IfcLightDistributionDataSourceSelect
Definition from IAI: A goniometric light gets its intensity
distribution function (how much light goes in any one direction) from one of
two sources: (i) an industry-standard file, (ii) from distribution data passed
directly via the IfcLightIntensityDistribution.
The light distribution provides the luminous intensity distribution
according to some standardized light distribution curves.
Select:
| Type |
Definition |
| IfcExternalReference |
Light distribution is represented by a standard
photometric data file such as Eulumdat, IES, CIBSE TM14. |
| IfcLightIntensityDistribution |
For representing a light distribution directly the
following values needs to be given in a table like structure with column and
row headings. These headings should contain the angles (C/γ or B/β )
and the table body contains the intensity values, (normally normalized to
cd/Klm). The angles can be non- equidistant and the angle steps can be almost
any value in the valid range, so a list of all available angles in both
directions covers all cases. |
HISTORY New type in IFC Release 2x
Edition 2.
EXPRESS specification:
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| TYPE IfcLightDistributionDataSourceSelect = SELECT
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