qgspointcloudlayereditutils.cpp

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/***************************************************************************
    qgspointcloudlayereditutils.cpp
    ---------------------
    begin                : December 2024
    copyright            : (C) 2024 by Stefanos Natsis
    email                : uclaros at gmail dot com
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
 
#include "qgspointcloudlayereditutils.h"
#include "qgslazdecoder.h"
#include "qgscopcpointcloudindex.h"
 
#include <lazperf/readers.hpp>
#include <lazperf/writers.hpp>
 
 
static void updatePoint( char *pointBuffer, int pointFormat, const QString &attributeName, double newValue )
{
  if ( attributeName == QLatin1String( "Intensity" ) )  // unsigned short
  {
    quint16 newValueShort = static_cast<quint16>( newValue );
    memcpy( pointBuffer + 12, &newValueShort, sizeof( qint16 ) );
  }
  else if ( attributeName == QLatin1String( "ReturnNumber" ) )  // bits 0-3
  {
    uchar newByteValue = static_cast<uchar>( newValue ) & 0xf;
    pointBuffer[14] = static_cast<char>( ( pointBuffer[14] & 0xf0 ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "NumberOfReturns" ) )  // bits 4-7
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0xf ) << 4;
    pointBuffer[14] = static_cast<char>( ( pointBuffer[14] & 0xf ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "Synthetic" ) )  // bit 0
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 );
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xfe ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "KeyPoint" ) )  // bit 1
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 ) << 1;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xfd ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "Withheld" ) )  // bit 2
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 ) << 2;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xfb ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "Overlap" ) )  // bit 3
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 ) << 3;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xf7 ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "ScannerChannel" ) )  // bits 4-5
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x3 ) << 4;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xcf ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "ScanDirectionFlag" ) )  // bit 6
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 ) << 6;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0xbf ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "EdgeOfFlightLine" ) )  // bit 7
  {
    uchar newByteValue = ( static_cast<uchar>( newValue ) & 0x1 ) << 7;
    pointBuffer[15] = static_cast<char>( ( pointBuffer[15] & 0x7f ) | newByteValue );
  }
  else if ( attributeName == QLatin1String( "Classification" ) )  // unsigned char
  {
    pointBuffer[16] = static_cast<char>( static_cast<uchar>( newValue ) );
  }
  else if ( attributeName == QLatin1String( "UserData" ) )  // unsigned char
  {
    pointBuffer[17] = static_cast<char>( static_cast<uchar>( newValue ) );
  }
  else if ( attributeName == QLatin1String( "ScanAngleRank" ) )  // short
  {
    qint16 newValueShort = static_cast<qint16>( std::round( newValue / 0.006 ) );  // copc stores angle in 0.006deg increments
    memcpy( pointBuffer + 18, &newValueShort, sizeof( qint16 ) );
  }
  else if ( attributeName == QLatin1String( "PointSourceId" ) )  // unsigned short
  {
    quint16 newValueShort = static_cast<quint16>( newValue );
    memcpy( pointBuffer + 20, &newValueShort, sizeof( quint16 ) );
  }
  else if ( attributeName == QLatin1String( "GpsTime" ) )  // double
  {
    memcpy( pointBuffer + 22, &newValue, sizeof( double ) );
  }
  else if ( pointFormat == 7 || pointFormat == 8 )
  {
    if ( attributeName == QLatin1String( "Red" ) )  // unsigned short
    {
      quint16 newValueShort = static_cast<quint16>( newValue );
      memcpy( pointBuffer + 30, &newValueShort, sizeof( quint16 ) );
    }
    else if ( attributeName == QLatin1String( "Green" ) )  // unsigned short
    {
      quint16 newValueShort = static_cast<quint16>( newValue );
      memcpy( pointBuffer + 32, &newValueShort, sizeof( quint16 ) );
    }
    else if ( attributeName == QLatin1String( "Blue" ) )  // unsigned short
    {
      quint16 newValueShort = static_cast<quint16>( newValue );
      memcpy( pointBuffer + 34, &newValueShort, sizeof( quint16 ) );
    }
    else if ( pointFormat == 8 )
    {
      if ( attributeName == QLatin1String( "Infrared" ) )  // unsigned short
      {
        quint16 newValueShort = static_cast<quint16>( newValue );
        memcpy( pointBuffer + 36, &newValueShort, sizeof( quint16 ) );
      }
    }
  }
}
 
 
QByteArray QgsPointCloudLayerEditUtils::updateChunkValues( QgsCopcPointCloudIndex *copcIndex, const QByteArray &chunkData, const QgsPointCloudAttribute &attribute, const QgsPointCloudNodeId &n, const QHash<int, double> &pointValues, std::optional<double> newValue )
{
  Q_ASSERT( copcIndex->mHierarchy.contains( n ) );
  Q_ASSERT( copcIndex->mHierarchyNodePos.contains( n ) );
 
  int pointCount = copcIndex->mHierarchy[n];
 
  lazperf::header14 header = copcIndex->mLazInfo->header();
 
  lazperf::reader::chunk_decompressor decompressor( header.pointFormat(), header.ebCount(), chunkData.constData() );
  lazperf::writer::chunk_compressor compressor( header.pointFormat(), header.ebCount() );
 
  std::unique_ptr<char []> decodedData( new char[ header.point_record_length ] );
 
  // only PDRF 6/7/8 is allowed by COPC
  Q_ASSERT( header.pointFormat() == 6 || header.pointFormat() == 7 || header.pointFormat() == 8 );
 
  QString attributeName = attribute.name();
 
  for ( int i = 0 ; i < pointCount; ++i )
  {
    decompressor.decompress( decodedData.get() );
    char *buf = decodedData.get();
 
    if ( pointValues.contains( i ) )
    {
      // TODO: support for extrabytes attributes
      updatePoint( buf, header.point_format_id, attributeName, newValue ? *newValue : pointValues[i] );
    }
 
    compressor.compress( decodedData.get() );
  }
 
  std::vector<unsigned char> data = compressor.done();
  return QByteArray( ( const char * ) data.data(), ( int ) data.size() ); // QByteArray makes a deep copy
}
 
bool QgsPointCloudLayerEditUtils::isAttributeValueValid( const QgsPointCloudAttribute &attribute, double value )
{
  const QString name = attribute.name().toUpper();
 
  if ( name == QLatin1String( "INTENSITY" ) )
    return value >= 0 && value <= 65535;
  if ( name == QLatin1String( "RETURNNUMBER" ) )
    return value >= 0 && value <= 15;
  if ( name == QLatin1String( "NUMBEROFRETURNS" ) )
    return value >= 0 && value <= 15;
  if ( name == QLatin1String( "SCANNERCHANNEL" ) )
    return value >= 0 && value <= 3;
  if ( name == QLatin1String( "SCANDIRECTIONFLAG" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "EDGEOFFLIGHTLINE" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "CLASSIFICATION" ) )
    return value >= 0 && value <= 255;
  if ( name == QLatin1String( "USERDATA" ) )
    return value >= 0 && value <= 255;
  if ( name == QLatin1String( "SCANANGLERANK" ) )
    return value >= -180 && value <= 180;
  if ( name == QLatin1String( "POINTSOURCEID" ) )
    return value >= 0 && value <= 65535;
  if ( name == QLatin1String( "GPSTIME" ) )
    return value >= 0;
  if ( name == QLatin1String( "SYNTHETIC" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "KEYPOINT" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "WITHHELD" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "OVERLAP" ) )
    return value >= 0 && value <= 1;
  if ( name == QLatin1String( "RED" ) )
    return value >= 0 && value <= 65535;
  if ( name == QLatin1String( "GREEN" ) )
    return value >= 0 && value <= 65535;
  if ( name == QLatin1String( "BLUE" ) )
    return value >= 0 && value <= 65535;
  if ( name == QLatin1String( "INFRARED" ) )
    return value >= 0 && value <= 65535;
 
  return true;
}