diff --git a/src/param.rs b/src/param.rs
index 7d749a8e..640edb95 100644
--- a/src/param.rs
+++ b/src/param.rs
@@ -72,6 +72,14 @@ pub trait Param {
     /// Get the string representation for a normalized value. Used as part of the wrappers.
     fn string_to_normalized_value(&self, string: &str) -> Option<f32>;
 
+    /// Get the normalized value for a plain, unnormalized value, as a float. Used as part of the
+    /// wrappers.
+    fn preview_normalized(&self, plain: Self::Plain) -> f32;
+
+    /// Get the plain, unnormalized value for a normalized value, as a float. Used as part of the
+    /// wrappers.
+    fn preview_plain(&self, normalized: f32) -> Self::Plain;
+
     /// Internal implementation detail for implementing [internals::Params]. This should not be used
     /// directly.
     fn as_ptr(&self) -> internals::ParamPtr;
@@ -227,6 +235,14 @@ macro_rules! impl_plainparam {
                 Some(self.range.normalize(value))
             }
 
+            fn preview_normalized(&self, plain: Self::Plain) -> f32 {
+                self.range.normalize(plain)
+            }
+
+            fn preview_plain(&self, normalized: f32) -> Self::Plain {
+                self.range.unnormalize(normalized)
+            }
+
             fn as_ptr(&self) -> internals::ParamPtr {
                 internals::ParamPtr::$ty(self as *const $ty as *mut $ty)
             }
@@ -300,6 +316,18 @@ impl Param for BoolParam {
         Some(if value { 1.0 } else { 0.0 })
     }
 
+    fn preview_normalized(&self, plain: Self::Plain) -> f32 {
+        if plain {
+            1.0
+        } else {
+            0.0
+        }
+    }
+
+    fn preview_plain(&self, normalized: f32) -> Self::Plain {
+        normalized > 0.5
+    }
+
     fn as_ptr(&self) -> internals::ParamPtr {
         internals::ParamPtr::BoolParam(self as *const BoolParam as *mut BoolParam)
     }
diff --git a/src/param/internals.rs b/src/param/internals.rs
index e13aa1c9..d682912c 100644
--- a/src/param/internals.rs
+++ b/src/param/internals.rs
@@ -19,7 +19,7 @@
 use std::collections::HashMap;
 use std::pin::Pin;
 
-use super::{NormalizebleRange, Param};
+use super::Param;
 
 /// Re-export for use in the [Params] proc-macro.
 pub use serde_json::from_str as deserialize_field;
@@ -191,8 +191,8 @@ impl ParamPtr {
     /// still alive.
     pub unsafe fn preview_normalized(&self, plain: f32) -> f32 {
         match &self {
-            ParamPtr::FloatParam(p) => (**p).range.normalize(plain),
-            ParamPtr::IntParam(p) => (**p).range.normalize(plain as i32),
+            ParamPtr::FloatParam(p) => (**p).preview_normalized(plain),
+            ParamPtr::IntParam(p) => (**p).preview_normalized(plain as i32),
             ParamPtr::BoolParam(_) => plain,
         }
     }
@@ -206,8 +206,8 @@ impl ParamPtr {
     /// still alive.
     pub unsafe fn preview_plain(&self, normalized: f32) -> f32 {
         match &self {
-            ParamPtr::FloatParam(p) => (**p).range.unnormalize(normalized),
-            ParamPtr::IntParam(p) => (**p).range.unnormalize(normalized) as f32,
+            ParamPtr::FloatParam(p) => (**p).preview_plain(normalized),
+            ParamPtr::IntParam(p) => (**p).preview_plain(normalized) as f32,
             ParamPtr::BoolParam(_) => normalized,
         }
     }