avoid gamut mapping

kainino0x · kainino0x · commit 7cf11da5f515 · 2024-03-19T18:37:27.000-07:00
diff --git a/spec/index.bs b/spec/index.bs
@@ -2161,14 +2161,17 @@ An [=out-of-range premultiplied RGBA value=] is one for which the unpremultiplie
 of the same color would be outside of the range of the format.
 
 <div class=example>
-    For example, the unpremultiplied sRGB RGBA value `[1.04, 0, 0, 0.5]` and the
+    For example, on a display with a color space of exactly Display P3,
+    the unpremultiplied sRGB RGBA value `[1.04, 0, 0, 0.5]` and the
     premultiplied sRGB RGBA value `[0.52, 0, 0, 0.5]` both represent the
     CSS color <code><a funcdef>color</a>(srgb 1.04 0 0 / 0.5)</code>, which is equivalent to the
     in-gamut Display P3 color <code><a funcdef>color</a>(display-p3 0.95 0.21 0.15 / 0.5)</code>.
 
     When represented in a {{PredefinedColorSpace/"srgb"}} {{GPUTextureFormat/"rgba8unorm"}} canvas,
     both values are out-of-range for the purposes of this definition,
     even though the premultiplied value is representable.
+
+    (The colors in this example are in the gamut of the display to avoid any gamut mapping.)
 </div>
 
 When a canvas containing such a value is
@@ -2212,6 +2215,8 @@ displayed *on screen*, the visible result for the entire canvas is undefined.
         then sent to the display buffer resulting in the appearance of
         <code><a funcdef>color</a>(display-p3 0.92 0.2 0.14 / 0.5)</code>.
     - Value displayed by some other process.
+
+    (The colors in this example are in the gamut of the display to avoid any gamut mapping.)
 </div>
 
 Note:
