Weblight

Name

Enter light name <Spotlight1>: (Enter a name or press Enter to accept the default name.)

Intensity Factor

Enter intensity (0.00 - max float) <1.0>: (Enter the intensity. Values between 0.00 and the maximum value supported by your system are accepted.)

Status

Enter status OFf/<ON>: (Choose ON to include the light when calculating a rendering.)

Photometry

Enter a photometric option to change: Color/eXit/<Intensity>:

• Enter intensity (Cd) or enter an option [Flux/Illuminance] <1500.0>: (Enter the intensity expressed in Candela (Cd).)

• • Enter Flux (Lm) : (Enter the luminous flux expressed in Lumen (Lm).)

  • Enter Illuminance (Lx or Fc) or enter an option [Distance] <9424.8>: (Enter the illuminance expressed in Lux (Lx) or Foot-candle (Fc).)

  • • Enter Distance <1.0>: (Enter a distance expressed in drawing units.)

• Enter color name or enter an option [?/Kelvin] <D65>:

• • Enter color name(s) to list <*>: (Enter a color name from the list. Type * to see the list)

  • • D65

    • Fluorescent

    • Coolwhite

    • Whitefluorescent

    • daylightfluorescenT

    • Incandescent

    • Xenon

    • Halogen

    • Quartz

    • Metalhalide

    • mErcury

    • Phosphormercury

    • highpressureSodium

    • Lowpressuresodium

  • Enter Kelvin temperature <3600.0>: (Enter a color temperature expressed in degrees Kelvin (K).

Candela: The candela (symbol: cd) is the SI base unit of luminous intensity; that is, power emitted by a light source in a particular direction, weighted by the luminosity function (a standardized model of the sensitivity of the human eye to different wavelengths, also known as the luminous efficiency function). A common candle emits light with a luminous intensity of roughly one candela.

Lumen: The lumen (symbol: Lm) is the SI unit of luminous flux, a measure of the power of light perceived by the human eye. Luminous flux differs from radiant flux in that luminous flux measurements (such as lumens) are intended to reflect the varying sensitivity of the human eye to different wavelengths of light, while radiant flux measurements (such as watts) indicate the total power of light emitted. The lumen is defined in relation to the candela as: 1 lm = 1 cd·sr

As a full sphere has a solid angle of 4·pi steradians, a light source that uniformly radiates one candela in all directions has a total luminous flux of 1 cd·4pi sr = 4pi ≈ 12.57 lumens. For example, if a candle emits light with a luminous intensity of about 1 candela, the total light emitted is about 12.6 lumens.

Illuminance: In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelength-weighted by the luminosity function to correlate with human brightness perception.

If LIGHTINGUNITS=2 (International lighting units):
In SI derived units illuminance is measured in lux (lx) or lumens per square metre.

If LIGHTINGUNITS=1 (American lighting units):
The foot-candle (Fc) is a non-metric unit of illuminance that is used in photography. The unit is defined as the amount of illumination the inside surface of a 1-foot radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere. Alternatively, it can be defined as the illuminance on a 1-square foot surface of which there is a uniformly distributed flux of one lumen. This can be thought of as the amount of light that actually falls on a given surface. The foot-candle is equal to one lumen per square foot. One foot-candle is equal to approximately 10.764 lux, although in the lighting industry, typically this is approximated as 1 foot-candle being equal to 10 lux.

Kelvin temperature: Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, manufacturing, astrophysics, and other fields. The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of comparable hue to that light source. The temperature is conventionally stated in units of absolute temperature: degrees kelvin (K).

Higher color temperatures (5,000 K or more) are called cool colors (blueish white); lower color temperatures (2,700–3,000 K) are called warm colors (yellowish white through red).

Web

Enter a Web options to change: File/X/Y/Z/<Exit>: (Enter an option.)

• Enter Web file <>: Enter the name of a web file.
  An IES file is a text file that describes the intensity of a light source at points on a spherical grid.

• Enter Web X rotation in degrees <0.0000>: (Define the X rotation for the web.)

• Enter Web Y rotation in degrees <0.0000>: (Define the Y rotation for the web.)

• Enter Web Z rotation in degrees <0.0000>: (Define the Z rotation for the web.)

Shadow

Enter shadow settings [Off/Sharp/soFt mapped/soft sAmpled] <Sharp>: (Enter a shadow setting.)

• Off: Disables the calculation of shadows for the light.

• Sharp:  Displays shadows with sharp edges. Use this option to increase performance.

• Soft mapped: Displays realistic shadows with soft edges.

• • Enter map size [64/128/256/512/1024/2048/4096] <256>:

• Soft sampled:

• • Enter an option to change Shape/sAmples/Visible/<eXit>:

  • • Enter shape [Disk/Rect] <Disk>:

    • • Enter radius <0.0>: (Enter the radius of the disk.)

      • Enter Length <0.0>: (Enter length of the rectangle.)

      • Enter Width <0.0>: (Enter width of the rectangle.)

    • Enter Shadow Sample <16>:

    • Enter Shape Visibility [Yes/No] <No>:

Sharp

    Displays shadows with sharp edges. Use this option to increase performance.

Soft Mapped

    Displays realistic shadows with soft edges.

    Enter map size [64/128/256/512/1024/2048/4096] <256>:

    Specifies the amount of memory that should be used to calculate the shadow map.

    Enter softness (1-10) <1>:

    Specifies the softness to use to calculate the shadow map.

Attenuation

Enter an option to change: attenuation Type/Use limits/attenuation start Limit/attenuation End limit/<eXit>: Enter an option or press Enter to return to the base options.

• Enter attenuation type [None/Inverse linear/inverse Squared] <None>:

• • None: No attenuation. The distance to the light source has no influence.

  • Inverse linear: The attenuation is the inverse of the linear distance from the light: at a distance of 2 units from the light source, light is half as strong; at a distance of 4 units, light is one quarter as strong.

  • Inverse squared: The attenuation is the inverse of the square of the distance from the light: at a distance of 2 units, light is one quarter as strong; at a distance of 4 units, light is one sixteenth as strong.

• Specify start limit offset <1.0>: Define the point where the light starts to shine, measured from the center of the light.

• Specify end limit offset <10.0>: Define the point where the light stops to shine, measured from the center of the light.

Filter Color

Enter true color (R,G,B) or enter an option: Index color/Hsl/<255,255,255>: Defines the color of the light.

• True Color (RGB): The RGB color model is an additive color model in which red, green, and blue light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three additive primary colors, red, green, and blue. The component values are stored as integer numbers in the range 0 to 255, the range that a single 8-bit byte can offer (by encoding 256 distinct values).

• Index color: Specifies an AutoCAD Color Index color.

• HSL: Specifies the color using three parameters Hue, Saturation and Lightness.

Exit

Concludes the command and creates the light.