zero copy texture write

1 files changed, 20 insertions, 2 deletions

diff --git a/shared/src/helper.rs b/shared/src/helper.rs
index d267f68..eb1f321 100644
--- a/shared/src/helper.rs
+++ b/shared/src/helper.rs
@@ -18,6 +18,7 @@ use crate::packets::{Data, Object, Resource};
 use anyhow::Result;
 use glam::{Affine3A, Vec2, Vec3A};
 use std::{
+    borrow::Cow,
     io::{Read, Write},
     marker::PhantomData,
 };
@@ -26,10 +27,10 @@ pub trait ReadWrite: Sized {
     fn write(&self, w: &mut dyn Write) -> Result<()>;
     fn read(r: &mut dyn Read) -> Result<Self>;
 
-    fn write_alloc(&self) -> Vec<u8> {
+    fn write_alloc<'a>(&'a self) -> Cow<'a, [u8]> {
         let mut buf = Vec::new();
         self.write(&mut buf).unwrap();
-        buf
+        Cow::Owned(buf)
     }
 }
 
@@ -66,6 +67,23 @@ impl ReadWrite for Vec<u8> {
         Ok(buf)
     }
 }
+impl<'a> ReadWrite for Cow<'a, [u8]> {
+    fn write(&self, w: &mut dyn Write) -> Result<()> {
+        w.write_all(&self)?;
+        Ok(())
+    }
+    fn read(r: &mut dyn Read) -> Result<Self> {
+        let mut buf = Vec::new();
+        r.read_to_end(&mut buf)?;
+        Ok(Cow::Owned(buf))
+    }
+    fn write_alloc<'b>(&'b self) -> Cow<'b, [u8]> {
+        match self {
+            Cow::Borrowed(x) => Cow::Borrowed(x),
+            Cow::Owned(x) => Cow::Borrowed(&x),
+        }
+    }
+}
 impl ReadWrite for Vec<Vec3A> {
     fn write(&self, w: &mut dyn Write) -> Result<()> {
         for e in self {