4 * An OpenGL based 'interactive canvas' library.
6 * Authored By Matthew Allum <mallum@openedhand.com>
8 * Copyright (C) 2006 OpenedHand
10 * This library is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with this library; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 02111-1307, USA.
27 * SECTION:clutter-color
28 * @short_description: Color management and manipulation.
30 * #ClutterColor is a simple type for representing colors in Clutter.
32 * A #ClutterColor is expressed as a 4-tuple of values ranging from
33 * zero to 255, one for each color channel plus one for the alpha.
35 * The alpha channel is fully opaque at 255 and fully transparent at 0.
42 #include <pango/pango-attributes.h>
43 #include <gobject/gvaluecollector.h>
45 #include "clutter-main.h"
46 #include "clutter-color.h"
47 #include "clutter-private.h"
48 #include "clutter-debug.h"
54 * @result: (out): return location for the result
56 * Adds @a to @b and saves the resulting color inside @result.
58 * The alpha channel of @result is set as as the maximum value
59 * between the alpha channels of @a and @b.
62 clutter_color_add (const ClutterColor *a,
63 const ClutterColor *b,
66 g_return_if_fail (a != NULL);
67 g_return_if_fail (b != NULL);
68 g_return_if_fail (result != NULL);
70 result->red = CLAMP (a->red + b->red, 0, 255);
71 result->green = CLAMP (a->green + b->green, 0, 255);
72 result->blue = CLAMP (a->blue + b->blue, 0, 255);
74 result->alpha = MAX (a->alpha, b->alpha);
78 * clutter_color_subtract:
81 * @result: (out): return location for the result
83 * Subtracts @b from @a and saves the resulting color inside @result.
85 * This function assumes that the components of @a are greater than the
86 * components of @b; the result is, otherwise, undefined.
88 * The alpha channel of @result is set as the minimum value
89 * between the alpha channels of @a and @b.
92 clutter_color_subtract (const ClutterColor *a,
93 const ClutterColor *b,
96 g_return_if_fail (a != NULL);
97 g_return_if_fail (b != NULL);
98 g_return_if_fail (result != NULL);
100 result->red = CLAMP (a->red - b->red, 0, 255);
101 result->green = CLAMP (a->green - b->green, 0, 255);
102 result->blue = CLAMP (a->blue - b->blue, 0, 255);
104 result->alpha = MIN (a->alpha, b->alpha);
108 * clutter_color_lighten:
109 * @color: a #ClutterColor
110 * @result: (out): return location for the lighter color
112 * Lightens @color by a fixed amount, and saves the changed color
116 clutter_color_lighten (const ClutterColor *color,
117 ClutterColor *result)
119 clutter_color_shade (color, 1.3, result);
123 * clutter_color_darken:
124 * @color: a #ClutterColor
125 * @result: (out): return location for the darker color
127 * Darkens @color by a fixed amount, and saves the changed color
131 clutter_color_darken (const ClutterColor *color,
132 ClutterColor *result)
134 clutter_color_shade (color, 0.7, result);
138 * clutter_color_to_hls:
139 * @color: a #ClutterColor
140 * @hue: return location for the hue value or %NULL
141 * @luminance: return location for the luminance value or %NULL
142 * @saturation: return location for the saturation value or %NULL
144 * Converts @color to the HLS format.
146 * The @hue value is in the 0 .. 360 range. The @luminance and
147 * @saturation values are in the 0 .. 1 range.
150 clutter_color_to_hls (const ClutterColor *color,
155 float red, green, blue;
156 float min, max, delta;
159 g_return_if_fail (color != NULL);
161 red = color->red / 255.0;
162 green = color->green / 255.0;
163 blue = color->blue / 255.0;
197 s = (max - min) / (max + min);
199 s = (max - min) / (2.0 - max - min);
204 h = (green - blue) / delta;
205 else if (green == max)
206 h = 2.0 + (blue - red) / delta;
207 else if (blue == max)
208 h = 4.0 + (red - green) / delta;
227 * clutter_color_from_hls:
228 * @color: (out): return location for a #ClutterColor
229 * @hue: hue value, in the 0 .. 360 range
230 * @luminance: luminance value, in the 0 .. 1 range
231 * @saturation: saturation value, in the 0 .. 1 range
233 * Converts a color expressed in HLS (hue, luminance and saturation)
234 * values into a #ClutterColor.
237 clutter_color_from_hls (ClutterColor *color,
251 color->red = color->green = color->blue = (luminance * 255);
256 if (luminance <= 0.5)
257 tmp2 = luminance * (1.0 + saturation);
259 tmp2 = luminance + saturation - (luminance * saturation);
261 tmp1 = 2.0 * luminance - tmp2;
263 tmp3[0] = hue + 1.0 / 3.0;
265 tmp3[2] = hue - 1.0 / 3.0;
267 for (i = 0; i < 3; i++)
275 if (6.0 * tmp3[i] < 1.0)
276 clr[i] = tmp1 + (tmp2 - tmp1) * tmp3[i] * 6.0;
277 else if (2.0 * tmp3[i] < 1.0)
279 else if (3.0 * tmp3[i] < 2.0)
280 clr[i] = (tmp1 + (tmp2 - tmp1) * ((2.0 / 3.0) - tmp3[i]) * 6.0);
285 color->red = clr[0] * 255.0;
286 color->green = clr[1] * 255.0;
287 color->blue = clr[2] * 255.0;
291 * clutter_color_shade:
292 * @color: a #ClutterColor
293 * @factor: the shade factor to apply
294 * @result: (out): return location for the shaded color
296 * Shades @color by @factor and saves the modified color into @result.
299 clutter_color_shade (const ClutterColor *color,
301 ClutterColor *result)
305 g_return_if_fail (color != NULL);
306 g_return_if_fail (result != NULL);
308 clutter_color_to_hls (color, &h, &l, &s);
322 clutter_color_from_hls (result, h, l, s);
324 result->alpha = color->alpha;
328 * clutter_color_to_pixel:
329 * @color: a #ClutterColor
331 * Converts @color into a packed 32 bit integer, containing
332 * all the four 8 bit channels used by #ClutterColor.
334 * Return value: a packed color
337 clutter_color_to_pixel (const ClutterColor *color)
339 g_return_val_if_fail (color != NULL, 0);
341 return (color->alpha |
348 * clutter_color_from_pixel:
349 * @color: (out): return location for a #ClutterColor
350 * @pixel: a 32 bit packed integer containing a color
352 * Converts @pixel from the packed representation of a four 8 bit channel
353 * color to a #ClutterColor.
356 clutter_color_from_pixel (ClutterColor *color,
359 g_return_if_fail (color != NULL);
361 color->red = pixel >> 24;
362 color->green = (pixel >> 16) & 0xff;
363 color->blue = (pixel >> 8) & 0xff;
364 color->alpha = pixel & 0xff;
368 * clutter_color_from_string:
369 * @color: (out): return location for a #ClutterColor
370 * @str: a string specifiying a color (named color or #RRGGBBAA)
372 * Parses a string definition of a color, filling the
373 * <structfield>red</structfield>, <structfield>green</structfield>,
374 * <structfield>blue</structfield> and <structfield>alpha</structfield>
375 * channels of @color. If alpha is not specified it will be set full opaque.
377 * The @color is not allocated.
379 * The color may be defined by any of the formats understood by
380 * pango_color_from_string(); these include literal color names, like
381 * <literal>Red</literal> or <literal>DarkSlateGray</literal>, or
382 * hexadecimal specifications like <literal>#3050b2</literal> or
383 * <literal>#333</literal>.
385 * Return value: %TRUE if parsing succeeded.
390 clutter_color_from_string (ClutterColor *color,
393 PangoColor pango_color = { 0, };
395 g_return_val_if_fail (color != NULL, FALSE);
396 g_return_val_if_fail (str != NULL, FALSE);
398 /* if the string contains a color encoded using the hexadecimal
399 * notations (#rrggbbaa or #rgba) we attempt a rough pass at
400 * parsing the color ourselves, as we need the alpha channel that
401 * Pango can't retrieve.
407 if (sscanf (str + 1, "%x", &result))
409 if (strlen (str) == 9)
412 color->red = (result >> 24) & 0xff;
413 color->green = (result >> 16) & 0xff;
414 color->blue = (result >> 8) & 0xff;
416 color->alpha = result & 0xff;
420 else if (strlen (str) == 5)
423 color->red = ((result >> 12) & 0xf);
424 color->green = ((result >> 8) & 0xf);
425 color->blue = ((result >> 4) & 0xf);
426 color->alpha = result & 0xf;
428 color->red = (color->red << 4) | color->red;
429 color->green = (color->green << 4) | color->green;
430 color->blue = (color->blue << 4) | color->blue;
431 color->alpha = (color->alpha << 4) | color->alpha;
438 /* Fall back to pango for named colors */
439 if (pango_color_parse (&pango_color, str))
441 color->red = pango_color.red;
442 color->green = pango_color.green;
443 color->blue = pango_color.blue;
454 * clutter_color_to_string:
455 * @color: a #ClutterColor
457 * Returns a textual specification of @color in the hexadecimal form
458 * <literal>#rrggbbaa</literal>, where <literal>r</literal>,
459 * <literal>g</literal>, <literal>b</literal> and <literal>a</literal> are
460 * hex digits representing the red, green, blue and alpha components
463 * Return value: a newly-allocated text string
468 clutter_color_to_string (const ClutterColor *color)
470 g_return_val_if_fail (color != NULL, NULL);
472 return g_strdup_printf ("#%02x%02x%02x%02x",
480 * clutter_color_equal:
481 * @v1: a #ClutterColor
482 * @v2: a #ClutterColor
484 * Compares two #ClutterColor<!-- -->s and checks if they are the same.
486 * This function can be passed to g_hash_table_new() as the @key_equal_func
487 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
489 * Return value: %TRUE if the two colors are the same.
494 clutter_color_equal (gconstpointer v1,
497 const ClutterColor *a, *b;
499 g_return_val_if_fail (v1 != NULL, FALSE);
500 g_return_val_if_fail (v2 != NULL, FALSE);
508 return (a->red == b->red &&
509 a->green == b->green &&
510 a->blue == b->blue &&
511 a->alpha == b->alpha);
515 * clutter_color_hash:
516 * @v: a #ClutterColor
518 * Converts a #ClutterColor to a hash value.
520 * This function can be passed to g_hash_table_new() as the @hash_func
521 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
523 * Return value: a hash value corresponding to the color
528 clutter_color_hash (gconstpointer v)
530 return clutter_color_to_pixel ((const ClutterColor *) v);
534 * clutter_color_copy:
535 * @color: a #ClutterColor
537 * Makes a copy of the color structure. The result must be
538 * freed using clutter_color_free().
540 * Return value: an allocated copy of @color.
545 clutter_color_copy (const ClutterColor *color)
547 if (G_LIKELY (color != NULL))
548 return g_slice_dup (ClutterColor, color);
554 * clutter_color_free:
555 * @color: a #ClutterColor
557 * Frees a color structure created with clutter_color_copy().
562 clutter_color_free (ClutterColor *color)
564 if (G_LIKELY (color != NULL))
565 g_slice_free (ClutterColor, color);
570 * @red: red component of the color, between 0 and 255
571 * @green: green component of the color, between 0 and 255
572 * @blue: blue component of the color, between 0 and 255
573 * @alpha: alpha component of the color, between 0 and 255
575 * Creates a new #ClutterColor with the given values.
577 * Return value: the newly allocated color. Use clutter_color_free()
583 clutter_color_new (guint8 red,
590 color = g_slice_new (ClutterColor);
593 color->green = green;
595 color->alpha = alpha;
601 clutter_value_transform_color_string (const GValue *src,
604 gchar *string = clutter_color_to_string (src->data[0].v_pointer);
606 g_value_take_string (dest, string);
610 clutter_value_transform_string_color (const GValue *src,
613 ClutterColor color = { 0, };
615 clutter_color_from_string (&color, g_value_get_string (src));
617 clutter_value_set_color (dest, &color);
621 clutter_color_get_type (void)
623 static GType _clutter_color_type = 0;
625 if (G_UNLIKELY (_clutter_color_type == 0))
627 _clutter_color_type =
628 g_boxed_type_register_static (I_("ClutterColor"),
629 (GBoxedCopyFunc) clutter_color_copy,
630 (GBoxedFreeFunc) clutter_color_free);
632 g_value_register_transform_func (_clutter_color_type, G_TYPE_STRING,
633 clutter_value_transform_color_string);
634 g_value_register_transform_func (G_TYPE_STRING, _clutter_color_type,
635 clutter_value_transform_string_color);
638 return _clutter_color_type;
642 clutter_value_init_color (GValue *value)
644 value->data[0].v_pointer = NULL;
648 clutter_value_free_color (GValue *value)
650 if (!(value->data[1].v_uint & G_VALUE_NOCOPY_CONTENTS))
651 clutter_color_free (value->data[0].v_pointer);
655 clutter_value_copy_color (const GValue *src,
658 dest->data[0].v_pointer = clutter_color_copy (src->data[0].v_pointer);
662 clutter_value_peek_color (const GValue *value)
664 return value->data[0].v_pointer;
668 clutter_value_collect_color (GValue *value,
669 guint n_collect_values,
670 GTypeCValue *collect_values,
673 if (!collect_values[0].v_pointer)
674 value->data[0].v_pointer = NULL;
677 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
679 value->data[0].v_pointer = collect_values[0].v_pointer;
680 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
684 value->data[0].v_pointer =
685 clutter_color_copy (collect_values[0].v_pointer);
693 clutter_value_lcopy_color (const GValue *value,
694 guint n_collect_values,
695 GTypeCValue *collect_values,
698 ClutterColor **color_p = collect_values[0].v_pointer;
701 return g_strdup_printf ("value location for '%s' passed as NULL",
702 G_VALUE_TYPE_NAME (value));
704 if (!value->data[0].v_pointer)
708 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
709 *color_p = value->data[0].v_pointer;
711 *color_p = clutter_color_copy (value->data[0].v_pointer);
718 * clutter_value_set_color:
719 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
720 * @color: the color to set
722 * Sets @value to @color.
727 clutter_value_set_color (GValue *value,
728 const ClutterColor *color)
730 g_return_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value));
732 value->data[0].v_pointer = clutter_color_copy (color);
736 * clutter_value_get_color:
737 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
739 * Gets the #ClutterColor contained in @value.
741 * Return value: the colors inside the passed #GValue
745 G_CONST_RETURN ClutterColor *
746 clutter_value_get_color (const GValue *value)
748 g_return_val_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value), NULL);
750 return value->data[0].v_pointer;
754 param_color_init (GParamSpec *pspec)
756 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
758 cspec->default_value = NULL;
762 param_color_finalize (GParamSpec *pspec)
764 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
766 clutter_color_free (cspec->default_value);
770 param_color_set_default (GParamSpec *pspec,
773 value->data[0].v_pointer = CLUTTER_PARAM_SPEC_COLOR (pspec)->default_value;
774 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
778 param_color_values_cmp (GParamSpec *pspec,
779 const GValue *value1,
780 const GValue *value2)
782 guint32 color1, color2;
784 color1 = clutter_color_to_pixel (value1->data[0].v_pointer);
785 color2 = clutter_color_to_pixel (value2->data[0].v_pointer);
789 else if (color1 == color2)
795 static const GTypeValueTable _clutter_color_value_table = {
796 clutter_value_init_color,
797 clutter_value_free_color,
798 clutter_value_copy_color,
799 clutter_value_peek_color,
801 clutter_value_collect_color,
803 clutter_value_lcopy_color
807 clutter_param_color_get_type (void)
809 static GType pspec_type = 0;
811 if (G_UNLIKELY (pspec_type == 0))
813 const GParamSpecTypeInfo pspec_info = {
814 sizeof (ClutterParamSpecColor),
818 param_color_finalize,
819 param_color_set_default,
821 param_color_values_cmp,
824 pspec_type = g_param_type_register_static (I_("ClutterParamSpecColor"),
832 * clutter_param_spec_color:
833 * @name: name of the property
835 * @blurb: description (can be translatable)
836 * @default_value: default value
837 * @flags: flags for the param spec
839 * Creates a #GParamSpec for properties using #ClutterColor.
841 * Return value: the newly created #GParamSpec
846 clutter_param_spec_color (const gchar *name,
849 const ClutterColor *default_value,
852 ClutterParamSpecColor *cspec;
854 cspec = g_param_spec_internal (CLUTTER_TYPE_PARAM_COLOR,
855 name, nick, blurb, flags);
857 cspec->default_value = clutter_color_copy (default_value);
859 return G_PARAM_SPEC (cspec);