We cannot guarantee that the program is safe to download as it will be downloaded from the developer's website. Before launching the program, check it with any free antivirus software. The following version: 1.1 is the most frequently downloaded one by the program users. The actual developer of the free program is Timur Dogan. UrbanDaylight for Rhino belongs to Photo & Graphics Tools.
From the developer:
The UrbanDaylight is a Rhino5 and Grasshopper plugin that allows designers to simulate and evaluate the daylight potential of large urban designs. The tool automates exterior DAYSIM simulations for all buildings in the city model. Given the solar radiation on the facades, it uses a generalized impulse response to compute the interior illumination on an hour-by-hour basis. This allows us to use the data for climate-based metrics.
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