The model used in this tutorial
The workflows for the different daylighting simulation methods covered in this tutorial are described in the context of a simple south-facing room. The model for this room, pictured in Figure 15, was originally created in Sketchup® 2014 and then converted to Radiance format using the su2rad plugin for Sketchup (Bleicher 2008; 2016).
Figure 15. The Sketchup Model (left) and Radiance model of the space used in the tutorial.
The Radiance definitions for the geometry in the model is stored in the objects directory as shown in Figure 16. The individual definitions are arranged into a single scene by using xform as shown in Figure 17. Although individual Radiance definitions stored in the objects directory can be contained within a single file, the xform method of arranging the scene is employed throughout this tutorial as simplifies the task of adding or removing geometry from a scene. An illustrative example of this is shown in (b) and (c) of Figure 17.
The root directory contains a file with grid-points called points.txt that will be used for all the illuminance based simulations in this tutorial. Those grid-points and their directional vectors are visualized in Figure 18. The views directory contains several files that store different view specifications for the room. Low-resolution renderings for some of those views are shown in Figure 19.
Figure 16. Screen capture of the objects directory.
Figure 17. Objview rendered screen-captures of room.rad. The xform commands on each line serve to add a particular Radiance definition into the scene. The material definitions of all the objects are saved in materials.rad. Assuming that current working directory is set to room, the command for launching objview will be objview materials.rad room.rad. The images on the top row show screen captures of the files that were rendered to create images in the bottom row. The grates shown in image (b) were added to the scene by adding “!xform ./overhang/aluminiumGrate.rad” to the definition in (a). Similarly, the ground polygon in (a) and (b) was removed in (c) by commenting out “!xform ./objects/Ground.rad” in (c) with a #.
Figure 18. A visualization of the grid-points that will be used for illuminance calculations. The grid points are listed in points.txt. The geometry used to visualize the points can be found it assets/ptsArray.rad. The upward direction of the arrows indicates that the illuminance measurement is being done in the positive Z direction.
Figure 19. Objview captures of the room with different view parameters. The file corresponding to each view is mentioned on the upper-left of the rendered image for each view. The view defined in views/south.vf is used for all the image based simulations in this tutorial.