GeoMedia Geometry Representation
Intergraph’s GeoMedia stores additional information in Oracle Spatial geometry objects to represent oriented points and text features. FME’s Oracle Spatial Object reader/writer has the ability to read and write these objects directly, without going through any GeoMedia code layers.
Both oriented points and text features appear in FME as normal Oracle point features, with additional attributes to describe the additional information. These will always be present on FME features read from Oracle tables where the GeoMedia information is present. If these attributes are defined on features being written to Oracle Spatial, the geometry written will include the GeoMedia extensions.
Each feature which has GeoMedia information includes an attribute named geomedia_type, whose value tells which kind of GeoMedia geometry information is attached. The following sections describe the two types of geometry.
Oriented Point
geomedia_type:geomedia_oriented_point
GeoMedia’s oriented points add an orientation to the point. This can be specified on the FME feature either as a set of three numbers describing the orientation in 3D space, or a single value describing the planar rotation.
Attribute Name |
Contents |
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geomedia_rotation |
The orientation of the point, expressed in degrees counter-clockwise from the positive X axis. When reading, this is an approximation of the orientation described by the (i,j,k) orientation vector. When writing, this value is used to compute an (i,j,0) unit vector on the horizontal plane, if no such (i,j,k) vector is defined on the feature being written. |
geomedia_orient_i |
The “X axis” component of a vector describing the point’s orientation. This vector is normally a unit vector in 3D space. If the three components of the orientation vector are present on a feature being written, then the vector is used in place of any value present on the geomedia_rotation attribute. |
geomedia_orient_j |
The “Y axis” component of a vector describing the point’s orientation. The comments above for geomedia_orient_i apply to this attribute as well. |
geomedia_orient_k |
The “Z axis” component of a vector describing the point’s orientation. The comments above for geomedia_orient_i apply to this attribute as well. |
Text
geomedia_type:geomedia_text
GeoMedia’s text features add a plaintext or RTF text string, orientation to the point. This can be specified on the FME feature either as a set of three numbers describing the orientation in 3D space, or a single value describing the planar rotation. Features read from Oracle will have both styles of orientation defined. In this case, the planar rotation is an approximation computed from the (i,j,k) orientation values.
Attribute Name |
Contents |
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geomedia_justification |
The alignment of the text around the origin point’s coordinates. Range: 0..2, 4..6, 8..10 0 centered vertically, centered horizontally 1 centered vertically, left of the origin 2 centered vertically, right of the origin 4 above the origin, centered horizontally 5 above the origin, left of the origin 6 above the origin, right of the origin 8 below the origin, centered horizontally 9 below the origin, left of the origin 10 below the origin, right of the origin Default: 9 |
geomedia_text_string |
The plain text version of the displayed text. Text stored as formatted text in GeoMedia will have an additional attribute on the FME feature to store the RTF version of the text, as well as one to specify the font size. When writing to Oracle, the RTF version of the text will be used if it is supplied; otherwise an RTF string will be computed from the plain text string if a non-zero font size is specified. |
geomedia_rtf_text_string |
The formatted text string for the feature. Features stored as plain text in GeoMedia will not have an RTF text string attribute defined on them. When a feature with both plaintext and RTF information is written to Oracle, the RTF value will be stored into the resulting text feature; otherwise the plaintext value from geomedia_text_string will be combined with the font size from geomedia_text_font_size to compute a formatted text feature. |
geomedia_text_font_size |
The size of the formatted text feature, measured in text points. When reading, this value is extracted from the RTF text which defines the text feature. When writing, this value is used as the text size when creating an RTF string from the plaintext value in geomedia_text_string. If the feature being written contains a geomedia_rtf_text_string attribute, the font size is ignored. If the font size attribute has a zero (0) value, and no RTF text is supplied, the output text feature will be encoded as plain text. Note: GeoMedia features specify text in point size, whereas the rest of FME uses ground units for text size. The Oracle Spatial Object reader/writer does not attempt to translate between the two. |
geomedia_text_font |
The name of the font to be encoded into an RTF string for a text feature being written. If this isn’t present, a default value of “Arial” is used. (This attribute is not supplied by the reader.) |
geomedia_rotation |
The rotation of the text, measured in degrees counterclockwise from the horizontal. |