GeoElevationGrid
GeoElevationGrid is a geometry node defining a rectangular height field, with default values for a 1m by 1m square at height 0. Vertices corresponding to GeoElevationGrid height values define quadrilaterals, which are placed above or below a curved geospatial surface using geographic coordinates.
The GeoElevationGrid node belongs to the Geospatial component and its container field is geometry. It is available since X3D version 3.0 or later.
Fields
SFNode [in, out] metadata NULL [X3DMetadataObject]
Metadata are not part of the X3D world and not interpreted by the X3D browser, but they can be accessed via the ECMAScript interface.
SFNode [ ] geoOrigin NULL [GeoOrigin] (deprecated)
Field geoOrigin.
MFString [ ] geoSystem [ "GD", "WE" ]
Identifies spatial reference frame: Geodetic (GD), Geocentric (GC), Universal Transverse Mercator (UTM). Supported values: "GD" "UTM" or "GC" followed by additional quoted string parameters as appropriate for the type.
Warning
Deprecated values are GDC (use GD) and GCC (use GC).
See Also
See X3D Specification 25.2.2 Spatial reference frames See X3D Specification 25.2.4 Specifying geospatial coordinates UTM is Universal Transverse Mercator coordinate system
SFVec3d [ ] geoGridOrigin 0 0 0 (-∞,∞)
Geographic coordinate for southwest (lower-left) corner of height dataset.
SFInt32 [ ] xDimension (0,∞)
Number of elements in the height array along east-west X direction.
Hint
Total horizontal x-axis distance equals (xDimension-1) * xSpacing.
SFInt32 [ ] zDimension (0,∞)
Number of elements in the height array along north-south Z direction.
Hint
Total lateral z-axis distance equals (zDimension-1) * zSpacing.
SFDouble [ ] xSpacing 1 [0,∞)
Distance between grid-array vertices along east-west X direction.
Hints
When geoSystem is GDC, xSpacing is number of degrees of longitude. When geoSystem is UTM, xSpacing is number of eastings (meters).
SFDouble [ ] zSpacing 1 [0,∞)
Distance between grid-array vertices along north-south Z direction.
Hints
When geoSystem is GDC, zSpacing is number of degrees of latitude. When geoSystem is UTM, zSpacing is number of northings (meters).
SFFloat [in, out] yScale 1 [0,∞)
Vertical exaggeration of displayed data produced from the height array.
SFBool [ ] solid TRUE
Setting solid true means draw only one side of polygons (backface culling on), setting solid false means draw both sides of polygons (backface culling off).
Hint
If in doubt, use solid='false' for maximum visibility.
Warning
Default value true can completely hide geometry if viewed from wrong side!
SFBool [ ] ccw TRUE
Ccw = counterclockwise: ordering of vertex coordinates orientation.
Hint
Ccw false can reverse solid (backface culling) and normal-vector orientation.
SFDouble [ ] creaseAngle [0,∞)
CreaseAngle defines angle (in radians) for determining whether adjacent polygons are drawn with sharp edges or smooth shading. If angle between normals of two adjacent polygons is less than creaseAngle, smooth shading is rendered across the shared line segment.
Hint
CreaseAngle=0 means render all edges sharply, creaseAngle=3.14159 means render all edges smoothly.
Warning
Note type double, unlike ElevationGrid creaseAngle.
SFBool [ ] colorPerVertex TRUE
Whether Color node color values are applied to each vertex (true) or per quadrilateral (false).
See Also
SFBool [ ] normalPerVertex TRUE
Whether Normal node vector values are applied to each vertex (true) or per quadrilateral (false).
SFNode [in, out] color NULL [X3DColorNode]
Input/Output field color.
SFNode [in, out] texCoord NULL [X3DTextureCoordinateNode]
Input/Output field texCoord.
SFNode [in, out] normal NULL [X3DNormalNode]
Input/Output field normal.
MFDouble [in, out] height [ 0, 0 ] (-∞,∞)
Contains xDimension rows * zDimension columns floating-point values for elevation above ellipsoid.
Hints
Height array values are in row-major order from west to east, south to north. GeoGridOrigin is in southwest (lower-left) corner of height dataset.
Description
Hints
- The height array defines (xDimension-1)*(zDimension-1) quadrilaterals.
- Positive direction for normal of each triangle is on same side of the quadrilateral. Triangles are defined either counterclockwise or clockwise depending on value of ccw field.
- GeoElevationGrid can contain GeoOrigin, Color/ColorRGBA, Normal and TextureCoordinate nodes.
- Insert a Shape node before adding geometry or Appearance.
- Include <component name='Geospatial' level='1'/>
Warning
- Generated quadrilaterals can be nonplanar. Tessellation splits quadrilaterals into triangles along seam starting at initial vertex of the quadrilateral and proceeding to opposite vertex.