Edit the values of a KML ground overlay.
Use case
KML ground overlays are used for showing aerial imagery, symbology, or other images draped over a scene. Changing the geometry, rotation, and other attributes of a ground overlay after it has been loaded allows for live editing. For example, editing the geometry and opacity of a historical image draped over present day satellite imagery makes it possible to view change over time.
How to use the sample
Use the slider to adjust the opacity of the ground overlay.
How it works
- Create an
Envelope
defining the geometry of the overlay. - Create a
KmlIcon
using aUrl
linking to an image. - Create a
KmlGroundOverlay
using the envelope and icon. - Set the value of
KmlGroundOverlay::rotation
. - Create a
KmlDataset
using the ground overlay. - Create a
KmlLayer
using the dataset. - Add the KML layer to the scene.
- Listen for changes to the opacity slider and change the
KmlGroundOverlay::color
value appropriately.
Relevant API
- KmlDataset
- KmlGroundOverlay
- KmlIcon
- KmlLayer
About the data
The image used in this sample is an aerial view of the campus of the University of Oregon. This imagery was taken in 1944 by the U.S. Army Corps of Engineers. It is publicly available as Online Aerial Imagery hosted by Oregon University Library. It is also available as a Portal item on ArcGIS Online as University of Oregon Campus Aerial Imagery - 1944.
Tags
imagery, keyhole, KML, KMZ, OGC
Sample Code
// [WriteFile Name=EditKmlGroundOverlay, Category=EditData]
// [Legal]
// Copyright 2019 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
#include "EditKmlGroundOverlay.h"
#include "Scene.h"
#include "SceneQuickView.h"
#include "KmlLayer.h"
#include "KmlGroundOverlay.h"
#include "KmlDataset.h"
#include "KmlIcon.h"
#include "Envelope.h"
#include "Camera.h"
#include <QDir>
#include <QtCore/qglobal.h>
#ifdef Q_OS_IOS
#include <QStandardPaths>
#endif // Q_OS_IOS
using namespace Esri::ArcGISRuntime;
// helper method to get cross platform data path
namespace
{
QString defaultDataPath()
{
QString dataPath;
#ifdef Q_OS_ANDROID
dataPath = "/sdcard";
#elif defined Q_OS_IOS
dataPath = QStandardPaths::writableLocation(QStandardPaths::DocumentsLocation);
#else
dataPath = QDir::homePath();
#endif
return dataPath;
}
} // namespace
EditKmlGroundOverlay::EditKmlGroundOverlay(QObject* parent /* = nullptr */):
QObject(parent),
m_scene(new Scene(BasemapStyle::ArcGISImageryStandard, this))
{
// Create Geometry
const Envelope env(-123.066227926904, 44.04736963555683,
-123.0796942287304, 44.03878298600624,
SpatialReference(4326));
// Create KML Icon
KmlIcon* kmlIcon = new KmlIcon(QUrl(defaultDataPath() + "/ArcGIS/Runtime/Data/raster/1944.jpg"), this);
// Create Ground Overlay
m_groundOverlay = new KmlGroundOverlay(env, kmlIcon, this);
m_groundOverlay->setRotation(-3.046024799346924);
// Create Dataset
KmlDataset* kmlDataset = new KmlDataset(m_groundOverlay, this);
// Create Layer
KmlLayer* kmlLayer = new KmlLayer(kmlDataset, this);
// Connect to know when the layer loads
connect(kmlLayer, &KmlLayer::doneLoading, this, [this, env](Error e)
{
if (!e.isEmpty() || !m_sceneView)
return;
const Camera camera(env.center(), 1250, 45, 60, 0);
m_sceneView->setViewpointCamera(camera);
});
m_scene->operationalLayers()->append(kmlLayer);
}
EditKmlGroundOverlay::~EditKmlGroundOverlay() = default;
void EditKmlGroundOverlay::init()
{
// Register classes for QML
qmlRegisterType<SceneQuickView>("Esri.Samples", 1, 0, "SceneView");
qmlRegisterType<EditKmlGroundOverlay>("Esri.Samples", 1, 0, "EditKmlGroundOverlaySample");
}
void EditKmlGroundOverlay::setOpacity(int opacity)
{
if (!m_groundOverlay)
return;
m_groundOverlay->setColor(QColor(0, 0, 0, opacity));
}
SceneQuickView* EditKmlGroundOverlay::sceneView() const
{
return m_sceneView;
}
// Set the view (created in QML)
void EditKmlGroundOverlay::setSceneView(SceneQuickView* sceneView)
{
if (!sceneView || sceneView == m_sceneView)
return;
m_sceneView = sceneView;
m_sceneView->setArcGISScene(m_scene);
emit sceneViewChanged();
}