IMAGEGENERALIZATION

Used in

Servers

Image

Parent elements

Syntax

<IMAGEGENERALIZATION	Attribute Description Table
mode="true \| false \| Any non-negative number" [true] > No Child Elements </IMAGEGENERALIZATION >

Description

Turns off Image Server generalization so that small or narrow features do not disappear.

Restrictions

Valid only with Image Services. Not valid with Feature Services.
Not valid in requests.

Notes

Generalization is used by the Image Server to speed up the processing of features, and by default, features are generalized. However, in certain cases, generalization causes some features or parts of features to drop out. This can happen with very small or narrow features. The features display when zoomed in, but as the user zooms out, part or all of an affected feature drops out. The tradeoff for not generalizing features is that the ArcIMS Spatial Server takes longer to process a request.

The accuracy is calculated based on the following formula:

(map extent width / image width ) / f

where f is the value assigned to mode. Features within this tolerance are generalized.

The attribute values for mode are interpreted as follows:
- If "true", the f value is set to "64". This is the default.
- If "false", the f value is set to "0". This means no generalization takes place.
- If a numeric value is used, the f value is assigned that numeric value. Therefore, if you use "100", the f value is set to "100". If a value less than "0" is used, the value will be reset to "64".
The smaller the accuracy, the longer the Spatial Server takes to process a request. A value of "0" will take the longest to process because no generalization is taking place. Setting mode to a value smaller than "64" may speed up the processing time, but more features will be generalized. You must remember that other factors such as the complexity of the data, complexity of the request, network traffic, and other factors can also cause a request to be slow.

Attribute Descriptions for IMAGEGENERALIZATION

Attribute	Usage
mode	Determines whether generalization is turned on. The default is "true", which means generalization is done. See the Notes section for more details.

Examples for IMAGEGENERALIZATION

Example 1: When used in CONFIG.

<?xml version="1.0" encoding="UTF-8"?>
<ARCXML version="1.1">
  <CONFIG>
    <ENVIRONMENT>
      <LOCALE country="US" language="en" variant="" />
      <UIFONT color="0,0,0" name="Arial" size="12" style="regular" />
      <SCREEN dpi="96" />
    </ENVIRONMENT>
    <MAP>
      <PROPERTIES>
        <ENVELOPE minx="-10216344.095894964" miny="13131205.105564624" maxx="-10214678.689520996" maxy="13137124.071447073" name="Initial_Extent" />
        <MAPUNITS units="meters" />
        <FILTERCOORDSYS id="54030" />
        <FEATURECOORDSYS id="54030"/>
        <IMAGEGENERALIZATION mode="true" />
      </PROPERTIES>
      <WORKSPACES>
        <SHAPEWORKSPACE name="shp_ws-0" directory="<path to data>" />
      </WORKSPACES>
      <LAYER type="featureclass" name="roads" visible="true" id="0">
        <DATASET name="roads" type="line" workspace="shp_ws-0" />
        <SIMPLERENDERER>
          <SIMPLELINESYMBOL width="1" captype="round" color="27,127,127" />
        </SIMPLERENDERER>
      </LAYER>
    </MAP>
  </CONFIG>
</ARCXML>

Example 2: When in SERVICEINFO.

<?xml version="1.0" encoding="UTF-8"?>
<ARCXML version="1.1">
  <RESPONSE>
    <SERVICEINFO>
      <ENVIRONMENT>
        <LOCALE language="en" country="US" />
        <UIFONT name="Arial" color="0,0,0" size="12" style="regular" />
        <SEPARATORS cs=" " ts=";"/>
        <CAPABILITIES forbidden="" disabledtypes=""/>
        <SCREEN dpi="96"/>
        <IMAGELIMIT pixelcount="1048576" />
      </ENVIRONMENT>
      <PROPERTIES>
        <FEATURECOORDSYS id="4326"/>
        <FILTERCOORDSYS id="4326"/>
        <ENVELOPE minx="-10216344.0958949" miny="13131205.1055646" maxx="-10214678.6895209" maxy="13137124.071447" name="Initial_Extent" />
        <MAPUNITS units="meters" />
        <IMAGEGENERALIZATION mode="true" />
      </PROPERTIES>
      <LAYERINFO type="featureclass" visible="true" name="streets" id="0">
        <FCLASS type="line"></FCLASS>
      </LAYERINFO>
    </SERVICEINFO>
  </RESPONSE>
</ARCXML>