PIKApp/libpikacolor/pikargb-parse.c

650 lines
19 KiB
C

/* LIBPIKA - The PIKA Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* pikargb-parse.c
* Copyright (C) 2004 Sven Neumann <sven@gimp.org>
*
* Some of the code in here was inspired and partly copied from pango
* and librsvg.
*
* This library is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <babl/babl.h>
#include <glib-object.h>
#include "pikacolortypes.h"
#include "pikacolorspace.h"
#include "pikargb.h"
static gchar * pika_rgb_parse_strip (const gchar *str,
gint len);
static gboolean pika_rgb_parse_name_internal (PikaRGB *rgb,
const gchar *name);
static gboolean pika_rgb_parse_hex_internal (PikaRGB *rgb,
const gchar *hex);
static gboolean pika_rgb_parse_css_internal (PikaRGB *rgb,
const gchar *css);
static gboolean pika_rgba_parse_css_internal (PikaRGB *rgb,
const gchar *css);
typedef struct
{
const gchar *name;
const guchar red;
const guchar green;
const guchar blue;
} ColorEntry;
static const ColorEntry named_colors[] =
{
{ "aliceblue", 240, 248, 255 },
{ "antiquewhite", 250, 235, 215 },
{ "aqua", 0, 255, 255 },
{ "aquamarine", 127, 255, 212 },
{ "azure", 240, 255, 255 },
{ "beige", 245, 245, 220 },
{ "bisque", 255, 228, 196 },
{ "black", 0, 0, 0 },
{ "blanchedalmond", 255, 235, 205 },
{ "blue", 0, 0, 255 },
{ "blueviolet", 138, 43, 226 },
{ "brown", 165, 42, 42 },
{ "burlywood", 222, 184, 135 },
{ "cadetblue", 95, 158, 160 },
{ "chartreuse", 127, 255, 0 },
{ "chocolate", 210, 105, 30 },
{ "coral", 255, 127, 80 },
{ "cornflowerblue", 100, 149, 237 },
{ "cornsilk", 255, 248, 220 },
{ "crimson", 220, 20, 60 },
{ "cyan", 0, 255, 255 },
{ "darkblue", 0, 0, 139 },
{ "darkcyan", 0, 139, 139 },
{ "darkgoldenrod", 184, 134, 11 },
{ "darkgray", 169, 169, 169 },
{ "darkgreen", 0, 100, 0 },
{ "darkgrey", 169, 169, 169 },
{ "darkkhaki", 189, 183, 107 },
{ "darkmagenta", 139, 0, 139 },
{ "darkolivegreen", 85, 107, 47 },
{ "darkorange", 255, 140, 0 },
{ "darkorchid", 153, 50, 204 },
{ "darkred", 139, 0, 0 },
{ "darksalmon", 233, 150, 122 },
{ "darkseagreen", 143, 188, 143 },
{ "darkslateblue", 72, 61, 139 },
{ "darkslategray", 47, 79, 79 },
{ "darkslategrey", 47, 79, 79 },
{ "darkturquoise", 0, 206, 209 },
{ "darkviolet", 148, 0, 211 },
{ "deeppink", 255, 20, 147 },
{ "deepskyblue", 0, 191, 255 },
{ "dimgray", 105, 105, 105 },
{ "dimgrey", 105, 105, 105 },
{ "dodgerblue", 30, 144, 255 },
{ "firebrick", 178, 34, 34 },
{ "floralwhite" , 255, 250, 240 },
{ "forestgreen", 34, 139, 34 },
{ "fuchsia", 255, 0, 255 },
{ "gainsboro", 220, 220, 220 },
{ "ghostwhite", 248, 248, 255 },
{ "gold", 255, 215, 0 },
{ "goldenrod", 218, 165, 32 },
{ "gray", 128, 128, 128 },
{ "green", 0, 128, 0 },
{ "greenyellow", 173, 255, 47 },
{ "grey", 128, 128, 128 },
{ "honeydew", 240, 255, 240 },
{ "hotpink", 255, 105, 180 },
{ "indianred", 205, 92, 92 },
{ "indigo", 75, 0, 130 },
{ "ivory", 255, 255, 240 },
{ "khaki", 240, 230, 140 },
{ "lavender", 230, 230, 250 },
{ "lavenderblush", 255, 240, 245 },
{ "lawngreen", 124, 252, 0 },
{ "lemonchiffon", 255, 250, 205 },
{ "lightblue", 173, 216, 230 },
{ "lightcoral", 240, 128, 128 },
{ "lightcyan", 224, 255, 255 },
{ "lightgoldenrodyellow", 250, 250, 210 },
{ "lightgray", 211, 211, 211 },
{ "lightgreen", 144, 238, 144 },
{ "lightgrey", 211, 211, 211 },
{ "lightpink", 255, 182, 193 },
{ "lightsalmon", 255, 160, 122 },
{ "lightseagreen", 32, 178, 170 },
{ "lightskyblue", 135, 206, 250 },
{ "lightslategray", 119, 136, 153 },
{ "lightslategrey", 119, 136, 153 },
{ "lightsteelblue", 176, 196, 222 },
{ "lightyellow", 255, 255, 224 },
{ "lime", 0, 255, 0 },
{ "limegreen", 50, 205, 50 },
{ "linen", 250, 240, 230 },
{ "magenta", 255, 0, 255 },
{ "maroon", 128, 0, 0 },
{ "mediumaquamarine", 102, 205, 170 },
{ "mediumblue", 0, 0, 205 },
{ "mediumorchid", 186, 85, 211 },
{ "mediumpurple", 147, 112, 219 },
{ "mediumseagreen", 60, 179, 113 },
{ "mediumslateblue", 123, 104, 238 },
{ "mediumspringgreen", 0, 250, 154 },
{ "mediumturquoise", 72, 209, 204 },
{ "mediumvioletred", 199, 21, 133 },
{ "midnightblue", 25, 25, 112 },
{ "mintcream", 245, 255, 250 },
{ "mistyrose", 255, 228, 225 },
{ "moccasin", 255, 228, 181 },
{ "navajowhite", 255, 222, 173 },
{ "navy", 0, 0, 128 },
{ "oldlace", 253, 245, 230 },
{ "olive", 128, 128, 0 },
{ "olivedrab", 107, 142, 35 },
{ "orange", 255, 165, 0 },
{ "orangered", 255, 69, 0 },
{ "orchid", 218, 112, 214 },
{ "palegoldenrod", 238, 232, 170 },
{ "palegreen", 152, 251, 152 },
{ "paleturquoise", 175, 238, 238 },
{ "palevioletred", 219, 112, 147 },
{ "papayawhip", 255, 239, 213 },
{ "peachpuff", 255, 218, 185 },
{ "peru", 205, 133, 63 },
{ "pink", 255, 192, 203 },
{ "plum", 221, 160, 221 },
{ "powderblue", 176, 224, 230 },
{ "purple", 128, 0, 128 },
{ "red", 255, 0, 0 },
{ "rosybrown", 188, 143, 143 },
{ "royalblue", 65, 105, 225 },
{ "saddlebrown", 139, 69, 19 },
{ "salmon", 250, 128, 114 },
{ "sandybrown", 244, 164, 96 },
{ "seagreen", 46, 139, 87 },
{ "seashell", 255, 245, 238 },
{ "sienna", 160, 82, 45 },
{ "silver", 192, 192, 192 },
{ "skyblue", 135, 206, 235 },
{ "slateblue", 106, 90, 205 },
{ "slategray", 112, 128, 144 },
{ "slategrey", 112, 128, 144 },
{ "snow", 255, 250, 250 },
{ "springgreen", 0, 255, 127 },
{ "steelblue", 70, 130, 180 },
{ "tan", 210, 180, 140 },
{ "teal", 0, 128, 128 },
{ "thistle", 216, 191, 216 },
{ "tomato", 255, 99, 71 },
{ "turquoise", 64, 224, 208 },
{ "violet", 238, 130, 238 },
{ "wheat", 245, 222, 179 },
{ "white", 255, 255, 255 },
{ "whitesmoke", 245, 245, 245 },
{ "yellow", 255, 255, 0 },
{ "yellowgreen", 154, 205, 50 }
};
/**
* pika_rgb_parse_name:
* @rgb: a #PikaRGB struct used to return the parsed color
* @name: (array length=len): a color name (in UTF-8 encoding)
* @len: the length of @name, in bytes. or -1 if @name is nul-terminated
*
* Attempts to parse a color name. This function accepts <ulink
* url="https://www.w3.org/TR/SVG/types.html#ColorKeywords">SVG 1.0
* color keywords</ulink>.
*
* This function does not touch the alpha component of @rgb.
*
* Returns: %TRUE if @name was parsed successfully and @rgb has
* been set, %FALSE otherwise
*
* Since: 2.2
**/
gboolean
pika_rgb_parse_name (PikaRGB *rgb,
const gchar *name,
gint len)
{
gchar *tmp;
gboolean result;
g_return_val_if_fail (rgb != NULL, FALSE);
g_return_val_if_fail (name != NULL, FALSE);
tmp = pika_rgb_parse_strip (name, len);
result = pika_rgb_parse_name_internal (rgb, tmp);
g_free (tmp);
return result;
}
/**
* pika_rgb_parse_hex:
* @rgb: a #PikaRGB struct used to return the parsed color
* @hex: (array length=len): a string describing a color in hexadecimal notation
* @len: the length of @hex, in bytes. or -1 if @hex is nul-terminated
*
* Attempts to parse a string describing an RGB color in hexadecimal
* notation (optionally prefixed with a '#').
*
* This function does not touch the alpha component of @rgb.
*
* Returns: %TRUE if @hex was parsed successfully and @rgb has
* been set, %FALSE otherwise
*
* Since: 2.2
**/
gboolean
pika_rgb_parse_hex (PikaRGB *rgb,
const gchar *hex,
gint len)
{
gchar *tmp;
gboolean result;
g_return_val_if_fail (rgb != NULL, FALSE);
g_return_val_if_fail (hex != NULL, FALSE);
tmp = pika_rgb_parse_strip (hex, len);
result = pika_rgb_parse_hex_internal (rgb, tmp);
g_free (tmp);
return result;
}
/**
* pika_rgb_parse_css:
* @rgb: a #PikaRGB struct used to return the parsed color
* @css: (array length=len): a string describing a color in CSS notation
* @len: the length of @css, in bytes. or -1 if @css is nul-terminated
*
* Attempts to parse a string describing an RGB color in CSS
* notation. This can be either a numerical representation
* (<code>rgb(255,0,0)</code> or <code>rgb(100%,0%,0%)</code>)
* or a hexadecimal notation as parsed by pika_rgb_parse_hex()
* (<code>##ff0000</code>) or a color name as parsed by
* pika_rgb_parse_name() (<code>red</code>).
*
* This function does not touch the alpha component of @rgb.
*
* Returns: %TRUE if @css was parsed successfully and @rgb has been
* set, %FALSE otherwise
*
* Since: 2.2
**/
gboolean
pika_rgb_parse_css (PikaRGB *rgb,
const gchar *css,
gint len)
{
gchar *tmp;
gboolean result;
g_return_val_if_fail (rgb != NULL, FALSE);
g_return_val_if_fail (css != NULL, FALSE);
tmp = pika_rgb_parse_strip (css, len);
result = pika_rgb_parse_css_internal (rgb, tmp);
g_free (tmp);
return result;
}
/**
* pika_rgba_parse_css:
* @rgba: a #PikaRGB struct used to return the parsed color
* @css: (array length=len): a string describing a color in CSS notation
* @len: the length of @css, in bytes. or -1 if @css is nul-terminated
*
* Similar to pika_rgb_parse_css() but handles RGB colors with alpha
* channel in the numerical CSS notation (<code>rgba(255,0,0,255)</code>
* or <code>rgba(100%,0%,0%,1000%)</code>).
*
* It doesn't handle the hexadecimal notation or color names because
* they leave the alpha channel unspecified.
*
* Returns: %TRUE if @css was parsed successfully and @rgb has been
* set, %FALSE otherwise
*
* Since: 2.2
**/
gboolean
pika_rgba_parse_css (PikaRGB *rgba,
const gchar *css,
gint len)
{
gchar *tmp;
gboolean result;
g_return_val_if_fail (rgba != NULL, FALSE);
g_return_val_if_fail (css != NULL, FALSE);
if (len < 0)
len = strlen (css);
tmp = pika_rgb_parse_strip (css, len);
if (strcmp (tmp, "transparent") == 0)
{
pika_rgba_set (rgba, 0.0, 0.0, 0.0, 0.0);
result = TRUE;
}
else
{
result = pika_rgba_parse_css_internal (rgba, tmp);
}
g_free (tmp);
return result;
}
/**
* pika_rgb_list_names:
* @names: (out) (array length=n_colors) (transfer container): return location for an array of color names
* @colors: (out) (array length=n_colors) (transfer container): return location for an array of PikaRGB structs
* @n_colors: (out): The number of named colors
*
* Returns the list of <ulink
* url="https://www.w3.org/TR/SVG/types.html">SVG 1.0 color
* keywords</ulink> that is used by pika_rgb_parse_name().
*
* The returned strings are const and must not be freed. Only the two
* arrays are allocated dynamically. You must call g_free() on the
* @names and @colors arrays when they are not any longer needed.
*
* Since: 2.2
**/
void
pika_rgb_list_names (const gchar ***names,
PikaRGB **colors,
gint *n_colors)
{
gint i;
g_return_if_fail (names != NULL);
g_return_if_fail (colors != NULL);
g_return_if_fail (n_colors != NULL);
*names = g_new (const gchar *, G_N_ELEMENTS (named_colors));
*colors = g_new (PikaRGB, G_N_ELEMENTS (named_colors));
*n_colors = G_N_ELEMENTS (named_colors);
for (i = 0; i < G_N_ELEMENTS (named_colors); i++)
{
(*names)[i] = named_colors[i].name;
pika_rgba_set_uchar ((*colors) + i,
named_colors[i].red,
named_colors[i].green,
named_colors[i].blue,
0xFF);
}
}
static gchar *
pika_rgb_parse_strip (const gchar *str,
gint len)
{
gchar *result;
while (len > 0 && g_ascii_isspace (*str))
{
str++;
len--;
}
if (len < 0)
{
while (g_ascii_isspace (*str))
str++;
len = strlen (str);
}
while (len > 0 && g_ascii_isspace (str[len - 1]))
len--;
result = g_malloc (len + 1);
memcpy (result, str, len);
result[len] = '\0';
return result;
}
static gint
pika_rgb_color_entry_compare (gconstpointer a,
gconstpointer b)
{
const gchar *name = a;
const ColorEntry *entry = b;
return g_ascii_strcasecmp (name, entry->name);
}
static gboolean
pika_rgb_parse_name_internal (PikaRGB *rgb,
const gchar *name)
{
ColorEntry *entry = bsearch (name, named_colors,
G_N_ELEMENTS (named_colors), sizeof (ColorEntry),
pika_rgb_color_entry_compare);
if (entry)
{
pika_rgb_set_uchar (rgb, entry->red, entry->green, entry->blue);
return TRUE;
}
return FALSE;
}
static gboolean
pika_rgb_parse_hex_component (const gchar *hex,
gint len,
gdouble *value)
{
gint i;
guint c = 0;
for (i = 0; i < len; i++, hex++)
{
if (!*hex || !g_ascii_isxdigit (*hex))
return FALSE;
c = (c << 4) | g_ascii_xdigit_value (*hex);
}
switch (len)
{
case 1: *value = (gdouble) c / 15.0; break;
case 2: *value = (gdouble) c / 255.0; break;
case 3: *value = (gdouble) c / 4095.0; break;
case 4: *value = (gdouble) c / 65535.0; break;
default:
g_return_val_if_reached (FALSE);
}
return TRUE;
}
static gboolean
pika_rgb_parse_hex_internal (PikaRGB *rgb,
const gchar *hex)
{
gint i;
gsize len;
gdouble val[3];
if (hex[0] == '#')
hex++;
len = strlen (hex);
if (len % 3 || len < 3 || len > 12)
return FALSE;
len /= 3;
for (i = 0; i < 3; i++, hex += len)
{
if (! pika_rgb_parse_hex_component (hex, len, val + i))
return FALSE;
}
pika_rgb_set (rgb, val[0], val[1], val[2]);
return TRUE;
}
static gboolean
pika_rgb_parse_css_numeric (PikaRGB *rgb,
const gchar *css)
{
gdouble values[4];
gboolean alpha;
gboolean hsl;
gint i;
if (css[0] == 'r' && css[1] == 'g' && css[2] == 'b')
hsl = FALSE;
else if (css[0] == 'h' && css[1] == 's' && css[2] == 'l')
hsl = TRUE;
else
return FALSE;
if (css[3] == 'a' && css[4] == '(')
alpha = TRUE;
else if (css[3] == '(')
alpha = FALSE;
else
return FALSE;
css += (alpha ? 5 : 4);
for (i = 0; i < (alpha ? 4 : 3); i++)
{
const gchar *end = css;
while (*end && *end != ',' && *end != '%' && *end != ')')
end++;
if (i == 3 || *end == '%')
{
values[i] = g_ascii_strtod (css, (gchar **) &end);
if (errno == ERANGE)
return FALSE;
if (*end == '%')
{
end++;
values[i] /= 100.0;
}
}
else
{
glong value = strtol (css, (gchar **) &end, 10);
if (errno == ERANGE)
return FALSE;
if (hsl)
values[i] = value / (i == 0 ? 360.0 : 100.0);
else
values[i] = value / 255.0;
}
while (*end == ',' || g_ascii_isspace (*end))
end++;
css = end;
}
if (*css != ')')
return FALSE;
if (alpha)
pika_rgba_set (rgb, values[0], values[1], values[2], values[3]);
else
pika_rgb_set (rgb, values[0], values[1], values[2]);
pika_rgb_clamp (rgb);
if (hsl)
{
PikaHSL tmp = (*((PikaHSL *) rgb));
pika_hsl_to_rgb (&tmp, rgb);
}
return TRUE;
}
static gboolean
pika_rgb_parse_css_internal (PikaRGB *rgb,
const gchar *css)
{
if (css[0] == '#')
{
return pika_rgb_parse_hex_internal (rgb, css);
}
else if (strncmp (css, "rgb(", 4) == 0 ||
strncmp (css, "hsl(", 4) == 0)
{
return pika_rgb_parse_css_numeric (rgb, css);
}
else
{
return pika_rgb_parse_name_internal (rgb, css);
}
}
static gboolean
pika_rgba_parse_css_internal (PikaRGB *rgba,
const gchar *css)
{
if (strncmp (css, "rgba(", 5) != 0 &&
strncmp (css, "hsla(", 5) != 0)
return FALSE;
return pika_rgb_parse_css_numeric (rgba, css);
}