Autodesk 15606-011408-9008 - MAPGUIDE R6.3 NAMED-100U PK, Руководство пользователя

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Chapter 5 Working with Data in Autodesk MapGuide
Note that the names of the raster image files may not contain commas (,),
and the quotation marks (“) around the raster image file names are optional.
The names of the individual raster image files entered in the RIC may be
specified using the full absolute path name, the path relative to the RIC file
location, or only the file name itself. If only the file name of the raster image
is specified, the search will start in the directory where the RIC is located
before using the Raster Image Search Path (specified in Autodesk MapGuide
Server Admin) to locate the file.
All images in a RIC must be of the same color depth (1, 8, 24, or 32 bits);
combinations of different color depths are not supported. However, images
of different resolutions are supported. For example, you could mix 1- and 2-
meter resolution data. Also, images in a RIC can be in different formats, such
as TIFF, TGA, PNG, and so on.
Images are processed in the same order in which they are listed in the RIC.
Therefore, if two images overlap each other, the image specified later in the
list will cover the image specified earlier in the list. When you create a layer,
you can specify a transparent background for bitonal images, so the bottom
images can show through the background area of the top image. For detailed
information about creating a raster layer, choose Help
Contents, click the
Index tab, and look up “raster layers, creating.”
The extents (outer boundary) of each raster image must be specified using the
xMin, yMin, xMax, and yMax parameters. These parameters specify the
center or middle position of the lower-left and upper-right pixels of the
image (as opposed to the corners of the pixel), and they must be specified in
the same coordinate system as that used by the map and any other images in
the RIC. Autodesk MapGuide Server uses the extent parameters to quickly
determine if an image is within the viewing area without having to open the
georeference file associated with each raster image.
Generating Raster Image Catalog Files
The simplest way to generate RIC files is to use Raster Workshop, a utility
available from the Autodesk MapGuide CD. You can use this utility to create
a RIC, add raster image files to the RIC, subsample and merge the files, and
more.
You can also generate RICs manually by using an ASCII text editor or by
exporting the data in CSV format from a database. However, in many cases
the extents of the raster image file may not be readily available. For example,
ESRI world files use the coordinates of one corner and the width of each
pixel. You would have to open the image itself to determine how many pixels
it contained, and then calculate the extents for each image.
Help Index
raster layers
creating