CreateArc

The CreateArc method creates an arc in the 3D Window.

HRESULTCreateArc (

[in] double X,

[in] double Y,

[in] double Elevation,

[in] double RadiusX,

[in] double RadiusY,

[in, defaultvalue(-90)] double StartAngle,

[in, defaultvalue(90)] double EndEngle,

[in, defaultvalue(12)] int NumOfSegments,

[in, defaultvalue(0x0000ff00)] long LineColor,

[in, defaultvalue(FT_NONE)] double FillOpacity,

[in, defaultvalue(0x00646464)] long FillColor,

[in, defaultvalue(HSC_TERRAIN_RELATIVE)] HeightStyleCode HeightStyle,

[in, defaultvalue(0)] long GroupID,

[in, defaultvalue("")] BSTR Description,

[out, retval] ITerrainArc5** pITerrainArc5)

Parameters:

• X – The West-East coordinate of the center of the arc represented in MPT units. You can use the ITerrain interface to retrieve information about the MPT units. If you are working in Lat-Long format, the Lat-Long values are in decimal Lat-Long.

• Y – The North-South coordinate of the center of the arc represented in MPT units. You can use the ITerrain interface to retrieve information about the MPT units. If you are working in Lat-Long format, the Lat-Long values are in decimal Lat-Long.

• Elevation – The elevation of the arc. The HeightStyle parameter determines how TerraExplorer interprets this parameter.

• RadiusX – The radius of the arc along the x-axis (in meters).

• RadiusY – The radius of the arc along the y-axis (in meters)

• StartAngle – The angle at which the arc begins.

• EndAngle – The angle at which the arc ends.

• LineColor – The color of the lines that make up the arc. The color value is used to specify an RGB color. When specifying an explicit RGB color, the color value has the following hexadecimal form: 0x00bbggrr. The low-order byte contains a value for the relative intensity of red; the second byte contains a value for green; and the third byte contains a value for blue. The high-order byte must be zero. The maximum value for a single byte is 0xFF.

• FillOpacity – Determines the opacity or transparency of the fill of the arc. This value can be any value between 0, for transparent, and 1 for opaque.

• FillColor – The color with which the arc is filled if the FillOpacity value is greater than 0. The color value is used to specify an RGB color. When specifying an explicit RGB color, the color value has the following hexadecimal form: 0x00bbggrr. The low-order byte contains a value for the relative intensity of red; the second byte contains a value for green; and the third byte contains a value for blue. The high-order byte must be zero. The maximum value for a single byte is 0xFF.

• HeightStyle – An enum determining how the arc is placed on the terrain relative to the ground.

The HeightStyleCode enum can use any of the following values:

• HSC_TERRAIN_RELATIVE = 0
  All of the arc’s vertices are at the same elevation above the terrain (determined by the Elevation parameter).

• HSC_PIVOT_RELATIVE = 1
  The elevation parameter determines the height of the arc pivot above the terrain. All of the arc’s vertices are at the same plane as the pivot.

• HSC_ON_TERRAIN = 2
  All of the arc’s vertices are situated on the ground (the Elevation parameter is ignored).

• HSC_TERRAIN_ABSOLUTE = 3
  Each of the arc’s vertices has a height relative to the terrain database vertical datum base ellipsoid.

• GroupID – The Information Tree group in which the arc was created. If it is set to zero, the object is created under the root. You can obtain the GroupID by one of the following methods:

• Create the group the IInformationTree5::CreateGroup.

• If you know the name of the group, find it using IInformationTree5::FindItem.

• Traverse the Tree using IInformationTree5 methods such as GetNextItem, until you come to the desired GroupID.

• Description – The name of the arc as it appears in the Information Window. If an empty string is passed into this parameter, TerraExplorer assigns it a unique name.

• pITerrainArc5 – An interface pointer to the newly created arc. The pointer must not be Null.

Return Values:

The return value obtained from the returned HRESULT can be one of the following: