← All changes | app/Services/Theme/ColorMath.php +74 -0 1.6.5 → 1.6.6 View file →

		@@ -201,8 +201,82 @@
201	201	return self::contrast($background, $light) >= self::contrast($background, $dark) ? $light : $dark;
202	202	}
203	203
204	204	/**
	205	+ * A text colour that reads on a background (WCAG 4.5:1) wherever one can.
	206	+ *
	207	+ * readableOn()'s usual pair is kept whenever it reads, so every partner it
	208	+ * already made readable is unchanged. On a mid-tone background neither
	209	+ * half of that pair reaches 4.5:1 (#809400 peaks at 4.30:1 with #1f2937);
	210	+ * pure black or white — whichever reads better — goes further, and is
	211	+ * taken only when it does.
	212	+ *
	213	+ * @param string $background
	214	+ * @return string
	215	+ */
	216	+ public static function readableText($background): string
	217	+ {
	218	+ $picked = self::readableOn($background);
	219	+ $pickedContrast = self::contrast($background, $picked);
	220	+
	221	+ if ($pickedContrast >= 4.5) {
	222	+ return $picked;
	223	+ }
	224	+
	225	+ $extreme = self::contrast($background, '#ffffff') >= self::contrast($background, '#000000')
	226	+ ? '#ffffff'
	227	+ : '#000000';
	228	+
	229	+ return self::contrast($background, $extreme) > $pickedContrast ? $extreme : $picked;
	230	+ }
	231	+
	232	+ /**
	233	+ * Mix text into a surface, keeping as little of the text as still reads.
	234	+ *
	235	+ * Starts at $percent of the text and moves toward it in small steps until
	236	+ * the mix reaches $minimum contrast on the surface — a mix that already
	237	+ * reads is returned unchanged. Text that does not read on the surface
	238	+ * itself comes back as the text: nothing between the two reads better.
	239	+ *
	240	+ * @param string $text
	241	+ * @param string $surface
	242	+ * @param int $percent Starting share of the text, 0-100.
	243	+ * @param float $minimum
	244	+ * @return string Hex, or '' when either colour is unreadable.
	245	+ */
	246	+ public static function readableMix($text, $surface, int $percent, float $minimum = 4.5): string
	247	+ {
	248	+ if (!self::parse($text) || !self::parse($surface)) {
	249	+ return '';
	250	+ }
	251	+
	252	+ for ($share = max(0, $percent); $share < 100; $share += 2) {
	253	+ $mixed = self::mix($text, $surface, $share);
	254	+
	255	+ if (self::contrast($surface, $mixed) >= $minimum) {
	256	+ return $mixed;
	257	+ }
	258	+ }
	259	+
	260	+ return self::hex($text);
	261	+ }
	262	+
	263	+ /**
	264	+ * Move a colour away from itself — lighter when it is dark, darker when it
	265	+ * is light. How a hover is derived from a button that states none.
	266	+ *
	267	+ * @param string $color
	268	+ * @param int $percent
	269	+ * @return string
	270	+ */
	271	+ public static function shiftFromItself($color, int $percent = 12): string
	272	+ {
	273	+ return self::isDark($color)
	274	+ ? self::lighten($color, $percent)
	275	+ : self::darken($color, $percent);
	276	+ }
	277	+
	278	+ /**
205	279	* Nudge a colour toward white.
206	280	*
207	281	* @param string $color
208	282	* @param int $percent