*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).

HISTORY New entity in IFC2x2.

# | Attribute | Type | Description |
---|---|---|---|

IfcLightDistributionData | |||

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. > NOTE The SecondaryPlaneAngle and LuminousIntensity lists are corresponding lists. |

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. |

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