From f913c35904798b929f045ba5f2b386e888bcdc5f Mon Sep 17 00:00:00 2001
From: Christopher Serr <christopher.serr@gmail.com>
Date: Fri, 9 Aug 2019 11:10:29 +0200
Subject: [PATCH] Fix no_std build failure

{f32|f64}::round() does not exist with just core, so libm's
implementation is used instead when the `std` feature is not activated.
---
 palette/src/float.rs |  8 ++++++++
 palette/src/lib.rs   | 12 ++++++------
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/palette/src/float.rs b/palette/src/float.rs
index 35c1356a6..6976b9565 100644
--- a/palette/src/float.rs
+++ b/palette/src/float.rs
@@ -57,6 +57,8 @@ mod no_std_float_trait {
         /// `y.atan2(x)` computes the inverse tangent of `y / x`, in the
         /// corresponding quadrant
         fn atan2(self, other: Self) -> Self;
+        /// `x.round()` returns the nearest integer to a number. Round half-way cases away from 0.0.
+        fn round(self) -> Self;
     }
 
     impl Float for f32 {
@@ -78,6 +80,9 @@ mod no_std_float_trait {
         fn atan2(self, other: f32) -> f32 {
             F32Ext::atan2(self, other)
         }
+        fn round(self) -> f32 {
+            F32Ext::round(self)
+        }
     }
 
     impl Float for f64 {
@@ -99,5 +104,8 @@ mod no_std_float_trait {
         fn atan2(self, other: f64) -> f64 {
             F64Ext::atan2(self, other)
         }
+        fn round(self) -> f64 {
+            F64Ext::round(self)
+        }
     }
 }
diff --git a/palette/src/lib.rs b/palette/src/lib.rs
index 45c508c89..757a2f989 100644
--- a/palette/src/lib.rs
+++ b/palette/src/lib.rs
@@ -550,7 +550,7 @@ impl Component for f32 {
         let scaled = *self * cast::<f32, _>(T::max_intensity());
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }
@@ -568,7 +568,7 @@ impl Component for f64 {
         let scaled = *self * cast::<f64, _>(T::max_intensity());
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }
@@ -587,7 +587,7 @@ impl Component for u8 {
             * (cast::<f64, _>(*self) / cast::<f64, _>(Self::max_intensity()));
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }
@@ -606,7 +606,7 @@ impl Component for u16 {
             * (cast::<f64, _>(*self) / cast::<f64, _>(Self::max_intensity()));
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }
@@ -625,7 +625,7 @@ impl Component for u32 {
             * (cast::<f64, _>(*self) / cast::<f64, _>(Self::max_intensity()));
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }
@@ -644,7 +644,7 @@ impl Component for u64 {
             * (cast::<f64, _>(*self) / cast::<f64, _>(Self::max_intensity()));
 
         if T::LIMITED {
-            cast(clamp(scaled.round(), 0.0, cast(T::max_intensity())))
+            cast(clamp(Float::round(scaled), 0.0, cast(T::max_intensity())))
         } else {
             cast(scaled)
         }