[slider] round so what you see is what you get

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)
+}

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));
     }
 }