HDC Internal Export Format
Introduction
Some external applications might want to use geometrical data contained in exported geometries. Export of geometrical data is available only in case of export to the HDC internal format.
Below is short description of exported geometrical data format.
Package Content
Sample exported data have content as seen in Windows File Explorer
Specifics of exported data content are described in main Package.xml file as follows (use Microsoft XML Notepad to inspect it)
Accessing Geometrical Data
This export contains only one document, with background referred as pair of .cal and .taf files, and with spots data contained in the Package_1.xml file referred from fileName attribute of Spots tag.
Besides Spots tag that lists spots from so called overlay drawing, there might be Redlining tag as well, referring to another XML file with analogical structure.
Content of spots or redlining files passed in Package_XX.xml files can be inspected using XML Notepad as follows.
Spots and Units
On top of the Spots tag, there is important Units attribute, with value declaring units in which numerical data are expressed.
List of Spot tag follows, each containing id and layer attributes, and SVG tag where content of SVG snippet is included.
Shapes and Groups
Numerical data describing geometry is expressed in SVG syntax, specific to various typed of SVG elements.
On presented sample, svg snippets contain <g> element, in which <path> element is embedded.
Geometrical data describing <path> element are contained in d attribute, coded in a way described in SVG grammar.
If it is necessary to use other units, one have to recalculate all numerical data using appropriate units coefficient.
Note that recalculation should be done in a way specific to SVG syntax.
Some other geometrical data might be expressed as <polygon> elements, e.g. as follows:
In this case, polygon corners are contained in points attribute, according to SVG syntax.
Another case might use <rect> elements as follows
with geometry described by x, y, width and height attributes.
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Transformations
Note that in some cases there may be additional transform attribute. Its presence results from geometrical transformations (moving, rotating) applied while defining geometrical shapes.
In such case, appropriate transformations have to be applied to original geometrical data if one wants to use them directly.
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Useful references
Useful links
General specs on Scalable Vector Graphics (SVG)
More info on SVG Transform
Sample shape specifications: SVG Polygon, SVG Path