typedef struct sGlyph
{
+ unsigned index;
unsigned code;
Image image;
unsigned x, y;
int advance;
} Glyph;
+typedef struct sKerning
+{
+ unsigned left_code;
+ unsigned right_code;
+ int distance;
+} Kerning;
+
typedef struct sFont
{
unsigned size;
int descent;
unsigned n_glyphs;
Glyph *glyphs;
+ unsigned n_kerning;
+ Kerning *kerning;
Image image;
} Font;
-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 *);
+unsigned round_to_pot(unsigned);
+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 *);
int save_defs(const char *, const Font *);
int save_png(const char *, const Image *, char);
cellw = strtol(optarg, &ptr, 0);
if(ptr[0]=='x' && isdigit(ptr[1]))
cellh = strtol(ptr+1, NULL, 0);
+ else
+ cellh = cellw;
}
break;
case 'o':
}
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);
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);
return 0;
}
+void usage()
+{
+ 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");
+
+ printf("Usage: ttf2png [options] <TTF file>\n\n");
+
+ printf("Accepted options (default values in [brackets])\n"
+ " -r Range of characters to convert [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");
+ 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\n"
+ " -p Pack the glyphs tightly instead of in a grid\n"
+ " -d File name for writing glyph definitions\n"
+ " -h Print this message\n");
+}
+
unsigned round_to_pot(unsigned n)
{
n -= 1;
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;
}
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)
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;
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;
if(cellw==0)
{
+ /* Establish a large enough cell to hold all glyphs in the range. */
int square = (cellh==cellw);
cellw = maxw;
cellh = top-bot;
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;
- 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;
+ unsigned ci, cx, cy;
unsigned x, y;
glyph = &font->glyphs[i];
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 i;
- unsigned area = 0;
+ size_t area = 0;
char *used_glyphs;
- char *used_pixels;
+ unsigned *used_pixels;
unsigned cx = 0, 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+1)*(font->glyphs[i].image.h+1);
+ 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;
}
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);
unsigned best_score = 0;
unsigned target_h = 0;
- for(; (cx<font->image.w && used_pixels[cx+cy*font->image.w]); ++cx) ;
+ /* Find the leftmost free pixel on this row. Also record the lowest extent of glyphs
+ to the left of the free position. */
+ for(; (cx<font->image.w && used_pixels[cx]>cy); ++cx)
+ if(used_pixels[cx]-cy-1>target_h)
+ target_h = used_pixels[cx]-cy-1;
+
if(cx>=font->image.w)
{
cx = 0;
++cy;
continue;
}
- for(w=0; (cx+w<font->image.w && !used_pixels[cx+w+cy*font->image.w]); ++w) ;
- for(x=0; x<cx; ++x)
- {
- for(y=0; (cy+y+1<font->image.h && used_pixels[cx-x+(cy+y+1)*font->image.w]); ++y) ;
- if(y>target_h)
- target_h = y;
- }
+ /* Count the free pixel at this position. */
+ for(w=0; (cx+w<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;
{
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+1;
if(g->image.h==target_h)
score *= g->image.w;
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; ++x)
{
- if(cx+x<1 || cx+x>font->image.w || cy+y<1 || cy+y>font->image.h)
+ if(cx+x<1 || cx+x>font->image.w)
continue;
- used_pixels[cx+x-1+(cy+y-1)*font->image.w] = 1;
+ if(used_pixels[cx+x-1]<cy+glyph->image.h+1)
+ used_pixels[cx+x-1] = cy+glyph->image.h+1;
}
if(cy+glyph->image.h>used_h)
used_h = cy+glyph->image.h;
}
+ /* 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)
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);
FILE *out;
png_struct *pngs;
png_info *pngi;
- png_byte *rows[image->h];
- int i;
- png_byte *data2;
+ png_byte **rows;
+ unsigned i;
+ png_byte *data2 = 0;
int color;
if(!strcmp(fn, "-"))
}
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;
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);