topic Re: Help with ITinEdit.AddFromPixelBlock in ArcObjects SDK Questions

Help with ITinEdit.AddFromPixelBlock

GregMcQuat — Sat, 11 Dec 2021 23:35:35 GMT

Hey All,

I am attempting to create a TIN from a Raster Dataset:

private void Example(IRasterDataset rasterDataset, IGeometry aoi)
        {
            ITin tin = new TinClass();
            ITinEdit tinEdit = (ITinEdit)tin;
              tinEdit.InitNew(aoi.Envelope);


            var raster = rasterDataset.CreateDefaultRaster();
            var rasterProps = (IRasterProps)raster;
            var cellsize = rasterProps.MeanCellSize();


            IPnt blocksize = new PntClass();
            blocksize.SetCoords(Math.Floor(aoi.Envelope.Width / cellsize.X), Math.Floor(aoi.Envelope.Height / cellsize.Y));
            //IRasterCursor rasterCursor = raster2.CreateCursorEx(blocksize);
            var rasterCursor = ((IRaster2)raster).CreateCursorEx(blocksize);
            var pixelBlock = rasterCursor.PixelBlock;


            //Get the pixel blocks
            IPnt tlc = new PntClass();
            tlc.SetCoords(Math.Floor((aoi.Envelope.XMin - rasterProps.Extent.XMin) / cellsize.X), Math.Ceiling((rasterProps.Extent.YMax - aoi.Envelope.YMax) / cellsize.Y));
            raster.Read(tlc, pixelBlock);


            IPixelBlock3 pixelBlock3 = (IPixelBlock3)pixelBlock;
            var pixels = (System.Array)pixelBlock3.get_PixelDataByRef(0);


            object maxPoints = 3000000;
            object toleranceAchieved = false;
            object nodata = -9999.0;


            try
            {
                tinEdit.AddFromPixelBlock(aoi.Envelope.XMin + (cellsize.X / 2), aoi.Envelope.YMax - (cellsize.Y / 2), cellsize.X, cellsize.Y, nodata, pixelBlock, 1, ref maxPoints, out toleranceAchieved);
            }
            catch (Exception e)
            {
                System.Diagnostics.Debug.WriteLine(e.Message);
            }


        }

But I get a "Value does not fall within expected range" message on the exception. Any ideas?

Re: Help with ITinEdit.AddFromPixelBlock

seria — Fri, 30 Oct 2015 01:25:08 GMT

The issue is probably caused by one or more of the parameters in your tinEdit.AddFromPixelBlock() not being compatible input into the method.

I noticed that the last two parameters are supposed to passed in "by reference", but it appears that the last parameter has been passed in as "out toleranceAchieved". This could be causing your problem.

Try replacing the last two parameters with "null" objects in accordance with the example provided on the Help page below:

ITinEdit.AddFromPixelBlock Method

http://resources.arcgis.com/en/help/arcobjects-net/componenthelp/index.html#//0025000008wz000000

It says somewhere on the page:

Optional Values

pMaxPoints To indicate that this parameter is undefined, first define a variable

object Missing = Type.Missing; then pass this in as ref Missing.

pbToleranceAchieved To indicate that this parameter is undefined, first define a variable

object Missing = Type.Missing; then pass this in as ref Missing.

Replace the last two parameters with "ref Missing" and see if this resolves your issue.