colors.hsv: adding complimentary-color.

diff --git a/basis/colors/hsv/hsv.factor b/basis/colors/hsv/hsv.factor
index d604c9d9143f6f9807a3657871dbe284caee9586..65e51be475837d846752b4d45b3cc86ae5eaffbe 100644 (file)
--- a/basis/colors/hsv/hsv.factor
+++ b/basis/colors/hsv/hsv.factor
@@ -55,3 +55,12 @@ M: hsva >rgba ( hsva -- rgba )
             { [ b x = r z > and ] [ 5 x r - x z - / - ] }
         } cond 6 / 360 * x z - x / x a <hsva>
     ] if ;
+
+: complimentary-color ( color -- color' )
+    dup hsva? [ >rgba rgba>hsva ] unless
+    {
+        [ hue>> 180 + 360 mod ]
+        [ saturation>> ]
+        [ value>> ]
+        [ alpha>> ]
+    } cleave <hsva> ;