Merge #2461

2461: Added supports_transfer function. r=kvark a=bbrown683

Fixes #issue
PR checklist:
- [ ] `make` succeeds (on *nix)
- [ ] `make reftests` succeeds
- [ ] tested examples with the following backends:
- [ ] `rustfmt` run on changed code

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Co-authored-by: Ben Brown <[email protected]>

src/hal/src/queue/capability.rs

@@ -50,7 +50,11 @@ impl Capability for Compute {
 impl Capability for Transfer {
     fn supported_by(qt: QueueType) -> bool {
         match qt {
-            _ => true
+            QueueType::General |
+            QueueType::Compute |
+            QueueType::Graphics |
+            QueueType::Transfer => true,
+            _ => false,
         }
     }
 }

src/hal/src/queue/family.rs

@@ -3,7 +3,7 @@
 use Backend;
 use backend::RawQueueGroup;
 use queue::{CommandQueue, QueueType};
-use queue::capability::{Capability, Graphics, Compute};
+use queue::capability::{Capability, Graphics, Compute, Transfer};
 
 use std::any::Any;
 use std::fmt::Debug;
@@ -20,10 +20,14 @@ pub trait QueueFamily: Debug + Any + Send + Sync {
     fn supports_graphics(&self) -> bool {
         Graphics::supported_by(self.queue_type())
     }
-    /// Returns true if the queue supports graphics operations.
+    /// Returns true if the queue supports compute operations.
     fn supports_compute(&self) -> bool {
         Compute::supported_by(self.queue_type())
     }
+    /// Returns true if the queue supports transfer operations.
+    fn supports_transfer(&self) -> bool {
+        Transfer::supported_by(self.queue_type())
+    }
     /// Returns the queue family ID.
     fn id(&self) -> QueueFamilyId;
 }