Ensure Okhsl and Okhsv return undefined hues for achromatic colors

Fixes #516
color-js · May 16, 2024 · af37eb5 · af37eb5
1 parent d49b1ae
commit af37eb5
Show file tree

Hide file tree

Showing 3 changed files with 14 additions and 4 deletions.
diff --git a/src/spaces/okhsl.js b/src/spaces/okhsl.js
@@ -458,6 +458,11 @@ function oklabToOkhsl (lab, lmsToRgb, okCoeff) {
 		}
 	}
 
+	if (Math.abs(s) < 1e-4 || l === 0.0 || Math.abs(1 - l) < 1e-7) {
+		h = NaN;
+		s = 0.0;
+	}
+
 	return [constrain(h * 360), s, l];
 }
 

diff --git a/src/spaces/okhsv.js b/src/spaces/okhsv.js
@@ -134,6 +134,11 @@ function oklabToOkhsv (lab, lmsToRgb, okCoeff) {
 		s = (s0 + tMax) * cv / ((tMax * s0) + tMax * k * cv);
 	}
 
+	if (Math.abs(s) < 1e-4 || v === 0.0) {
+		h = NaN;
+		s = 0.0;
+	}
+
 	return [constrain(h * 360), s, v];
 }
 

diff --git a/test/conversions.js b/test/conversions.js
@@ -969,7 +969,7 @@ const tests = {
 				{
 					name: "sRGB white to Okhsl",
 					args: "white",
-					expect: [180, 0.6519721306444567, 1.0000000000000002],
+					expect: [NaN, 0.0, 1.0000000000000002],
 				},
 				{
 					name: "sRGB red to Okhsl",
@@ -1004,7 +1004,7 @@ const tests = {
 				{
 					name: "sRGB black to Okhsl",
 					args: "black",
-					expect: [0.0, 0.0, 0.0],
+					expect: [NaN, 0.0, 0.0],
 				},
 			],
 		},
@@ -1017,7 +1017,7 @@ const tests = {
 				{
 					name: "sRGB white to Okhsv",
 					args: "white",
-					expect: [ 180, 1.3189507366749435e-15, 1.0000000000000007 ],
+					expect: [ NaN, 0.0, 1.0000000000000007 ],
 				},
 				{
 					name: "sRGB red to Okhsv",
@@ -1052,7 +1052,7 @@ const tests = {
 				{
 					name: "sRGB black to Okhsv",
 					args: "black",
-					expect: [0.0, 0.0, 0.0],
+					expect: [NaN, 0.0, 0.0],
 				},
 			],
 		},