How to prepare SketchUp model for DL-Light calculation?


DL-Light provides tools for calculation of physically based daylight indicators for SketchUp models. To get accurate results with DL-Light, we recommend that you prepare your SketchUp models:

Work on a copy of the model

It is recommended to work on a copy of your original model, since you may need it in future for some other calculations or presentations. Make a copy of model and do all DL-Light related actions in this copy.

On Windows operating system, we recommend to place the project directory on a local hard drive.

Simplify and clean model

DL-Light calculations are based on validated ray-tracing software Radiance. They calculate daylight indicators in sensors on selected surfaces. To avoid unnecessary calculation time, simplification steps are useful, though not compulsary.
Some cleaning steps you can use:

Organize model in SketchUp layers

The organization by layer is necessary for modules that make use of materials property, like Daylight Factor, Daylight Autonomy or Watt. Material properties are attached to layers, so all the faces of a layer will get the same material.

Every face in SketchUp can have layer and material defined.
Materials in SU are used for representation purposes, but are not suitable for physically based calculations.
Layers are much better option, since all faces with the same layer can be treated as they have the same physical characteristics. Eg put in one layer objects that would be made of glass, in another layer objects made of aluminum, then wood etc.
DL-Light only exports SketchUp geometry by layers.

Recommended procedure for organizing the model by layers:

  1. Switch to ‘Color by layer’: Window -> Default Tray - > Layers -> Color by layer
  2. Remove unused layers: Window -> Default Tray - > Layers -> Purge
  3. Create layers for various real-world materials and then attach them to appropriate objects. Note that in SU it is possible to have a group/component in one layer and nested faces in different layers. Only layers attached to faces are taken into account
    You can use: To check if surfaces in your model have correct layer:

Create virtual surfaces

Detailed info on when and why are virtual surfaces may be necessary for calculations is given on page Creation of virtual surfaces.

Two cases when virtual surfaces are necessary:

Adjust surfaces orientation

To be able to calculate any daylight indicator, it is necessary for light to fall on the surface. Face orientation is important, since front side of the surface is receiving the light. Recommendations below are only for surfaces which are used for calculation:

How to activate an extension

All extensions developed by De Luminae can be used in the same SketchUp model, with restriction that only one can be active at a time. This approach is used to avoid mixing results across various daylight indicators.

When SketchUp is started, De Luminae extensions are inactive and user can work on model geometry normally.
Use menus or toolbar buttons to activate an extension. If another De Luminae extension is already in use, a confirmation is required.
When extension selection is confirmed, the user interface and all the results for previously active extension are hidden. Then the interface and results for newly selected extension are shown. The results for deactivated extension are not deleted, and will be shown when extension is reactivated.

When a new model is created or an existing model is opened, no extension results are visible until an extension is activated.

De Luminae extensions can be deactivated at any moment with click on toolbar button toggle_material_icon