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.
40 #include <pango/pango-attributes.h>
41 #include <gobject/gvaluecollector.h>
43 #include "clutter-main.h"
44 #include "clutter-color.h"
45 #include "clutter-private.h"
46 #include "clutter-debug.h"
52 * @result: (out): return location for the result
54 * Adds @a to @b and saves the resulting color inside @result.
56 * The alpha channel of @result is set as as the maximum value
57 * between the alpha channels of @a and @b.
60 clutter_color_add (const ClutterColor *a,
61 const ClutterColor *b,
64 g_return_if_fail (a != NULL);
65 g_return_if_fail (b != NULL);
66 g_return_if_fail (result != NULL);
68 result->red = CLAMP (a->red + b->red, 0, 255);
69 result->green = CLAMP (a->green + b->green, 0, 255);
70 result->blue = CLAMP (a->blue + b->blue, 0, 255);
72 result->alpha = MAX (a->alpha, b->alpha);
76 * clutter_color_subtract:
79 * @result: (out): return location for the result
81 * Subtracts @b from @a and saves the resulting color inside @result.
83 * This function assumes that the components of @a are greater than the
84 * components of @b; the result is, otherwise, undefined.
86 * The alpha channel of @result is set as the minimum value
87 * between the alpha channels of @a and @b.
90 clutter_color_subtract (const ClutterColor *a,
91 const ClutterColor *b,
94 g_return_if_fail (a != NULL);
95 g_return_if_fail (b != NULL);
96 g_return_if_fail (result != NULL);
98 result->red = CLAMP (a->red - b->red, 0, 255);
99 result->green = CLAMP (a->green - b->green, 0, 255);
100 result->blue = CLAMP (a->blue - b->blue, 0, 255);
102 result->alpha = MIN (a->alpha, b->alpha);
106 * clutter_color_lighten:
107 * @color: a #ClutterColor
108 * @result: (out): return location for the lighter color
110 * Lightens @color by a fixed amount, and saves the changed color
114 clutter_color_lighten (const ClutterColor *color,
115 ClutterColor *result)
117 clutter_color_shade (color, 1.3, result);
121 * clutter_color_darken:
122 * @color: a #ClutterColor
123 * @result: (out): return location for the darker color
125 * Darkens @color by a fixed amount, and saves the changed color
129 clutter_color_darken (const ClutterColor *color,
130 ClutterColor *result)
132 clutter_color_shade (color, 0.7, result);
136 * clutter_color_to_hls:
137 * @color: a #ClutterColor
138 * @hue: return location for the hue value or %NULL
139 * @luminance: return location for the luminance value or %NULL
140 * @saturation: return location for the saturation value or %NULL
142 * Converts @color to the HLS format.
144 * The @hue value is in the 0 .. 360 range. The @luminance and
145 * @saturation values are in the 0 .. 1 range.
148 clutter_color_to_hls (const ClutterColor *color,
153 float red, green, blue;
154 float min, max, delta;
157 g_return_if_fail (color != NULL);
159 red = color->red / 255.0;
160 green = color->green / 255.0;
161 blue = color->blue / 255.0;
195 s = (max - min) / (max + min);
197 s = (max - min) / (2.0 - max - min);
202 h = (green - blue) / delta;
203 else if (green == max)
204 h = 2.0 + (blue - red) / delta;
205 else if (blue == max)
206 h = 4.0 + (red - green) / delta;
225 * clutter_color_from_hls:
226 * @color: (out): return location for a #ClutterColor
227 * @hue: hue value, in the 0 .. 360 range
228 * @luminance: luminance value, in the 0 .. 1 range
229 * @saturation: saturation value, in the 0 .. 1 range
231 * Converts a color expressed in HLS (hue, luminance and saturation)
232 * values into a #ClutterColor.
235 clutter_color_from_hls (ClutterColor *color,
249 color->red = color->green = color->blue = 0;
255 color->red = color->green = color->blue = luminance;
259 if (luminance <= 0.5)
260 tmp2 = luminance * (1.0 + saturation);
262 tmp2 = luminance + saturation - (luminance * saturation);
264 tmp1 = 2.0 * luminance - tmp2;
266 tmp3[0] = hue + 1.0 / 3.0;
268 tmp3[2] = hue - 1.0 / 3.0;
270 for (i = 0; i < 3; i++)
277 if (6.0 * tmp3[i] < 1.0)
278 clr[i] = tmp1 + (tmp2 - tmp1) * tmp3[i] * 6.0;
279 else if (2.0 * tmp3[i] < 1.0)
281 else if (3.0 * tmp3[i] < 2.0)
282 clr[i] = (tmp1 + (tmp2 - tmp1) * ((2.0 / 3.0) - tmp3[i]) * 6.0);
287 color->red = clr[0] * 255.0;
288 color->green = clr[1] * 255.0;
289 color->blue = clr[2] * 255.0;
293 * clutter_color_shade:
294 * @color: a #ClutterColor
295 * @factor: the shade factor to apply
296 * @result: (out): return location for the shaded color
298 * Shades @color by @factor and saves the modified color into @result.
301 clutter_color_shade (const ClutterColor *color,
303 ClutterColor *result)
307 g_return_if_fail (color != NULL);
308 g_return_if_fail (result != NULL);
310 clutter_color_to_hls (color, &h, &l, &s);
324 clutter_color_from_hls (result, h, l, s);
326 result->alpha = color->alpha;
330 * clutter_color_to_pixel:
331 * @color: a #ClutterColor
333 * Converts @color into a packed 32 bit integer, containing
334 * all the four 8 bit channels used by #ClutterColor.
336 * Return value: a packed color
339 clutter_color_to_pixel (const ClutterColor *color)
341 g_return_val_if_fail (color != NULL, 0);
343 return (color->alpha |
350 * clutter_color_from_pixel:
351 * @color: (out): return location for a #ClutterColor
352 * @pixel: a 32 bit packed integer containing a color
354 * Converts @pixel from the packed representation of a four 8 bit channel
355 * color to a #ClutterColor.
358 clutter_color_from_pixel (ClutterColor *color,
361 g_return_if_fail (color != NULL);
363 color->red = pixel >> 24;
364 color->green = (pixel >> 16) & 0xff;
365 color->blue = (pixel >> 8) & 0xff;
366 color->alpha = pixel & 0xff;
370 * clutter_color_from_string:
371 * @color: (out): return location for a #ClutterColor
372 * @str: a string specifiying a color (named color or #RRGGBBAA)
374 * Parses a string definition of a color, filling the
375 * <structfield>red</structfield>, <structfield>green</structfield>,
376 * <structfield>blue</structfield> and <structfield>alpha</structfield>
377 * channels of @color. If alpha is not specified it will be set full opaque.
379 * The @color is not allocated.
381 * The color may be defined by any of the formats understood by
382 * pango_color_from_string(); these include literal color names, like
383 * <literal>Red</literal> or <literal>DarkSlateGray</literal>, or
384 * hexadecimal specifications like <literal>#3050b2</literal> or
385 * <literal>#333</literal>.
387 * Return value: %TRUE if parsing succeeded.
392 clutter_color_from_string (ClutterColor *color,
395 PangoColor pango_color = { 0, };
397 g_return_val_if_fail (color != NULL, FALSE);
398 g_return_val_if_fail (str != NULL, FALSE);
400 /* if the string contains a color encoded using the hexadecimal
401 * notations (#rrggbbaa or #rrggbb) we attempt a rough pass at
402 * parsing the color ourselves, as we need the alpha channel that
403 * Pango can't retrieve.
409 if (sscanf (str + 1, "%x", &result))
411 if (strlen (str) == 9)
414 color->red = (result >> 24) & 0xff;
415 color->green = (result >> 16) & 0xff;
416 color->blue = (result >> 8) & 0xff;
418 color->alpha = result & 0xff;
422 else if (strlen (str) == 7)
425 color->red = (result >> 16) & 0xff;
426 color->green = (result >> 8) & 0xff;
427 color->blue = result & 0xff;
435 /* XXX - should we return FALSE here? it's not like
436 * Pango is endowed with mystical parsing powers and
437 * will be able to do better than the code above.
438 * still, it doesn't hurt
442 /* Fall back to pango for named colors */
443 if (pango_color_parse (&pango_color, str))
445 color->red = pango_color.red;
446 color->green = pango_color.green;
447 color->blue = pango_color.blue;
458 * clutter_color_to_string:
459 * @color: a #ClutterColor
461 * Returns a textual specification of @color in the hexadecimal form
462 * <literal>#rrggbbaa</literal>, where <literal>r</literal>,
463 * <literal>g</literal>, <literal>b</literal> and <literal>a</literal> are
464 * hex digits representing the red, green, blue and alpha components
467 * Return value: a newly-allocated text string
472 clutter_color_to_string (const ClutterColor *color)
474 g_return_val_if_fail (color != NULL, NULL);
476 return g_strdup_printf ("#%02x%02x%02x%02x",
484 * clutter_color_equal:
485 * @v1: a #ClutterColor
486 * @v2: a #ClutterColor
488 * Compares two #ClutterColor<!-- -->s and checks if they are the same.
490 * This function can be passed to g_hash_table_new() as the @key_equal_func
491 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
493 * Return value: %TRUE if the two colors are the same.
498 clutter_color_equal (gconstpointer v1,
501 const ClutterColor *a, *b;
503 g_return_val_if_fail (v1 != NULL, FALSE);
504 g_return_val_if_fail (v2 != NULL, FALSE);
512 return (a->red == b->red &&
513 a->green == b->green &&
514 a->blue == b->blue &&
515 a->alpha == b->alpha);
519 * clutter_color_hash:
520 * @v: a #ClutterColor
522 * Converts a #ClutterColor to a hash value.
524 * This function can be passed to g_hash_table_new() as the @hash_func
525 * parameter, when using #ClutterColor<!-- -->s as keys in a #GHashTable.
527 * Return value: a hash value corresponding to the color
532 clutter_color_hash (gconstpointer v)
534 return clutter_color_to_pixel ((const ClutterColor *) v);
538 * clutter_color_copy:
539 * @color: a #ClutterColor
541 * Makes a copy of the color structure. The result must be
542 * freed using clutter_color_free().
544 * Return value: an allocated copy of @color.
549 clutter_color_copy (const ClutterColor *color)
551 if (G_LIKELY (color != NULL))
552 return g_slice_dup (ClutterColor, color);
558 * clutter_color_free:
559 * @color: a #ClutterColor
561 * Frees a color structure created with clutter_color_copy().
566 clutter_color_free (ClutterColor *color)
568 if (G_LIKELY (color != NULL))
569 g_slice_free (ClutterColor, color);
574 * @red: red component of the color, between 0 and 255
575 * @green: green component of the color, between 0 and 255
576 * @blue: blue component of the color, between 0 and 255
577 * @alpha: alpha component of the color, between 0 and 255
579 * Creates a new #ClutterColor with the given values.
581 * Return value: the newly allocated color. Use clutter_color_free()
587 clutter_color_new (guint8 red,
594 color = g_slice_new (ClutterColor);
597 color->green = green;
599 color->alpha = alpha;
605 clutter_value_transform_color_string (const GValue *src,
608 gchar *string = clutter_color_to_string (src->data[0].v_pointer);
610 g_value_take_string (dest, string);
614 clutter_value_transform_string_color (const GValue *src,
617 ClutterColor color = { 0, };
619 clutter_color_from_string (&color, g_value_get_string (src));
621 clutter_value_set_color (dest, &color);
625 clutter_color_get_type (void)
627 static GType _clutter_color_type = 0;
629 if (G_UNLIKELY (_clutter_color_type == 0))
631 _clutter_color_type =
632 g_boxed_type_register_static (I_("ClutterColor"),
633 (GBoxedCopyFunc) clutter_color_copy,
634 (GBoxedFreeFunc) clutter_color_free);
636 g_value_register_transform_func (_clutter_color_type, G_TYPE_STRING,
637 clutter_value_transform_color_string);
638 g_value_register_transform_func (G_TYPE_STRING, _clutter_color_type,
639 clutter_value_transform_string_color);
642 return _clutter_color_type;
646 clutter_value_init_color (GValue *value)
648 value->data[0].v_pointer = NULL;
652 clutter_value_free_color (GValue *value)
654 if (!(value->data[1].v_uint & G_VALUE_NOCOPY_CONTENTS))
655 clutter_color_free (value->data[0].v_pointer);
659 clutter_value_copy_color (const GValue *src,
662 dest->data[0].v_pointer = clutter_color_copy (src->data[0].v_pointer);
666 clutter_value_peek_color (const GValue *value)
668 return value->data[0].v_pointer;
672 clutter_value_collect_color (GValue *value,
673 guint n_collect_values,
674 GTypeCValue *collect_values,
677 if (!collect_values[0].v_pointer)
678 value->data[0].v_pointer = NULL;
681 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
683 value->data[0].v_pointer = collect_values[0].v_pointer;
684 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
688 value->data[0].v_pointer =
689 clutter_color_copy (collect_values[0].v_pointer);
697 clutter_value_lcopy_color (const GValue *value,
698 guint n_collect_values,
699 GTypeCValue *collect_values,
702 ClutterColor **color_p = collect_values[0].v_pointer;
705 return g_strdup_printf ("value location for `%s' passed as NULL",
706 G_VALUE_TYPE_NAME (value));
708 if (!value->data[0].v_pointer)
712 if (collect_flags & G_VALUE_NOCOPY_CONTENTS)
713 *color_p = value->data[0].v_pointer;
715 *color_p = clutter_color_copy (value->data[0].v_pointer);
722 * clutter_value_set_color:
723 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
724 * @color: the color to set
726 * Sets @value to @color.
731 clutter_value_set_color (GValue *value,
732 const ClutterColor *color)
734 g_return_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value));
736 value->data[0].v_pointer = clutter_color_copy (color);
740 * clutter_value_get_color:
741 * @value: a #GValue initialized to #CLUTTER_TYPE_COLOR
743 * Gets the #ClutterColor contained in @value.
745 * Return value: the colors inside the passed #GValue
749 G_CONST_RETURN ClutterColor *
750 clutter_value_get_color (const GValue *value)
752 g_return_val_if_fail (CLUTTER_VALUE_HOLDS_COLOR (value), NULL);
754 return value->data[0].v_pointer;
758 param_color_init (GParamSpec *pspec)
760 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
762 cspec->default_value = NULL;
766 param_color_finalize (GParamSpec *pspec)
768 ClutterParamSpecColor *cspec = CLUTTER_PARAM_SPEC_COLOR (pspec);
770 clutter_color_free (cspec->default_value);
774 param_color_set_default (GParamSpec *pspec,
777 value->data[0].v_pointer = CLUTTER_PARAM_SPEC_COLOR (pspec)->default_value;
778 value->data[1].v_uint = G_VALUE_NOCOPY_CONTENTS;
782 param_color_values_cmp (GParamSpec *pspec,
783 const GValue *value1,
784 const GValue *value2)
786 guint32 color1, color2;
788 color1 = clutter_color_to_pixel (value1->data[0].v_pointer);
789 color2 = clutter_color_to_pixel (value2->data[0].v_pointer);
793 else if (color1 == color2)
799 static const GTypeValueTable _clutter_color_value_table = {
800 clutter_value_init_color,
801 clutter_value_free_color,
802 clutter_value_copy_color,
803 clutter_value_peek_color,
805 clutter_value_collect_color,
807 clutter_value_lcopy_color
811 clutter_param_color_get_type (void)
813 static GType pspec_type = 0;
815 if (G_UNLIKELY (pspec_type == 0))
817 const GParamSpecTypeInfo pspec_info = {
818 sizeof (ClutterParamSpecColor),
822 param_color_finalize,
823 param_color_set_default,
825 param_color_values_cmp,
828 pspec_type = g_param_type_register_static (I_("ClutterParamSpecColor"),
836 * clutter_param_spec_color:
837 * @name: name of the property
839 * @blurb: description (can be translatable)
840 * @default_value: default value
841 * @flags: flags for the param spec
843 * Creates a #GParamSpec for properties using #ClutterColor.
845 * Return value: the newly created #GParamSpec
850 clutter_param_spec_color (const gchar *name,
853 const ClutterColor *default_value,
856 ClutterParamSpecColor *cspec;
858 cspec = g_param_spec_internal (CLUTTER_TYPE_PARAM_COLOR,
859 name, nick, blurb, flags);
861 cspec->default_value = clutter_color_copy (default_value);
863 return G_PARAM_SPEC (cspec);