From 2162ffff42c7cfda22543c0a4e6648f52a61a433 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Wed, 10 Jun 2020 16:22:31 +0200
Subject: [PATCH] [slider] round so what you see is what you get

---
 egui/src/math.rs           | 7 +++++++
 egui/src/widgets/slider.rs | 4 +---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/egui/src/math.rs b/egui/src/math.rs
index f6a25c23..ebc7090b 100644
--- a/egui/src/math.rs
+++ b/egui/src/math.rs
@@ -591,3 +591,10 @@ pub fn ease_in_ease_out(t: f32) -> f32 {
 }
 
 pub const TAU: f32 = 2.0 * std::f32::consts::PI;
+
+pub fn round_to_precision(value: f32, precision: usize) -> f32 {
+    // This is a stupid way of doing this, but stupid works.
+    format!("{:.*}", precision, value)
+        .parse()
+        .unwrap_or_else(|_| value)
+}
diff --git a/egui/src/widgets/slider.rs b/egui/src/widgets/slider.rs
index 026aaaa0..d848086d 100644
--- a/egui/src/widgets/slider.rs
+++ b/egui/src/widgets/slider.rs
@@ -91,9 +91,7 @@ impl<'a> Slider<'a> {
     }
 
     fn set_value_f32(&mut self, mut value: f32) {
-        if self.precision == 0 {
-            value = value.round();
-        }
+        value = round_to_precision(value, self.precision);
         (self.get_set_value)(Some(value));
     }
 }