works well

3 files changed, 71 insertions, 38 deletions

diff --git a/lvc/src/encode.rs b/lvc/src/encode.rs
index d85ac30..5df803b 100644
--- a/lvc/src/encode.rs
+++ b/lvc/src/encode.rs
@@ -1,51 +1,71 @@
 use crate::diff::diff;
+use crate::impls::ToArray;
 use crate::split::split;
 use crate::{Block, Frame, Ref, View};
 
 pub fn encode(last_frame: &Frame, frame: &Frame, view: View) -> Block {
     if view.size().area() > 1024 {
         let [av, bv] = split(view);
-        return Block::Split([
-            Box::new(encode(last_frame, frame, av)),
-            Box::new(encode(last_frame, frame, bv)),
-        ]);
+        return Block::Split(
+            rayon::join(
+                || Box::new(encode(last_frame, frame, av)),
+                || Box::new(encode(last_frame, frame, bv)),
+            )
+            .to_array(),
+        );
     }
 
-    let mut rp = Ref::default();
-    let mut d = diff([last_frame, frame], view, rp);
+    let mut r = Ref::default();
+    let mut d = diff([last_frame, frame], view, r);
 
-    for _ in 0..500 {
-        let (nd, nrp) = optimize_ref(last_frame, frame, view, rp);
-        if nd < d {
-            rp = nrp;
-            d = nd;
-        } else {
-            break;
+    for granularity in [4, 2, 1] {
+        for _ in 0..10 {
+            let (nd, nrp) = optimize_ref(last_frame, frame, view, d, r, granularity);
+            if nd < d {
+                r = nrp;
+                d = nd;
+            } else {
+                break;
+            }
         }
     }
 
     if d < 10000 {
-        return Block::Ref(rp);
+        return Block::Ref(r);
     } else {
         Block::Lit(frame.export(view))
     }
 }
 
-pub fn optimize_ref(last_frame: &Frame, frame: &Frame, view: View, rp: Ref) -> (u32, Ref) {
-    [
-        rp.apply(|r| r.pos_off.x += 1),
-        rp.apply(|r| r.pos_off.x -= 1),
-        rp.apply(|r| r.pos_off.y += 1),
-        rp.apply(|r| r.pos_off.y -= 1),
-        rp.apply(|r| r.color_off.r += 10),
-        rp.apply(|r| r.color_off.r -= 10),
-        rp.apply(|r| r.color_off.g += 10),
-        rp.apply(|r| r.color_off.g -= 10),
-        rp.apply(|r| r.color_off.b += 10),
-        rp.apply(|r| r.color_off.b -= 10),
-    ]
-    .map(|p| (diff([last_frame, frame], view, p), p))
-    .into_iter()
-    .min_by_key(|x| x.0)
-    .unwrap()
+pub fn optimize_ref(
+    last_frame: &Frame,
+    frame: &Frame,
+    view: View,
+    mut d: u32,
+    mut r: Ref,
+    granularity: i32,
+) -> (u32, Ref) {
+    let mut n = |f: fn(&mut Ref, i32)| {
+        let mut r2 = r;
+        f(&mut r2, granularity);
+
+        let d2 = diff([last_frame, frame], view, r2);
+        if d2 < d {
+            d = d2;
+            r = r2;
+        }
+    };
+
+    n(|r, g| r.pos_off.x += g);
+    n(|r, g| r.pos_off.x -= g);
+    n(|r, g| r.pos_off.y += g);
+    n(|r, g| r.pos_off.y -= g);
+    n(|r, g| r.color_off.r += (g as i16) << 2);
+    n(|r, g| r.color_off.r -= (g as i16) << 2);
+    n(|r, g| r.color_off.g += (g as i16) << 2);
+    n(|r, g| r.color_off.g -= (g as i16) << 2);
+    n(|r, g| r.color_off.b += (g as i16) << 2);
+    n(|r, g| r.color_off.b -= (g as i16) << 2);
+
+    (d, r)
 }
diff --git a/lvc/src/impls.rs b/lvc/src/impls.rs
index 0801361..00614c9 100644
--- a/lvc/src/impls.rs
+++ b/lvc/src/impls.rs
@@ -88,7 +88,10 @@ impl Index<P2> for Frame {
     type Output = Pixel;
     #[inline]
     fn index(&self, P2 { x, y }: P2) -> &Self::Output {
-        &self.pixels[x as usize + (y as usize * self.size.x as usize)]
+        &self
+            .pixels
+            .get(x as usize + (y as usize * self.size.x as usize))
+            .unwrap_or(&Pixel { r: 0, g: 0, b: 0 })
     }
 }
 impl IndexMut<P2> for Frame {
@@ -97,3 +100,14 @@ impl IndexMut<P2> for Frame {
         &mut self.pixels[x as usize + (y as usize * self.size.x as usize)]
     }
 }
+
+pub trait ToArray {
+    type Output;
+    fn to_array(self) -> [Self::Output; 2];
+}
+impl<A> ToArray for (A, A) {
+    type Output = A;
+    fn to_array(self) -> [A; 2] {
+        [self.0, self.1]
+    }
+}
diff --git a/lvc/src/lib.rs b/lvc/src/lib.rs
index 4a88b93..d9fdfa3 100644
--- a/lvc/src/lib.rs
+++ b/lvc/src/lib.rs
@@ -2,18 +2,17 @@
 
 use bincode::{Decode, Encode};
 
+#[cfg(test)]
+pub mod bench;
+pub mod debug;
+pub mod decode;
 pub mod diff;
 pub mod encode;
 pub mod impls;
-pub mod decode;
 pub mod split;
-pub mod debug;
-#[cfg(test)]
-pub mod bench;
 
-pub type PixelValue = u8;
+pub type PixelValue = i16;
 
-#[repr(C, align(1))]
 #[derive(Debug, Clone, Copy, Default, Encode, Decode)]
 pub struct Pixel {
     pub r: PixelValue,