Graphics Programs Reference
In-Depth Information
Sun and Sky Simulation feature offers a more accurate rendition of refl ected light that takes
into account the light bouncing off neighboring buildings and surfaces. To see how this feature
works, try the following exercise:
1.
At the Command prompt, enter
Lightingunits
↵.
2.
At the Enter new value for LIGHTINGUNITS <0>: prompt, enter
2
.
If you have a drawing that uses distant lights, you may see a warning message asking if you
want to disable distant lights. Leave them enabled by selecting Allow Distant Lights.
By changing the Lightingunits setting, you turn on the Photometric Lighting feature in
AutoCAD. The Photometric Lighting feature gives you fi ner control over the intensity of
the lights you add to your model. The Lightingunits system variable can be set to 0 (generic
units), 1 (international units), or 2 (American units). When you are in a perspective view and
Lightingunits is set to 1 or 2, you can turn on the Sun and Sky Simulation feature.
This next exercise demonstrates how the Sun and Sky Simulation feature works:
1.
Click the Sky Status pop-up menu in the Status Bar palette and select the Sky Background
And Illumination option.
2.
The background of your main view changes.
3.
Click the Render tool. After a minute or two, you get a fi nished rendering. Your model
renders using the current Sun settings. The shadows on the center building are more
realistic and show more detail of the building (Figure 21.14).
FIGURE 21.14
The rendering
with the Sky Back-
ground And Illu-
mination feature
turned on
