List of Prompts
The following prompts
are displayed.
Specify source location
<0,0,0>: Enter coordinate values or use the pointing
device
Specify target location
<0,0,-10>: Enter coordinate values or use the pointing
device
If the LIGHTINGUNITS system variable is set
to 0, the following prompt is displayed:
Enter an option to
change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit]
<eXit>:
If the LIGHTINGUNITS
system variable is set to 1 or 2, the following prompt is displayed:
Enter an option to
change [Name/Intensity
factor/Status/Photometry/shadoW/Attenuation/filterColor/eXit]
<eXit>:
NoteWhen the LIGHTINGUNITS
system variable is set to 1 or 2, the Attenuation option has no
affect on the creation of the light. It is only maintained for scripting
compatibility.
Name
Specifies the name of
the light.
Intensity/Intensity Factor
Sets the intensity or
brightness of the light.
Status
Turns the light on and
off.
Photometry
Photometry is available
when the LIGHTINGUNITS system variable is set to 1 or 2. Photometry
is the measurement of the luminous intensities of visible light
sources.
In photometry, luminous
intensity is a measure of the perceived power emitted by a light
source in a particular direction. Luminous flux is the perceived
power per unit of solid angle. The total luminous flux for a lamp
is the perceived power emitted in all directions. Luminance is the
total luminous flux incident on a surface, per unit area.
- Intensity
-
Enter an intensity value
in candelas, the perceived power in a luminous flux value, or illuminance
value for the total luminous flux incident on a surface.
- Candela (symbol: cd) is the SI unit of luminous
intensity (perceived power emitted by a light source in a particular
direction). Cd/Sr
- Lux (symbol: lx) is the SI unit of illuminance. Lm/m^2
- Foot-candle (symbol: fc) is the American
unit of illuminance. Lm/ft^2
Enter f to
specify the perceived power in a luminous flux value.
If you enter i,
you can specify the intensity of the light based on an illuminance
value.
The illuminance value
can be specified in either lux or foot-candles. Enter d to
specify a distance to use to calculate illuminance.
- Color
-
Specify the color of
the light based on a color name or a Kelvin temperature.
Enter ? to display a
list of color names. Enter a text string using wild card characters
to display a partial listing of color names, or an asterisk (*) to
display all the possible choices.
If you enter k,
you can specify the color of the light based on a Kelvin temperature
value.
- Exit
-
Shadow
Makes the light cast
shadows.
- Off
-
Turns off the display
and calculation of shadows for the light. Turning shadows off increases performance.
- Sharp
-
Displays shadows with
sharp edges. Use this option to increase performance.
- Soft Mapped
-
Displays realistic shadows
with soft edges.
- Map Size
-
Specifies the amount
of memory that should be used to calculate the shadow map.
- Softness
-
Specifies the softness
to use to calculate the shadow map.
- Soft Sampled
-
Displays realistic shadows
with softer shadows (penumbra) based on extended light sources.
- Shape
-
Specify the shape of
the shadow by entering s and then the dimensions of the
shape. (For example, the radius of the sphere or the length and
width of a rectangle.)
Attenuation
- Attenuation Type
-
Controls how light diminishes
over distance. The farther away an object is from a point light, the
darker the object appears. Attenuation is also known as decay.
- None. Sets no
attenuation. Objects far from the point light are as bright as objects
close to the light.
- Inverse Linear. Sets
attenuation to be the inverse of the linear distance from the light. For
example, at a distance of 2 units, light is half as strong as at
the point light; at a distance of 4 units, light is one quarter
as strong. The default value for inverse linear is half the maximum
intensity.
- Inverse Squared. Sets
attenuation to be the inverse of the square of the distance from
the light. For example, at a distance of 2 units, light is one quarter
as strong as at the point light; at a distance of 4 units, light
is one sixteenth as strong.
- Use Limits
-
Specifies whether to
use limits or not.
- Attenuation Start Limit
-
Specifies the point where
light starts as an offset from the center of the light.
- Attenuation End Limit
-
Specifies the point where
light ends as an offset from the center of the light. No light is
cast beyond this point. Setting an end limit increases performance
where the effect of lighting is so minimal that the calculations
are wasted processing time.
Color/Filter Color
Controls the color of
the light.
- True Color
-
Specifies a True Color.
Enter in the format R,G,B (red, green, blue).
- Index
-
Specifies an ACI (AutoCAD
Color Index) color.
- HSL
-
Specifies an HSL (hue,
saturation, luminance) color.
- Color Book
-
Specifies a color from
a color book.
