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/*
* Copyright (C) 2005-2020 Centre National d'Etudes Spatiales (CNES)
*
* This file is part of Orfeo Toolbox
*
* https://www.orfeo-toolbox.org/
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// Instead of using \doxygen{otb}{VectorData} to apply projections as
// explained in \ref{sec:VectorDataProjection}, we can also \emph{directly} work
// on OGR data types thanks to \doxygen{otb}{GeometriesProjectionFilter}.
//
// This example demonstrates how to proceed with this alternative set of vector
// data types.
#include "otbGeometriesProjectionFilter.h"
#include "otbGeometriesSet.h"
#include "otbImage.h"
#include "otbImageFileReader.h"
int main(int argc, char* argv[])
{
if (argc < 4)
{
std::cerr << argv[0] << " <input vector filename> <input image name> <output vector filename>\n";
return EXIT_FAILURE;
}
// Declare the geometries type that you would like to use in your
// application. Unlike \doxygen{otb}{VectorData}, \doxygen{otb}{GeometriesSet}
// is a single type for any kind of geometries set (OGR data source, or OGR
// layer).
using InputGeometriesType = otb::GeometriesSet;
using OutputGeometriesType = otb::GeometriesSet;
// First, declare and instantiate the data source
// \subdoxygen{otb}{ogr}{DataSource}. Then, encapsulate this data source into
// a \doxygen{otb}{GeometriesSet}.
otb::ogr::DataSource::Pointer input = otb::ogr::DataSource::New(argv[1], otb::ogr::DataSource::Modes::Read);
InputGeometriesType::Pointer in_set = InputGeometriesType::New(input);
// We need the image only to retrieve its projection information,
// i.e. map projection or sensor model parameters. Hence, the image
// pixels won't be read, only the header information using the
// \code{UpdateOutputInformation()} method.
using ImageType = otb::Image<unsigned short int, 2>;
using ImageReaderType = otb::ImageFileReader<ImageType>;
ImageReaderType::Pointer imageReader = ImageReaderType::New();
imageReader->SetFileName(argv[2]);
imageReader->UpdateOutputInformation();
// The \doxygen{otb}{GeometriesProjectionFilter} will do the work of
// converting the geometries coordinates. It is usually a good idea
// to use it when you design applications reading or saving vector
// data.
using GeometriesFilterType = otb::GeometriesProjectionFilter;
GeometriesFilterType::Pointer filter = GeometriesFilterType::New();
// Information concerning the original projection of the vector data
// will be automatically retrieved from the metadata. Nothing else
// is needed from you:
filter->SetInput(in_set);
// Information about the target projection is retrieved directly from
// the image:
// necessary for sensors
filter->SetOutputKeywordList(imageReader->GetOutput()->GetImageKeywordlist());
// necessary for sensors
filter->SetOutputOrigin(imageReader->GetOutput()->GetOrigin());
// necessary for sensors
filter->SetOutputSpacing(imageReader->GetOutput()->GetSignedSpacing());
// ~ wkt
filter->SetOutputProjectionRef(imageReader->GetOutput()->GetProjectionRef());
// Finally, the result is saved into a new vector file.
// Unlike other OTB filters, \doxygen{otb}{GeometriesProjectionFilter} expects
// to be given a valid output geometries set where to store the result of its
// processing -- otherwise the result will be an in-memory data source, and
// not stored in a file nor a data base.
//
// Then, the processing is started by calling \code{Update()}. The actual
// serialization of the results is guaranteed to be completed when the output
// geometries set object goes out of scope, or when \code{SyncToDisk} is
// called.
otb::ogr::DataSource::Pointer output = otb::ogr::DataSource::New(argv[3], otb::ogr::DataSource::Modes::Update_LayerCreateOnly);
OutputGeometriesType::Pointer out_set = OutputGeometriesType::New(output);
filter->SetOutput(out_set);
filter->Update();
// Once again, it is worth noting that none of this code is specific to the
// vector data format. Whether you pass a shapefile, or a KML file, the
// correct driver will be automatically instantiated.
return EXIT_SUCCESS;
}
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