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, see <http://www.gnu.org/licenses/>.
25 * SECTION:clutter-color
26 * @short_description: Color management and manipulation.
28 * #ClutterColor is a simple type for representing colors in Clutter.
30 * A #ClutterColor is expressed as a 4-tuple of values ranging from
31 * zero to 255, one for each color channel plus one for the alpha.
33 * 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 = floorf (clr[0] * 255.0 + 0.5);
286 color->green = floorf (clr[1] * 255.0 + 0.5);
287 color->blue = floorf (clr[2] * 255.0 + 0.5);
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 gsize length = strlen (str);
413 case 9: /* rrggbbaa */
414 color->red = (result >> 24) & 0xff;
415 color->green = (result >> 16) & 0xff;
416 color->blue = (result >> 8) & 0xff;
418 color->alpha = result & 0xff;
422 case 7: /* #rrggbb */
423 color->red = (result >> 16) & 0xff;
424 color->green = (result >> 8) & 0xff;
425 color->blue = result & 0xff;
432 color->red = ((result >> 12) & 0xf);
433 color->green = ((result >> 8) & 0xf);
434 color->blue = ((result >> 4) & 0xf);
435 color->alpha = result & 0xf;
437 color->red = (color->red << 4) | color->red;
438 color->green = (color->green << 4) | color->green;
439 color->blue = (color->blue << 4) | color->blue;
440 color->alpha = (color->alpha << 4) | color->alpha;
445 color->red = ((result >> 8) & 0xf);
446 color->green = ((result >> 4) & 0xf);
447 color->blue = result & 0xf;
449 color->red = (color->red << 4) | color->red;
450 color->green = (color->green << 4) | color->green;
451 color->blue = (color->blue << 4) | color->blue;
458 /* pass through to Pango */
464 /* Fall back to pango for named colors */
465 if (pango_color_parse (&pango_color, str))
467 color->red = pango_color.red;
468 color->green = pango_color.green;
469 color->blue = pango_color.blue;
480 * clutter_color_to_string:
481 * @color: a #ClutterColor
483 * Returns a textual specification of @color in the hexadecimal form
484 * <literal>#rrggbbaa</literal>, where <literal>r</literal>,
485 * <literal>g</literal>, <literal>b</literal> and <literal>a</literal> are
486 * hex digits representing the red, green, blue and alpha components
489 * Return value: a newly-allocated text string
494 clutter_color_to_string (const ClutterColor *color)
496 g_return_val_if_fail (color != NULL, NULL);
498 return g_strdup_printf ("#%02x%02x%02x%02x",
506 * clutter_color_equal:
507 * @v1: a #ClutterColor
508 * @v2: a #ClutterColor
510 * Compares two #ClutterColor<!-- -->s and checks if they are the same.
512 * This function can be passed to g_hash_table_new() as the @key_equal_func
513 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
515 * Return value: %TRUE if the two colors are the same.
520 clutter_color_equal (gconstpointer v1,
523 const ClutterColor *a, *b;
525 g_return_val_if_fail (v1 != NULL, FALSE);
526 g_return_val_if_fail (v2 != NULL, FALSE);
534 return (a->red == b->red &&
535 a->green == b->green &&
536 a->blue == b->blue &&
537 a->alpha == b->alpha);
541 * clutter_color_hash:
542 * @v: a #ClutterColor
544 * Converts a #ClutterColor to a hash value.
546 * This function can be passed to g_hash_table_new() as the @hash_func
547 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
549 * Return value: a hash value corresponding to the color
554 clutter_color_hash (gconstpointer v)
556 return clutter_color_to_pixel ((const ClutterColor *) v);
560 * clutter_color_copy:
561 * @color: a #ClutterColor
563 * Makes a copy of the color structure. The result must be
564 * freed using clutter_color_free().
566 * Return value: an allocated copy of @color.
571 clutter_color_copy (const ClutterColor *color)
573 if (G_LIKELY (color != NULL))
574 return g_slice_dup (ClutterColor, color);
580 * clutter_color_free:
581 * @color: a #ClutterColor
583 * Frees a color structure created with clutter_color_copy().
588 clutter_color_free (ClutterColor *color)
590 if (G_LIKELY (color != NULL))
591 g_slice_free (ClutterColor, color);
596 * @red: red component of the color, between 0 and 255
597 * @green: green component of the color, between 0 and 255
598 * @blue: blue component of the color, between 0 and 255
599 * @alpha: alpha component of the color, between 0 and 255
601 * Creates a new #ClutterColor with the given values.
603 * Return value: the newly allocated color. Use clutter_color_free()
609 clutter_color_new (guint8 red,
616 color = g_slice_new (ClutterColor);
619 color->green = green;
621 color->alpha = alpha;
627 clutter_value_transform_color_string (const GValue *src,
630 gchar *string = clutter_color_to_string (src->data[0].v_pointer);
632 g_value_take_string (dest, string);
636 clutter_value_transform_string_color (const GValue *src,
639 ClutterColor color = { 0, };
641 clutter_color_from_string (&color, g_value_get_string (src));
643 clutter_value_set_color (dest, &color);
647 clutter_color_get_type (void)
649 static GType _clutter_color_type = 0;
651 if (G_UNLIKELY (_clutter_color_type == 0))
653 _clutter_color_type =
654 g_boxed_type_register_static (I_("ClutterColor"),
655 (GBoxedCopyFunc) clutter_color_copy,
656 (GBoxedFreeFunc) clutter_color_free);
658 g_value_register_transform_func (_clutter_color_type, G_TYPE_STRING,
659 clutter_value_transform_color_string);
660 g_value_register_transform_func (G_TYPE_STRING, _clutter_color_type,
661 clutter_value_transform_string_color);
664 return _clutter_color_type;
668 clutter_value_init_color (GValue *value)
670 value->data[0].v_pointer = NULL;
674 clutter_value_free_color (GValue *value)
676 if (!(value->data[1].v_uint & G_VALUE_NOCOPY_CONTENTS))
677 clutter_color_free (value->data[0].v_pointer);
681 clutter_value_copy_color (const GValue *src,
684 dest->data[0].v_pointer = clutter_color_copy (src->data[0].v_pointer);
688 clutter_value_peek_color (const GValue *value)
690 return value->data[0].v_pointer;
694 clutter_value_collect_color (GValue *value,
695 guint n_collect_values,
696 GTypeCValue *collect_values,
699 if (!collect_values[0].v_pointer)
700 value->data[0].v_pointer = NULL;
703 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
705 value->data[0].v_pointer = collect_values[0].v_pointer;
706 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
710 value->data[0].v_pointer =
711 clutter_color_copy (collect_values[0].v_pointer);
719 clutter_value_lcopy_color (const GValue *value,
720 guint n_collect_values,
721 GTypeCValue *collect_values,
724 ClutterColor **color_p = collect_values[0].v_pointer;
727 return g_strdup_printf ("value location for '%s' passed as NULL",
728 G_VALUE_TYPE_NAME (value));
730 if (!value->data[0].v_pointer)
734 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
735 *color_p = value->data[0].v_pointer;
737 *color_p = clutter_color_copy (value->data[0].v_pointer);
744 * clutter_value_set_color:
745 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
746 * @color: the color to set
748 * Sets @value to @color.
753 clutter_value_set_color (GValue *value,
754 const ClutterColor *color)
756 g_return_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value));
758 value->data[0].v_pointer = clutter_color_copy (color);
762 * clutter_value_get_color:
763 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
765 * Gets the #ClutterColor contained in @value.
767 * Return value: the colors inside the passed #GValue
771 G_CONST_RETURN ClutterColor *
772 clutter_value_get_color (const GValue *value)
774 g_return_val_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value), NULL);
776 return value->data[0].v_pointer;
780 param_color_init (GParamSpec *pspec)
782 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
784 cspec->default_value = NULL;
788 param_color_finalize (GParamSpec *pspec)
790 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
792 clutter_color_free (cspec->default_value);
796 param_color_set_default (GParamSpec *pspec,
799 value->data[0].v_pointer = CLUTTER_PARAM_SPEC_COLOR (pspec)->default_value;
800 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
804 param_color_values_cmp (GParamSpec *pspec,
805 const GValue *value1,
806 const GValue *value2)
808 guint32 color1, color2;
810 color1 = clutter_color_to_pixel (value1->data[0].v_pointer);
811 color2 = clutter_color_to_pixel (value2->data[0].v_pointer);
815 else if (color1 == color2)
821 static const GTypeValueTable _clutter_color_value_table = {
822 clutter_value_init_color,
823 clutter_value_free_color,
824 clutter_value_copy_color,
825 clutter_value_peek_color,
827 clutter_value_collect_color,
829 clutter_value_lcopy_color
833 clutter_param_color_get_type (void)
835 static GType pspec_type = 0;
837 if (G_UNLIKELY (pspec_type == 0))
839 const GParamSpecTypeInfo pspec_info = {
840 sizeof (ClutterParamSpecColor),
844 param_color_finalize,
845 param_color_set_default,
847 param_color_values_cmp,
850 pspec_type = g_param_type_register_static (I_("ClutterParamSpecColor"),
858 * clutter_param_spec_color:
859 * @name: name of the property
861 * @blurb: description (can be translatable)
862 * @default_value: default value
863 * @flags: flags for the param spec
865 * Creates a #GParamSpec for properties using #ClutterColor.
867 * Return value: the newly created #GParamSpec
872 clutter_param_spec_color (const gchar *name,
875 const ClutterColor *default_value,
878 ClutterParamSpecColor *cspec;
880 cspec = g_param_spec_internal (CLUTTER_TYPE_PARAM_COLOR,
881 name, nick, blurb, flags);
883 cspec->default_value = clutter_color_copy (default_value);
885 return G_PARAM_SPEC (cspec);