src/dawn_native/metal/CommandRecordingContext.h

// Copyright 2020 The Dawn Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef DAWNNATIVE_METAL_COMMANDRECORDINGCONTEXT_H_
#define DAWNNATIVE_METAL_COMMANDRECORDINGCONTEXT_H_

#include "common/NSRef.h"
#include "common/NonCopyable.h"
#include "dawn_native/Error.h"

#import <Metal/Metal.h>

namespace dawn_native::metal {

    // This class wraps a MTLCommandBuffer and tracks which Metal encoder is open.
    // Only one encoder may be open at a time.
    class CommandRecordingContext : NonMovable {
      public:
        CommandRecordingContext();
        ~CommandRecordingContext();

        id<MTLCommandBuffer> GetCommands();
        void MarkUsed();
        bool WasUsed() const;

        MaybeError PrepareNextCommandBuffer(id<MTLCommandQueue> queue);
        NSPRef<id<MTLCommandBuffer>> AcquireCommands();

        id<MTLBlitCommandEncoder> EnsureBlit();
        void EndBlit();

        id<MTLComputeCommandEncoder> BeginCompute();
        void EndCompute();

        id<MTLRenderCommandEncoder> BeginRender(MTLRenderPassDescriptor* descriptor);
        void EndRender();

      private:
        NSPRef<id<MTLCommandBuffer>> mCommands;
        NSPRef<id<MTLBlitCommandEncoder>> mBlit;
        NSPRef<id<MTLComputeCommandEncoder>> mCompute;
        NSPRef<id<MTLRenderCommandEncoder>> mRender;
        bool mInEncoder = false;
        bool mUsed = false;
    };

}  // namespace dawn_native::metal

#endif  // DAWNNATIVE_METAL_COMMANDRECORDINGCONTEXT_H_