Merge pull request #3922 from bykoianko/master-saving-altitude-from-previous

Using DeltaCoder bit writer to save altitude.

generator/altitude_generator.cpp

@@ -213,6 +213,7 @@ void BuildRoadAltitudes(string const & mwmPath, AltitudeGetter & altitudeGetter)
     // Writing altitude info.
     header.m_altitudesOffset = w.Pos() - startOffset;
     w.Write(deltas.data(), deltas.size());
+    w.WritePaddingByEnd(8);
     header.m_endOffset = w.Pos() - startOffset;
 
     // Rewriting header info.
@@ -220,8 +221,7 @@ void BuildRoadAltitudes(string const & mwmPath, AltitudeGetter & altitudeGetter)
     w.Seek(startOffset);
     header.Serialize(w);
     w.Seek(endOffset);
-    LOG(LINFO, (ALTITUDES_FILE_TAG, "section is ready. The size is", endOffset - startOffset,
-                "min altitude is", processor.GetMinAltitude()));
+    LOG(LINFO, (ALTITUDES_FILE_TAG, "section is ready. The size is", header.m_endOffset));
     if (processor.HasAltitudeInfo())
       LOG(LINFO, ("Min altitude is", processor.GetMinAltitude()));
     else

indexer/altitude_loader.cpp

@@ -31,6 +31,8 @@ namespace feature
 {
 AltitudeLoader::AltitudeLoader(MwmValue const & mwmValue)
 {
+  m_countryFileName = mwmValue.GetCountryFileName();
+
   if (mwmValue.GetHeader().GetFormat() < version::Format::v8)
     return;
 
@@ -50,7 +52,7 @@ AltitudeLoader::AltitudeLoader(MwmValue const & mwmValue)
   catch (Reader::OpenException const & e)
   {
     m_header.Reset();
-    LOG(LERROR, ("Error while reading", ALTITUDES_FILE_TAG, "section.", e.Msg()));
+    LOG(LERROR, ("File", m_countryFileName, "Error while reading", ALTITUDES_FILE_TAG, "section.", e.Msg()));
   }
 }
 
@@ -73,31 +75,34 @@ TAltitudes const & AltitudeLoader::GetAltitudes(uint32_t featureId, size_t point
 
   if (!m_altitudeAvailability[featureId])
   {
-    LOG(LINFO, ("Feature featureId =", featureId, "does not contain any altitude information."));
+    LOG(LDEBUG, ("Feature Id", featureId, "of", m_countryFileName,
+                 "does not contain any altitude information."));
     return m_cache.insert(make_pair(featureId, TAltitudes(pointCount, m_header.m_minAltitude))).first->second;
   }
 
   uint64_t const r = m_altitudeAvailability.rank(featureId);
-  CHECK_LESS(r, m_altitudeAvailability.size(), (featureId));
+  CHECK_LESS(r, m_altitudeAvailability.size(), ("Feature Id", featureId, "of", m_countryFileName));
   uint64_t const offset = m_featureTable.select(r);
-  CHECK_LESS_OR_EQUAL(offset, m_featureTable.size(), (featureId));
+  CHECK_LESS_OR_EQUAL(offset, m_featureTable.size(), ("Feature Id", featureId, "of", m_countryFileName));
 
   uint64_t const altitudeInfoOffsetInSection = m_header.m_altitudesOffset + offset;
-  CHECK_LESS(altitudeInfoOffsetInSection, m_reader->Size(), ());
+  CHECK_LESS(altitudeInfoOffsetInSection, m_reader->Size(), ("Feature Id", featureId, "of", m_countryFileName));
 
   try
   {
     Altitudes altitudes;
     ReaderSource<FilesContainerR::TReader> src(*m_reader);
     src.Skip(altitudeInfoOffsetInSection);
-    bool const isDeserialized = altitudes.Deserialize(m_header.m_minAltitude, pointCount, src);
+    bool const isDeserialized = altitudes.Deserialize(m_header.m_minAltitude, pointCount,
+                                                      m_countryFileName, featureId,  src);
 
     bool const allValid = isDeserialized
         && none_of(altitudes.m_altitudes.begin(), altitudes.m_altitudes.end(),
                    [](TAltitude a) { return a == kInvalidAltitude; });
     if (!allValid)
     {
-      ASSERT(false, (altitudes.m_altitudes));
+      LOG(LERROR, ("Only a part point of a feature has a valid altitdue. Altitudes: ", altitudes.m_altitudes,
+                   ". Feature Id", featureId, "of", m_countryFileName));
       return m_cache.insert(make_pair(featureId, TAltitudes(pointCount, m_header.m_minAltitude))).first->second;
     }
 
@@ -105,7 +110,7 @@ TAltitudes const & AltitudeLoader::GetAltitudes(uint32_t featureId, size_t point
   }
   catch (Reader::OpenException const & e)
   {
-    LOG(LERROR, ("Error while getting altitude data", e.Msg()));
+    LOG(LERROR, ("Feature Id", featureId, "of", m_countryFileName, ". Error while getting altitude data:", e.Msg()));
     return m_cache.insert(make_pair(featureId, TAltitudes(pointCount, m_header.m_minAltitude))).first->second;
   }
 }

indexer/altitude_loader.hpp

@@ -4,6 +4,7 @@
 
 #include "coding/memory_region.hpp"
 
+#include "std/string.hpp"
 #include "std/unique_ptr.hpp"
 #include "std/vector.hpp"
 
@@ -32,5 +33,6 @@ private:
   unique_ptr<FilesContainerR::TReader> m_reader;
   map<uint32_t, TAltitudes> m_cache;
   AltitudeHeader m_header;
+  string m_countryFileName;
 };
 }  // namespace feature

indexer/feature_altitude.hpp

@@ -1,9 +1,13 @@
 #pragma once
+
+#include "coding/bit_streams.hpp"
+#include "coding/elias_coder.hpp"
 #include "coding/reader.hpp"
 #include "coding/varint.hpp"
 #include "coding/write_to_sink.hpp"
 
 #include "base/assert.hpp"
+#include "base/bits.hpp"
 
 #include "std/cstdint.hpp"
 #include "std/limits.hpp"
@@ -51,7 +55,7 @@ struct AltitudeHeader
 
   size_t GetFeatureTableSize() const { return m_altitudesOffset - m_featureTableOffset; }
 
-  size_t GetAltitudeInfo() const { return m_endOffset - m_altitudesOffset; }
+  size_t GetAltitudeInfoSize() const { return m_endOffset - m_altitudesOffset; }
 
   void Reset()
   {
@@ -83,32 +87,46 @@ public:
   {
     CHECK(!m_altitudes.empty(), ());
 
-    WriteVarInt(sink, static_cast<int32_t>(m_altitudes[0]) - static_cast<int32_t>(minAltitude));
-    for (size_t i = 1; i < m_altitudes.size(); ++i)
+    BitWriter<TSink> bits(sink);
+    TAltitude prevAltitude = minAltitude;
+    for (auto const altitude : m_altitudes)
     {
-      WriteVarInt(sink,
-                  static_cast<int32_t>(m_altitudes[i]) - static_cast<int32_t>(m_altitudes[i - 1]));
+      CHECK_LESS_OR_EQUAL(minAltitude, altitude, ("A point altitude is less than min mwm altitude"));
+      uint32_t const delta = bits::ZigZagEncode(static_cast<int32_t>(altitude) -
+                                                static_cast<int32_t>(prevAltitude));
+      coding::DeltaCoder::Encode(bits, delta + 1 /* making it greater than zero */);
+      prevAltitude = altitude;
     }
   }
 
   template <class TSource>
-  bool Deserialize(TAltitude minAltitude, size_t pointCount, TSource & src)
+  bool Deserialize(TAltitude minAltitude, size_t pointCount, string const & countryFileName,
+                   uint32_t featureId, TSource & src)
   {
-    m_altitudes.clear();
-    if (pointCount == 0)
-    {
-      ASSERT(false, ());
-      return false;
-    }
+    ASSERT_NOT_EQUAL(pointCount, 0, ());
 
-    m_altitudes.resize(pointCount);
+    BitReader<TSource> bits(src);
     TAltitude prevAltitude = minAltitude;
+    m_altitudes.resize(pointCount);
+
     for (size_t i = 0; i < pointCount; ++i)
     {
-      m_altitudes[i] = static_cast<TAltitude>(ReadVarInt<int32_t>(src) + prevAltitude);
+      uint32_t const biasedDelta = coding::DeltaCoder::Decode(bits);
+      if (biasedDelta == 0)
+      {
+        LOG(LERROR, ("Decoded altitude delta is zero. File", countryFileName,
+                     ". Feature Id", featureId, ". Point number in the feature", i, "."));
+        m_altitudes.clear();
+        return false;
+      }
+      uint32_t const delta = biasedDelta - 1;
+
+      m_altitudes[i] = static_cast<TAltitude>(bits::ZigZagDecode(delta) + prevAltitude);
       if (m_altitudes[i] < minAltitude)
       {
-        ASSERT(false, ());
+        LOG(LERROR, ("A point altitude read from file(", m_altitudes[i],
+                     ") is less than min mwm altitude(", minAltitude, "). File ",
+                     countryFileName, ". Feature Id", featureId, ". Point number in the feature", i, "."));
         m_altitudes.clear();
         return false;
       }