1 files changed, 43 insertions, 0 deletions
diff --git a/externals/oboe/apps/OboeTester/app/src/main/cpp/InterpolatingDelayLine.cpp b/externals/oboe/apps/OboeTester/app/src/main/cpp/InterpolatingDelayLine.cpp
new file mode 100644
index 0000000000..f5393c57bd
--- /dev/null
+++ b/externals/oboe/apps/OboeTester/app/src/main/cpp/InterpolatingDelayLine.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2019 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 <algorithm>
+
+#include "InterpolatingDelayLine.h"
+
+InterpolatingDelayLine::InterpolatingDelayLine(int32_t delaySize) {
+    mDelaySize = delaySize;
+    mDelayLine = std::make_unique<float[]>(delaySize);
+}
+
+float InterpolatingDelayLine::process(float delay, float input) {
+    float *writeAddress = mDelayLine.get() + mCursor;
+    *writeAddress = input;
+    mDelayLine.get()[mCursor] = input;
+    int32_t delayInt = std::min(mDelaySize - 1, (int32_t) delay);
+    int32_t readIndex = mCursor - delayInt;
+    if (readIndex < 0) {
+        readIndex += mDelaySize;
+    }
+    // TODO interpolate
+    float *readAddress = mDelayLine.get() + readIndex;
+    float output = *readAddress;
+    mCursor++;
+    if (mCursor >= mDelaySize) {
+        mCursor = 0;
+    }
+    return output;
+};