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/*
* 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 = 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 = 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;
}