OBJECT

OBJECT

Used in: CONFIG REQUEST
Parent elements: LAYER

<OBJECT	Attribute Description Table
units ="database \| pixel" lower ="double" [1:1] upper ="double" [1:infinity] > <LINE... /> [Or] <NORTHARROW... /> [Or] <POINT... /> [Or] <POLYGON... /> [Or] <SCALEBAR... /> [Or] <TEXT... /> [Or] <COORDSYS... /> </OBJECT >
Bold: Attribute or child element is required.

Description:

Defines the scale thresholds and units of an object to be placed on an acetate layer.

Restrictions:

Acetate layers can only be used with Image MapServices.
Acetate layers are visible only in HTML Viewers.
One of the following child elements is required: LINE, NORTHARROW, POINT, POLYGON, SCALEBAR, or TEXT. Only one can be used.

Notes:

Scales can be set in ArcXML using a relative scale or by calculating the number of map units per pixel. A relative scale represents the scale in a ratio such as 1:24000. In this example, 1 meter equals 24000 meters, or 1 inch equals 24000 inches. When using relative scale, always use a colon (:) between the two values.

Map units per pixel refers to the number of meters, feet, or decimal degrees represented by one pixel in a map. To convert from a relative scale to map units per pixel, the size of a pixel must first be calculated. The formula for finding the number of meters in a pixel is 0.0254 / dpi. The value 0.0254 is the number of meters in an inch, and dpi is the dpi set in the MapService or request. If no dpi is set in the MapService or request, the dpi is assumed to be 96. As an example of pixel size, if the dpi is 96, the pixel size is 0.0254 / 96 or 0.000265 m. To convert from a relative scale to map units per pixel:
1. If the scale is in meters. To calculate the number of meters per pixel, take the relative scale and multiply by 0.000265. For example, if the relative scale is 1:24000, then the number of meters per pixel is 24000 * 0.000265, or 6.36 meters.
2. If the scale is in feet. Do the calculation for meters (#1). Multiply the result by 3.28 (the number of feet in a meter). For example, if the number of meters per pixel is 6.36, the number of feet is 6.36 * 3.28, or 20.86 feet.
3. If the scale is in decimal degrees. For these calculations, the earth is assumed to be an exact circle with a circumference of 40030.174 km. One degree is 111.195 km (40030.174/360 degrees), or 111195 meters. To calculate the number of degrees, first do the calculation for meters (#1). Next, divide the result by 111195. For example, if the number of meters per pixel is 6.36, the number of degrees is 6.36 / 111195, or 0.0000571968.

Attribute Descriptions for OBJECT:

Attribute	Usage	Back to Top
lower	Minimum scale to display an object using a relative scale such as 1:24000. Scale can also be calculated as the number of map units per pixel.
units	Determines how coordinates for the object are specified. Coordinates can be specified two ways: Database. Refers to positioning an object using x- and y-coordinates in the coordinate system of the MapService or request. For example, if the MapService is in Robinson, then the coordinates for the object should also be in Robinson. If the coordinates for the object are different from the coordinate system used in the MapService or request, then COORDSYS should be used. <OBJECT...> <COORDSYS.../> ... </OBJECT> Pixel. Refers to positioning an object using x- and y-coordinates in pixels. The pixels along the left edge of the map frame have an x-coordinate of zero. The pixels along the bottom edge have a y-coordinate of zero.
upper	Maximum scale to display an object using a relative scale such as 1:24000. Scale can also be calculated as the number of map units per pixel.

Examples for OBJECT:

Example 1: When in CONFIG.

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<?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="-141.003006" miny="41.913319" maxx="-52.620281" maxy="83.108322" name="Initial_Extent" />
      <MAPUNITS units="decimal_degrees" />
      </PROPERTIES>
      <WORKSPACES>
      <SHAPEWORKSPACE name="shp_ws-16" directory="<path to CANADA ESRIDATA>" />
      </WORKSPACES>
      <LAYER type="featureclass" name="province" visible="true" id="0">
      <DATASET name="province" type="polygon" workspace="shp_ws-16" />
      <SIMPLERENDERER>
        <SIMPLEPOLYGONSYMBOL fillcolor="227,127,227" filltype="solid" />
      </SIMPLERENDERER>
      </LAYER>
      <LAYER type="acetate" name="Selectedmark" id="acetate">
        <OBJECT units="pixel">
          <LINE coords="0 0;400 0;400 13;0 13;0 0">
            <SIMPLELINESYMBOL color="0,0,0" />
        </LINE>
        </OBJECT>
     </LAYER>
    </MAP>
  </CONFIG>
</ARCXML>

Example 2: When in a GET_IMAGE request.

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<?xml version="1.0" encoding="UTF-8"?>
<ARCXML version="1.1">
  <REQUEST>
    <GET_IMAGE>
      <PROPERTIES>
      <ENVELOPE minx="-180" miny="-90" maxx="180" maxy="90" />
      <IMAGESIZE width="643" height="502" />
      </PROPERTIES>
      <LAYER type="acetate" name="acetate" id="acetate">
      <OBJECT units="pixel">
          <TEXT coords="100 100" label="You are here">
            <TEXTMARKERSYMBOL font="Arial" />
        </TEXT>
      </OBJECT>
      </LAYER>
    </GET_IMAGE>
  </REQUEST>
</ARCXML>