Method open

LASlib/src/laswritercompatible.cpp:37–318

#include "bytestreamin_array.hpp"

BOOL LASwriterCompatibleDown::open(LASheader* header, LASwriteOpener* laswriteopener, BOOL moveCRSfromEVLRtoVLR, BOOL moveEVLRtoVLR)
{
  U32 i;
  U8 version_minor_orig = header->version_minor;

  if (header == 0)
  {
    return FALSE;
  }
  if (laswriteopener == 0)
  {
    return FALSE;
  }
  if (header->version_minor < 4) // makes only sense for LAS 1.4 input
  {
    return FALSE;
  }
  if (header->point_data_format <= 5) // but not for old point types 0, 1, 2, 3, 4, and 5
  {
    return FALSE;
  }
  else if (header->point_data_format > 10) // only the new point types 6, 7, 8, 9, and 10 are supported
  {
    return FALSE;
  }
  if (header->extended_number_of_point_records > U32_MAX) // only less than 2^32-1 points are supported
  {
    return FALSE;
  }
  this->header = header;

  // downgrade it to LAS 1.2 or LAS 1.3
  if (header->point_data_format <= 8)
  {
      if (header->version_minor >= 4) {
          // LAS 1.2 header is 148 bytes less than LAS 1.4 header
          header->header_size -= 148;
          header->offset_to_point_data -= 148;
      }
      if (header->version_minor >= 5) {
          // LAS 1.4 header is 18 bytes less than LAS 1.5 header
          header->header_size -= 18;
          header->offset_to_point_data -= 18;
      }
      header->version_minor = 2;
  }
  else
  {
      if (header->version_minor >= 4) {
          // LAS 1.3 header is 140 bytes less than LAS 1.4 header
          header->header_size -= 140;
          header->offset_to_point_data -= 140;
      }
      if (header->version_minor >= 5) {
          // LAS 1.4 header is 18 bytes less than LAS 1.5 header
          header->header_size -= 18;
          header->offset_to_point_data -= 18;
      }