FDO .NET API Reference

Feature Data Objects

mgIRaster.h

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/*
* Copyright (C) 2004-2006  Autodesk, Inc.
* 
* This library is free software; you can redistribute it and/or
* modify it under the terms of version 2.1 of the GNU Lesser
* General Public License as published by the Free Software Foundation.
* 
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
* Lesser General Public License for more details.
* 
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*
*/

#pragma once

BEGIN_NAMESPACE_OSGEO_COMMON
public __gc __interface IStreamReader;
END_NAMESPACE_OSGEO_COMMON

BEGIN_NAMESPACE_OSGEO_FDO_EXPRESSION
public __gc class DataValue;
END_NAMESPACE_OSGEO_FDO_EXPRESSION

BEGIN_NAMESPACE_OSGEO_FDO_RASTER
public __gc class RasterDataModel;
public __gc __interface IRasterPropertyDictionary;

/// \ingroup (OSGeoFDORaster)
/// \interface OSGeo::FDO::Raster::IRaster
/// \brief
/// The IRaster interface specifies the data type and organization
/// of raster data retrieved and stored. Using this class and the image
/// extents in width and length, the binary format of the image data returned
/// by and accepted by the IoStreamReader class can be interpreted.
public __gc __interface IRaster : public System::IDisposable
{
public:

    /// \brief
    /// Returns true if the IRaster represents a null value.
    /// 
    /// \return
    /// Returns true if the IRaster represents a null value.
    /// 
    System::Boolean IsNull ();

    /// \brief
    /// Sets the IRaster to a null value.
    /// 
    /// \return
    /// Returns nothing
    /// 
    System::Void SetNull ();

    /// \brief
    /// Gets the number of bands/channels contained in the raster image.
    /// 
    /// \return
    /// Returns the numbers of bands/channels contained in the raster image. 
    /// 
    __property System::Int32 get_NumberOfBands();

    /// \brief
    /// Sets the number of bands/channels contained in the raster image.
    /// 
    /// \return
    /// Returns nothing. 
    /// 
    __property System::Void set_NumberOfBands (System::Int32 value);

    /// \brief
    /// Gets the currently active band/channel.
    /// 
    /// \remarks
    /// IRaster Bounds, DataModel, ImageSize, AuxilliaryProperties and Stream 
    /// accessors all conform to the current band. 
    /// 
    /// \return
    /// Returns the current active band/channel. 
    /// 
    __property System::Int32 get_CurrentBand ();

    /// \brief
    /// Sets the currently active band/channel.
    /// 
    /// \remarks
    /// Setting the current band will mean that the Bounds, DataModel, ImageSize, 
    /// AuxilliaryProperties and Stream accessors of IRaster 
    /// will all switch to the specified band. 
    /// 
    /// \return
    /// Returns nothing. 
    /// 
    __property System::Void set_CurrentBand (System::Int32 value);

    /// \brief
    /// Get the minimum bounding box around the curent band of the image.
    ///
    /// \return
    /// Returns the bounds of the raster image
    /// 
    __property System::Byte get_Bounds () [];

    /// \brief
    /// Set the minimum bounding box around the image.
    /// For georeferenced images, the coordinate system is specified by the
    /// spatial context in force when the object is created.  The act of
    /// setting this property georeferences the image.  In order to provide
    /// for non-georeferenced images, this property is Nullable (doesn't
    /// need to be set).
    ///
    /// \param bounds 
    /// The new bounds of the raster image.
    /// 
    __property System::Void set_Bounds (System::Byte bounds[]);

    /// \brief
    /// Gets the data model in use by this raster property.
    /// 
    /// \return
    /// Returns the current data model.
    /// 
    __property NAMESPACE_OSGEO_FDO_RASTER::RasterDataModel* get_DataModel ();

    /// \brief
    /// Sets the data model used by this raster property.
    /// Allowed values are only those data models that are acceptable to the
    /// SupportsDataModel capability.
    ///
    /// \remarks
    /// This attribute specifies the colour/palette model, bits per pixel,
    /// tiling and interleaving. For example, if the bits per pixel of the
    /// data model is 8 and it is set to 24, a conversion would be performed
    /// when image data is requested, to return 24 bit data.  If an update
    /// command is executed to save this value, the raster data would be
    /// transformed and saved.  The next time this image is retrieved
    /// by the client the bits per pixel value would indicate 24.
    /// 
    /// \param dataModel 
    /// The datamodel to be used.
    /// 
    __property System::Void set_DataModel (NAMESPACE_OSGEO_FDO_RASTER::RasterDataModel* dataModel);

    /// \brief
    /// Gets the size of image file in the horizontal
    /// direction in pixels (number of columns).
    /// 
    /// \return
    /// Returns the horizontal image size in pixels
    /// (number of columns).
    /// 
    __property System::Int32 get_ImageXSize ();

    /// \brief
    /// Sets the size of image file in the horizontal
    /// direction in pixels (number of columns).
    /// By setting the X and Y image size properties prior to getting
    /// a reader for the data, the client application can control the
    /// density of pixels fetched by the provider, which may reduce
    /// the amount of data shipped by the reader and reduce processing
    /// time significantly.  For example, a certain query in the
    /// coordinate system of the raster object class returns a
    /// IRaster object with image size 12091 by 8043.  But the
    /// image only needs to be displayed in an area 1167 by 776 on
    /// the users monitor. 
    /// <p>(<b>Note:</b> The aspect ratios are the same
    /// because the query is constructed based on the display area).
    /// <p>By setting the image size to these lower values the FDO raster
    /// subsystem may be able to use a previously subsampled image
    /// where the resolution has been reduced by a factor of 4.
    /// So instead of transferring 97MB, it can transfer 6MB (a reduction
    /// by 4 in both dimensions reduces the amount of data by a factor of 16)
    /// and subsample the image again to the desired resolution in a
    /// more timely manner (less data to process means less total time),
    /// with no appreciable difference in display quality to the user.
    /// 
    /// \param size 
    /// The desired horizontal image size in pixels
    /// (number of columns).
    /// 
    __property System::Void set_ImageXSize (System::Int32 size);

    /// \brief
    /// Gets the size of image file in the vertical
    /// direction in pixels (number of rows).
    /// 
    /// \return
    /// Returns the vertical image size in pixels
    /// (number of rows).
    /// 
    __property System::Int32 get_ImageYSize ();

    /// \brief
    /// Sets the size of image file in the vertical
    /// direction in pixels (number of rows). See SetImageXSize.
    /// 
    /// \param size 
    /// The desired vertical image size in pixels
    /// (number of rows).
    /// 
    __property System ::Void set_ImageYSize (System ::Int32 size);

    /// \brief
    /// Get a dictionary style interface to the raster properties.
    /// Through this interface the non-standard properties of a raster
    /// image can be determined and their values can be retrieved and set.
    /// Data values are exchanged through the DataValue object to
    /// accommodate various data types, boolean, integer, double, string,
    /// etc.
    /// 
    /// \return
    /// The dictionary of auxilliary raster properties.
    /// 
    NAMESPACE_OSGEO_FDO_RASTER::IRasterPropertyDictionary* GetAuxiliaryProperties();

    /// \brief
    /// Gets the pixel value that represents a NULL value in the available raster stream. 
    /// 
    /// \remarks
    /// The Null Pixel Value is Data Model dependent. The value of the Null pixel
    /// will change depending on which data model is set. If the client application changes 
    /// the Data Model using SetDataModel(RasterDataModel* datamodel) a subsequent 
    /// call to GetNullPixelValue will need to be made in order to determine the valid Null 
    /// value for the current data model.
    /// 
    /// \return
    /// Returns the DataType value that can be used to identify the Null value. 
    /// 
    __property NAMESPACE_OSGEO_FDO_EXPRESSION::DataValue* get_NullPixelValue ();

    /// \brief
    /// Set the source of image data.
    /// Image data is shipped using a paradigm similar to BLOB I/O.
    /// When inserting or updating an object with a raster property,
    /// the SetStreamReader method provides a means to set a
    /// IStreamReader callback.
    /// On execution of an insert or update command, requests are made on
    /// the reader for the image data (which is supplied by the FDO client
    /// application).
    /// The format of the image data expected is determined by the
    /// DataModel property.  The data type, bit depth, tiling and
    /// organization specify the meaning of the image data.
    /// By setting the DataModel property prior to setting a
    /// reader for the data, the FDO client application can control the
    /// way data is understood by, the FDO raster subsystem.
    /// 
    __property System ::Void set_StreamReader (NAMESPACE_OSGEO_COMMON::IStreamReaderImp* reader);

    /// \brief
    /// Get the source of image data.
    /// Image data is shipped using a paradigm similar to BLOB I/O.
    /// When fetching a raster image the GetStreamReader() method provides
    /// a IStreamReader from which the client may request the image data.
    /// The format of the image data expected is determined by the
    /// DataModel property.  The data type, bit depth, tiling and
    /// organization specify the meaning of the image data.
    /// By setting the DataModel property prior to getting a
    /// reader for the data, the FDO client application can control the
    /// way data is retrieved from the FDO raster subsystem.
    /// When a tiled image is fetched, the image data will be tiled by default,
    /// unless a spatial query is used that covers a portion of a tile,
    /// in which case the image is converted to monolithic form prior to
    /// returning to the client.  The client may force a monolithic
    /// image in the former case by setting the DataModel to monolithic
    /// prior to getting the stream reader.  Or conversely it can request
    /// a re-tiling of the remaining sub-image by setting the DataModel
    /// property to tiled (in this case the tile origin is at the new upper
    /// left corner of the sub-image).
    /// <p><b>Note:</b> Altering the DataModel may have significant performance issues.
    /// 
    __property NAMESPACE_OSGEO_COMMON::IStreamReaderImp* get_StreamReader ();

    /// \brief
    /// Gets the Vertical Unit of Measure corresponding to the Raster Band.
    /// The string value returned will be a considered lookup value that
    /// will be used to identify the properties of the Unit of Measure using
    /// the IGetMeasureUnits command.
    ///
    /// \return
    /// Returns the Unit of Measure type of data associated to the Raster Band.
    ///
    __property System::String* get_VerticalUnits ();

    /// \brief
    /// Sets the Vertical Unit of Measure corresponding to the Raster Band.
    ///
    /// \param units
    /// The Unit of Measure type for the current band.
    /// The units string value corresponds to a Unit of Measure supported
    /// through the IGetMeasureUnits command.
    __property System::Void set_VerticalUnits (System::String* units);

};

END_NAMESPACE_OSGEO_FDO_RASTER

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