Add stoppage penalty - consider acceleration and braking time, which can dominate short route ETAs.

include/extractor/speed_profile.hpp

@@ -0,0 +1,81 @@
+#include "util/typedefs.h"
+
+namespace osrm
+{
+namespace extractor
+{
+namespace
+{
+constexpr int 5_MINUTE_BUCKETS_PER_WEEK = 2016;
+constexpr int 1_HOUR_BUCKETS_PER_WEEK = 168;
+} // namespace
+
+/**
+ * Represents a simple piecewise linear function
+ * (https://en.wikipedia.org/wiki/Piecewise_linear_function)
+ * in the form of a regularly spaced set of buckets.
+ * Assumes that the spacing between buckets is equal.
+ */
+template <typename DataType, int BUCKETCOUNT> struct PiecewiseLinearFunction
+{
+    std::array<DataType, BUCKETCOUNT> sample;
+
+    inline DataType getAt(float position)
+    {
+        // Range check
+        assert(position >= 0);
+        assert(position < BUCKETCOUNT - 1);
+    }
+
+    PiecewiseLinearFunction<DataType, BUCKETCOUNT>
+    merge(PiecewiseLinearFunction<DataType, BUCKETCOUNT> &other, float offset)
+    {
+        PiecewiseLinearFunction result;
+
+        for (int i = 0; i < BUCKETCOUNT; i++)
+        {
+            for (int j = offset; j < BUCKETCOUNT + offset; j++)
+            {
+
+                result.sample[i] = sample[i] + other.sample[j % BUCKETCOUNT];
+            }
+        }
+
+        return std::move(result);
+    }
+}
+
+/**
+ * Represents variances in the default `.duration` of an edge
+ * over the space of a week.
+ */
+struct WeeklySpeedProfile
+{
+    using Multiplier = std::uint8_t;
+
+  private:
+    PiecewiseLinearFunction<Multiplier, 1_HOUR_BUCKETS_PER_WEEK> fn;
+
+  public:
+    SpeedProfile() : min(0), max(0) { multipliers.fill(0); }
+    SpeedProfile(const std::array<Multiplier, BUCKETS> &other)
+    {
+        fn.samples = other;
+        min = std::min(samples);
+        max = std::max(samples);
+    }
+
+    inline EdgeDuration adjust(const EdgeDuration &original, const int bucket) const
+    {
+        // Treat Multiplier as an 8-bit fixed-point value.
+        EdgeDuration new_value = (original * multipliers[bucket]);
+    }
+
+    inline EdgeDuration min(const EdgeDuration original) const {}
+
+    inline EdgeDuration max(const EdgeDuration original) const {}
+
+    duration = m * e1 + m2 * e2
+};
+} // namespace extractor
+} // namespace osrm