph;
 
+typedef struct sKerning
+{
+	unsigned left_code;
+	unsigned right_code;
+	int distance;
+} Kerning;
+
 typedef struct sFont
 {
 	unsigned size;
-	int      ascent;
-	int      descent;
+	int ascent;
+	int descent;
 	unsigned n_glyphs;
-	Glyph    *glyphs;
-	Image    image;
+	Glyph *glyphs;
+	unsigned n_kerning;
+	Kerning *kerning;
+	Image image;
 } Font;
 
+void usage(void);
+int convert_numeric_option(char, int);
+void convert_code_point_range(char, int *, int *);
+void convert_size(char, int *, int *);
 unsigned round_to_pot(unsigned);
-void usage();
-void init_font(Font *, FT_Face, unsigned, unsigned, int);
-void render_grid(Font *, unsigned, unsigned, unsigned, int);
-void render_packed(Font *);
+void *alloc_image_data(size_t, size_t);
+int init_font(Font *, FT_Face, unsigned, unsigned, int);
+int render_grid(Font *, unsigned, unsigned, unsigned, int);
+int render_packed(Font *, unsigned, unsigned);
 int save_defs(const char *, const Font *);
 int save_png(const char *, const Image *, char);
 
@@ -64,23 +78,25 @@ char verbose = 0;
 int main(int argc, char **argv)
 {
 	char *fn;
-	int  begin = 0;
-	int  end = 255;
-	int  size = 10;
-	int  cpl = 0;
-	int  cellw = 0;
-	int  cellh = 0;
+	int begin = 0;
+	int end = 255;
+	int size = 10;
+	int cpl = 0;
+	int cellw = 0;
+	int cellh = 0;
 	char autohinter = 0;
 	char seq = 0;
 	char alpha = 0;
 	char invert = 0;
 	char pack = 0;
+	int margin = 0;
+	int padding = 1;
 
 	FT_Library freetype;
-	FT_Face    face;
+	FT_Face face;
 
-	int  err;
-	int  i;
+	int err;
+	int i;
 
 	char *out_fn = "font.png";
 	char *def_fn = NULL;
@@ -93,63 +109,21 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:pi")) != -1)
+	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:pim:n:")) != -1)
 	{
-		char *ptr;
-		int  temp;
 		switch(i)
 		{
 		case 'r':
-			if(!strcmp(optarg, "all"))
-			{
-				begin = 0;
-				end = 0x110000;
-			}
-			else
-			{
-				if(!isdigit(optarg[0]))
-					temp = -1;
-				else
-				{
-					temp = strtol(optarg, &ptr, 0);
-					if(ptr[0]!=',' || !isdigit(ptr[1]))
-						temp = -1;
-				}
-				if(temp<0)
-				{
-					printf("Not a valid range: %s\n", optarg);
-					exit(1);
-				}
-				else
-				{
-					begin = temp;
-					end = strtol(ptr+1, NULL, 0);
-				}
-			}
+			convert_code_point_range('r', &begin, &end);
 			break;
 		case 's':
-			size = strtol(optarg, NULL, 0);
+			size = convert_numeric_option('s', 1);
 			break;
 		case 'l':
-			cpl = strtol(optarg, NULL, 0);
+			cpl = convert_numeric_option('l', 1);
 			break;
 		case 'c':
-			if(!strcmp(optarg, "auto"))
-			{
-				cellw = 0;
-				cellh = 0;
-			}
-			else if(!strcmp(optarg, "autorect"))
-			{
-				cellw = 0;
-				cellh = 1;
-			}
-			else
-			{
-				cellw = strtol(optarg, &ptr, 0);
-				if(ptr[0]=='x' && isdigit(ptr[1]))
-					cellh = strtol(ptr+1, NULL, 0);
-			}
+			convert_size('c', &cellw, &cellh);
 			break;
 		case 'o':
 			out_fn = optarg;
@@ -179,6 +153,12 @@ int main(int argc, char **argv)
 		case 'i':
 			invert = 1;
 			break;
+		case 'm':
+			margin = convert_numeric_option('m', 0);
+			break;
+		case 'n':
+			padding = convert_numeric_option('n', 0);
+			break;
 		}
 	}
 	if(!strcmp(out_fn, "-"))
@@ -223,23 +203,33 @@ int main(int argc, char **argv)
 	}
 
 	font.size = size;
-	init_font(&font, face, begin, end, autohinter);
+	err = init_font(&font, face, begin, end, autohinter);
+	if(err)
+		return 1;
+
 	if(pack)
-		render_packed(&font);
+		err = render_packed(&font, margin, padding);
 	else
-		render_grid(&font, cellw, cellh, cpl, seq);
+		err = render_grid(&font, cellw, cellh, cpl, seq);
+	if(err)
+		return 1;
+
 	if(invert)
 	{
-		for(i=0; i<font.image.w*font.image.h; ++i)
+		for(i=0; (unsigned)i<font.image.w*font.image.h; ++i)
 			font.image.data[i] = 255-font.image.data[i];
 	}
-	save_png(out_fn, &font.image, alpha);
+	err = save_png(out_fn, &font.image, alpha);
+	if(err)
+		return 1;
+
 	if(def_fn)
 		save_defs(def_fn, &font);
 
-	for(i=0; i<font.n_glyphs; ++i)
+	for(i=0; (unsigned)i<font.n_glyphs; ++i)
 		free(font.glyphs[i].image.data);
 	free(font.glyphs);
+	free(font.kerning);
 	free(font.image.data);
 
 	FT_Done_Face(face);
@@ -248,6 +238,107 @@ int main(int argc, char **argv)
 	return 0;
 }
 
+void usage(void)
+{
+	printf("ttf2png 1.1 - True Type Font to PNG converter\n"
+		"Copyright (c) 2004-2018  Mikko Rasa, Mikkosoft Productions\n"
+		"Distributed under the GNU General Public License\n\n");
+
+	printf("Usage: ttf2png [options] <TTF file>\n\n");
+
+	printf("Accepted options (default values in [brackets])\n"
+		"  -r  Range of code points to convert [0,255]\n"
+		"  -s  Font size to use, in pixels [10]\n"
+		"  -l  Number of glyphs to put in one line [auto]\n"
+		"  -c  Glyph cell size, in pixels (grid mode only) [auto]\n"
+		"  -o  Output file name (or - for stdout) [font.png]\n");
+	printf("  -a  Force autohinter\n"
+		"  -t  Render glyphs to alpha channel\n"
+		"  -i  Invert colors of the glyphs\n"
+		"  -v  Increase the level of verbosity\n"
+		"  -e  Use cells in sequence, without gaps (grid mode only)\n"
+		"  -p  Pack the glyphs tightly instead of in a grid\n"
+		"  -m  Margin around image edges (packed mode only) [0]\n"
+		"  -n  Padding between glyphs (packed mode only) [1]\n"
+		"  -d  File name for writing glyph definitions\n"
+		"  -h  Print this message\n");
+}
+
+int convert_numeric_option(char opt, int min_value)
+{
+	int value;
+	char *ptr;
+
+	value = strtol(optarg, &ptr, 0);
+	if(value<min_value || *ptr)
+	{
+		printf("Invalid option argument in -%c %s\n", opt, optarg);
+		exit(1);
+	}
+
+	return value;
+}
+
+void convert_code_point_range(char opt, int *begin, int *end)
+{
+	char *ptr;
+
+	if(!strcmp(optarg, "all"))
+	{
+		*begin = 0;
+		*end = 0x10FFFF;
+		return;
+	}
+
+	*begin = strtol(optarg, &ptr, 0);
+	if(*begin>0 && *ptr==',')
+	{
+		*end = strtol(ptr+1, &ptr, 0);
+		if(*end>0 && !*ptr)
+			return;
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
+void convert_size(char opt, int *width, int *height)
+{
+	char *ptr;
+
+	if(!strcmp(optarg, "auto"))
+	{
+		*width = 0;
+		*height = 0;
+		return;
+	}
+	else if(!strcmp(optarg, "autorect"))
+	{
+		*width = 0;
+		*height = 1;
+		return;
+	}
+
+	*width = strtol(optarg, &ptr, 0);
+	if(*width>0)
+	{
+		if(*ptr=='x')
+		{
+			*height = strtol(ptr+1, &ptr, 0);
+			if(*height>0 && !*ptr)
+				return;
+		}
+		else if(!*ptr)
+		{
+			*height = *width;
+			return;
+		}
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
 unsigned round_to_pot(unsigned n)
 {
 	n -= 1;
@@ -260,31 +351,33 @@ unsigned round_to_pot(unsigned n)
 	return n+1;
 }
 
-void usage()
+void *alloc_image_data(size_t a, size_t b)
 {
-	printf("ttf2png - True Type Font to PNG converter\n"
-		"Copyright (c) 2004-2008  Mikko Rasa, Mikkosoft Productions\n"
-		"Distributed under the GNU General Public License\n\n"
-		"Usage: ttf2png [options] <TTF file>\n\n"
-		"Accepted options (default values in [brackets])\n"
-		"  -r  Range of characters to convert in the format low,high [0,255]\n"
-		"  -s  Font size to use, in pixels [10]\n"
-		"  -l  Number of characters to put in one line [auto]\n"
-		"  -c  Character cell size, in pixels [auto]\n"
-		"  -o  Output file name (or - for stdout) [font.png]\n"
-		"  -a  Force autohinter\n"
-		"  -t  Render font to alpha channel\n"
-		"  -i  Invert colors of the glyphs\n"
-		"  -v  Increase the level of verbosity\n"
-		"  -e  Use cells in sequence, rather than by code\n"
-		"  -p  Pack the glyphs tightly instead of in a grid\n"
-		"  -d  Write a definition to the given file\n"
-		"  -h  Print this message\n");
+	void *ptr;
+
+	/* Carry out the multiplication manually so we can check for overflow. */
+	while(b>1)
+	{
+		size_t c = a;
+		a *= 2;
+		if(b&1)
+			a += c;
+		if(a<c)
+		{
+			fprintf(stderr, "Cannot allocate %lu kbytes of memory for image\n", (unsigned long)(c/1024*b));
+			return NULL;
+		}
+		b /= 2;
+	}
+	ptr = malloc(a);
+	if(!ptr)
+		fprintf(stderr, "Cannot allocate %lu kbytes of memory for image\n", (unsigned long)(a/1024*b));
+	return ptr;
 }
 
-void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int autohinter)
+int init_font(Font *font, FT_Face face, unsigned first, unsigned last, int autohinter)
 {
-	unsigned i;
+	unsigned i, j;
 	unsigned size = 0;
 
 	font->ascent = (face->size->metrics.ascender+63)>>6;
@@ -300,11 +393,11 @@ void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int auto
 	font->glyphs = NULL;
 	for(i=first; i<=last; ++i)
 	{
-		unsigned  n;
+		unsigned n;
 		FT_Bitmap *bmp = &face->glyph->bitmap;
-		int       x, y;
-		int       flags = 0;
-		Glyph     *glyph;
+		unsigned x, y;
+		int flags = 0;
+		Glyph *glyph;
 
 		n = FT_Get_Char_Index(face, i);
 		if(!n)
@@ -331,14 +424,23 @@ void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int auto
 		}
 
 		glyph = &font->glyphs[font->n_glyphs++];
+		glyph->index = n;
 		glyph->code = i;
 		glyph->image.w = bmp->width;
 		glyph->image.h = bmp->rows;
 		glyph->image.data = (char *)malloc(bmp->width*bmp->rows);
+		if(!glyph->image.data)
+		{
+			fprintf(stderr, "Cannot allocate %d bytes of memory for glyph\n", bmp->width*bmp->rows);
+			return -1;
+		}
 		glyph->offset_x = face->glyph->bitmap_left;
 		glyph->offset_y = face->glyph->bitmap_top-bmp->rows;
 		glyph->advance = (int)(face->glyph->advance.x+32)/64;
 
+		/* Copy the glyph image since FreeType uses a global buffer, which would
+		be overwritten by the next glyph.  Negative pitch means the scanlines
+		start from the bottom. */
 		if(bmp->pitch<0)
 		{
 			for(y=0; y<bmp->rows; ++y) for(x=0; x<bmp->width; ++x)
@@ -353,23 +455,49 @@ void init_font(Font *font, FT_Face face, unsigned first, unsigned last, int auto
 
 	if(verbose>=1)
 		printf("Loaded %u glyphs\n", font->n_glyphs);
+
+	size = 0;
+	font->n_kerning = 0;
+	font->kerning = NULL;
+	for(i=0; i<font->n_glyphs; ++i) for(j=0; j<font->n_glyphs; ++j)
+		if(j!=i)
+		{
+			FT_Vector kerning;
+			FT_Get_Kerning(face, font->glyphs[i].index, font->glyphs[j].index, FT_KERNING_DEFAULT, &kerning);
+
+			/* FreeType documentation says that vertical kerning is practically
+			never used, so we ignore it. */
+			if(kerning.x)
+			{
+				Kerning *kern;
+
+				if(font->n_kerning>=size)
+				{
+					size += 16;
+					font->kerning = (Kerning *)realloc(font->kerning, size*sizeof(Kerning));
+				}
+
+				kern = &font->kerning[font->n_kerning++];
+				kern->left_code = font->glyphs[i].code;
+				kern->right_code = font->glyphs[j].code;
+				kern->distance = kerning.x/64;
+			}
+		}
+
+	if(verbose>=1)
+		printf("Loaded %d kerning pairs\n", font->n_kerning);
+
+	return 0;
 }
 
-void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int seq)
+int render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int seq)
 {
 	unsigned i;
-	int      top = 0, bot = 0;
+	int top = 0, bot = 0;
 	unsigned first, last;
 	unsigned maxw = 0, maxh = 0;
 
-	for(i=1;; i<<=1)
-	{
-		first = font->glyphs[0].code&~(i-1);
-		last = first+i-1;
-		if(last>=font->glyphs[font->n_glyphs-1].code)
-			break;
-	}
-
+	/* Find extremes of the glyph images. */
 	for(i=0; i<font->n_glyphs; ++i)
 	{
 		int y;
@@ -387,6 +515,7 @@ void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int s
 
 	if(cellw==0)
 	{
+		/* Establish a large enough cell to hold all glyphs in the range. */
 		int square = (cellh==cellw);
 		cellw = maxw;
 		cellh = top-bot;
@@ -404,35 +533,42 @@ void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int s
 		printf("Max size:  %u x %u\n", maxw, maxh);
 		printf("Y range:   [%d %d]\n", bot, top);
 		printf("Cell size: %u x %u\n", cellw, cellh);
-		if(maxw>cellw || top-bot>cellh)
+		if(maxw>cellw || (unsigned)(top-bot)>cellh)
 			fprintf(stderr, "Warning: character size exceeds cell size\n");
 	}
 
 	if(cpl==0)
 	{
-		unsigned count = (seq ? font->n_glyphs : last-first+1);
+		/* Determine number of characters per line, trying to fit all the glyphs
+		in a square image. */
 		for(i=1;; i<<=1)
 		{
 			cpl = i/cellw;
-			if(cpl>0 && (count+cpl-1)/cpl*cellh<=cpl*cellw)
+			if(cpl>0 && font->n_glyphs/cpl*cellh<=cpl*cellw)
 				break;
 		}
 	}
 
+	first = font->glyphs[0].code;
+	if(!seq)
+		first -= first%cpl;
+	last = font->glyphs[font->n_glyphs-1].code;
+
 	font->image.w = round_to_pot(cpl*cellw);
-	if(seq && font->n_glyphs<last-first+1)
-		font->image.h = (font->n_glyphs+cpl-1)/cpl*cellh;
+	if(seq)
+		font->image.h = round_to_pot((font->n_glyphs+cpl-1)/cpl*cellh);
 	else
-		font->image.h = (last-first+cpl)/cpl*cellh;
-	font->image.h = round_to_pot(font->image.h);
+		font->image.h = round_to_pot((last-first+cpl)/cpl*cellh);
 
-	font->image.data = (char *)malloc(font->image.w*font->image.h);
+	font->image.data = (char *)alloc_image_data(font->image.w, font->image.h);
+	if(!font->image.data)
+		return -1;
 	memset(font->image.data, 255, font->image.w*font->image.h);
 
 	for(i=0; i<font->n_glyphs; ++i)
 	{
-		Glyph    *glyph;
-		int      ci, cx, cy;
+		Glyph *glyph;
+		unsigned ci, cx, cy;
 		unsigned x, y;
 
 		glyph = &font->glyphs[i];
@@ -454,57 +590,86 @@ void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int s
 
 		for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 		{
-			if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h)
+			if(cx+x>=font->image.w || cy+y>=font->image.h)
 				continue;
 			font->image.data[cx+x+(cy+y)*font->image.w] = 255-glyph->image.data[x+y*glyph->image.w];
 		}
 	}
+
+	return 0;
 }
 
-void render_packed(Font *font)
+int render_packed(Font *font, unsigned margin, unsigned padding)
 {
 	unsigned i;
-	unsigned area = 0;
-	unsigned last_h = 0xFFFF;
-	char     *used_glyphs;
-	char     *used_pixels;
-	unsigned cx = 0, cy;
+	size_t area = 0;
+	char *used_glyphs;
+	unsigned *used_pixels;
+	unsigned cx = margin, cy;
+	unsigned used_h = 0;
 
+	/* Compute the total area occupied by glyphs and padding. */
 	for(i=0; i<font->n_glyphs; ++i)
-		area+=(font->glyphs[i].image.w+1)*(font->glyphs[i].image.h+1);
+	{
+		size_t a = area+(font->glyphs[i].image.w+padding)*(font->glyphs[i].image.h+padding);
+		if(a<area)
+		{
+			fprintf(stderr, "Overflow in counting total glyph area\n");
+			return -1;
+		}
+		area = a;
+	}
 
+	/* Find an image size that's no higher than wide, allowing for some
+	imperfections in the packing. */
 	for(font->image.w=1;; font->image.w<<=1)
 	{
-		font->image.h = (area*5/4)/font->image.w;
+		if(font->image.w<=margin*2)
+			continue;
+		font->image.h = (area*5/4)/(font->image.w-margin*2)+margin*2;
 		if(font->image.h<=font->image.w)
 			break;
 	}
 	font->image.h = round_to_pot(font->image.h);
 
-	font->image.data = (char *)malloc(font->image.w*font->image.h);
+	/* Allocate arrays for storing the image and keeping track of used pixels and
+	glyphs.  Since glyphs are rectangular and the image is filled starting from
+	the top, it's enough to track the number of used pixels at the top of each
+	column. */
+	font->image.data = (char *)alloc_image_data(font->image.w, font->image.h);
+	if(!font->image.data)
+		return -1;
 	memset(font->image.data, 255, font->image.w*font->image.h);
-	used_pixels = (char *)malloc(font->image.w*font->image.h);
-	memset(used_pixels, 0, font->image.w*font->image.h);
+	used_pixels = (unsigned *)malloc(font->image.w*sizeof(unsigned));
+	memset(used_pixels, 0, font->image.w*sizeof(unsigned));
 	used_glyphs = (char *)malloc(font->n_glyphs);
 	memset(used_glyphs, 0, font->n_glyphs);
 
-	for(cy=0; cy<font->image.h;)
+	for(cy=margin; cy+margin<font->image.h;)
 	{
 		unsigned w;
 		unsigned x, y;
-		Glyph    *glyph = NULL;
+		Glyph *glyph = NULL;
 		unsigned best_score = 0;
+		unsigned target_h = 0;
 
-		for(; (cx<font->image.w && used_pixels[cx+cy*font->image.w]); ++cx) ;
-		if(cx>=font->image.w)
+		/* Find the leftmost free pixel on this row.  Also record the lowest
+		extent of glyphs to the left of the free position. */
+		for(; (cx+margin<font->image.w && used_pixels[cx]>cy); ++cx)
+			if(used_pixels[cx]-cy-padding>target_h)
+				target_h = used_pixels[cx]-cy-padding;
+
+		if(cx+margin>=font->image.w)
 		{
-			cx = 0;
+			cx = margin;
 			++cy;
-			last_h = 0xFFFF;
 			continue;
 		}
-		for(w=0; (cx+w<font->image.w && !used_pixels[cx+w+cy*font->image.w]); ++w) ;
 
+		/* Count the free pixel at this position. */
+		for(w=0; (cx+w+margin<font->image.w && used_pixels[cx+w]<=cy); ++w) ;
+
+		/* Find a suitable glyph to put here. */
 		for(i=0; i<font->n_glyphs; ++i)
 		{
 			Glyph *g;
@@ -514,8 +679,11 @@ void render_packed(Font *font)
 			{
 				unsigned score;
 
-				score = g->image.h+1;
-				if(g->image.h==last_h)
+				/* Prefer glyphs that would reach exactly as low as the ones left
+				of here.  This aims to create a straight edge at the bottom for
+				lining up further glyphs. */
+				score = g->image.h+padding;
+				if(g->image.h==target_h)
 					score *= g->image.w;
 				else
 					score += g->image.w;
@@ -540,24 +708,35 @@ void render_packed(Font *font)
 
 		for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
 		{
-			if(cx+x<0 || cx+x>=font->image.w || cy+y<0 || cy+y>=font->image.h)
+			if(cx+x>=font->image.w || cy+y>=font->image.h)
 				continue;
 			font->image.data[cx+x+(cy+y)*font->image.w] = 255-glyph->image.data[x+y*glyph->image.w];
 		}
-		for(y=0; y<glyph->image.h+2; ++y) for(x=0; x<glyph->image.w+2; ++x)
+		for(x=0; x<glyph->image.w+2*padding; ++x)
 		{
-			if(cx+x<1 || cx+x>font->image.w || cy+y<1 || cy+y>font->image.h)
+			if(cx+x<padding || cx+x>=font->image.w+padding)
 				continue;
-			used_pixels[cx+x-1+(cy+y-1)*font->image.w] = 1;
+			if(used_pixels[cx+x-padding]<cy+glyph->image.h+padding)
+				used_pixels[cx+x-padding] = cy+glyph->image.h+padding;
 		}
 
-		last_h = glyph->image.h;
+		if(cy+glyph->image.h+margin>used_h)
+			used_h = cy+glyph->image.h+margin;
 	}
+
+	/* Trim the image to the actually used size, in case the original estimate
+	was too pessimistic. */
+	font->image.h = round_to_pot(used_h);
+
+	free(used_glyphs);
+	free(used_pixels);
+
+	return 0;
 }
 
 int save_defs(const char *fn, const Font *font)
 {
-	FILE     *out;
+	FILE *out;
 	unsigned i;
 
 	out = fopen(fn, "w");
@@ -567,11 +746,22 @@ int save_defs(const char *fn, const Font *font)
 		return -1;
 	}
 
-	fprintf(out, "%d %d %d %d %d\n", font->image.w, font->image.h, font->size, font->ascent, font->descent);
+	fprintf(out, "# Image/font info:\n");
+	fprintf(out, "# width height size ascent descent\n");
+	fprintf(out, "font %d %d %d %d %d\n", font->image.w, font->image.h, font->size, font->ascent, font->descent);
+	fprintf(out, "\n# Glyph info:\n");
+	fprintf(out, "# code x y width height offset_x offset_y advance\n");
 	for(i=0; i<font->n_glyphs; ++i)
 	{
 		const Glyph *g = &font->glyphs[i];
-		fprintf(out, "%u %u %u %u %u %d %d %d\n", g->code, g->x, g->y, g->image.w, g->image.h, g->offset_x, g->offset_y, g->advance);
+		fprintf(out, "glyph %u %u %u %u %u %d %d %d\n", g->code, g->x, g->y, g->image.w, g->image.h, g->offset_x, g->offset_y, g->advance);
+	}
+	fprintf(out, "\n# Kerning info:\n");
+	fprintf(out, "# left right distance\n");
+	for(i=0; i<font->n_kerning; ++i)
+	{
+		const Kerning *k = &font->kerning[i];
+		fprintf(out, "kern %u %u %d\n", k->left_code, k->right_code, k->distance);
 	}
 
 	fclose(out);
@@ -581,13 +771,13 @@ int save_defs(const char *fn, const Font *font)
 
 int save_png(const char *fn, const Image *image, char alpha)
 {
-	FILE       *out;
+	FILE *out;
 	png_struct *pngs;
-	png_info   *pngi;
-	png_byte   *rows[image->h];
-	int        i;
-	png_byte   *data2;
-	int        color;
+	png_info *pngi;
+	png_byte **rows;
+	unsigned i;
+	png_byte *data2 = 0;
+	int color;
 
 	if(!strcmp(fn, "-"))
 		out = stdout;
@@ -616,9 +806,12 @@ int save_png(const char *fn, const Image *image, char alpha)
 	}
 
 	png_init_io(pngs, out);
+	rows = (png_byte **)malloc(image->h*sizeof(png_byte *));
 	if(alpha)
 	{
-		data2 = (png_byte *)malloc(image->w*image->h*2);
+		data2 = (png_byte *)alloc_image_data(image->w*2, image->h);
+		if(!data2)
+			return -1;
 		for(i=0; i<image->w*image->h; ++i)
 		{
 			data2[i*2] = 255;
@@ -638,6 +831,7 @@ int save_png(const char *fn, const Image *image, char alpha)
 	png_set_rows(pngs, pngi, rows);
 	png_write_png(pngs, pngi, PNG_TRANSFORM_IDENTITY, NULL);
 	png_destroy_write_struct(&pngs, &pngi);
+	free(rows);
 	if(alpha)
 		free(data2);