From dde53369347a9b0a37823746166aac1f2a3eee7d Mon Sep 17 00:00:00 2001 From: Mikko Rasa Date: Fri, 23 Nov 2012 20:02:51 +0200 Subject: [PATCH] Include kerning information in definition file --- Readme | 18 +++++++++++++----- ttf2png.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 65 insertions(+), 8 deletions(-) diff --git a/Readme b/Readme index b8abf11..36728d7 100644 --- a/Readme +++ b/Readme @@ -70,17 +70,17 @@ information, called font metrics. To that end, ttf2png can write a definition file alongside the image. The basic format is line-based. Empty lines, or those starting with a hash -sign (#), should be ignored. Data lines consist of fields separated with -spaces. +sign (#), should be ignored. Data lines consist of a keyword followed by +space-separated fields. -The first data line contains five fields with overall information about the -image and the font: +The keyword "font" is followed by five fields with overall information about +the image and the font: Fields 1-2: width and height of the image Field 3: nominal size of the font Fields 4-5: ascent and descent of the font -Subsequent data lines each describe a single glyph and contain eight fields: +The keyword "glyph" is followed by eight fields describing a single glyph: Field 1: the code point of the glyph Fields 2-3: x and y position of the glyph in the image @@ -88,6 +88,13 @@ Subsequent data lines each describe a single glyph and contain eight fields: Fields 6-7: x and y offset of the glyph from its base point Field 8: advance from this glyph to the next +The keyword "kern" is followed by three fields describing kerning between two +glyphs: + + Field 1: the code point of the left-hand glyph + Field 2: the code point of the right-hand glyph + Field 3: kerning distance between the glyphs + The following ASCII art image illustrates most of these metrics. Note that in some fonts, not all of the glyphs fit completely inside the character box. @@ -120,6 +127,7 @@ next - Improve the packing algorithm - Non-square cells for grid mode - Option to invert colors +- Include kerning information in definition file 0.3 - Restructure the code diff --git a/ttf2png.c b/ttf2png.c index b8f48a8..e702c9f 100644 --- a/ttf2png.c +++ b/ttf2png.c @@ -33,6 +33,7 @@ typedef struct sImage typedef struct sGlyph { + unsigned index; unsigned code; Image image; unsigned x, y; @@ -41,6 +42,13 @@ typedef struct sGlyph int advance; } Glyph; +typedef struct sKerning +{ + unsigned left_code; + unsigned right_code; + int distance; +} Kerning; + typedef struct sFont { unsigned size; @@ -48,6 +56,8 @@ typedef struct sFont int descent; unsigned n_glyphs; Glyph *glyphs; + unsigned n_kerning; + Kerning *kerning; Image image; } Font; @@ -284,7 +294,7 @@ void usage() void 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; @@ -331,6 +341,7 @@ 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; @@ -356,6 +367,37 @@ 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; in_glyphs; ++i) for(j=0; jn_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); } void render_grid(Font *font, unsigned cellw, unsigned cellh, unsigned cpl, int seq) @@ -592,13 +634,20 @@ int save_defs(const char *fn, const Font *font) fprintf(out, "# Image/font info:\n"); fprintf(out, "# width height size ascent descent\n"); - fprintf(out, "%d %d %d %d %d\n", font->image.w, font->image.h, font->size, font->ascent, font->descent); + 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; in_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; in_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); -- 2.43.0