rename + readme

1 files changed, 116 insertions, 0 deletions

diff --git a/bv1/codec/src/serialize.rs b/bv1/codec/src/serialize.rs
new file mode 100644
index 0000000..960aa1b
--- /dev/null
+++ b/bv1/codec/src/serialize.rs
@@ -0,0 +1,116 @@
+use crate::{split::split, Block, Pixel, Ref, View, P2};
+use std::io::{Read, Result, Write};
+
+impl Pixel {
+    #[inline]
+    pub fn write(&self, w: &mut impl Write) -> Result<()> {
+        w.write_all(&[
+            self.r.clamp(0, 255) as u8,
+            self.g.clamp(0, 255) as u8,
+            self.b.clamp(0, 255) as u8,
+        ])
+    }
+    #[inline]
+    pub fn read(r: &mut impl Read) -> Result<Pixel> {
+        Ok(Self {
+            r: read_byte(r)? as i16,
+            g: read_byte(r)? as i16,
+            b: read_byte(r)? as i16,
+        })
+    }
+}
+impl Pixel {
+    #[inline]
+    pub fn write_full(&self, w: &mut impl Write) -> Result<()> {
+        write_word(w, self.r)?;
+        write_word(w, self.g)?;
+        write_word(w, self.b)?;
+        Ok(())
+    }
+    #[inline]
+    pub fn read_full(r: &mut impl Read) -> Result<Pixel> {
+        Ok(Self {
+            r: read_word(r)?,
+            g: read_word(r)?,
+            b: read_word(r)?,
+        })
+    }
+}
+impl P2 {
+    #[inline]
+    pub fn write(&self, w: &mut impl Write) -> Result<()> {
+        write_word(w, self.x as i16)?;
+        write_word(w, self.y as i16)?;
+        Ok(())
+    }
+
+    #[inline]
+    pub fn read(r: &mut impl Read) -> Result<P2> {
+        Ok(Self {
+            x: read_word(r)? as i32,
+            y: read_word(r)? as i32,
+        })
+    }
+}
+
+impl Block {
+    pub fn write(&self, w: &mut impl Write) -> Result<()> {
+        match self {
+            Block::Split(a, b) => {
+                w.write_all(&[0])?;
+                a.write(w)?;
+                b.write(w)?;
+            }
+            Block::Lit(pixels) => {
+                w.write_all(&[1])?;
+                for p in pixels {
+                    p.write(w)?;
+                }
+            }
+            Block::Ref(k) => {
+                w.write_all(&[2])?;
+                k.pos_off.write(w)?;
+                k.color_off.write_full(w)?;
+            }
+        }
+        Ok(())
+    }
+    pub fn read(r: &mut impl Read, view: View) -> Result<Block> {
+        match read_byte(r)? {
+            0 => {
+                let [av, bv] = split(view);
+                Ok(Block::Split(
+                    box Block::read(r, av)?,
+                    box Block::read(r, bv)?,
+                ))
+            }
+            1 => {
+                let mut px = vec![];
+                for _ in 0..view.size().area() {
+                    px.push(Pixel::read(r)?)
+                }
+                Ok(Block::Lit(px))
+            }
+            2 => Ok(Block::Ref(Ref {
+                pos_off: P2::read(r)?,
+                color_off: Pixel::read_full(r)?,
+            })),
+            _ => Err(std::io::Error::other("unknown block variant")),
+        }
+    }
+}
+
+#[inline]
+fn read_byte(r: &mut impl Read) -> Result<u8> {
+    let mut buf = [0u8];
+    r.read_exact(&mut buf)?;
+    Ok(buf[0])
+}
+#[inline]
+fn write_word(w: &mut impl Write, v: i16) -> Result<()> {
+    w.write_all(&[(v & 0xff) as u8, (v >> 8) as u8])
+}
+#[inline]
+fn read_word(r: &mut impl Read) -> Result<i16> {
+    Ok((read_byte(r)? as u16 | ((read_byte(r)? as u16) << 8)) as i16)
+}