8.14.3.1 IfcLightDistributionData
8.14.3.1.1 Semantic definition
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
- A angle; if the IfcLightDistributionCurveEnum is set to TYPE_A
 - B angle; if the IfcLightDistributionCurveEnum is set to TYPE_B
 - C angle; if the IfcLightDistributionCurveEnum is set to TYPE_C
 
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:
- α angle; if the IfcLightDistributionCurveEnum is set to TYPE_A
 - β angle; if the IfcLightDistributionCurveEnum is set to TYPE_B
 - γ angle; if the IfcLightDistributionCurveEnum is set to TYPE_C
 
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).
8.14.3.1.2 Entity inheritance
8.14.3.1.3 Attributes
| # | Attribute | Type | Description | 
|---|---|---|---|
| IfcLightDistributionData (3) | |||
| 1 | MainPlaneAngle | IfcPlaneAngleMeasure | 
 The main plane angle (A, B or C angles, according to the light distribution curve chosen).  | 
| 2 | SecondaryPlaneAngle | LIST [1:?] OF IfcPlaneAngleMeasure | 
 The list of secondary plane angles (the α, β or γ angles) according to the light distribution curve chosen.  | 
| 3 | LuminousIntensity | LIST [1:?] OF IfcLuminousIntensityDistributionMeasure | 
 The luminous intensity distribution measure for this pair of main and secondary plane angles according to the light distribution curve chosen.  | 
8.14.3.1.4 Formal representation
ENTITY IfcLightDistributionData;
	MainPlaneAngle : IfcPlaneAngleMeasure;
	SecondaryPlaneAngle : LIST [1:?] OF IfcPlaneAngleMeasure;
	LuminousIntensity : LIST [1:?] OF IfcLuminousIntensityDistributionMeasure;
END_ENTITY;