1.Get all the layers present in the current globe document. Once you have a handle to the layers, loop through the layers and get all the features that are selected on the globe. See the following code example:
在当前globe文件中得到所有存在的图层。一旦你有一个图层的句柄的话,循环整个图层,得到在globe中选中的图元。看下面的代码例子。
ESRI.ArcGIS.GlobeCore.IGlobeDisplay globeDisplay
=
globe.GlobeDisplay;
ESRI.ArcGIS.Analyst3D.IScene scene
=
globeDisplay.Scene;
ESRI.ArcGIS.Carto.IEnumLayer enumLayer
=
scene.get_Layers(
null
,
true
);
2.Get a handle to the globe camera. The globe camera will be used to zoom to the extent of the selected features on the globe. See the following code example:
ESRI.ArcGIS.Analyst3D.ISceneViewer sceneViewer
=
globeDisplay.ActiveViewer;
ESRI.ArcGIS.Analyst3D.ICamera camera
=
sceneViewer.Camera;
ESRI.ArcGIS.GlobeCore.IGlobeCamera globeCamera
=
(ESRI.ArcGIS.GlobeCore.IGlobeCamera)camera;
//
Explicit cast.
3.The extent of the layers is stored in an envelope and basically defines the area you need to zoom to. Make the envelope z-aware in cases when the features in the data have z-values or are draped on an elevation surface.
图层的范围保存在一个envelope里主要定义了你要聚焦的区域。让envelope具有z属性,万了万一图元在数据中有z值,或者是覆盖在高程图层的表面。
4.Keep track of the extent of the layer where features are selected. This is important when zooming to selected point features. Getting the extent of the point features is shown in the following code example:
当聚焦到选中的点图元时,记录被选中的图元所在图层的范围是很重要的。得到点图元的范围的代码如下:
[C#]
5.Before looping through all the layers, define a Boolean to keep track of any selected features in the layers and reset the counter to get the first layer stored in IEnumLayer. See the following code example:
bool
haveFeatures
=
false
;
enumLayer.Reset();
6.To loop through the layers, use the whileloop. If no layers are present, break out of the code. See the following code example:
ESRI.ArcGIS.Carto.ILayer layer;
while
((layer
=
enumLayer.Next())
!=
null
)
...
{
if (layer == null)
break;
7.For each layer, get the feature selection set as shown in the following code example. After getting the selection set, loop through individual features using the feature cursor and store the geometry in the envelope.
对于每一个图层,得到选择图元的几何代码如下。当得到选择的几何之后,用feature cursor去循环其中的单个图元,在envelope中保存其几何形状。
ESRI.ArcGIS.Carto.IFeatureLayer featureLayer
=
(ESRI.ArcGIS.Carto.IFeatureLayer)layer;
//
Explicit cast.
ESRI.ArcGIS.Carto.IFeatureSelection featureSelection
=
(ESRI.ArcGIS.Carto.IFeatureSelection)layer;
//
Explicit Cast
ESRI.ArcGIS.Geodatabase.ISelectionSet selectionSet
=
featureSelection.SelectionSet;
ESRI.ArcGIS.Geodatabase.IFeatureClass featureClass
=
featureLayer.FeatureClass;
string
shapeField
=
featureClass.ShapeFieldName;
spatialFilterCls.GeometryField
=
shapeField;
spatialFilterCls.set_OutputSpatialReference(shapeField, spatialReference);
ESRI.ArcGIS.Geodatabase.ICursor cursor;
selectionSet.Search(spatialFilterCls,
true
,
out
cursor);
ESRI.ArcGIS.Geodatabase.IFeatureCursor featureCursor
=
(ESRI.ArcGIS.Geodatabase.IFeatureCursor)cursor;
//
Explicit cast.
bool
getLayerExtent
=
true
;
ESRI.ArcGIS.Geodatabase.IFeature feature;
while
((feature
=
featureCursor.NextFeature())
!=
null
)
...
{
ESRI.ArcGIS.Geometry.IGeometry geometry = feature.Shape;
ESRI.ArcGIS.Geometry.IEnvelope featureExtent = geometry.Envelope;
envelopeCls.Union(featureExtent);
haveFeatures = true;
if (getLayerExtent)
...{
ESRI.ArcGIS.Geodatabase.IGeoDataset geoDataset = (ESRI.ArcGIS.Geodatabase.IGeoDataset)featureLayer; // Explicit cast.
if (geoDataset != null)
...{
ESRI.ArcGIS.Geometry.IEnvelope layerExtent = geoDataset.Extent;
layersExtentCls.Union(layerExtent);
}
getLayerExtent = false;
}
}
}
double
width
=
envelopeCls.Width;
double
height
=
envelopeCls.Height;
if
(width
==
0.0
&&
height
==
0.0
)
...
{
double dim = 1.0;
bool bEmpty = layersExtentCls.IsEmpty;
if (!bEmpty)
...{
double layerWidth = layersExtentCls.Width;
double layerHeight = layersExtentCls.Height;
double layerDim = System.Math.Max(layerWidth, layerHeight) * 0.05;
if (layerDim > 0.0)
dim = System.Math.Min(1.0, layerDim);
}
double xMin = envelopeCls.XMin;
double yMin = envelopeCls.YMin;
ESRI.ArcGIS.Geometry.IPoint pointCls = new ESRI.ArcGIS.Geometry.PointClass();
pointCls.X = xMin;
pointCls.Y = yMin;
envelopeCls.Width = dim;
envelopeCls.Height = dim;
envelopeCls.CenterAt(pointCls);
}
else
if
(width
==
0.0
||
height
==
0.0
)
...
{
double maxDim = System.Math.Max(width, height);
envelopeCls.Width = maxDim;
envelopeCls.Height = maxDim;
}