The measurement of a photometry always refers to a punctual light source. The light distribution curve (LDC) is therefore also displayed in evo with a punctual origin.
The light calculation in evo takes the size of the light output into account. For this purpose, the photometry is divided into many small segments and distributed over the area of the light output. This also allows the light to be visualised over the entire length of the luminaire and does not only start from the measuring point of the photometry.
If a linear luminaire is placed near a wall, for example, this behaviour can be easily reproduced.