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Diffstat (limited to 'libs/cairo-1.16.0/src/cairo-font-face-twin.c')
| -rw-r--r-- | libs/cairo-1.16.0/src/cairo-font-face-twin.c | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/libs/cairo-1.16.0/src/cairo-font-face-twin.c b/libs/cairo-1.16.0/src/cairo-font-face-twin.c new file mode 100644 index 0000000..a0855c9 --- /dev/null +++ b/libs/cairo-1.16.0/src/cairo-font-face-twin.c @@ -0,0 +1,752 @@ +/* + * Copyright © 2004 Keith Packard + * Copyright © 2008 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + * + * The Original Code is the cairo graphics library. + * + * The Initial Developer of the Original Code is Keith Packard + * + * Contributor(s): + * Keith Packard <keithp@keithp.com> + * Behdad Esfahbod <behdad@behdad.org> + */ + +#include "cairoint.h" +#include "cairo-error-private.h" + +#include <math.h> + +/* + * This file implements a user-font rendering the descendant of the Hershey + * font coded by Keith Packard for use in the Twin window system. + * The actual font data is in cairo-font-face-twin-data.c + * + * Ported to cairo user font and extended by Behdad Esfahbod. + */ + + + +static cairo_user_data_key_t twin_properties_key; + + +/* + * Face properties + */ + +/* We synthesize multiple faces from the twin data. Here is the parameters. */ + +/* The following tables and matching code are copied from Pango */ + +/* CSS weight */ +typedef enum { + TWIN_WEIGHT_THIN = 100, + TWIN_WEIGHT_ULTRALIGHT = 200, + TWIN_WEIGHT_LIGHT = 300, + TWIN_WEIGHT_BOOK = 380, + TWIN_WEIGHT_NORMAL = 400, + TWIN_WEIGHT_MEDIUM = 500, + TWIN_WEIGHT_SEMIBOLD = 600, + TWIN_WEIGHT_BOLD = 700, + TWIN_WEIGHT_ULTRABOLD = 800, + TWIN_WEIGHT_HEAVY = 900, + TWIN_WEIGHT_ULTRAHEAVY = 1000 +} twin_face_weight_t; + +/* CSS stretch */ +typedef enum { + TWIN_STRETCH_ULTRA_CONDENSED, + TWIN_STRETCH_EXTRA_CONDENSED, + TWIN_STRETCH_CONDENSED, + TWIN_STRETCH_SEMI_CONDENSED, + TWIN_STRETCH_NORMAL, + TWIN_STRETCH_SEMI_EXPANDED, + TWIN_STRETCH_EXPANDED, + TWIN_STRETCH_EXTRA_EXPANDED, + TWIN_STRETCH_ULTRA_EXPANDED +} twin_face_stretch_t; + +typedef struct +{ + int value; + const char str[16]; +} FieldMap; + +static const FieldMap slant_map[] = { + { CAIRO_FONT_SLANT_NORMAL, "" }, + { CAIRO_FONT_SLANT_NORMAL, "Roman" }, + { CAIRO_FONT_SLANT_OBLIQUE, "Oblique" }, + { CAIRO_FONT_SLANT_ITALIC, "Italic" } +}; + +static const FieldMap smallcaps_map[] = { + { FALSE, "" }, + { TRUE, "Small-Caps" } +}; + +static const FieldMap weight_map[] = { + { TWIN_WEIGHT_THIN, "Thin" }, + { TWIN_WEIGHT_ULTRALIGHT, "Ultra-Light" }, + { TWIN_WEIGHT_ULTRALIGHT, "Extra-Light" }, + { TWIN_WEIGHT_LIGHT, "Light" }, + { TWIN_WEIGHT_BOOK, "Book" }, + { TWIN_WEIGHT_NORMAL, "" }, + { TWIN_WEIGHT_NORMAL, "Regular" }, + { TWIN_WEIGHT_MEDIUM, "Medium" }, + { TWIN_WEIGHT_SEMIBOLD, "Semi-Bold" }, + { TWIN_WEIGHT_SEMIBOLD, "Demi-Bold" }, + { TWIN_WEIGHT_BOLD, "Bold" }, + { TWIN_WEIGHT_ULTRABOLD, "Ultra-Bold" }, + { TWIN_WEIGHT_ULTRABOLD, "Extra-Bold" }, + { TWIN_WEIGHT_HEAVY, "Heavy" }, + { TWIN_WEIGHT_HEAVY, "Black" }, + { TWIN_WEIGHT_ULTRAHEAVY, "Ultra-Heavy" }, + { TWIN_WEIGHT_ULTRAHEAVY, "Extra-Heavy" }, + { TWIN_WEIGHT_ULTRAHEAVY, "Ultra-Black" }, + { TWIN_WEIGHT_ULTRAHEAVY, "Extra-Black" } +}; + +static const FieldMap stretch_map[] = { + { TWIN_STRETCH_ULTRA_CONDENSED, "Ultra-Condensed" }, + { TWIN_STRETCH_EXTRA_CONDENSED, "Extra-Condensed" }, + { TWIN_STRETCH_CONDENSED, "Condensed" }, + { TWIN_STRETCH_SEMI_CONDENSED, "Semi-Condensed" }, + { TWIN_STRETCH_NORMAL, "" }, + { TWIN_STRETCH_SEMI_EXPANDED, "Semi-Expanded" }, + { TWIN_STRETCH_EXPANDED, "Expanded" }, + { TWIN_STRETCH_EXTRA_EXPANDED, "Extra-Expanded" }, + { TWIN_STRETCH_ULTRA_EXPANDED, "Ultra-Expanded" } +}; + +static const FieldMap monospace_map[] = { + { FALSE, "" }, + { TRUE, "Mono" }, + { TRUE, "Monospace" } +}; + + +typedef struct _twin_face_properties { + cairo_font_slant_t slant; + twin_face_weight_t weight; + twin_face_stretch_t stretch; + + /* lets have some fun */ + cairo_bool_t monospace; + cairo_bool_t smallcaps; +} twin_face_properties_t; + +static cairo_bool_t +field_matches (const char *s1, + const char *s2, + int len) +{ + int c1, c2; + + while (len && *s1 && *s2) + { +#define TOLOWER(c) \ + (((c) >= 'A' && (c) <= 'Z') ? (c) - 'A' + 'a' : (c)) + + c1 = TOLOWER (*s1); + c2 = TOLOWER (*s2); + if (c1 != c2) { + if (c1 == '-') { + s1++; + continue; + } + return FALSE; + } + s1++; s2++; + len--; + } + + return len == 0 && *s1 == '\0'; +} + +static cairo_bool_t +parse_int (const char *word, + size_t wordlen, + int *out) +{ + char *end; + long val = strtol (word, &end, 10); + int i = val; + + if (end != word && (end == word + wordlen) && val >= 0 && val == i) + { + if (out) + *out = i; + + return TRUE; + } + + return FALSE; +} + +static cairo_bool_t +find_field (const char *what, + const FieldMap *map, + int n_elements, + const char *str, + int len, + int *val) +{ + int i; + cairo_bool_t had_prefix = FALSE; + + if (what) + { + i = strlen (what); + if (len > i && 0 == strncmp (what, str, i) && str[i] == '=') + { + str += i + 1; + len -= i + 1; + had_prefix = TRUE; + } + } + + for (i=0; i<n_elements; i++) + { + if (map[i].str[0] && field_matches (map[i].str, str, len)) + { + if (val) + *val = map[i].value; + return TRUE; + } + } + + if (!what || had_prefix) + return parse_int (str, len, val); + + return FALSE; +} + +static void +parse_field (twin_face_properties_t *props, + const char *str, + int len) +{ + if (field_matches ("Normal", str, len)) + return; + +#define FIELD(NAME) \ + if (find_field (STRINGIFY (NAME), NAME##_map, ARRAY_LENGTH (NAME##_map), str, len, \ + (int *)(void *)&props->NAME)) \ + return; \ + + FIELD (weight); + FIELD (slant); + FIELD (stretch); + FIELD (smallcaps); + FIELD (monospace); + +#undef FIELD +} + +static void +face_props_parse (twin_face_properties_t *props, + const char *s) +{ + const char *start, *end; + + for (start = end = s; *end; end++) { + if (*end != ' ' && *end != ':') + continue; + + if (start < end) + parse_field (props, start, end - start); + start = end + 1; + } + if (start < end) + parse_field (props, start, end - start); +} + +static twin_face_properties_t * +twin_font_face_create_properties (cairo_font_face_t *twin_face) +{ + twin_face_properties_t *props; + + props = _cairo_malloc (sizeof (twin_face_properties_t)); + if (unlikely (props == NULL)) + return NULL; + + props->stretch = TWIN_STRETCH_NORMAL; + props->slant = CAIRO_FONT_SLANT_NORMAL; + props->weight = TWIN_WEIGHT_NORMAL; + props->monospace = FALSE; + props->smallcaps = FALSE; + + if (unlikely (cairo_font_face_set_user_data (twin_face, + &twin_properties_key, + props, free))) { + free (props); + return NULL; + } + + return props; +} + +static cairo_status_t +twin_font_face_set_properties_from_toy (cairo_font_face_t *twin_face, + cairo_toy_font_face_t *toy_face) +{ + twin_face_properties_t *props; + + props = twin_font_face_create_properties (twin_face); + if (unlikely (props == NULL)) + return _cairo_error (CAIRO_STATUS_NO_MEMORY); + + props->slant = toy_face->slant; + props->weight = toy_face->weight == CAIRO_FONT_WEIGHT_NORMAL ? + TWIN_WEIGHT_NORMAL : TWIN_WEIGHT_BOLD; + face_props_parse (props, toy_face->family); + + return CAIRO_STATUS_SUCCESS; +} + + +/* + * Scaled properties + */ + +typedef struct _twin_scaled_properties { + twin_face_properties_t *face_props; + + cairo_bool_t snap; /* hint outlines */ + + double weight; /* unhinted pen width */ + double penx, peny; /* hinted pen width */ + double marginl, marginr; /* hinted side margins */ + + double stretch; /* stretch factor */ +} twin_scaled_properties_t; + +static void +compute_hinting_scale (cairo_t *cr, + double x, double y, + double *scale, double *inv) +{ + cairo_user_to_device_distance (cr, &x, &y); + *scale = x == 0 ? y : y == 0 ? x :sqrt (x*x + y*y); + *inv = 1 / *scale; +} + +static void +compute_hinting_scales (cairo_t *cr, + double *x_scale, double *x_scale_inv, + double *y_scale, double *y_scale_inv) +{ + double x, y; + + x = 1; y = 0; + compute_hinting_scale (cr, x, y, x_scale, x_scale_inv); + + x = 0; y = 1; + compute_hinting_scale (cr, x, y, y_scale, y_scale_inv); +} + +#define SNAPXI(p) (_cairo_round ((p) * x_scale) * x_scale_inv) +#define SNAPYI(p) (_cairo_round ((p) * y_scale) * y_scale_inv) + +/* This controls the global font size */ +#define F(g) ((g) / 72.) + +static void +twin_hint_pen_and_margins(cairo_t *cr, + double *penx, double *peny, + double *marginl, double *marginr) +{ + double x_scale, x_scale_inv; + double y_scale, y_scale_inv; + double margin; + + compute_hinting_scales (cr, + &x_scale, &x_scale_inv, + &y_scale, &y_scale_inv); + + *penx = SNAPXI (*penx); + if (*penx < x_scale_inv) + *penx = x_scale_inv; + + *peny = SNAPYI (*peny); + if (*peny < y_scale_inv) + *peny = y_scale_inv; + + margin = *marginl + *marginr; + *marginl = SNAPXI (*marginl); + if (*marginl < x_scale_inv) + *marginl = x_scale_inv; + + *marginr = margin - *marginl; + if (*marginr < 0) + *marginr = 0; + *marginr = SNAPXI (*marginr); +} + +static cairo_status_t +twin_scaled_font_compute_properties (cairo_scaled_font_t *scaled_font, + cairo_t *cr) +{ + cairo_status_t status; + twin_scaled_properties_t *props; + + props = _cairo_malloc (sizeof (twin_scaled_properties_t)); + if (unlikely (props == NULL)) + return _cairo_error (CAIRO_STATUS_NO_MEMORY); + + + props->face_props = cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font), + &twin_properties_key); + + props->snap = scaled_font->options.hint_style > CAIRO_HINT_STYLE_NONE; + + /* weight */ + props->weight = props->face_props->weight * (F (4) / TWIN_WEIGHT_NORMAL); + + /* pen & margins */ + props->penx = props->peny = props->weight; + props->marginl = props->marginr = F (4); + if (scaled_font->options.hint_style > CAIRO_HINT_STYLE_SLIGHT) + twin_hint_pen_and_margins(cr, + &props->penx, &props->peny, + &props->marginl, &props->marginr); + + /* stretch */ + props->stretch = 1 + .1 * ((int) props->face_props->stretch - (int) TWIN_STRETCH_NORMAL); + + + /* Save it */ + status = cairo_scaled_font_set_user_data (scaled_font, + &twin_properties_key, + props, free); + if (unlikely (status)) + goto FREE_PROPS; + + return CAIRO_STATUS_SUCCESS; + +FREE_PROPS: + free (props); + return status; +} + + +/* + * User-font implementation + */ + +static cairo_status_t +twin_scaled_font_init (cairo_scaled_font_t *scaled_font, + cairo_t *cr, + cairo_font_extents_t *metrics) +{ + metrics->ascent = F (54); + metrics->descent = 1 - metrics->ascent; + + return twin_scaled_font_compute_properties (scaled_font, cr); +} + +#define TWIN_GLYPH_MAX_SNAP_X 4 +#define TWIN_GLYPH_MAX_SNAP_Y 7 + +typedef struct { + int n_snap_x; + int8_t snap_x[TWIN_GLYPH_MAX_SNAP_X]; + double snapped_x[TWIN_GLYPH_MAX_SNAP_X]; + int n_snap_y; + int8_t snap_y[TWIN_GLYPH_MAX_SNAP_Y]; + double snapped_y[TWIN_GLYPH_MAX_SNAP_Y]; +} twin_snap_info_t; + +#define twin_glyph_left(g) ((g)[0]) +#define twin_glyph_right(g) ((g)[1]) +#define twin_glyph_ascent(g) ((g)[2]) +#define twin_glyph_descent(g) ((g)[3]) + +#define twin_glyph_n_snap_x(g) ((g)[4]) +#define twin_glyph_n_snap_y(g) ((g)[5]) +#define twin_glyph_snap_x(g) (&g[6]) +#define twin_glyph_snap_y(g) (twin_glyph_snap_x(g) + twin_glyph_n_snap_x(g)) +#define twin_glyph_draw(g) (twin_glyph_snap_y(g) + twin_glyph_n_snap_y(g)) + +static void +twin_compute_snap (cairo_t *cr, + twin_snap_info_t *info, + const signed char *b) +{ + int s, n; + const signed char *snap; + double x_scale, x_scale_inv; + double y_scale, y_scale_inv; + + compute_hinting_scales (cr, + &x_scale, &x_scale_inv, + &y_scale, &y_scale_inv); + + snap = twin_glyph_snap_x (b); + n = twin_glyph_n_snap_x (b); + info->n_snap_x = n; + assert (n <= TWIN_GLYPH_MAX_SNAP_X); + for (s = 0; s < n; s++) { + info->snap_x[s] = snap[s]; + info->snapped_x[s] = SNAPXI (F (snap[s])); + } + + snap = twin_glyph_snap_y (b); + n = twin_glyph_n_snap_y (b); + info->n_snap_y = n; + assert (n <= TWIN_GLYPH_MAX_SNAP_Y); + for (s = 0; s < n; s++) { + info->snap_y[s] = snap[s]; + info->snapped_y[s] = SNAPYI (F (snap[s])); + } +} + +static double +twin_snap (int8_t v, int n, int8_t *snap, double *snapped) +{ + int s; + + if (!n) + return F(v); + + if (snap[0] == v) + return snapped[0]; + + for (s = 0; s < n - 1; s++) + { + if (snap[s+1] == v) + return snapped[s+1]; + + if (snap[s] <= v && v <= snap[s+1]) + { + int before = snap[s]; + int after = snap[s+1]; + int dist = after - before; + double snap_before = snapped[s]; + double snap_after = snapped[s+1]; + double dist_before = v - before; + return snap_before + (snap_after - snap_before) * dist_before / dist; + } + } + return F(v); +} + +#define SNAPX(p) twin_snap (p, info.n_snap_x, info.snap_x, info.snapped_x) +#define SNAPY(p) twin_snap (p, info.n_snap_y, info.snap_y, info.snapped_y) + +static cairo_status_t +twin_scaled_font_render_glyph (cairo_scaled_font_t *scaled_font, + unsigned long glyph, + cairo_t *cr, + cairo_text_extents_t *metrics) +{ + double x1, y1, x2, y2, x3, y3; + double marginl; + twin_scaled_properties_t *props; + twin_snap_info_t info; + const int8_t *b; + const int8_t *g; + int8_t w; + double gw; + + props = cairo_scaled_font_get_user_data (scaled_font, &twin_properties_key); + + /* Save glyph space, we need it when stroking */ + cairo_save (cr); + + /* center the pen */ + cairo_translate (cr, props->penx * .5, -props->peny * .5); + + /* small-caps */ + if (props->face_props->smallcaps && glyph >= 'a' && glyph <= 'z') { + glyph += 'A' - 'a'; + /* 28 and 42 are small and capital letter heights of the glyph data */ + cairo_scale (cr, 1, 28. / 42); + } + + /* slant */ + if (props->face_props->slant != CAIRO_FONT_SLANT_NORMAL) { + cairo_matrix_t shear = { 1, 0, -.2, 1, 0, 0}; + cairo_transform (cr, &shear); + } + + b = _cairo_twin_outlines + + _cairo_twin_charmap[unlikely (glyph >= ARRAY_LENGTH (_cairo_twin_charmap)) ? 0 : glyph]; + g = twin_glyph_draw(b); + w = twin_glyph_right(b); + gw = F(w); + + marginl = props->marginl; + + /* monospace */ + if (props->face_props->monospace) { + double monow = F(24); + double extra = props->penx + props->marginl + props->marginr; + cairo_scale (cr, (monow + extra) / (gw + extra), 1); + gw = monow; + + /* resnap margin for new transform */ + { + double x, y, x_scale, x_scale_inv; + x = 1; y = 0; + compute_hinting_scale (cr, x, y, &x_scale, &x_scale_inv); + marginl = SNAPXI (marginl); + } + } + + cairo_translate (cr, marginl, 0); + + /* stretch */ + cairo_scale (cr, props->stretch, 1); + + if (props->snap) + twin_compute_snap (cr, &info, b); + else + info.n_snap_x = info.n_snap_y = 0; + + /* advance width */ + metrics->x_advance = gw * props->stretch + props->penx + props->marginl + props->marginr; + + /* glyph shape */ + for (;;) { + switch (*g++) { + case 'M': + cairo_close_path (cr); + /* fall through */ + case 'm': + x1 = SNAPX(*g++); + y1 = SNAPY(*g++); + cairo_move_to (cr, x1, y1); + continue; + case 'L': + cairo_close_path (cr); + /* fall through */ + case 'l': + x1 = SNAPX(*g++); + y1 = SNAPY(*g++); + cairo_line_to (cr, x1, y1); + continue; + case 'C': + cairo_close_path (cr); + /* fall through */ + case 'c': + x1 = SNAPX(*g++); + y1 = SNAPY(*g++); + x2 = SNAPX(*g++); + y2 = SNAPY(*g++); + x3 = SNAPX(*g++); + y3 = SNAPY(*g++); + cairo_curve_to (cr, x1, y1, x2, y2, x3, y3); + continue; + case 'E': + cairo_close_path (cr); + /* fall through */ + case 'e': + cairo_restore (cr); /* restore glyph space */ + cairo_set_tolerance (cr, 0.01); + cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND); + cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND); + cairo_set_line_width (cr, 1); + cairo_scale (cr, props->penx, props->peny); + cairo_stroke (cr); + break; + case 'X': + /* filler */ + continue; + } + break; + } + + return CAIRO_STATUS_SUCCESS; +} + +static cairo_status_t +twin_scaled_font_unicode_to_glyph (cairo_scaled_font_t *scaled_font, + unsigned long unicode, + unsigned long *glyph) +{ + /* We use an identity charmap. Which means we could live + * with no unicode_to_glyph method too. But we define this + * to map all unknown chars to a single unknown glyph to + * reduce pressure on cache. */ + + if (likely (unicode < ARRAY_LENGTH (_cairo_twin_charmap))) + *glyph = unicode; + else + *glyph = 0; + + return CAIRO_STATUS_SUCCESS; +} + + +/* + * Face constructor + */ + +static cairo_font_face_t * +_cairo_font_face_twin_create_internal (void) +{ + cairo_font_face_t *twin_font_face; + + twin_font_face = cairo_user_font_face_create (); + cairo_user_font_face_set_init_func (twin_font_face, twin_scaled_font_init); + cairo_user_font_face_set_render_glyph_func (twin_font_face, twin_scaled_font_render_glyph); + cairo_user_font_face_set_unicode_to_glyph_func (twin_font_face, twin_scaled_font_unicode_to_glyph); + + return twin_font_face; +} + +cairo_font_face_t * +_cairo_font_face_twin_create_fallback (void) +{ + cairo_font_face_t *twin_font_face; + + twin_font_face = _cairo_font_face_twin_create_internal (); + if (! twin_font_face_create_properties (twin_font_face)) { + cairo_font_face_destroy (twin_font_face); + return (cairo_font_face_t *) &_cairo_font_face_nil; + } + + return twin_font_face; +} + +cairo_status_t +_cairo_font_face_twin_create_for_toy (cairo_toy_font_face_t *toy_face, + cairo_font_face_t **font_face) +{ + cairo_status_t status; + cairo_font_face_t *twin_font_face; + + twin_font_face = _cairo_font_face_twin_create_internal (); + status = twin_font_face_set_properties_from_toy (twin_font_face, toy_face); + if (status) { + cairo_font_face_destroy (twin_font_face); + return status; + } + + *font_face = twin_font_face; + + return CAIRO_STATUS_SUCCESS; +} |