X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=ttf2png.c;h=76c2e0d96d7330fa530fe00d842b42eca40573e7;hb=HEAD;hp=dfdde4b789c6428c14223c43bec4287a5a5646ea;hpb=0cf5a030243dc072cd53af71988e10e03e6462ae;p=ttf2png.git

diff --git a/ttf2png.c b/ttf2png.c
index dfdde4b..76c2e0d 100644
--- a/ttf2png.c
+++ b/ttf2png.c
@@ -1,6 +1,6 @@
 /*
 ttf2png - True Type Font to PNG converter
-Copyright (c) 2004 Mikkosoft Productions
+Copyright (c) 2004-2021 Mikko Rasa, Mikkosoft Productions
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -18,39 +18,110 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
 
 #include <stdio.h>
+#include <ctype.h>
 #include <unistd.h>
 #include <getopt.h>
 #include <png.h>
 #include <ft2build.h>
 #include FT_FREETYPE_H
 
-void usage();
-int save_png(char *, char *, int, int);
+typedef struct sImage
+{
+	unsigned w, h;
+	unsigned char *data;
+	unsigned border;
+} Image;
+
+typedef struct sGlyph
+{
+	unsigned index;
+	unsigned code;
+	Image image;
+	unsigned x, y;
+	int offset_x;
+	int offset_y;
+	int advance;
+} Glyph;
+
+typedef struct sKerning
+{
+	Glyph *left_glyph;
+	Glyph *right_glyph;
+	int distance;
+} Kerning;
+
+typedef struct sFont
+{
+	unsigned size;
+	int ascent;
+	int descent;
+	unsigned n_glyphs;
+	Glyph *glyphs;
+	unsigned n_kerning;
+	Kerning *kerning;
+	Image image;
+} Font;
+
+typedef struct sRange
+{
+	unsigned first;
+	unsigned last;
+} Range;
 
-char	verbose=0;
-char	alpha=0;
+typedef unsigned char bool;
+
+void usage(void);
+int convert_numeric_option(char, int);
+void convert_code_point_range(char, Range *);
+int str_to_code_point(const char *, char **);
+void convert_size(char, unsigned *, unsigned *);
+void sort_and_compact_ranges(Range *, unsigned *);
+int range_cmp(const void *, const void *);
+unsigned round_to_pot(unsigned);
+int init_image(Image *, size_t, size_t);
+int init_font(Font *, FT_Face, const Range *, unsigned, bool, unsigned, unsigned);
+int init_glyphs(Font *, FT_Face, const Range *, bool, unsigned, unsigned);
+int copy_bitmap(const FT_Bitmap *, Image *);
+unsigned sqrti(unsigned);
+unsigned find_distance_to_edge(const Image *, int, int, unsigned);
+int create_distance_field(const FT_Bitmap *, Image *, unsigned, unsigned);
+int render_grid(Font *, unsigned, unsigned, unsigned, bool);
+int render_packed(Font *, unsigned, unsigned);
+int save_defs(const char *, const Font *);
+int save_png(const char *, const Image *, bool, bool, bool);
+
+char verbose = 0;
 
 int main(int argc, char **argv)
 {
-	FT_Library	freetype;
-	FT_Face		face;
-	int	err;
-	int	o;
-	int	begin=0;
-	int	end=255;
-	char	*fn;
-	int	size=10;
-	int	cpl=16;
-	int	w,h;
-	int	i;
-	char	*data;
-	int	ch,cw;
-	int	cell=16;
-	int	ascent;
-	char	*out="font.png";
-	const char	*name;
-	char	autohinter=0;
-	int	count;
+	char *fn;
+	Range *ranges = NULL;
+	unsigned n_ranges = 0;
+	unsigned size = 10;
+	unsigned cpl = 0;
+	unsigned cellw = 0;
+	unsigned cellh = 0;
+	bool autohinter = 0;
+	bool seq = 0;
+	bool alpha = 0;
+	bool invert = 0;
+	bool pack = 0;
+	unsigned margin = 0;
+	unsigned padding = 1;
+	bool npot = 0;
+	unsigned distfield = 0;
+	unsigned border = 0;
+
+	FT_Library freetype;
+	FT_Face face;
+
+	int err;
+	int i;
+
+	char *out_fn = "font.png";
+	char *def_fn = NULL;
+
+	Font font;
 
 	if(argc<2)
 	{
@@ -58,44 +129,31 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	while((o=getopt(argc,argv,"r:s:l:c:o:atvh?"))!=-1)
+	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:pim:n:gf:b:")) != -1)
 	{
-		char	*ptr;
-		int	temp;
-		switch(o)
+		switch(i)
 		{
 		case 'r':
-			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);
-			else
-			{
-				begin=temp;
-				end=strtol(ptr+1,NULL,0);
-			}
+			ranges = (Range *)realloc(ranges, (++n_ranges)*sizeof(Range));
+			convert_code_point_range('r', &ranges[n_ranges-1]);
 			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':
-			cell=strtol(optarg,NULL,0);
+			convert_size('c', &cellw, &cellh);
 			break;
 		case 'o':
-			out=optarg;
+			out_fn = optarg;
 			break;
 		case 'a':
-			autohinter=1;
+			autohinter = 1;
 			break;
 		case 't':
-			alpha=1;
+			alpha = 1;
 			break;
 		case 'v':
 			++verbose;
@@ -104,183 +162,995 @@ int main(int argc, char **argv)
 		case '?':
 			usage();
 			return 0;
+		case 'e':
+			seq = 1;
+			break;
+		case 'd':
+			def_fn = optarg;
+			break;
+		case 'p':
+			pack = 1;
+			break;
+		case 'i':
+			invert = 1;
+			break;
+		case 'm':
+			margin = convert_numeric_option('m', 0);
+			break;
+		case 'n':
+			padding = convert_numeric_option('n', 0);
+			break;
+		case 'g':
+			npot = 1;
+			break;
+		case 'f':
+			distfield = convert_numeric_option('f', 1);
+			break;
+		case 'b':
+			border = convert_numeric_option('b', 1);
+			break;
 		}
 	}
+	if(!strcmp(out_fn, "-"))
+		verbose = 0;
 
-	if(optind>=argc)
+	if(optind!=argc-1)
 	{
 		usage();
 		return 1;
 	}
-	fn=argv[optind];
 
-	err=FT_Init_FreeType(&freetype);
+	fn = argv[optind];
+
+	err = FT_Init_FreeType(&freetype);
 	if(err)
 	{
-		fprintf(stderr,"Couldn't initialize FreeType library\n");
+		fprintf(stderr, "Couldn't initialize FreeType library\n");
 		return 1;
 	}
 
-	err=FT_New_Face(freetype,fn,0,&face);
+	err = FT_New_Face(freetype, fn, 0, &face);
 	if(err)
 	{
-		fprintf(stderr,"Couldn't load font file\n");
+		fprintf(stderr, "Couldn't load font file\n");
 		if(err==FT_Err_Unknown_File_Format)
-			fprintf(stderr,"Unknown file format\n");
+			fprintf(stderr, "Unknown file format\n");
 		return 1;
 	}
 
-	name=FT_Get_Postscript_Name(face);
 	if(verbose)
 	{
-		printf("Font name: %s\n",name);
-		printf("Glyphs: %ld\n",face->num_glyphs);
+		const char *name = FT_Get_Postscript_Name(face);
+		printf("Font name: %s\n", name);
+		printf("Glyphs:    %ld\n", face->num_glyphs);
+	}
+
+	font.size = size;
+	if(distfield)
+	{
+		if(!border)
+			border = sqrti(font.size);
+		size *= distfield;
 	}
 
-	err=FT_Set_Pixel_Sizes(face,0,size);
+	err = FT_Set_Pixel_Sizes(face, 0, size);
 	if(err)
 	{
-		fprintf(stderr,"Couldn't set size\n");
+		fprintf(stderr, "Couldn't set size\n");
 		return 1;
 	}
-	ascent=(face->bbox.yMax*face->size->metrics.x_scale)>>16;
-	ascent=(ascent+63)/64;
-	ch=((face->bbox.yMax-face->bbox.yMin)*face->size->metrics.y_scale)>>16;
-	ch=(ch+63)/64;
-	cw=((face->bbox.xMax-face->bbox.xMin)*face->size->metrics.x_scale)>>16;
-	cw=(cw+63)/64;
-	if(verbose)
+
+	if(!n_ranges)
 	{
-		printf("Ascent %d\n",ascent);
-		printf("Descent %ld\n",(((face->bbox.yMin*face->size->metrics.y_scale)>>16)+63)/64);
-		printf("Max height %d\n",ch);
-		printf("Max width %d\n",cw);
-	}
-	if(verbose>=1 && (ch>cell || cw>cell)) fprintf(stderr,"Warning: character size exceeds cell size\n");
-
-	w=cpl*cell;
-	h=(end-begin+cpl-1)/cpl*cell;
-	data=(char *)malloc(w*h);
-	memset(data,255,w*h);
-
-	count=0;
-	for(i=begin;i<=end;++i)
-	{
-		int			glyph=FT_Get_Char_Index(face,i);
-		FT_Bitmap	*bmp=&face->glyph->bitmap;
-		int			x,y;
-		int			cx=(i%cpl)*cell;
-		int			cy=(i/cpl)*cell;
-		int			flags=0;
-		int			dy;
-		if(!glyph) continue;
-		fflush(stdout);
-		if(autohinter) flags|=FT_LOAD_FORCE_AUTOHINT;
-		FT_Load_Glyph(face,glyph,flags);
-		FT_Render_Glyph(face->glyph,FT_RENDER_MODE_NORMAL);
-		if(cell>bmp->width) cx+=(cell-bmp->width)/2;
-		dy=ascent-face->glyph->bitmap_top;
-		cy+=dy;
+		ranges = malloc(sizeof(Range));
+		ranges[0].first = 0;
+		ranges[0].last = 255;
+		n_ranges = 1;
+	}
+	else
+		sort_and_compact_ranges(ranges, &n_ranges);
+
+	err = init_font(&font, face, ranges, n_ranges, autohinter, distfield, border);
+	if(err)
+		return 1;
+
+	if(!font.n_glyphs)
+	{
+		fprintf(stderr, "No glyphs found in the requested range\n");
+		return 1;
+	}
+
+	if(pack)
+		err = render_packed(&font, margin, padding);
+	else
+		err = render_grid(&font, cellw, cellh, cpl, seq);
+	if(err)
+		return 1;
+
+	err = save_png(out_fn, &font.image, (alpha && !distfield), (invert || distfield), npot);
+	if(err)
+		return 1;
+
+	if(def_fn)
+		save_defs(def_fn, &font);
+
+	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);
+	free(ranges);
+
+	FT_Done_Face(face);
+	FT_Done_FreeType(freetype);
+
+	return 0;
+}
+
+void usage(void)
+{
+	printf("ttf2png 2.0 - True Type Font to PNG converter\n"
+		"Copyright (c) 2004-2021  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"
+		"  -g  Allow non-power-of-two result\n");
+	printf("  -f  Create a distance field texture\n"
+		"  -b  Specify distance field border zone width\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, Range *range)
+{
+	int value;
+	char *ptr;
+
+	if(!strcmp(optarg, "all"))
+	{
+		range->first = 0;
+		range->last = 0x10FFFF;
+		return;
+	}
+
+	value = str_to_code_point(optarg, &ptr);
+	if(value>=0 && *ptr==',')
+	{
+		range->first = value;
+		value = str_to_code_point(ptr+1, &ptr);
+		if(value>=(int)range->first && !*ptr)
+		{
+			range->last = value;
+			return;
+		}
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
+int str_to_code_point(const char *nptr, char **endptr)
+{
+	if(nptr[0]=='U' && nptr[1]=='+')
+		return strtoul(nptr+2, endptr, 16);
+	else if(nptr[0]&0x80)
+	{
+		unsigned bytes;
+		unsigned code;
+		unsigned i;
+
+		if(endptr)
+			*endptr = (char *)nptr;
+
+		for(bytes=1; (bytes<4 && (nptr[0]&(0x80>>bytes))); ++bytes)
+			if((nptr[bytes]&0xC0)!=0x80)
+				return -1;
+		if(bytes<2)
+			return -1;
+
+		code = nptr[0]&(0x3F>>bytes);
+		for(i=1; i<bytes; ++i)
+			code = (code<<6)|(nptr[i]&0x3F);
+
+		if(endptr)
+			*endptr = (char *)nptr+bytes;
+
+		return code;
+	}
+	else if(isdigit(nptr[0]))
+		return strtoul(nptr, endptr, 0);
+	else
+	{
+		if(endptr)
+			*endptr = (char *)nptr+1;
+		return *nptr;
+	}
+}
+
+void convert_size(char opt, unsigned *width, unsigned *height)
+{
+	int value;
+	char *ptr;
+
+	if(!strcmp(optarg, "auto"))
+	{
+		*width = 0;
+		*height = 0;
+		return;
+	}
+	else if(!strcmp(optarg, "autorect"))
+	{
+		*width = 0;
+		*height = 1;
+		return;
+	}
+
+	value = strtol(optarg, &ptr, 0);
+	if(value>0)
+	{
+		*width = value;
+		if(*ptr=='x')
+		{
+			value = strtol(ptr+1, &ptr, 0);
+			if(value>0 && !*ptr)
+			{
+				*height = value;
+				return;
+			}
+		}
+		else if(!*ptr)
+		{
+			*height = *width;
+			return;
+		}
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
+void sort_and_compact_ranges(Range *ranges, unsigned *n_ranges)
+{
+	unsigned i, j;
+
+	if(!*n_ranges)
+		return;
+
+	qsort(ranges, *n_ranges, sizeof(Range), &range_cmp);
+	for(i=0, j=1; j<*n_ranges; ++j)
+	{
+		if(ranges[i].last+1>=ranges[j].first)
+		{
+			if(ranges[j].last>ranges[i].last)
+				ranges[i].last = ranges[j].last;
+		}
+		else
+		{
+			++i;
+			if(i!=j)
+				ranges[i] = ranges[j];
+		}
+	}
+
+	*n_ranges = i+1;
+}
+
+int range_cmp(const void *p1, const void *p2)
+{
+	const Range *r1 = (const Range *)p1;
+	const Range *r2 = (const Range *)p2;
+	if(r1->first!=r2->first)
+		return (r1->first<r2->first ? -1 : 1);
+	else if(r1->last!=r2->last)
+		return (r1->last<r2->last ? -1 : 1);
+	else
+		return 0;
+}
+
+unsigned round_to_pot(unsigned n)
+{
+	n -= 1;
+	n |= n>>1;
+	n |= n>>2;
+	n |= n>>4;
+	n |= n>>8;
+	n |= n>>16;
+
+	return n+1;
+}
+
+int init_image(Image *image, size_t w, size_t h)
+{
+	size_t s;
+
+	image->w = w;
+	image->h = h;
+	image->data = NULL;
+	image->border = 0;
+
+	if(!image->w || !image->h)
+		return 0;
+
+	s = w*h;
+	if(s/h!=w)
+	{
+		fprintf(stderr, "Cannot allocate memory for a %dx%d image\n", image->w, image->h);
+		return -1;
+	}
+
+	image->data = malloc(s);
+	if(!image->data)
+	{
+		fprintf(stderr, "Cannot allocate memory for a %dx%d image\n", image->w, image->h);
+		return -1;
+	}
+
+	return 0;
+}
+
+int init_font(Font *font, FT_Face face, const Range *ranges, unsigned n_ranges, bool autohinter, unsigned distfield, unsigned border)
+{
+	unsigned i, j;
+	unsigned size = 0;
+	int scale = (distfield>0 ? distfield : 1);
+
+	font->ascent = (face->size->metrics.ascender/scale+63)/64;
+	font->descent = (face->size->metrics.descender/scale-63)/64;
+
+	if(verbose>=1)
+	{
+		printf("Ascent:    %d\n", font->ascent);
+		printf("Descent:   %d\n", font->descent);
+	}
+
+	font->n_glyphs = 0;
+	font->glyphs = NULL;
+	for(i=0; i<n_ranges; ++i)
+		if(init_glyphs(font, face, &ranges[i], autohinter, distfield, border))
+			return -1;
+
+	if(verbose>=1)
+		printf("Loaded %u glyphs\n", font->n_glyphs);
+
+	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_glyph = &font->glyphs[i];
+				kern->right_glyph = &font->glyphs[j];
+				kern->distance = (kerning.x/scale+32)/64;
+			}
+		}
+
+	if(verbose>=1)
+		printf("Loaded %d kerning pairs\n", font->n_kerning);
+
+	return 0;
+}
+
+int init_glyphs(Font *font, FT_Face face, const Range *range, bool autohinter, unsigned distfield, unsigned border)
+{
+	unsigned i, j;
+	unsigned size = font->n_glyphs;
+	int scale = (distfield>0 ? distfield : 1);
+
+	for(i=range->first; i<=range->last; ++i)
+	{
+		unsigned n;
+		FT_Bitmap *bmp = &face->glyph->bitmap;
+		int flags = 0;
+		Glyph *glyph;
+
+		n = FT_Get_Char_Index(face, i);
+		if(!n)
+			continue;
+
+		if(autohinter)
+			flags |= FT_LOAD_FORCE_AUTOHINT;
+		FT_Load_Glyph(face, n, flags);
+		FT_Render_Glyph(face->glyph, (distfield ? FT_RENDER_MODE_MONO : FT_RENDER_MODE_NORMAL));
+
 		if(verbose>=2)
 		{
-			printf("  Char %d: glyph %d, size %dx%d\n",i,glyph,bmp->width,bmp->rows);
-			if(bmp->width>cell || dy+bmp->rows>cell || dy<0) printf("  Warning: Character %d does not fit in cell\n",i);
+			printf("  Code point U+%04X", i);
+			if(i>=0x20 && i<0x7F)
+				printf(" (%c)", i);
+			else if(i>=0xA0 && i<=0x10FFFF)
+			{
+				char utf8[5];
+				unsigned bytes;
+
+				for(bytes=2; i>>(1+bytes*5); ++bytes) ;
+				for(j=0; j<bytes; ++j)
+					utf8[j] = 0x80 | ((i>>((bytes-j-1)*6))&0x3F);
+				utf8[0] |= 0xF0<<(4-bytes);
+				utf8[j] = 0;
+
+				printf(" (%s)", utf8);
+			}
+			printf(": glyph %u, size %dx%d\n", n, bmp->width/scale, bmp->rows/scale);
 		}
-		if(bmp->pitch<0)
+
+		if(bmp->pixel_mode!=FT_PIXEL_MODE_GRAY && bmp->pixel_mode!=FT_PIXEL_MODE_MONO)
 		{
-			fprintf(stderr,"Warning: Character %d not rendered (can't handle reversed bitmaps)\n",i);
+			fprintf(stderr, "Warning: Glyph %u skipped, incompatible pixel mode\n", n);
 			continue;
 		}
-		for(y=0;y<bmp->rows;++y) for(x=0;x<bmp->width;++x)
+
+		if(font->n_glyphs>=size)
+		{
+			size += 16;
+			font->glyphs = (Glyph *)realloc(font->glyphs, size*sizeof(Glyph));
+		}
+
+		glyph = &font->glyphs[font->n_glyphs++];
+		glyph->index = n;
+		glyph->code = i;
+		glyph->offset_x = (int)(face->glyph->bitmap_left+scale/2)/scale;
+		glyph->offset_y = (int)(face->glyph->bitmap_top-bmp->rows+scale/2)/scale;
+		glyph->advance = (int)(face->glyph->advance.x/scale+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(distfield)
+		{
+			glyph->offset_x -= border;
+			glyph->offset_y -= border;
+			create_distance_field(bmp, &glyph->image, distfield, border);
+		}
+		else
 		{
-			if(cx+x<0 || cx+x>=w || cy+y<0 || cy+y>=h) continue;
-			data[cx+x+(cy+y)*w]=255-bmp->buffer[x+y*bmp->pitch];
+			if(copy_bitmap(bmp, &glyph->image))
+				return -1;
 		}
-		++count;
 	}
 
-	save_png(out,data,w,h);
+	return 0;
+}
 
-	if(verbose) printf("Converted %d glyphs\n",count);
+int copy_bitmap(const FT_Bitmap *bmp, Image *image)
+{
+	unsigned x, y;
+	unsigned char *src;
+	unsigned char *dst;
+
+	if(init_image(image, bmp->width, bmp->rows))
+		return -1;
+	if(!image->w || !image->h)
+		return 0;
+
+	if(bmp->pitch<0)
+		src = bmp->buffer+(bmp->rows-1)*-bmp->pitch;
+	else
+		src = bmp->buffer;
+	dst = image->data;
+
+	for(y=0; y<bmp->rows; ++y)
+	{
+		if(bmp->pixel_mode==FT_PIXEL_MODE_MONO)
+		{
+			for(x=0; x<bmp->width; ++x)
+				dst[x] = ((src[x/8]&(0x80>>(x%8))) ? 0xFF : 0x00);
+		}
+		else
+		{
+			for(x=0; x<bmp->width; ++x)
+				dst[x] = src[x];
+		}
+
+		src += bmp->pitch;
+		dst += image->w;
+	}
 
 	return 0;
 }
 
-void usage()
+unsigned sqrti(unsigned num)
 {
-	printf("ttf2png - True Type Font to PNG converter\n"
-		"Copyright (c) 2004 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 [16]\n"
-		"  -c  Character cell size, in pixels [16]\n"
-		"  -o  Output file name [font.png]\n"
-		"  -a  Force autohinter\n"
-		"  -t  Render font to alpha channel\n"
-		"  -v  Increase the level of verbosity\n"
-		"  -h  Print this message\n");
+	unsigned result = (num>0xFFFF ? 0xFFFF : 0x100);
+	while(result && result*result>=result+num)
+		result -= (result*result+result-num)/(result*2);
+
+	return result;
+}
+
+unsigned find_distance_to_edge(const Image *image, int origin_x, int origin_y, unsigned range)
+{
+	unsigned i, j;
+	int x, y;
+	unsigned char origin_pixel = 0;
+	unsigned closest = range*range;
+
+	if(origin_x>=0 && (unsigned)origin_x<image->w && origin_y>=0 && (unsigned)origin_y<image->h)
+		origin_pixel = image->data[origin_x+origin_y*image->w];
+
+	x = origin_x-1;
+	y = origin_y-1;
+	for(i=1; (i<range && i*i<=closest); ++i, --x, --y) for(j=0; j<4; ++j)
+	{
+		unsigned k;
+		int dx = (j==0 ? 1 : j==2 ? -1 : 0);
+		int dy = (j==1 ? 1 : j==3 ? -1 : 0);
+
+		for(k=0; k<i*2; ++k, x+=dx, y+=dy)
+		{
+			unsigned char pixel = 0;
+			if(x>=0 && (unsigned)x<image->w && y>=0 && (unsigned)y<image->h)
+				pixel = image->data[x+y*image->w];
+				
+			if((pixel^origin_pixel)&0x80)
+			{
+				unsigned d = 2*i*i + k*k - 2*k*i;
+				if(d<closest)
+					closest = d;
+			}
+		}
+	}
+
+	return sqrti(closest*0x3F01)/range;
+}
+
+int create_distance_field(const FT_Bitmap *bmp, Image *image, unsigned scale, unsigned margin)
+{
+	unsigned x, y;
+	Image base_image;
+
+	if(init_image(image, (bmp->width+scale-1)/scale+2*margin, (bmp->rows+scale-1)/scale+2*margin))
+		return -1;
+	if(!image->w || !image->h)
+		return 0;
+
+	if(copy_bitmap(bmp, &base_image))
+		return -1;
+
+	image->border = margin;
+	for(y=0; y<image->h; ++y) for(x=0; x<image->w; ++x)
+	{
+		int bx = (x-margin)*scale+scale/2;
+		int by = (y-margin)*scale+scale/2;
+		unsigned char pixel = find_distance_to_edge(&base_image, bx, by, margin*scale);
+		if(bx>=0 && (unsigned)bx<base_image.w && by>=0 && (unsigned)by<base_image.h)
+			pixel |= base_image.data[bx+by*base_image.w]&0x80;
+		if(!(pixel&0x80))
+			pixel = 0x80-pixel;
+		image->data[x+y*image->w] = pixel;
+	}
+
+	free(base_image.data);
+
+	return 0;
+}
+
+int render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, bool seq)
+{
+	unsigned i;
+	int top = 0, bot = 0;
+	unsigned first, n_cells;
+	unsigned maxw = 0, maxh = 0;
+
+	/* Find extremes of the glyph images. */
+	for(i=0; i<font->n_glyphs; ++i)
+	{
+		int y;
+
+		y = font->glyphs[i].offset_y+font->glyphs[i].image.h;
+		if(y>top)
+			top = y;
+		if(font->glyphs[i].offset_y<bot)
+			bot = font->glyphs[i].offset_y;
+		if(font->glyphs[i].image.w>maxw)
+			maxw = font->glyphs[i].image.w;
+		if(font->glyphs[i].image.h>maxh)
+			maxh = font->glyphs[i].image.h;
+	}
+
+	if(cellw==0)
+	{
+		/* Establish a large enough cell to hold all glyphs in the range. */
+		int square = (cellh==cellw);
+		cellw = maxw;
+		cellh = top-bot;
+		if(square)
+		{
+			if(cellh>cellw)
+				cellw = cellh;
+			else
+				cellh = cellw;
+		}
+	}
+
+	if(verbose>=1)
+	{
+		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 || (unsigned)(top-bot)>cellh)
+			fprintf(stderr, "Warning: character size exceeds cell size\n");
+	}
+
+	if(cpl==0)
+	{
+		/* 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 && font->n_glyphs/cpl*cellh<=cpl*cellw)
+				break;
+		}
+	}
+
+	first = font->glyphs[0].code;
+	if(seq)
+		n_cells = font->n_glyphs;
+	else
+	{
+		first -= first%cpl;
+		n_cells = font->glyphs[font->n_glyphs-1].code+1-first;
+	}
+
+	if(init_image(&font->image, cpl*cellw, (n_cells+cpl-1)/cpl*cellh))
+		return -1;
+	memset(font->image.data, 0, font->image.w*font->image.h);
+
+	for(i=0; i<font->n_glyphs; ++i)
+	{
+		Glyph *glyph;
+		unsigned ci, cx, cy;
+		unsigned x, y;
+
+		glyph = &font->glyphs[i];
+
+		if(seq)
+			ci = i;
+		else
+			ci = glyph->code-first;
+
+		cx = (ci%cpl)*cellw;
+		cy = (ci/cpl)*cellh;
+
+		if(cellw>glyph->image.w)
+			cx += (cellw-glyph->image.w)/2;
+		cy += top-glyph->offset_y-glyph->image.h;
+
+		glyph->x = cx;
+		glyph->y = cy;
+
+		for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
+		{
+			if(cx+x>=font->image.w || cy+y>=font->image.h)
+				continue;
+			font->image.data[cx+x+(cy+y)*font->image.w] = glyph->image.data[x+y*glyph->image.w];
+		}
+	}
+
+	return 0;
+}
+
+int render_packed(Font *font, unsigned margin, unsigned padding)
+{
+	unsigned i;
+	size_t area = 0;
+	bool *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)
+	{
+		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 approximately square. */
+	for(font->image.w=1;; font->image.w<<=1)
+	{
+		if(font->image.w<=margin*2)
+			continue;
+		font->image.h = area/(font->image.w-margin*2)+margin*2;
+		if(font->image.h<=font->image.w)
+			break;
+	}
+
+	/* Add some extra space to accommodate packing imperfections. */
+	font->image.h = font->image.h*3/2;
+
+	/* 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. */
+	if(init_image(&font->image, font->image.w, font->image.h))
+		return -1;
+	memset(font->image.data, 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 = (bool *)malloc(font->n_glyphs);
+	memset(used_glyphs, 0, font->n_glyphs);
+
+	for(cy=margin; cy+margin<font->image.h;)
+	{
+		unsigned w;
+		unsigned x, y;
+		Glyph *glyph = NULL;
+		unsigned best_score = 0;
+		unsigned target_h = 0;
+
+		/* 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 = margin;
+			++cy;
+			continue;
+		}
+
+		/* 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;
+
+			g = &font->glyphs[i];
+			if(!used_glyphs[i] && g->image.w<=w)
+			{
+				unsigned score;
+
+				/* 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;
+
+				if(score>best_score)
+				{
+					glyph = g;
+					best_score = score;
+				}
+			}
+		}
+
+		if(!glyph)
+		{
+			cx += w;
+			continue;
+		}
+
+		used_glyphs[glyph-font->glyphs] = 1;
+		glyph->x = cx;
+		glyph->y = cy;
+
+		for(y=0; y<glyph->image.h; ++y) for(x=0; x<glyph->image.w; ++x)
+		{
+			if(cx+x>=font->image.w || cy+y>=font->image.h)
+				continue;
+			font->image.data[cx+x+(cy+y)*font->image.w] = glyph->image.data[x+y*glyph->image.w];
+		}
+		for(x=0; x<glyph->image.w+2*padding; ++x)
+		{
+			if(cx+x<padding || cx+x>=font->image.w+padding)
+				continue;
+			if(used_pixels[cx+x-padding]<cy+glyph->image.h+padding)
+				used_pixels[cx+x-padding] = cy+glyph->image.h+padding;
+		}
+
+		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 = used_h;
+
+	free(used_glyphs);
+	free(used_pixels);
+
+	return 0;
 }
 
-int save_png(char *fn, char *data, int w, int h)
+int save_defs(const char *fn, const Font *font)
 {
-	FILE			*out;
-	png_struct	*pngs;
-	png_info		*pngi;
-	png_byte		*rows[h];
-	int			i;
-	png_byte		*data2;
-	int			color;
-
-	out=fopen(fn,"wb");
+	FILE *out;
+	unsigned i;
+
+	out = fopen(fn, "w");
 	if(!out)
 	{
-		fprintf(stderr,"Couldn't open output file\n");
+		fprintf(stderr, "Couldn't open %s\n",fn);
 		return -1;
 	}
 
-	pngs=png_create_write_struct(PNG_LIBPNG_VER_STRING,NULL,NULL,NULL);
+	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# Code point mapping:\n");
+	fprintf(out, "# code index\n");
+	for(i=0; i<font->n_glyphs; ++i)
+	{
+		const Glyph *g = &font->glyphs[i];
+		fprintf(out, "code %u %u\n", g->code, g->index);
+	}
+
+	fprintf(out, "\n# Metrics info:\n");
+	fprintf(out, "# index width height offset_x offset_y advance\n");
+	for(i=0; i<font->n_glyphs; ++i)
+	{
+		const Glyph *g = &font->glyphs[i];
+		int b = g->image.border;
+		fprintf(out, "metrics %u %u %u %d %d %d\n", g->index, g->image.w-2*b, g->image.h-2*b, g->offset_x+b, g->offset_y+b, g->advance);
+	}
+
+	fprintf(out, "\n# Glyph info:\n");
+	fprintf(out, "# index x y width height border\n");
+	for(i=0; i<font->n_glyphs; ++i)
+	{
+		const Glyph *g = &font->glyphs[i];
+		fprintf(out, "glyph %u %u %u %u %u %u\n", g->index, g->x, g->y, g->image.w, g->image.h, g->image.border);
+	}
+
+	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_glyph->index, k->right_glyph->index, k->distance);
+	}
+
+	fclose(out);
+
+	return 0;
+}
+
+int save_png(const char *fn, const Image *image, bool alpha, bool invert, bool npot)
+{
+	FILE *out;
+	png_struct *pngs;
+	png_info *pngi;
+	unsigned w, h;
+	png_byte *row;
+	unsigned x, y;
+	int color;
+	unsigned flip_bits = (invert==alpha ? 0xFF : 0x00);
+	unsigned char *src = image->data;
+
+	if(!strcmp(fn, "-"))
+		out = stdout;
+	else
+	{
+		out = fopen(fn, "wb");
+		if(!out)
+		{
+			fprintf(stderr, "Couldn't open %s\n",fn);
+			return -1;
+		}
+	}
+
+	pngs = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
 	if(!pngs)
 	{
-		fprintf(stderr,"Error writing PNG file\n");
+		fprintf(stderr, "Error writing PNG file\n");
 		return -1;
 	}
-	pngi=png_create_info_struct(pngs);
+	pngi = png_create_info_struct(pngs);
 	if(!pngi)
 	{
-		png_destroy_write_struct(&pngs,NULL);
-		fprintf(stderr,"Error writing PNG file\n");
+		png_destroy_write_struct(&pngs, NULL);
+		fprintf(stderr, "Error writing PNG file\n");
 		return -1;
 	}
 
-	png_init_io(pngs,out);
+	w = (npot ? image->w : round_to_pot(image->w));
+	h = (npot ? image->h : round_to_pot(image->h));
+	color = (alpha ? PNG_COLOR_TYPE_GRAY_ALPHA : PNG_COLOR_TYPE_GRAY);
+	png_set_IHDR(pngs, pngi, w, h, 8, color, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+	png_init_io(pngs, out);
+	png_write_info(pngs, pngi);
+	row = (png_byte *)malloc(w*(1+alpha));
 	if(alpha)
 	{
-		data2=(png_byte *)malloc(w*h*2);
-		for(i=0;i<w*h;++i)
+		for(x=0; x<w; ++x)
+		{
+			row[x*2] = 255;
+			row[x*2+1] = flip_bits;
+		}
+		for(y=0; y<image->h; ++y)
 		{
-			data2[i*2]=255;
-			data2[i*2+1]=255-data[i];
+			for(x=0; x<image->w; ++x)
+				row[x*2+1] = *src++^flip_bits;
+			png_write_row(pngs, row);
 		}
-		for(i=0;i<h;++i)
-			rows[i]=(png_byte *)(data2+i*w*2);
-		color=PNG_COLOR_TYPE_GRAY_ALPHA;
+
+		for(x=0; x<w; ++x)
+			row[x*2+1] = 0;
 	}
 	else
 	{
-		for(i=0;i<h;++i)
-			rows[i]=(png_byte *)(data+i*w);
-		color=PNG_COLOR_TYPE_GRAY;
+		memset(row+image->w, flip_bits, w-image->w);
+		for(y=0; y<image->h; ++y)
+		{
+			for(x=0; x<image->w; ++x)
+				row[x] = *src++^flip_bits;
+			png_write_row(pngs, row);
+		}
+
+		memset(row, flip_bits, w);
 	}
-	png_set_IHDR(pngs,pngi,w,h,8,color,PNG_INTERLACE_NONE,PNG_COMPRESSION_TYPE_DEFAULT,PNG_FILTER_TYPE_DEFAULT);
-	png_set_rows(pngs,pngi,rows);
-	png_write_png(pngs,pngi,PNG_TRANSFORM_IDENTITY,NULL);
-	png_destroy_write_struct(&pngs,&pngi);
-	if(alpha) free(data2);
 
-	if(verbose) printf("Saved %dx%d PNG image to %s\n",w,h,fn);
+	for(; y<h; ++y)
+		png_write_row(pngs, row);
+
+	png_write_end(pngs, pngi);
+	png_destroy_write_struct(&pngs, &pngi);
+	free(row);
+
+	if(verbose)
+		printf("Saved %dx%d PNG image to %s\n", w, h, fn);
+
+	fclose(out);
 
 	return 0;
 }