3 files changed, 24 insertions, 23 deletions

diff --git a/src/frontier/image.rs b/src/frontier/image.rs
index 5642297..18bf620 100644
--- a/src/frontier/image.rs
+++ b/src/frontier/image.rs
@@ -1,16 +1,17 @@
 //! Frontier that targets an image.
 
-use super::{Frontier, Pixel};
+use super::{Frontier, Pixel, Target};
 
 use crate::color::{ColorSpace, Rgb8};
-use crate::metric::soft::SoftKdTree;
-use crate::metric::NearestNeighbors;
+use crate::soft::SoftKdTree;
+
+use acap::NearestNeighbors;
 
 use image::RgbImage;
 
 /// A [Frontier] that places colors on the closest pixel of a target image.
 #[derive(Debug)]
-pub struct ImageFrontier<C: ColorSpace> {
+pub struct ImageFrontier<C> {
     nodes: SoftKdTree<Pixel<C>>,
     width: u32,
     height: u32,
@@ -58,7 +59,7 @@ impl<C: ColorSpace> Frontier for ImageFrontier<C> {
     fn place(&mut self, rgb8: Rgb8) -> Option<(u32, u32)> {
         let color = C::from(rgb8);
 
-        if let Some(node) = self.nodes.nearest(&color).map(|n| n.item) {
+        if let Some(node) = self.nodes.nearest(&Target(color)).map(|n| n.item) {
             let pos = node.pos;
 
             node.delete();
diff --git a/src/frontier/mean.rs b/src/frontier/mean.rs
index 6a32b97..3c441b8 100644
--- a/src/frontier/mean.rs
+++ b/src/frontier/mean.rs
@@ -1,19 +1,19 @@
 //! Mean selection frontier.
 
-use super::{neighbors, Frontier, Pixel};
+use super::{neighbors, Frontier, RcPixel, Target};
 
 use crate::color::{ColorSpace, Rgb8};
-use crate::metric::soft::SoftKdForest;
-use crate::metric::NearestNeighbors;
+use crate::soft::SoftKdForest;
+
+use acap::NearestNeighbors;
 
 use std::iter;
-use std::rc::Rc;
 
 /// A pixel on a mean frontier.
 #[derive(Debug)]
 enum MeanPixel<C> {
     Empty,
-    Fillable(Rc<Pixel<C>>),
+    Fillable(RcPixel<C>),
     Filled(C),
 }
 
@@ -27,9 +27,10 @@ impl<C: ColorSpace> MeanPixel<C> {
 }
 
 /// A [Frontier] that looks at the average color of each pixel's neighbors.
+#[derive(Debug)]
 pub struct MeanFrontier<C> {
     pixels: Vec<MeanPixel<C>>,
-    forest: SoftKdForest<Rc<Pixel<C>>>,
+    forest: SoftKdForest<RcPixel<C>>,
     width: u32,
     height: u32,
     len: usize,
@@ -45,7 +46,7 @@ impl<C: ColorSpace> MeanFrontier<C> {
             pixels.push(MeanPixel::Empty);
         }
 
-        let pixel0 = Rc::new(Pixel::new(x0, y0, C::from(Rgb8::from([0, 0, 0]))));
+        let pixel0 = RcPixel::new(x0, y0, C::from(Rgb8::from([0, 0, 0])));
         let i = (x0 + y0 * width) as usize;
         pixels[i] = MeanPixel::Fillable(pixel0.clone());
 
@@ -99,7 +100,7 @@ impl<C: ColorSpace> MeanFrontier<C> {
                         .map(MeanPixel::filled_color)
                         .flatten(),
                 );
-                let pixel = Rc::new(Pixel::new(x, y, color));
+                let pixel = RcPixel::new(x, y, color);
                 self.pixels[i] = MeanPixel::Fillable(pixel.clone());
                 pixels.push(pixel);
             }
@@ -135,7 +136,7 @@ impl<C: ColorSpace> Frontier for MeanFrontier<C> {
 
     fn place(&mut self, rgb8: Rgb8) -> Option<(u32, u32)> {
         let color = C::from(rgb8);
-        let (x, y) = self.forest.nearest(&color).map(|n| n.item.pos)?;
+        let (x, y) = self.forest.nearest(&Target(color)).map(|n| n.item.pos)?;
 
         self.fill(x, y, color);
 
diff --git a/src/frontier/min.rs b/src/frontier/min.rs
index 269f3b7..95b3321 100644
--- a/src/frontier/min.rs
+++ b/src/frontier/min.rs
@@ -1,19 +1,18 @@
 //! Minimum selection frontier.
 
-use super::{neighbors, Frontier, Pixel};
+use super::{neighbors, Frontier, RcPixel, Target};
 
 use crate::color::{ColorSpace, Rgb8};
-use crate::metric::soft::SoftKdForest;
-use crate::metric::NearestNeighbors;
+use crate::soft::SoftKdForest;
 
-use rand::Rng;
+use acap::NearestNeighbors;
 
-use std::rc::Rc;
+use rand::Rng;
 
 /// A pixel on a min frontier.
 #[derive(Debug)]
 struct MinPixel<C> {
-    pixel: Option<Rc<Pixel<C>>>,
+    pixel: Option<RcPixel<C>>,
     filled: bool,
 }
 
@@ -31,7 +30,7 @@ impl<C: ColorSpace> MinPixel<C> {
 pub struct MinFrontier<C, R> {
     rng: R,
     pixels: Vec<MinPixel<C>>,
-    forest: SoftKdForest<Rc<Pixel<C>>>,
+    forest: SoftKdForest<RcPixel<C>>,
     width: u32,
     height: u32,
     x0: u32,
@@ -94,7 +93,7 @@ impl<C: ColorSpace, R: Rng> MinFrontier<C, R> {
             return None;
         }
 
-        let rc = Rc::new(Pixel::new(x, y, color));
+        let rc = RcPixel::new(x, y, color);
         pixel.pixel = Some(rc.clone());
         pixel.filled = true;
 
@@ -144,7 +143,7 @@ impl<C: ColorSpace, R: Rng> Frontier for MinFrontier<C, R> {
         let color = C::from(rgb8);
         let (x, y) = self
             .forest
-            .nearest(&color)
+            .nearest(&Target(color))
             .map(|n| n.item.pos)
             .map(|(x, y)| self.free_neighbor(x, y).unwrap())
             .unwrap_or((self.x0, self.y0));