Color Handling
***********************************************************************/
-/* Parse hex color component at S ending right before E.
- Set *DST to the value normalized so that the maximum for the
- number of digits given becomes 65535, and return true on success,
- false otherwise. */
+/* Parse hex color component specification that starts at S and ends
+ right before E. Set *DST to the parsed value normalized so that
+ the maximum value for the number of hex digits given becomes 65535,
+ and return true on success, false otherwise. */
static bool
parse_hex_color_comp (const char *s, const char *e, unsigned short *dst)
{
return true;
}
-/* Parse floating-point color component at S ending right before E.
- Return the number if in the range [0,1]; otherwise -1. */
+/* Parse floating-point color component specification that starts at S
+ and ends right before E. Return the parsed number if in the range
+ [0,1]; otherwise return -1. */
static double
parse_float_color_comp (const char *s, const char *e)
{
return (end == e && x >= 0 && x <= 1) ? x : -1;
}
-/* Parse S as a numeric color specification and set *R, *G and *B.
+/* Parse SPEC as a numeric color specification and set *R, *G and *B.
Return true on success, false on failure.
- Recognized formats:
- "#RGB", with R, G and B hex strings of equal length, 1-4 digits each
- "rgb:R/G/B", with R, G and B hex strings, 1-4 digits each
- "rgbi:R/G/B", with R, G and B numbers in [0,1]
+ Recognized formats of SPEC:
- The result is normalized to a maximum value of 65535 per component. */
+ "#RGB", with R, G and B hex strings of equal length, 1-4 digits each.
+ "rgb:R/G/B", with R, G and B hex strings, 1-4 digits each.
+ "rgbi:R/G/B", with R, G and B numbers in [0,1].
+
+ If the function succeeds, it assigns to each of the components *R,
+ *G, and *B a value normalized to be in the [0, 65535] range. If
+ the function fails, some or all of the components remain unassigned. */
bool
-parse_color_spec (const char *s,
+parse_color_spec (const char *spec,
unsigned short *r, unsigned short *g, unsigned short *b)
{
- int len = strlen (s);
- if (s[0] == '#')
+ int len = strlen (spec);
+ if (spec[0] == '#')
{
if ((len - 1) % 3 == 0)
{
int n = (len - 1) / 3;
- return ( parse_hex_color_comp (s + 1 + 0 * n, s + 1 + 1 * n, r)
- && parse_hex_color_comp (s + 1 + 1 * n, s + 1 + 2 * n, g)
- && parse_hex_color_comp (s + 1 + 2 * n, s + 1 + 3 * n, b));
+ return ( parse_hex_color_comp (spec + 1 + 0 * n,
+ spec + 1 + 1 * n, r)
+ && parse_hex_color_comp (spec + 1 + 1 * n,
+ spec + 1 + 2 * n, g)
+ && parse_hex_color_comp (spec + 1 + 2 * n,
+ spec + 1 + 3 * n, b));
}
}
- else if (strncmp (s, "rgb:", 4) == 0)
+ else if (strncmp (spec, "rgb:", 4) == 0)
{
char *sep1, *sep2;
- return ((sep1 = strchr (s + 4, '/')) != NULL
+ return ((sep1 = strchr (spec + 4, '/')) != NULL
&& (sep2 = strchr (sep1 + 1, '/')) != NULL
- && parse_hex_color_comp (s + 4, sep1, r)
+ && parse_hex_color_comp (spec + 4, sep1, r)
&& parse_hex_color_comp (sep1 + 1, sep2, g)
- && parse_hex_color_comp (sep2 + 1, s + len, b));
+ && parse_hex_color_comp (sep2 + 1, spec + len, b));
}
- else if (strncmp (s, "rgbi:", 5) == 0)
+ else if (strncmp (spec, "rgbi:", 5) == 0)
{
char *sep1, *sep2;
double red, green, blue;
- if ((sep1 = strchr (s + 5, '/')) != NULL
+ if ((sep1 = strchr (spec + 5, '/')) != NULL
&& (sep2 = strchr (sep1 + 1, '/')) != NULL
- && (red = parse_float_color_comp (s + 5, sep1)) >= 0
+ && (red = parse_float_color_comp (spec + 5, sep1)) >= 0
&& (green = parse_float_color_comp (sep1 + 1, sep2)) >= 0
- && (blue = parse_float_color_comp (sep2 + 1, s + len)) >= 0)
+ && (blue = parse_float_color_comp (sep2 + 1, spec + len)) >= 0)
{
*r = lrint (red * 65535);
*g = lrint (green * 65535);
return false;
}
-DEFUN ("internal-color-values-from-color-spec",
- Finternal_color_values_from_color_spec,
- Sinternal_color_values_from_color_spec,
+DEFUN ("color-values-from-color-spec",
+ Fcolor_values_from_color_spec,
+ Scolor_values_from_color_spec,
1, 1, 0,
- doc: /* Parse STRING as a numeric color and return (RED GREEN BLUE).
-Recognised formats for STRING are:
+ doc: /* Parse color SPEC as a numeric color and return (RED GREEN BLUE).
+This function recognises the following formats for SPEC:
+
+ #RGB, where R, G and B are hex numbers of equal length, 1-4 digits each.
+ rgb:R/G/B, where R, G, and B are hex numbers, 1-4 digits each.
+ rgbi:R/G/B, where R, G and B are floating-point numbers in [0,1].
- #RGB, where R, G and B are hex numbers of equal length, 1-4 digits each
- rgb:R/G/B, where R, G, and B are hex numbers, 1-4 digits each
- rgbi:R/G/B, where R, G and B are floating-point numbers in [0,1]
+If SPEC is not in one of the above forms, return nil.
-The result is normalized to a maximum value of 65535 per component,
-forming a list of three integers in [0,65535].
-If STRING is not in one of the above forms, return nil. */)
- (Lisp_Object string)
+Each of the 3 integer members of the resulting list, RED, GREEN, and BLUE,
+is normalized to have its value in [0,65535]. */)
+ (Lisp_Object spec)
{
- CHECK_STRING (string);
+ CHECK_STRING (spec);
unsigned short r, g, b;
- return (parse_color_spec (SSDATA (string), &r, &g, &b)
+ return (parse_color_spec (SSDATA (spec), &r, &g, &b)
? list3i (r, g, b)
: Qnil);
}
defsubr (&Sinternal_face_x_get_resource);
defsubr (&Sx_family_fonts);
#endif
- defsubr (&Sinternal_color_values_from_color_spec);
+ defsubr (&Scolor_values_from_color_spec);
}
(color-distance "#ffffff" "#222222"))))
(ert-deftest xfaces-internal-color-values-from-color-spec ()
- (should (equal (internal-color-values-from-color-spec "#f05")
+ (should (equal (color-values-from-color-spec "#f05")
'(#xffff #x0000 #x5555)))
- (should (equal (internal-color-values-from-color-spec "#1fb0C5")
+ (should (equal (color-values-from-color-spec "#1fb0C5")
'(#x1f1f #xb0b0 #xc5c5)))
- (should (equal (internal-color-values-from-color-spec "#1f8b0AC5e")
+ (should (equal (color-values-from-color-spec "#1f8b0AC5e")
'(#x1f81 #xb0aa #xc5eb)))
- (should (equal (internal-color-values-from-color-spec "#1f83b0ADC5e2")
+ (should (equal (color-values-from-color-spec "#1f83b0ADC5e2")
'(#x1f83 #xb0ad #xc5e2)))
- (should (equal (internal-color-values-from-color-spec "#1f83b0ADC5e2g") nil))
- (should (equal (internal-color-values-from-color-spec "#1f83b0ADC5e20") nil))
- (should (equal (internal-color-values-from-color-spec "#12345") nil))
- (should (equal (internal-color-values-from-color-spec "rgb:f/23/28a")
+ (should (equal (color-values-from-color-spec "#1f83b0ADC5e2g") nil))
+ (should (equal (color-values-from-color-spec "#1f83b0ADC5e20") nil))
+ (should (equal (color-values-from-color-spec "#12345") nil))
+ (should (equal (color-values-from-color-spec "rgb:f/23/28a")
'(#xffff #x2323 #x28a2)))
- (should (equal (internal-color-values-from-color-spec "rgb:1234/5678/09ab")
+ (should (equal (color-values-from-color-spec "rgb:1234/5678/09ab")
'(#x1234 #x5678 #x09ab)))
- (should (equal (internal-color-values-from-color-spec "rgb:0//0") nil))
- (should (equal (internal-color-values-from-color-spec "rgbi:0/0.5/0.1")
+ (should (equal (color-values-from-color-spec "rgb:0//0") nil))
+ (should (equal (color-values-from-color-spec "rgbi:0/0.5/0.1")
'(0 32768 6554)))
- (should (equal (internal-color-values-from-color-spec "rgbi:1e-3/1.0e-2/1e0")
+ (should (equal (color-values-from-color-spec "rgbi:1e-3/1.0e-2/1e0")
'(66 655 65535)))
- (should (equal (internal-color-values-from-color-spec "rgbi:0/0.5/10") nil)))
+ (should (equal (color-values-from-color-spec "rgbi:0/0.5/10") nil)))
(provide 'xfaces-tests)