[rs] Implement more derives for Operations (gfx-rs#450)

* Implement more derives for `Operations`

* Use `trace` / `replay` features for serialization

* Set `store` to default

Author: GabrielMajeri

wgpu/Cargo.toml

@@ -17,8 +17,8 @@ all-features = true
 
 [features]
 default = []
-trace = ["wgc/trace"]
-replay = ["wgc/replay"]
+trace = ["serde", "wgc/trace"]
+replay = ["serde", "wgc/replay"]
 subscriber = ["wgc/subscriber"]
 # Make Vulkan backend available on platforms where it is by default not, e.g. macOS
 vulkan = ["wgc/gfx-backend-vulkan"]
@@ -44,6 +44,7 @@ raw-window-handle = "0.3"
 smallvec = "1"
 tracing = { version = "0.1", default-features = false, features = ["std"] }
 typed-arena = "2.0.1"
+serde = { version = "1", features = ["derive"], optional = true }
 
 #Note: we may consider switching this to "dev-dependencies" if users
 # want to opt into X11 explicitly.

wgpu/src/lib.rs

@@ -22,6 +22,10 @@ use std::{
 
 use futures::FutureExt as _;
 use parking_lot::Mutex;
+#[cfg(feature = "trace")]
+use serde::Serialize;
+#[cfg(feature = "replay")]
+use serde::Deserialize;
 
 #[cfg(not(target_arch = "wasm32"))]
 pub use wgc::instance::{AdapterInfo, DeviceType};
@@ -797,23 +801,42 @@ pub enum BindingResource<'a> {
 }
 
 /// Operation to perform to the output attachment at the start of a renderpass.
-#[derive(Clone, Copy, Debug, Hash, PartialEq)]
+#[derive(Copy, Clone, Debug, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "trace", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
 pub enum LoadOp<V> {
     /// Clear with a specified value.
     Clear(V),
     /// Load from memory.
     Load,
 }
 
+impl<V: Default> Default for LoadOp<V> {
+    fn default() -> Self {
+        Self::Clear(Default::default())
+    }
+}
+
 /// Pair of load and store operations for an attachment aspect.
-#[derive(Clone, Debug, Hash, PartialEq)]
+#[derive(Copy, Clone, Debug, Hash, Eq, PartialEq)]
+#[cfg_attr(feature = "trace", derive(Serialize))]
+#[cfg_attr(feature = "replay", derive(Deserialize))]
 pub struct Operations<V> {
     /// How data should be read through this attachment.
     pub load: LoadOp<V>,
     /// Whether data will be written to through this attachment.
     pub store: bool,
 }
 
+impl<V: Default> Default for Operations<V> {
+    fn default() -> Self {
+        Self {
+            load: Default::default(),
+            store: true,
+        }
+    }
+}
+
 /// Describes a color attachment to a [`RenderPass`].
 #[derive(Clone)]
 pub struct RenderPassColorAttachmentDescriptor<'a> {