Signals the start of a CLASS object.
Inside a layer, only a single class will be used for the rendering of a feature. Each feature is tested against each class in the order in which they are defined in the mapfile. The first class that matches the its min/max scale constraints and its EXPRESSION check for the current feature will be used for rendering.
Database connection string to retrieve remote data.
An SDE connection string consists of a hostname, instance name, database name, username and password separated by commas.
A PostGIS connection string is basically a regular PostgreSQL connection string, it takes the form of “user=nobody password=****** dbname=dbname host=localhost port=5432”
An Oracle connection string: user/pass[@db]
See also
See Vector Data for specific connection information for various data sources.
Type of connection. Default is local. See additional documentation for any other type.
See also
See Vector Data for specific connection information for various data sources.
Full filename of the spatial data to process. No file extension is necessary for shapefiles. Can be specified relative to the SHAPEPATH option from the Map Object.
If this is an SDE layer, the parameter should include the name of the layer as well as the geometry column, i.e. “mylayer,shape,myversion”.
If this is a PostGIS layer, the parameter should be in the form of “<columnname> from <tablename>”, where “columnname” is the name of the column containing the geometry objects and “tablename” is the name of the table from which the geometry data will be read.
For Oracle, use “shape FROM table” or “shape FROM (SELECT statement)” or even more complex Oracle compliant queries! Note that there are important performance impacts when using spatial subqueries however. Try using MapServer’s FILTER whenever possible instead. You can also see the SQL submitted by forcing an error, for instance by submitting a DATA parameter you know won’t work, using for example a bad column name.
See also
See Vector Data for specific connection information for various data sources.
Enables debugging of a layer in the current map.
Debugging with MapServer versions >= 5.0:
Verbose output is generated and sent to the standard error output (STDERR) or the MapServer errorfile if one is set using the “MS_ERRORFILE” environment variable. You can set the environment variable by using the CONFIG parameter at the MAP level of the mapfile, such as:
CONFIG "MS_ERRORFILE" "/ms4w/tmp/ms_error.txt"
You can also set the environment variable in Apache by adding the following to your httpd.conf:
SetEnv MS_ERRORFILE "/ms4w/tmp/ms_error.txt"
Once the environment variable is set, the DEBUG mapfile parameter can be used to control the level of debugging output. Here is a description of the possible DEBUG values:
You can also set the debug level by using the “MS_DEBUGLEVEL” environment variable.
The DEBUG setting can also be specified for the entire map, by setting the DEBUG parameter in the MAP object.
For more details on this debugging mechanism, please see MS RFC 28: Redesign of LOG/DEBUG output mechanisms.
Debugging with MapServer versions < 5:
Verbose output is generated and sent to the standard error output (STDERR) or the MapServer logfile if one is set using the LOG parameter in the WEB object. Apache users will see timing details for drawing in Apache’s error_log file. Requires MapServer to be built with the DEBUG=MSDEBUG option (–with-debug configure option).
This parameter allows for data specific attribute filtering that is done at the same time spatial filtering is done, but before any CLASS expressions are evaluated. For OGR and shapefiles the string is simply a mapserver regular expression. For spatial databases the string is a SQL WHERE clause that is valid with respect to the underlying database.
For example: FILTER “type=’road’ and size <2”
(As of MapServer 5.0 this parameter is no longer available. Please see the LABEL object’s ANGLE parameter) For MapServer versions < 5.0, this is the item name in attribute table to use for class annotation angles. Values should be in degrees.
Deprecated since version 5.0.
Maximum scale at which this LAYER is labeled. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000. Implemented in MapServer 5.0, to replace the deprecated LABELMAXSCALE parameter.
See also
Since MapServer 5.0 the proper parameter to use is LABELMAXSCALEDENOM instead. The deprecated LABELMAXSCALE is the maximum scale at which this LAYER is labeled. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000.
Deprecated since version 5.0.
Minimum scale at which this LAYER is labeled. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000. Implemented in MapServer 5.0, to replace the deprecated LABELMINSCALE parameter.
See also
Since MapServer 5.0 the proper parameter to use is LABELMINSCALEDENOM instead. The deprecated LABELMINSCALE is the minimum scale at which this LAYER is labeled. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000.
Deprecated since version 5.0.
Sets context for labeling this layer, for example:
LABELREQUIRES "![orthoquads]"
means that this layer would NOT be labeled if a layer named “orthoquads” is on. The expression consists of a boolean expression based on the status of other layers, each [layer name] substring is replaced by a 0 or a 1 depending on that layer’s STATUS and then evaluated as normal. Logical operators AND and OR can be used.
(As of MapServer 5.0 this parameter is no longer available. Please see the LABEL object’s SIZE parameter) For MapServer versions < 5.0, this is the item name in attribute table to use for class annotation sizes. Values should be in pixels.
Deprecated since version 5.0.
Maximum scale at which this LAYER is drawn. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000. Implemented in MapServer 5.0, to replace the deprecated MAXSCALE parameter.
See also
Since MapServer 5.0 the proper parameter to use is MAXSCALEDENOM instead. The deprecated MAXSCALE is the maximum scale at which this LAYER is drawn. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000.
Deprecated since version 5.0.
This keyword allows for arbitrary data to be stored as name value pairs. This is used with OGC WMS to define things such as layer title. It can also allow more flexibility in creating templates, as anything you put in here will be accessible via template tags.
Example:
METADATA
title "My layer title"
author "Me!"
END
Minimum scale at which this LAYER is drawn. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000. Implemented in MapServer 5.0, to replace the deprecated MINSCALE parameter.
See also
Since MapServer 5.0 the proper parameter to use is MINSCALEDENOM instead. The deprecated MINSCALE is the minimum scale at which this LAYER is drawn. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000.
Deprecated since version 5.0.
Sets the opacity level (or the inability to see through the layer) of all classed pixels for a given layer. The value can either be an integer in the range (0-100) or the named symbol “ALPHA”. A value of 100 is opaque and 0 is fully transparent. Implemented in MapServer 5.0, to replace the deprecated TRANSPARENCY parameter.
The “ALPHA” symbol directs the MapServer rendering code to honor the indexed or alpha transparency of pixmap symbols used to style a layer. This is only needed in the case of RGB output formats, and should be used only when necessary as it is expensive to render transparent pixmap symbols onto an RGB map image.
Passes a processing directive to be used with this layer. The supported processing directives vary by layer type, and the underlying driver that processes them. Here we see the SCALE and BANDs directivMap Scalees used to autoscale raster data and alter the band mapping. All raster processing options are described in Raster Data.
PROCESSING "SCALE=AUTO"
PROCESSING "BANDS=3,2,1"
This is also where you can enable connection pooling for certain layer layer types. Connection pooling will allow MapServer to share the handle to an open database or layer connection throughout a single map draw process. Additionally, if you have FastCGI enabled, the connection handle will stay open indefinitely, or according to the options specified in the FastCGI configuration. Oracle Spatial, ArcSDE, OGR and PostGIS/PostgreSQL currently support this approach.
PROCESSING "CLOSE_CONNECTION=DEFER"
Sets the current status of the layer. Often modified by MapServer itself. Default turns the layer on permanently.
Note
In CGI mode, layers with STATUS DEFAULT cannot be turned off using normal mechanisms. It is recommended to set layers to STATUS DEFAULT while debugging a problem, but set them back to ON/OFF in normal use.
Note
For WMS, layers in the server mapfile with STATUS DEFAULT are always sent to the client.
The scale at which symbols and/or text appear full size. This allows for dynamic scaling of objects based on the scale of the map. If not set then this layer will always appear at the same size. Scaling only takes place within the limits of MINSIZE and MAXSIZE as described above. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000. Implemented in MapServer 5.0, to replace the deprecated SYMBOLSCALE parameter.
See also
Since MapServer 5.0 the proper parameter to use is SYMBOLSCALEDENOM instead. The deprecated SYMBOLSCALE is the scale at which symbols and/or text appear full size. This allows for dynamic scaling of objects based on the scale of the map. If not set then this layer will always appear at the same size. Scaling only takes place within the limits of MINSIZE and MAXSIZE as described above. Scale is given as the denominator of the actual scale fraction, for example for a map at a scale of 1:24,000 use 24000.
Deprecated since version 5.0.
Name of the tileindex file or layer. A tileindex is similar to an ArcInfo library index. The tileindex contains polygon features for each tile. The item that contains the location of the tiled data is given using the TILEITEM parameter. When a file is used as the tileindex for shapefile or raster layers, the tileindex should be a shapefile. For CONNECTIONTYPE OGR layers, any OGR supported datasource can be a tileindex. Normally the location should contain the path to the tile file relative to the shapepath, not relative to the tileindex itself. If the DATA parameter contains a value then it is added to the end of the location. When a tileindex layer is used, it works similarly to directly referring to a file, but any supported feature source can be used (ie. postgres, oracle).
Note
All files in the tileindex should have the same coordinate system, and for vector files the same set of attributes in the same order.
Since MapServer 5.0 the proper parameter to use is OPACITY. The deprecated TRANSPARENCY parameter sets the transparency level of all classed pixels for a given layer. The value can either be an integer in the range (0-100) or the named symbol “ALPHA”. Although this parameter is named “transparency”, the integer values actually parameterize layer opacity. A value of 100 is opaque and 0 is fully transparent.
The “ALPHA” symbol directs the MapServer rendering code to honor the indexed or alpha transparency of pixmap symbols used to style a layer. This is only needed in the case of RGB output formats, and should be used only when necessary as it is expensive to render transparent pixmap symbols onto an RGB map image.
Deprecated since version 5.0.
See also
Tells MapServer whether or not a particular layer needs to be transformed from some coordinate system to image coordinates. Default is true. This allows you to create shapefiles in image/graphics coordinates and therefore have features that will always be displayed in the same location on every map. Ideal for placing logos or text in maps. Remember that the graphics coordinate system has an origin in the upper left hand corner of the image, contrary to most map coordinate systems.
Version 4.10 introduces the ability to define features with coordinates given in pixels (or percentages, see UNITS), most often inline features, relative to something other than the UL corner of an image. That is what ‘TRANSFORM FALSE’ means. By setting an alternative origin it allows you to anchor something like a copyright statement to another portion of the image in a way that is independent of image size.
Specifies how the data should be drawn. Need not be the same as the shapefile type. For example, a polygon shapefile may be drawn as a point layer, but a point shapefile may not be drawn as a polygon layer. Common sense rules. Annotation means that a label point will be calculated for the features, but the feature itself will not be drawn although a marker symbol can be optionally drawn. this allows for advanced labeling like numbered highway shields. Points are labeled at that point. Polygons are labeled first using a centroid, and if that doesn’t fall in the polygon a scanline approach is used to guarantee the label falls within the feature. Lines are labeled at the middle of the longest arc in the visible portion of the line. Query only means the layer can be queried but not drawn.
In order to differentiate between POLYGONs and POLYLINEs (which do not exist as a type), simply respectively use or omit the COLOR keyword when classifying. If you use it, it’s a polygon with a fill color, otherwise it’s a polyline with only an OUTLINECOLOR.
A circle must be defined by a a minimum bounding rectangle. That is, two points that define the smallest square that can contain it. These two points are the two opposite corners of said box.
The following is an example using inline points to draw a circle:
LAYER
NAME 'inline_circles'
TYPE CIRCLE
STATUS ON
FEATURE
POINTS
74.01 -53.8
110.7 -22.16
END
END
CLASS
STYLE
COLOR 0 0 255
END
END
END
See also
For CHART layers, see the Dynamic Charting HowTo.