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1340 Chapter 15: Lights and Cameras
Inter face
Light Cone group
These parameters control hotspots and falloff (page
3–954) for spotlights.
Show Cone—Turns display of the cone on or off.
Note: Theconeisalwaysvisiblewhenalightis
selected, s o turning off this check box has no
apparent effect until you deselect the light.
Overshoot—When Overshoot (page 3–988) is set,
the l ight casts light in al l directions. However,
projections and shadows occur only within its
falloff cone.
Hotspot/B eam—Adjusts the angle of a light’s
cone. The Hotspot value is measured in degrees.
Default=43.0.
For photometric lights, the Beam angle is the
angleatwhichthelight’sintensityhasfallento50
per cent of its f u ll intensit y. (As opposed to the
Hotspot, where intensity is still 100 per cent.)
Fa lloff/Field—Adjusts the angle of a light’s
falloff. The Falloff value is measured in degrees.
Default=45.0.
For photometric lights, the Field angle is
comparable to the Falloff angle. It is the angle at
which the lig ht’s intensity has fallen to zero.
You can manipulate the hotspot and falloff by
dragging manipulators in viewports, as described
in the previous procedures, and the later section
"Manipulators for Spotlights."
You can also adjust hotspot and falloff angles in
a Light viewport (looking at the scene from the
point of view of the sp otlight).
Circle/R ectangle—De termine the shape of the
falloff and hotspot areas. S et Circle when you want
a standard, circular light. Set Rectangle when you
want a rectangular beam of light, such as lig ht cast
through a window or doorway.
Aspect—Sets the aspect ratio (page 3–911) for the
rectangular li ght be am. The Bitmap Fit button
lets you make the aspect ratio match a specified
bitmap. Default=1.0.
Bitmap Fit—If the light’s projection aspect is
rectangular, sets the aspect ratio to match a
particular bitmap. This is useful when you are
using t he light a s a projec tor light (page 3–998).
Manipulators for Spotlights
Manipulators are visible and usable whi le
the Select And Manipulate button (page 2–15) is
turnedon. Thisbuttonisonthedefaultmain
toolbar (page 3–685). When you move the mouse
over a manipulator, the manipulator turns red
to show that dragging or clicking it will have an
effect. Also, a tooltip appears, showing the name
of the object, the par ameter, and its value.
Tip: When you select multiple spotlights, all their
manipulators are accessible.
For more information on using the spotlight
manipulators, see the Procedures sect ion at the top
of this topic.
Hotspot manipulator: In a view port, drag the
hotspot circle to adjust the hotspot value.
Falloff manipulator: In a viewport, drag the falloff
to adjust the falloff value.