IFC 4.3.x development

8.14.3.1 IfcLightDistributionData

8.14.3.1.1 Semantic definitions at the entity

IfcLightDistributionData defines the luminous intensity of a light source given at a particular main plane angle. It is based on some standardized light distribution curves; the MainPlaneAngle is either the

For each MainPlaneAngle (considered as being the row of a table) a list of _SecondaryPlaneAngle'_s are given (considered to be the columns of a table). They are either the:

For each pair of MainPlaneAngle and SecondaryPlaneAngle the LuminousIntensity is provided (the unit is given by the IfcUnitAssignment referring to the LuminousIntensityDistributionUnit, normally cd/klm).

HISTORY  New entity in IFC2x2.

8.14.3.1.1 Attributes

#Attribute Type Description
IfcLightDistributionData
1MainPlaneAngle IfcPlaneAngleMeasure The main plane angle (A, B or C angles, according to the light distribution curve chosen).
2SecondaryPlaneAngleLIST [1:?] OF IfcPlaneAngleMeasure The list of secondary plane angles (the α, β or γ angles) according to the light distribution curve chosen.

> NOTE  The SecondaryPlaneAngle and LuminousIntensity lists are corresponding lists.
3LuminousIntensity LIST [1:?] OF IfcLuminousIntensityDistributionMeasureThe luminous intensity distribution measure for this pair of main and secondary plane angles according to the light distribution curve chosen.

8.14.3.1.2 Entity inheritance

dot_inheritance IfcLightDistributionData IfcLightDistributionData

8.14.3.1.3 Formal representations

ENTITY IfcLightDistributionData;
	MainPlaneAngle : IfcPlaneAngleMeasure;
	SecondaryPlaneAngle : LIST [1:?] OF IfcPlaneAngleMeasure;
	LuminousIntensity : LIST [1:?] OF IfcLuminousIntensityDistributionMeasure;
END_ENTITY;