IRasterGeometryProc，一个可以控制raster对象的接口

Posted 2021-01-21 影如風

栅格影像加载到MapControl中以后，如果想更改影像的旋转、扭曲等形状，接口IRasterGeometryProc是个不错的选择。

Remarks

The RasterGeometryProc manipulates only Raster objects, not RasterBand or RasterDataset object. This is because the Raster is transient, as are the effects of the RasterGeometryProc. This means that any transformation will also go away when the Raster object goes out of scope.

To keep the transformed data for later use, you must persist the transformation using Register or Rectify. If used on a Raster contained within a RasterLayer, processing performed by this object will be visible when the display is refreshed.

Although Merge and Mosaic take Raster object as an input, any changes to the Raster object before calling the two methods will be ignored.

 

该接口只能操作Raster对象，所以针对已经加载的RasterLayer对象，可以通过Rasterlayer.Raster获取到Raster对象，然后做相应的操作。比如如下代码，使用Warp方法修改形状

IWorkspaceFactory pWSF = new RasterWorkspaceFactoryClass();
IWorkspace pWS = pWSF.OpenFromFile(workSpace, 0);

IRasterWorkspace pRWS = pWS as IRasterWorkspace;
IRasterDataset pRasterDataset = pRWS.OpenRasterDataset(file.Name);
IRasterLayer pRasterLayer = new RasterLayerClass();
pRasterLayer.CreateFromDataset(pRasterDataset);

IEnvelope envelope = pRasterLayer.AreaOfInterest;
IPointCollection originPC = new PolygonClass();
originPC.AddPoint(envelope.LowerLeft);
originPC.AddPoint(envelope.UpperLeft);
originPC.AddPoint(envelope.UpperRight);
originPC.AddPoint(envelope.LowerRight);

IPointCollection targetPointCollect = new PolygonClass();
List<CPoint> targetPointList = ImageProcessHandler.GenerateFourCoordinateList(centerPoint, entity.ImageProcessConfig.CamaraParameter, true);

IRaster raster = pRasterLayer.Raster;
IRasterGeometryProc rasterGeometryProc = new RasterGeometryProcClass();
rasterGeometryProc.Warp(originPC, targetPointCollect, esriGeoTransTypeEnum.esriGeoTransSpline, raster);

axMapControl.AddLayer(pRasterLayer);
axMapControl.Refresh();

 

 

Members

	All   Properties   Methods	Description
	Clip	Clips the input raster based on the specified envelope.
	Flip	Flips the input raster.
	IsPixelToMapTransSimple	Indicates if the transformation of pixel to map is simple.
	LeastSquareFit	Computes a least squares fit for the input control points.
	Merge	Merges the input rasters into a single dataset.
	Mirror	Mirrors the input raster.
	Mosaic	Mosaics the input rasters into a single dataset.
	PointsTransform	Transforms a set of points based upon the transformation being applied to the input raster.
	ProjectFast	Projects the input raster using a single polynomial fit to compute the adjustment between coordinate systems.
	Rectify	Persists the input raster to a new dataset of the specified format.
	Register	Outputs the current transformation properties to the dataset header or auxilliary file.
	Resample	Resamples the input raster to a new cellsize.
	ReScale	Scales the input raster by the specified x and y scale factors.
	Reset	Resets the input raster to its native coordinate space.
	Rotate	Rotates the input raster around the specified pivot by an angle specified in degrees.
	Shift	Shifts the input raster by deltaX and deltaY map units.
	TwoPointsAdjust	Performs a Hermite transformation on the input raster based upon the 2 input control point pairs.
	Warp	Warps the input raster based upon the input control points using the transformation type specified.