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598 Chapter 20: Managing Scenes and Projects
Latitude and Longi tude—
Enter the latitude and
longitude where the model is located. When
calculating the daylight parameters, latitude is
displayedinredifthelatitudeistooclosetothe
poles for the chosen light to give the sun direc tion.
These are set automatically when a location is
chosen.
Time Zone—Thetimezonewherethemodelis
locate d. This is set autom atically when a location is
chosen. The time zone is used to convert between
sun time and lo ca l time.
Daylight Savings—Indicatesthatdaylightsavings
is to be used for converting between sun time and
local time. This is
not automatically set when dates
are changed.
Exterior—Indicates that the model is an exterior
scene, or par tially exterior.
12/22 to 6/22 and 6/22 to 12/22—Usually, when
calculating dates, two possible dates can be chosen
between the two solstices. This radio button
determines which solstice the date falls within.
AM and PM—Usually, when calculating times, two
times can be chosen, either in the morning or
afternoon. This radio button determines which
time is chosen. AM chooses the time before the
sun reaches its highest point, and PM the time
after the highest point. Because of local variations
between sun time and local time, these times might
not be in the morning or afternoon respectively.
Month and Day—Enter the month and day for the
date you want daylight. If your selected light places
thesuntoohighintheskyforadatethatyouenter,
thedatewillbeindicatedinredtowarnyouthat
the sun position in the preparation file w ill be
over ridden. If you want to correct the date, change
ittoadatewherethesunriseshigherinthesky.
You can also move the location to a place where
the sun rises higher in the sky.
Nor th—Enter the direction of north in degrees
clockw ise from the positive Y axis. If your selected
light places the sun too high in the sky for a
direct ion that you enter, the direction will be
indicated in red to warn y ou that the sun position
in the preparation file w ill be overridden. If you
want to correct the direction, change it toward
the lig ht. You can also move the location to a
place where the sun rises higher in the sk y at that
direction.
Time—Enter the time of day for the daylight
calculation. This will
not cause other parameters
to be calculated.
Recalculate—When on, daylight parameters are
recalculated as location, date, and north change.
Turn off Recalculate if you want to enter a l l of the
parameters directly. Turning on Recalculate
will
cause other parameters to be calculated.
Override Solar Luminance—When on, allows the
brightness of the selected light to override the
calculated br ightness of the sun. When off, the
brightness of the selected light is not exported, but
it might be used to calculate sky coverage.
Sk y—Sets the sky coverage. The sky can be set to
Clear, Partly Cloudy, or Cloudy. This affects the
brightness of the sun. If you turn on Use Light,
the brightness of the selected light wil l be used
tocalculatetheskycoveragebychoosingthe
coverage that makes the calculated sun’s brightness
closest to the light.
Lightscape Preparation File
Windows Panel
This panel is used to mark w indows and openings
for Lightscape. When daylight is used for an
interior scene, Lightscape a l lows daylight to
enter the scene only through two types of special
surfaces: windows and openings. Openings are
just placeholder surfaces that mark openings for