Round float before converting to u8

Else you get 0.999999 == 254
Beinsezii · Jun 28, 2024 · 5099477 · 5099477
1 parent f6adbe3
commit 5099477
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diff --git a/src/lib.rs b/src/lib.rs
@@ -903,7 +903,7 @@ pub fn srgb_to_irgb<const N: usize>(pixel: [f32; N]) -> [u8; N]
 where
     Channels<N>: ValidChannels,
 {
-    pixel.map(|c| ((c * 255.0).max(0.0).min(255.0) as u8))
+    pixel.map(|c| ((c * 255.0).round().max(0.0).min(255.0) as u8))
 }
 
 /// Create a hexadecimal string from integer RGB.

diff --git a/src/tests.rs b/src/tests.rs
@@ -192,6 +192,11 @@ fn irgb_convert() {
     let mut srgba = irgb_to_srgb::<f32, 4>(IRGBA);
     srgba.iter_mut().for_each(|c| *c = (*c * 100.0).round() / 100.0);
     assert_eq!([0.2, 0.35, 0.95, 0.35], srgba);
+
+    // 254.4 / 255.0 ≈ 0.9970 // round up
+    // 254.6 / 255.0 ≈ 0.9984 // round down
+    let close_call = [0.9970, 0.9984, 0.999999];
+    assert_eq!(srgb_to_irgb(close_call), [254, 255, 255]);
 }
 
 #[test]