Spatial relationships | ArcGIS Maps SDK for Qt

View on GitHub

Sample viewer app

Determine spatial relationships between two geometries.

Use case

In case of a natural disaster, emergency services can represent the affected areas using polygons. By determining the spatial relationships between these and any other existing features such as populated areas, infrastructure, or natural resources, it is possible to quickly determine which of the existing features might be affected or is in further danger, helping to assess risk and define further action.

How to use the sample

Select one of the three graphics. The tree view will list the relationships the selected graphic has to the other graphic geometries.

How it works

Get the geometry from two different graphics. In this example the geometry of the selected graphic is compared to the geometry of each unselected graphic.
Use the methods in GeometryEngine to check the relationship between the geometries, e.g. contains, disjoint, intersects, etc. If the method returns true, the relationship exists.

Relevant API

Geometry
GeometryEngine
GeometryEngine::contains
GeometryEngine::crosses
GeometryEngine::disjoint
GeometryEngine::intersects
GeometryEngine::overlaps
GeometryEngine::touches
GeometryEngine::within
GeometryType
Graphic
Point
Polygon
Polyline

Sample Code

SpatialRelationships.cpp

SpatialRelationships.h

SpatialRelationships.qml

main.cpp

// [WriteFile Name=SpatialRelationships, Category=Geometry]
// [Legal]
// Copyright 2018 Esri.
//
// 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.
// [Legal]

#ifdef PCH_BUILD
#include "pch.hpp"
#endif // PCH_BUILD

// sample headers
#include "SpatialRelationships.h"

// ArcGIS Maps SDK headers
#include "GeometryEngine.h"
#include "Graphic.h"
#include "GraphicListModel.h"
#include "GraphicsOverlay.h"
#include "GraphicsOverlayListModel.h"
#include "IdentifyGraphicsOverlayResult.h"
#include "Map.h"
#include "MapQuickView.h"
#include "MapTypes.h"
#include "Point.h"
#include "Polygon.h"
#include "PolygonBuilder.h"
#include "Polyline.h"
#include "PolylineBuilder.h"
#include "SelectionProperties.h"
#include "SimpleFillSymbol.h"
#include "SimpleLineSymbol.h"
#include "SimpleMarkerSymbol.h"
#include "SpatialReference.h"
#include "SymbolTypes.h"

// Qt headers
#include <QFuture>
#include <QStringList>
#include <QUuid>

// STL headers
#include <memory>

using namespace Esri::ArcGISRuntime;

SpatialRelationships::SpatialRelationships(QQuickItem* parent /* = nullptr */):
  QQuickItem(parent)
{
}

void SpatialRelationships::init()
{
  // Register the map view for QML
  qmlRegisterType<MapQuickView>("Esri.Samples", 1, 0, "MapView");
  qmlRegisterType<SpatialRelationships>("Esri.Samples", 1, 0, "SpatialRelationshipsSample");
}

void SpatialRelationships::componentComplete()
{
  QQuickItem::componentComplete();

  // find QML MapView component
  m_mapView = findChild<MapQuickView*>("mapView");
  m_mapView->setSelectionProperties(SelectionProperties(QColor(Qt::yellow)));

  // Create a map using the topographic basemap
  m_map = new Map(BasemapStyle::ArcGISTopographic, this);

  // Set map to map view
  m_mapView->setMap(m_map);

  // Create GraphicsOverlay
  m_graphicsOverlay = new GraphicsOverlay(this);
  m_mapView->graphicsOverlays()->append(m_graphicsOverlay);

  // Add Graphics
  addGraphics();

  // Set viewpoint
  m_mapView->setViewpointCenterAsync(geometry_cast<Point>(m_pointGraphic->geometry()), 200000000);

  // connect signals
  connectSignals();
}

void SpatialRelationships::addGraphics()
{
  addPolygonGraphic();
  addPolylineGraphic();
  addPointGraphic();
}

void SpatialRelationships::addPolygonGraphic()
{
  // create polygon geometry
  PolygonBuilder polyBuilder(SpatialReference::webMercator());
  polyBuilder.addPoint(-5991501.677830, 5599295.131468);
  polyBuilder.addPoint(-6928550.398185, 2087936.739807);
  polyBuilder.addPoint(-3149463.800709, 1840803.011362);
  polyBuilder.addPoint(-1563689.043184, 3714900.452072);
  polyBuilder.addPoint(-3180355.516764, 5619889.608838);
  Polygon geom = polyBuilder.toPolygon();

  // create symbol
  SimpleLineSymbol* outline = new SimpleLineSymbol(SimpleLineSymbolStyle::Solid, QColor("green"), 2.0f /*width*/, this);
  SimpleFillSymbol* sfs = new SimpleFillSymbol(SimpleFillSymbolStyle::ForwardDiagonal, QColor("green"), outline, this);

  // create graphic
  m_polygonGraphic = new Graphic(geom, sfs);
  m_graphicsOverlay->graphics()->append(m_polygonGraphic);
}

void SpatialRelationships::addPolylineGraphic()
{
  // create poyline geometry
  PolylineBuilder polyBuilder(SpatialReference::webMercator());
  polyBuilder.addPoint(-4354240.726880, -609939.795721);
  polyBuilder.addPoint(-3427489.245210, 2139422.933233);
  polyBuilder.addPoint(-2109442.693501, 4301843.057130);
  polyBuilder.addPoint(-1810822.771630, 7205664.366363);
  Polyline geom = polyBuilder.toPolyline();

  // create symbol
  SimpleLineSymbol* sls = new SimpleLineSymbol(SimpleLineSymbolStyle::Dash, QColor("red"), 4.0f /*width*/, this);

  // create graphic
  m_polylineGraphic = new Graphic(geom, sls);
  m_graphicsOverlay->graphics()->append(m_polylineGraphic);
}

void SpatialRelationships::addPointGraphic()
{
  // Create point geometry
  Point geom(-4487263.495911, 3699176.480377, SpatialReference::webMercator());

  // create symbol
  SimpleMarkerSymbol* sms = new SimpleMarkerSymbol(SimpleMarkerSymbolStyle::Circle, QColor("blue"), 10.0f /*size*/, this);

  // create graphic
  m_pointGraphic = new Graphic(geom, sms, this);
  m_graphicsOverlay->graphics()->append(m_pointGraphic);
}

void SpatialRelationships::connectSignals()
{
  connect(m_mapView, &MapQuickView::mouseClicked, this, [this](QMouseEvent& mouseEvent)
  {
    // identify graphics
    m_mapView->identifyGraphicsOverlayAsync(m_graphicsOverlay, mouseEvent.position(), 1.0 /*tolerance*/, false /*returnPopupsOnly*/).then(this,
    [this](IdentifyGraphicsOverlayResult* rawResult)
    {
      // Delete rawReslt when we leave scope.
      auto result = std::unique_ptr<IdentifyGraphicsOverlayResult>(rawResult);

      const QList<Graphic*> identifiedGraphics = result->graphics();
      if (identifiedGraphics.isEmpty())
        return;

      // get the first identified graphic
      Graphic* graphic = identifiedGraphics.at(0);

      // select the graphic
      m_graphicsOverlay->clearSelection();
      graphic->setSelected(true);

      // get the geometry
      const Geometry selectedGeometry = graphic->geometry();
      const GeometryType selectedGeometryType = selectedGeometry.geometryType();

      // reset the output text
      m_pointRelationships = "";
      m_polylineRelationships = "";
      m_polygonRelationships = "";

      // populate the view with the spatial relationships the selected graphic has to the other graphics
      // ignore testing relationships between the geometry and itself
      if (selectedGeometryType != GeometryType::Point)
      {
        const QString pointRelationships = getSpatialRelationships(selectedGeometry, m_pointGraphic->geometry()).join(",");
        m_pointRelationships = QString("Point: %1").arg(pointRelationships);
      }
      if (selectedGeometryType != GeometryType::Polyline)
      {
        const QString polylineRelationships = getSpatialRelationships(selectedGeometry, m_polylineGraphic->geometry()).join(",");
        m_polylineRelationships = QString("Polyline: %1").arg(polylineRelationships);
      }
      if (selectedGeometryType != GeometryType::Polygon)
      {
        const QString polygonRelationships = getSpatialRelationships(selectedGeometry, m_polygonGraphic->geometry()).join(",");
        m_polygonRelationships = QString("Polygon: %1").arg(polygonRelationships);
      }

      emit relationshipsChanged();
    });

  });
}

// function to return list of relaionships
QStringList SpatialRelationships::getSpatialRelationships(const Geometry& geom1, const Geometry& geom2)
{
  QStringList relationships;
  if (GeometryEngine::crosses(geom1, geom2))
    relationships.append("CROSSES");
  if (GeometryEngine::contains(geom1, geom2))
    relationships.append("CONTAINS");
  if (GeometryEngine::disjoint(geom1, geom2))
    relationships.append("DISJOINT");
  if (GeometryEngine::intersects(geom1, geom2))
    relationships.append("INTERSECTS");
  if (GeometryEngine::overlaps(geom1, geom2))
    relationships.append("OVERLAPS");
  if (GeometryEngine::touches(geom1, geom2))
    relationships.append("TOUCHES");
  if (GeometryEngine::within(geom1, geom2))
    relationships.append("WITHIN");
  return relationships;
}

// [WriteFile Name=SpatialRelationships, Category=Geometry]
// [Legal]
// Copyright 2018 Esri.
//
// 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.
// [Legal]

#ifndef SPATIALRELATIONSHIPS_H
#define SPATIALRELATIONSHIPS_H

// ArcGIS Maps SDK headers
#include "Geometry.h"

// Qt headers
#include <QQuickItem>

namespace Esri::ArcGISRuntime
{
class Map;
class MapQuickView;
class Graphic;
class GraphicsOverlay;
}

class SpatialRelationships : public QQuickItem
{
  Q_OBJECT

  Q_PROPERTY(QString pointRelationships MEMBER m_pointRelationships NOTIFY relationshipsChanged)
  Q_PROPERTY(QString polygonRelationships MEMBER m_polygonRelationships NOTIFY relationshipsChanged)
  Q_PROPERTY(QString polylineRelationships MEMBER m_polylineRelationships NOTIFY relationshipsChanged)

public:
  explicit SpatialRelationships(QQuickItem* parent = nullptr);
  ~SpatialRelationships() override = default;

  void componentComplete() override;
  static void init();

signals:
  void relationshipsChanged();

private:
  Esri::ArcGISRuntime::Map* m_map = nullptr;
  Esri::ArcGISRuntime::MapQuickView* m_mapView = nullptr;
  Esri::ArcGISRuntime::GraphicsOverlay* m_graphicsOverlay = nullptr;
  Esri::ArcGISRuntime::Graphic* m_pointGraphic = nullptr;
  Esri::ArcGISRuntime::Graphic* m_polylineGraphic = nullptr;
  Esri::ArcGISRuntime::Graphic* m_polygonGraphic = nullptr;
  QString m_pointRelationships;
  QString m_polygonRelationships;
  QString m_polylineRelationships;

  void addGraphics();
  void addPointGraphic();
  void addPolygonGraphic();
  void addPolylineGraphic();
  void connectSignals();
  QStringList getSpatialRelationships(const Esri::ArcGISRuntime::Geometry& geom1, const Esri::ArcGISRuntime::Geometry& geom2);
};

#endif // SPATIALRELATIONSHIPS_H

// [WriteFile Name=SpatialRelationships, Category=Geometry]
// [Legal]
// Copyright 2018 Esri.
//
// 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.
// [Legal]

import QtQuick
import QtQuick.Window
import QtQuick.Controls
import Esri.Samples

SpatialRelationshipsSample {
    id: rootRectangle
    clip: true
    width: 800
    height: 600



    // add a mapView component
    MapView {
        anchors.fill: parent
        objectName: "mapView"

        Component.onCompleted: {
            // Set the focus on MapView to initially enable keyboard navigation
            forceActiveFocus();
        }
    }

    Rectangle {
        anchors {
            fill: relationshipColumn
            margins: -10
        }
        opacity: 0.85
        radius: 5
        color: "#e2e2e2"
        border {
            color: "darkgray"
            width: 1
        }
    }

    Column {
        id: relationshipColumn
        anchors {
            left: parent.left
            top: parent.top
            margins: 15
        }
        spacing: 5

        Text {
            text: "Relationships:"
            font {
                pixelSize: 16
                bold: true
                family: "helvetica"
            }
        }

        Text {
            id: pointText
            visible: text.length > 0
            font.family: "helvetica"
            text: pointRelationships
        }

        Text {
            id: lineText
            visible: text.length > 0
            font.family: "helvetica"
            text: polylineRelationships
        }

        Text {
            id: polygonText
            visible: text.length > 0
            font.family: "helvetica"
            text: polygonRelationships
        }
    }
}

// [Legal]
// Copyright 2018 Esri.
//
// 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.
// [Legal]

// sample headers
#include "SpatialRelationships.h"

// ArcGIS Maps SDK headers
#include "ArcGISRuntimeEnvironment.h"

// Qt headers
#include <QCommandLineParser>
#include <QDir>
#include <QGuiApplication>
#include <QQmlEngine>
#include <QQuickView>

// Platform specific headers
#ifdef Q_OS_WIN
#include <Windows.h>
#endif

#define STRINGIZE(x) #x
#define QUOTE(x) STRINGIZE(x)

int main(int argc, char *argv[])
{
  Esri::ArcGISRuntime::ArcGISRuntimeEnvironment::setUseLegacyAuthentication(false);
  QGuiApplication app(argc, argv);
  app.setApplicationName(QString("SpatialRelationships"));

  // Use of ArcGIS location services, such as basemap styles, geocoding, and routing services,
  // requires an access token. For more information see
  // https://links.esri.com/arcgis-runtime-security-auth.

  // The following methods grant an access token:

  // 1. User authentication: Grants a temporary access token associated with a user's ArcGIS account.
  // To generate a token, a user logs in to the app with an ArcGIS account that is part of an
  // organization in ArcGIS Online or ArcGIS Enterprise.

  // 2. API key authentication: Get a long-lived access token that gives your application access to
  // ArcGIS location services. Go to the tutorial at https://links.esri.com/create-an-api-key.
  // Copy the API Key access token.

  const QString accessToken = QString("");

  if (accessToken.isEmpty())
  {
      qWarning() << "Use of ArcGIS location services, such as the basemap styles service, requires" <<
                    "you to authenticate with an ArcGIS account or set the API Key property.";
  }
  else
  {
      Esri::ArcGISRuntime::ArcGISRuntimeEnvironment::setApiKey(accessToken);
  }

  // Initialize the sample
  SpatialRelationships::init();

  // Initialize application view
  QQuickView view;
  view.setResizeMode(QQuickView::SizeRootObjectToView);

  QString arcGISRuntimeImportPath = QUOTE(ARCGIS_RUNTIME_IMPORT_PATH);

#if defined(LINUX_PLATFORM_REPLACEMENT)
  // on some linux platforms the string 'linux' is replaced with 1
  // fix the replacement paths which were created
  QString replaceString = QUOTE(LINUX_PLATFORM_REPLACEMENT);
  arcGISRuntimeImportPath = arcGISRuntimeImportPath.replace(replaceString, "linux", Qt::CaseSensitive);
#endif

  // Add the import Path
  view.engine()->addImportPath(QDir(QCoreApplication::applicationDirPath()).filePath("qml"));
  // Add the Runtime and Extras path
  view.engine()->addImportPath(arcGISRuntimeImportPath);

  // Set the source
  view.setSource(QUrl("qrc:/Samples/Geometry/SpatialRelationships/SpatialRelationships.qml"));

  view.show();

  return app.exec();
}

Use case

How to use the sample

How it works

Relevant API

Tags

Sample Code