osrm-backend/Algorithms/PolylineCompressor.h
2013-08-14 13:12:28 +02:00

137 lines
4.5 KiB
C++

/*
open source routing machine
Copyright (C) Dennis Luxen, others 2010
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU AFFERO General Public License as published by
the Free Software Foundation; either version 3 of the License, or
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
or see http://www.gnu.org/licenses/agpl.txt.
*/
#ifndef POLYLINECOMPRESSOR_H_
#define POLYLINECOMPRESSOR_H_
#include "../DataStructures/SegmentInformation.h"
#include "../Util/StringUtil.h"
#include <string>
class PolylineCompressor {
private:
inline void encodeVectorSignedNumber(std::vector<int> & numbers, std::string & output) const {
for(unsigned i = 0; i < numbers.size(); ++i) {
numbers[i] <<= 1;
if (numbers[i] < 0) {
numbers[i] = ~(numbers[i]);
}
}
for(unsigned i = 0; i < numbers.size(); ++i) {
encodeNumber(numbers[i], output);
}
}
inline void encodeNumber(int numberToEncode, std::string & output) const {
while (numberToEncode >= 0x20) {
int nextValue = (0x20 | (numberToEncode & 0x1f)) + 63;
output += (static_cast<char> (nextValue));
if(92 == nextValue)
output += (static_cast<char> (nextValue));
numberToEncode >>= 5;
}
numberToEncode += 63;
output += (static_cast<char> (numberToEncode));
if(92 == numberToEncode)
output += (static_cast<char> (numberToEncode));
}
public:
inline void printEncodedString(
const std::vector<SegmentInformation> & polyline,
std::string & output
) const {
std::vector<int> deltaNumbers;
output += "\"";
if(!polyline.empty()) {
FixedPointCoordinate lastCoordinate = polyline[0].location;
deltaNumbers.push_back( lastCoordinate.lat );
deltaNumbers.push_back( lastCoordinate.lon );
for(unsigned i = 1; i < polyline.size(); ++i) {
if(!polyline[i].necessary)
continue;
deltaNumbers.push_back(polyline[i].location.lat - lastCoordinate.lat);
deltaNumbers.push_back(polyline[i].location.lon - lastCoordinate.lon);
lastCoordinate = polyline[i].location;
}
encodeVectorSignedNumber(deltaNumbers, output);
}
output += "\"";
}
inline void printEncodedString(const std::vector<FixedPointCoordinate>& polyline, std::string &output) const {
std::vector<int> deltaNumbers(2*polyline.size());
output += "\"";
if(!polyline.empty()) {
deltaNumbers[0] = polyline[0].lat;
deltaNumbers[1] = polyline[0].lon;
for(unsigned i = 1; i < polyline.size(); ++i) {
deltaNumbers[(2*i)] = (polyline[i].lat - polyline[i-1].lat);
deltaNumbers[(2*i)+1] = (polyline[i].lon - polyline[i-1].lon);
}
encodeVectorSignedNumber(deltaNumbers, output);
}
output += "\"";
}
inline void printUnencodedString(std::vector<FixedPointCoordinate> & polyline, std::string & output) const {
output += "[";
std::string tmp;
for(unsigned i = 0; i < polyline.size(); i++) {
convertInternalLatLonToString(polyline[i].lat, tmp);
output += "[";
output += tmp;
convertInternalLatLonToString(polyline[i].lon, tmp);
output += ", ";
output += tmp;
output += "]";
if( i < polyline.size()-1 ) {
output += ",";
}
}
output += "]";
}
inline void printUnencodedString(std::vector<SegmentInformation> & polyline, std::string & output) const {
output += "[";
std::string tmp;
for(unsigned i = 0; i < polyline.size(); i++) {
if(!polyline[i].necessary)
continue;
convertInternalLatLonToString(polyline[i].location.lat, tmp);
output += "[";
output += tmp;
convertInternalLatLonToString(polyline[i].location.lon, tmp);
output += ", ";
output += tmp;
output += "]";
if( i < polyline.size()-1 ) {
output += ",";
}
}
output += "]";
}
};
#endif /* POLYLINECOMPRESSOR_H_ */