Analyze the exploratory viewshed for a camera showing the visible and obstructed areas from an observer’s vantage point.

Use case
An exploratory viewshed analysis is a type of visual analysis you can perform at the current rendered resolution of a scene. The exploratory viewshed aims to answer the question ‘What can I see from a given location?’. The output is an overlay with two different colors - one representing the visible areas (green) and the other representing the obstructed areas (red).
Note: This analysis is a form of “exploratory analysis”, which means the results are calculated on the current scale of the data, and the results are generated very quickly but not persisted. If persisted analysis performed at the full resolution of the data is required, consider using a ViewshedFunction to perform a viewshed calculation instead.
How to use the sample
The sample will start with an exploratory viewshed created from the initial camera location, so only the visible (green) portion of the exploratory viewshed will be visible. Move around the scene to see the obstructed (red) portions. Click the ‘Update from Camera’ button to update the exploratory viewshed to the current camera position.
How it works
- Get the current camera from the scene with
SceneView::currentViewpointCamera. - Create an
ExploratoryLocationViewshed, passing in theCameraand a min/max distance. - Update the viewshed from a camera.
Relevant API
- AnalysisOverlay
- ArcGISScene
- ArcGISTiledElevationSource
- Camera
- ExploratoryLocationViewshed
- IntegratedMeshLayer
- SceneView
About the data
The scene shows an integrated mesh layer of Girona, Spain with the World Elevation source image service both hosted on ArcGIS Online.
Tags
3D, exploratory viewshed, integrated mesh, Scene, visibility analysis
Sample Code
// [WriteFile Name=ShowExploratoryViewshedFromCameraInScene, Category=Analysis]// [Legal]// Copyright 2017 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 "ShowExploratoryViewshedFromCameraInScene.h"
// ArcGIS Maps SDK headers#include "AnalysisListModel.h"#include "AnalysisOverlay.h"#include "AnalysisOverlayListModel.h"#include "ArcGISTiledElevationSource.h"#include "Camera.h"#include "ElevationSourceListModel.h"#include "ExploratoryLocationViewshed.h"#include "IntegratedMeshLayer.h"#include "LayerListModel.h"#include "MapTypes.h"#include "Point.h"#include "Scene.h"#include "SceneQuickView.h"#include "SpatialReference.h"#include "Surface.h"#include "Viewpoint.h"
using namespace Esri::ArcGISRuntime;
ShowExploratoryViewshedFromCameraInScene::ShowExploratoryViewshedFromCameraInScene(QQuickItem* parent /* = nullptr */) : QQuickItem(parent){}
void ShowExploratoryViewshedFromCameraInScene::init(){ // Register classes for QML qmlRegisterType<SceneQuickView>("Esri.Samples", 1, 0, "SceneView"); qmlRegisterType<ShowExploratoryViewshedFromCameraInScene>("Esri.Samples", 1, 0, "ShowExploratoryViewshedFromCameraInSceneSample");}
void ShowExploratoryViewshedFromCameraInScene::componentComplete(){ QQuickItem::componentComplete();
// Create a scene m_sceneView = findChild<SceneQuickView*>("sceneView"); m_scene = new Scene(BasemapStyle::ArcGISImageryStandard, this);
// Set a base surface Surface* surface = new Surface(this); surface->elevationSources()->append( new ArcGISTiledElevationSource(QUrl("https://elevation3d.arcgis.com/arcgis/rest/services/WorldElevation3D/Terrain3D/ImageServer"), this)); m_scene->setBaseSurface(surface);
// Create and add the Girona, Spain integrated mesh layer IntegratedMeshLayer* gironaMeshLayer = new IntegratedMeshLayer(QUrl("https://tiles.arcgis.com/tiles/z2tnIkrLQ2BRzr6P/arcgis/rest/services/Girona_Spain/SceneServer"), this); m_scene->operationalLayers()->append(gironaMeshLayer);
// Add an AnalysisOverlay to display the viewshed analysis result m_analysisOverlay = new AnalysisOverlay(this); m_sceneView->analysisOverlays()->append(m_analysisOverlay);
// Set initial viewpoint setInitialViewpoint();
// Add the Scene to the Sceneview m_sceneView->setArcGISScene(m_scene);}
void ShowExploratoryViewshedFromCameraInScene::calculateViewshed(){ if (!m_viewshed) { // Create the viewshed const double minDistance = 1; const double maxDistance = 1000; m_viewshed = new ExploratoryLocationViewshed(m_sceneView->currentViewpointCamera(), minDistance, maxDistance, this);
// display the frustum m_viewshed->setFrustumOutlineVisible(true);
// Add the viewshed to the overlay m_analysisOverlay->analyses()->append(m_viewshed); } else { m_viewshed->updateFromCamera(m_sceneView->currentViewpointCamera()); }}
void ShowExploratoryViewshedFromCameraInScene::setInitialViewpoint(){ const double x_longitude = 2.82691; const double y_latitude = 41.985; const double z_altitude = 124.987; Point pt(x_longitude, y_latitude, z_altitude, SpatialReference(4326));
const double heading = 332.131; const double pitch = 82.4732; const double roll = 0; Camera camera(pt, heading, pitch, roll);
Viewpoint initViewpoint(pt, camera); m_scene->setInitialViewpoint(initViewpoint);}// [WriteFile Name=ShowExploratoryViewshedFromCameraInScene, Category=Analysis]// [Legal]// Copyright 2017 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 ShowExploratoryViewshedFromCameraInScene_H#define ShowExploratoryViewshedFromCameraInScene_H
// Qt headers#include <QQuickItem>
namespace Esri::ArcGISRuntime{ class Scene; class SceneQuickView; class AnalysisOverlay; class ExploratoryLocationViewshed;} // namespace Esri::ArcGISRuntime
class ShowExploratoryViewshedFromCameraInScene : public QQuickItem{ Q_OBJECT
public: explicit ShowExploratoryViewshedFromCameraInScene(QQuickItem* parent = nullptr); ~ShowExploratoryViewshedFromCameraInScene() override = default;
void componentComplete() override; static void init(); Q_INVOKABLE void calculateViewshed();
private: void setInitialViewpoint();
Esri::ArcGISRuntime::Scene* m_scene = nullptr; Esri::ArcGISRuntime::SceneQuickView* m_sceneView = nullptr; Esri::ArcGISRuntime::AnalysisOverlay* m_analysisOverlay = nullptr; Esri::ArcGISRuntime::ExploratoryLocationViewshed* m_viewshed = nullptr;};
#endif // ShowExploratoryViewshedFromCameraInScene_H// [WriteFile Name=ShowExploratoryViewshedFromCameraInScene, Category=Analysis]// [Legal]// Copyright 2017 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 QtQuickimport QtQuick.Controlsimport Esri.Samples
ShowExploratoryViewshedFromCameraInSceneSample { id: rootRectangle clip: true width: 800 height: 600
SceneView { id: view objectName: "sceneView" anchors.fill: parent
Component.onCompleted: { // Set the focus on SceneView to initially enable keyboard navigation forceActiveFocus(); }
Button { anchors { horizontalCenter: parent.horizontalCenter bottom: view.attributionTop margins: 5 } text: qsTr("Calculate Viewshed") onClicked: calculateViewshed(); } }}// [WriteFile Name=ShowExploratoryViewshedFromCameraInScene, Category=Analysis]// [Legal]// Copyright 2017 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 "ShowExploratoryViewshedFromCameraInScene.h"
// ArcGIS Maps SDK headers#include "ArcGISRuntimeEnvironment.h"
// Qt headers#include <QCommandLineParser>#include <QDir>#include <QGuiApplication>#include <QQmlEngine>#include <QQuickView>#include <QSurfaceFormat>
// 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[]){#if defined(Q_OS_LINUX) && !defined(Q_OS_ANDROID) // Linux requires 3.2 OpenGL Context // in order to instance 3D symbols QSurfaceFormat fmt = QSurfaceFormat::defaultFormat(); fmt.setVersion(3, 2); QSurfaceFormat::setDefaultFormat(fmt);#endif
QGuiApplication app(argc, argv); app.setApplicationName(QString("ShowExploratoryViewshedFromCameraInScene"));
// 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 ShowExploratoryViewshedFromCameraInScene::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/Analysis/ShowExploratoryViewshedFromCameraInScene/ShowExploratoryViewshedFromCameraInScene.qml"));
view.show();
return app.exec();}