1 files changed, 41 insertions, 0 deletions
diff --git a/system/hwc3/AlternatingImageStorage.cpp b/system/hwc3/AlternatingImageStorage.cpp
new file mode 100644
index 00000000..6ca2b0b1
--- /dev/null
+++ b/system/hwc3/AlternatingImageStorage.cpp
@@ -0,0 +1,41 @@
+/*
+ * Copyright 2023 The Android Open Source Project
+ *
+ * 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.
+ */
+
+#include "AlternatingImageStorage.h"
+
+namespace aidl::android::hardware::graphics::composer3::impl {
+
+uint8_t* AlternatingImageStorage::getRotatingScratchBuffer(std::size_t neededSize,
+                                                           std::uint32_t imageIndex) {
+  std::size_t totalNeededSize = neededSize * kNumScratchBufferPieces;
+  if (mScratchBuffer.size() < totalNeededSize) {
+    mScratchBuffer.resize(totalNeededSize);
+  }
+
+  std::size_t bufferIndex = imageIndex % kNumScratchBufferPieces;
+  std::size_t bufferOffset = bufferIndex * neededSize;
+  return &mScratchBuffer[bufferOffset];
+}
+
+uint8_t* AlternatingImageStorage::getSpecialScratchBuffer(size_t neededSize) {
+  if (mSpecialScratchBuffer.size() < neededSize) {
+    mSpecialScratchBuffer.resize(neededSize);
+  }
+
+  return &mSpecialScratchBuffer[0];
+}
+
+}  // namespace aidl::android::hardware::graphics::composer3::impl