Vk: ad a Queue::submit() returning a Fence.

I originally had this API there but then threw it away because it
encouraged inefficient use. However now it's really handy when writing
tests, so I guess I'll keep it.

src/Magnum/Vk/Queue.cpp

@@ -31,6 +31,7 @@
 
 #include "Magnum/Vk/Assert.h"
 #include "Magnum/Vk/Device.h"
+#include "Magnum/Vk/Fence.h"
 
 namespace Magnum { namespace Vk {
 
@@ -83,6 +84,16 @@ void Queue::submit(std::initializer_list<Containers::Reference<const SubmitInfo>
     return submit(Containers::arrayView(infos), fence);
 }
 
+Fence Queue::submit(const Containers::ArrayView<const Containers::Reference<const SubmitInfo>> infos) {
+    Vk::Fence fence{*_device};
+    submit(infos, fence);
+    return fence;
+}
+
+Fence Queue::submit(const std::initializer_list<Containers::Reference<const SubmitInfo>> infos) {
+    return submit(Containers::arrayView(infos));
+}
+
 struct SubmitInfo::State {
     Containers::Array<VkCommandBuffer> commandBuffers;
 };

src/Magnum/Vk/Queue.h

@@ -118,6 +118,24 @@ class MAGNUM_VK_EXPORT Queue {
         /** @overload */
         void submit(std::initializer_list<Containers::Reference<const SubmitInfo>> infos, VkFence fence);
 
+        /**
+         * @brief Submit a sequence of semaphores or command buffers to a queue and return a new fence to wait on
+         *
+         * Compared to @ref submit(Containers::ArrayView<const Containers::Reference<const SubmitInfo>>, VkFence)
+         * creates a new @ref Fence and returns it for a more convenient
+         * one-off submission.
+         *
+         * @m_class{m-note m-success}
+         *
+         * @par
+         *      When submitting multiple times it's recommended to
+         *      @ref Fence::reset() "reset()" an existing fence and reuse it
+         *      instead of letting this function create a new one every time.
+         */
+        Fence submit(Containers::ArrayView<const Containers::Reference<const SubmitInfo>> infos);
+        /** @overload */
+        Fence submit(std::initializer_list<Containers::Reference<const SubmitInfo>> infos);
+
     private:
         /* Can't be a reference because of the NoCreate constructor */
         Device* _device;
@@ -145,6 +163,10 @@ class MAGNUM_VK_EXPORT SubmitInfo {
          */
         explicit SubmitInfo();
 
+        /** @todo implicit constructor taking the command buffer list directly,
+            needs AnyReference first because queue.submit({{a}}) would now fail
+            on deleted Reference(T&&) */
+
         /**
          * @brief Construct without initializing the contents
          *

src/Magnum/Vk/Test/QueueVkTest.cpp

@@ -41,11 +41,13 @@ struct QueueVkTest: VulkanTester {
 
     void submit();
     void submitOne();
+    void submitImplicitFence();
 };
 
 QueueVkTest::QueueVkTest() {
     addTests({&QueueVkTest::submit,
-              &QueueVkTest::submitOne});
+              &QueueVkTest::submitOne,
+              &QueueVkTest::submitImplicitFence});
 }
 
 void QueueVkTest::submit() {
@@ -97,6 +99,18 @@ void QueueVkTest::submitOne() {
     CORRADE_VERIFY(fence.wait(std::chrono::milliseconds{1000}));
 }
 
+void QueueVkTest::submitImplicitFence() {
+    CommandPool pool{device(), CommandPoolCreateInfo{
+        device().properties().pickQueueFamily(QueueFlag::Graphics)}};
+
+    CommandBuffer a = pool.allocate();
+    a.begin()
+     .end();
+
+    CORRADE_VERIFY(queue().submit({SubmitInfo{}.setCommandBuffers({a})})
+        .wait(std::chrono::milliseconds{1000}));
+}
+
 }}}}
 
 CORRADE_TEST_MAIN(Magnum::Vk::Test::QueueVkTest)