When speaking with customers, a common problem we encounter is an AGI file that calculates slowly (or fails to calculate), saves slowly, and takes much longer than expected to post any change to the model. When these issues occur and there are many luminaires in the model, the cause of the behavior is often due to the choice of luminaire symbols.

Why? It’s all about “polygons”!

For instance, consider the symbols below. Both convey a circular luminaire emitting light out the bottom, but the orange “Pendant-4” symbol on the left is built from 653 polygons. The “Circle Down” symbol (right) is composed of only 14 polygons!

Both symbols will produce the same calculations (for practical purposes), but the orange symbol will take longer to calculate, redraw in Model Mode, and save. When there are not many instances of the luminaire in the model, these differences are negligible, but when there are many luminaires, perhaps hundreds, then dramatic differences can arise.

When the model shown in the image below was calculated, it took nearly 60% longer to calculate with a luminaire defined using the orange “Pendant 4” symbol than it did using the purple “Circle Down” symbol. Using Pendant-4 it also took several seconds for the Model Mode view to update after any change was made, the file took significantly longer to save, and the saved file size was twice as large.

The project contains 171 luminaires. This translates to 111,663 surfaces to calculate and redraw when the “Pendant 4” symbol is used, versus only 2,394 surfaces with the “Circle Down” symbol. Imagine, if the model contained 500 instances of the luminaire, AGI32 could struggle to calculate or even save the file using the more complex symbol.

In summary, unless there is a need to see added details in a visualization, it is always best to define luminaires using a symbol with the fewest polygons (surfaces). If the model is particularly large with a lot of luminaires, it may even be necessary to define the luminaires with the simplest possible symbols. If visualization is not important, define the luminaires using the “Null” symbol or Box Down as this has the fewest possible surfaces to consume resources.