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kmlcesiumjs

KML and altitude

I have the following KML file which is a cube => 

</Placemark>
<Style id="3Dobject">
    <PolyStyle>
        <color>7fff5500</color>
        <outline>1</outline>
        <fill>1</fill>
    </PolyStyle>
</Style>
<Placemark>
    <name>Warehouse01</name>
    <description>Warehouse Center：106.97777777 -6.19758333</description>
    <styleUrl>#3Dobject</styleUrl>
    <Polygon>
        <extrude>1</extrude>
        <tessellate>1</tessellate>
        <altitudeMode>absolute</altitudeMode>
        <outerBoundaryIs>
            <LinearRing>
                <coordinates>
                    106.9772778,-6.19808333,100
                    106.9782778,-6.19808333,100
                    106.9782778,-6.19708333,100
                    106.9772778,-6.19708333,100
                    106.9772778,-6.19808333,100
                </coordinates>
            </LinearRing>
        </outerBoundaryIs>
    </Polygon>
</Placemark>

I am trying to make this cube to be drawn 100meters above the ground. (

so basically =>

enter image description here

I tried adding an 100 but it always display from the botom.

I am using CESIUM.

Solution

  • Option 1: MultiGeometry with 6 polygons

    By definition extrude makes a geometry in KML connect to the ground. To create a 3-D cube above the ground then you must turn off extude and represent a polygon for each of the 6 faces of the cube.

    Example:

    <?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">

<Placemark>
  <name>Altitude PolyCube Example</name>
  <Style>
    <PolyStyle>
        <color>7fffffff</color>
    </PolyStyle>
  </Style>
  <MultiGeometry>
    <Polygon>
      <!-- bottom panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
     106.9772778,-6.19808333,100
     106.9782778,-6.19808333,100
     106.9782778,-6.19708333,100
     106.9772778,-6.19708333,100
     106.9772778,-6.19808333,100
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

    <Polygon>
      <!-- top panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
     106.9772778,-6.19808333,200
     106.9782778,-6.19808333,200
     106.9782778,-6.19708333,200
     106.9772778,-6.19708333,200
     106.9772778,-6.19808333,200
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

    <Polygon>
      <!-- left panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
     106.9772778,-6.19808333,100
     106.9772778,-6.19808333,200
     106.9772778,-6.19708333,200
     106.9772778,-6.19708333,100
     106.9772778,-6.19808333,100
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

    <Polygon>
      <!-- right panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
    106.9782778,-6.19808333,100
    106.9782778,-6.19808333,200
    106.9782778,-6.19708333,200
    106.9782778,-6.19708333,100
    106.9782778,-6.19808333,100
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

    <Polygon>
      <!-- front panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
     106.9772778,-6.19808333,100
     106.9782778,-6.19808333,100
     106.9782778,-6.19808333,200
     106.9772778,-6.19808333,200
     106.9772778,-6.19808333,100
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

    <Polygon>
      <!-- back panel -->
      <altitudeMode>absolute</altitudeMode>
      <outerBoundaryIs>
        <LinearRing>
          <coordinates>
     106.9772778,-6.19708333,100
     106.9782778,-6.19708333,100
     106.9782778,-6.19708333,200
     106.9772778,-6.19708333,200
     106.9772778,-6.19708333,100
          </coordinates>
        </LinearRing>
      </outerBoundaryIs>
    </Polygon>

  </MultiGeometry>
</Placemark>

</kml>

    Option 2: KML and COLLADA Cube Model

    Given a generic cube model (which you can download at the 3D Warehouse), the KML can place a cube at a given location including at an altitude above ground.

    Option 3: Cesium

    Cesium using a Box geometry so can simply place a Box at a given altitude of 100 meters. For example see Cesium Sandcastle Box Demo.