update headers to Filament v1.25.0

ios/include/utils/Stopwatch.h

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#ifndef TNT_UTILS_STOPWATCH_H
+#define TNT_UTILS_STOPWATCH_H
+
+#include <utils/Log.h>
+
+#include <chrono>
+#include <limits>
+
+#include <stdint.h>
+
+namespace utils {
+
+/*
+ * A very basic Stopwatch class
+ */
+
+template<typename Clock = std::chrono::steady_clock>
+class Stopwatch {
+public:
+    using duration = typename Clock::duration;
+    using time_point = typename Clock::time_point;
+
+private:
+    time_point mStart;
+    duration mMinLap = std::numeric_limits<duration>::max();
+    duration mMaxLap{};
+    std::chrono::duration<double, std::nano> mAvgLap{};
+    size_t mCount = 0;
+    const char* mName = nullptr;
+
+public:
+    // Create a Stopwatch with a name and clock
+    explicit Stopwatch(const char* name) noexcept: mName(name) {}
+
+    // Logs min/avg/max lap time
+    ~Stopwatch() noexcept;
+
+    // start the stopwatch
+    inline void start() noexcept {
+        mStart = Clock::now();
+    }
+
+    // stop the stopwatch
+    inline void stop() noexcept {
+        auto d = Clock::now() - mStart;
+        mMinLap = std::min(mMinLap, d);
+        mMaxLap = std::max(mMaxLap, d);
+        mAvgLap = (mAvgLap * mCount + d) / (mCount + 1);
+        mCount++;
+    }
+
+    // get the minimum lap time recorded
+    duration getMinLapTime() const noexcept { return mMinLap; }
+
+    // get the maximum lap time recorded
+    duration getMaxLapTime() const noexcept { return mMaxLap; }
+
+    // get the average lap time
+    duration getAverageLapTime() const noexcept { return mAvgLap; }
+};
+
+template<typename Clock>
+Stopwatch<Clock>::~Stopwatch() noexcept {
+    slog.d << "Stopwatch \"" << mName << "\" : ["
+           << mMinLap.count() << ", "
+           << std::chrono::duration_cast<duration>(mAvgLap).count() << ", "
+           << mMaxLap.count() << "] ns" << io::endl;
+}
+
+/*
+ * AutoStopwatch can be used to start and stop a Stopwatch automatically
+ * when entering and exiting a scope.
+ */
+template<typename Stopwatch>
+class AutoStopwatch {
+    Stopwatch& stopwatch;
+public:
+    inline explicit AutoStopwatch(Stopwatch& stopwatch) noexcept: stopwatch(stopwatch) {
+        stopwatch.start();
+    }
+
+    inline ~AutoStopwatch() noexcept { stopwatch.stop(); }
+};
+
+} // namespace utils
+
+#endif // TNT_UTILS_STOPWATCH_H