Package javafx.scene

Class PointLight

All Implemented Interfaces:
Styleable, EventTarget
Direct Known Subclasses:
SpotLight

public class PointLight
extends LightBase
A light source that radiates light equally in all directions away from itself. The location of the light source is a single point in space. Any pixel within the range of the light will be illuminated by it, unless it belongs to a Shape3D outside of its scope.

The light's intensity can be set to decrease over distance by attenuating it. The attenuation formula

attn = 1 / (ca + la * dist + qa * dist^2)

defines 3 coefficients: ca, la, and qa, which control the constant, linear, and quadratic behaviors of intensity falloff over distance, respectively. The effective color of the light at a given point in space is color * attn. It is possible, albeit unrealistic, to specify negative values to attenuation coefficients. This allows the resulting attenuation factor to be negative, which results in the light's color being subtracted from the material instead of added to it, thus creating a "shadow caster".

For a realistic effect, maxRange should be set to a distance at which the attenuation is close to 0 as this will give a soft cutoff.

Since:
JavaFX 8.0
See Also:
PhongMaterial
  • Property Details

    • maxRange

      public final DoubleProperty maxRangeProperty
      The maximum range of this PointLight. For a pixel to be affected by this light, its distance to the light source must be less than or equal to the light's maximum range. Any negative value will be treated as 0.

      Lower maxRange values can give better performance as pixels outside the range of the light will not require complex calculation. The attenuation formula can be used to calculate a realistic maxRange value by finding the distance where the attenuation is close enough to 0.

      Nodes that are inside the light's range can still be excluded from the light's effect by removing them from its scope (or including them in its exclusion scope). If a node is known to always be outside of the light's range, it is more performant to exclude it from its scope.

      Default value:
      Double.POSITIVE_INFINITY
      Since:
      16
      See Also:
      getMaxRange(), setMaxRange(double)
    • constantAttenuation

      public final DoubleProperty constantAttenuationProperty
      The constant attenuation coefficient. This is the term ca in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      1
      Since:
      16
      See Also:
      getConstantAttenuation(), setConstantAttenuation(double)
    • linearAttenuation

      public final DoubleProperty linearAttenuationProperty
      The linear attenuation coefficient. This is the term la in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
      See Also:
      getLinearAttenuation(), setLinearAttenuation(double)
    • quadraticAttenuation

      public final DoubleProperty quadraticAttenuationProperty
      The quadratic attenuation coefficient. This is the term qa in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
      See Also:
      getQuadraticAttenuation(), setQuadraticAttenuation(double)
  • Constructor Details

    • PointLight

      public PointLight()
      Creates a new instance of PointLight class with a default Color.WHITE light source.
    • PointLight

      public PointLight​(Color color)
      Creates a new instance of PointLight class using the specified color.
      Parameters:
      color - the color of the light source
  • Method Details

    • setMaxRange

      public final void setMaxRange​(double value)
      Sets the value of the property maxRange.
      Property description:
      The maximum range of this PointLight. For a pixel to be affected by this light, its distance to the light source must be less than or equal to the light's maximum range. Any negative value will be treated as 0.

      Lower maxRange values can give better performance as pixels outside the range of the light will not require complex calculation. The attenuation formula can be used to calculate a realistic maxRange value by finding the distance where the attenuation is close enough to 0.

      Nodes that are inside the light's range can still be excluded from the light's effect by removing them from its scope (or including them in its exclusion scope). If a node is known to always be outside of the light's range, it is more performant to exclude it from its scope.

      Default value:
      Double.POSITIVE_INFINITY
      Since:
      16
    • getMaxRange

      public final double getMaxRange()
      Gets the value of the property maxRange.
      Property description:
      The maximum range of this PointLight. For a pixel to be affected by this light, its distance to the light source must be less than or equal to the light's maximum range. Any negative value will be treated as 0.

      Lower maxRange values can give better performance as pixels outside the range of the light will not require complex calculation. The attenuation formula can be used to calculate a realistic maxRange value by finding the distance where the attenuation is close enough to 0.

      Nodes that are inside the light's range can still be excluded from the light's effect by removing them from its scope (or including them in its exclusion scope). If a node is known to always be outside of the light's range, it is more performant to exclude it from its scope.

      Default value:
      Double.POSITIVE_INFINITY
      Since:
      16
    • maxRangeProperty

      public final DoubleProperty maxRangeProperty()
      The maximum range of this PointLight. For a pixel to be affected by this light, its distance to the light source must be less than or equal to the light's maximum range. Any negative value will be treated as 0.

      Lower maxRange values can give better performance as pixels outside the range of the light will not require complex calculation. The attenuation formula can be used to calculate a realistic maxRange value by finding the distance where the attenuation is close enough to 0.

      Nodes that are inside the light's range can still be excluded from the light's effect by removing them from its scope (or including them in its exclusion scope). If a node is known to always be outside of the light's range, it is more performant to exclude it from its scope.

      Default value:
      Double.POSITIVE_INFINITY
      Since:
      16
      See Also:
      getMaxRange(), setMaxRange(double)
    • setConstantAttenuation

      public final void setConstantAttenuation​(double value)
      Sets the value of the property constantAttenuation.
      Property description:
      The constant attenuation coefficient. This is the term ca in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      1
      Since:
      16
    • getConstantAttenuation

      public final double getConstantAttenuation()
      Gets the value of the property constantAttenuation.
      Property description:
      The constant attenuation coefficient. This is the term ca in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      1
      Since:
      16
    • constantAttenuationProperty

      public final DoubleProperty constantAttenuationProperty()
      The constant attenuation coefficient. This is the term ca in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      1
      Since:
      16
      See Also:
      getConstantAttenuation(), setConstantAttenuation(double)
    • setLinearAttenuation

      public final void setLinearAttenuation​(double value)
      Sets the value of the property linearAttenuation.
      Property description:
      The linear attenuation coefficient. This is the term la in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
    • getLinearAttenuation

      public final double getLinearAttenuation()
      Gets the value of the property linearAttenuation.
      Property description:
      The linear attenuation coefficient. This is the term la in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
    • linearAttenuationProperty

      public final DoubleProperty linearAttenuationProperty()
      The linear attenuation coefficient. This is the term la in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
      See Also:
      getLinearAttenuation(), setLinearAttenuation(double)
    • setQuadraticAttenuation

      public final void setQuadraticAttenuation​(double value)
      Sets the value of the property quadraticAttenuation.
      Property description:
      The quadratic attenuation coefficient. This is the term qa in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
    • getQuadraticAttenuation

      public final double getQuadraticAttenuation()
      Gets the value of the property quadraticAttenuation.
      Property description:
      The quadratic attenuation coefficient. This is the term qa in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
    • quadraticAttenuationProperty

      public final DoubleProperty quadraticAttenuationProperty()
      The quadratic attenuation coefficient. This is the term qa in the attenuation formula:

      attn = 1 / (ca + la * dist + qa * dist^2)

      where dist is the distance between the light source and the pixel.

      Default value:
      0
      Since:
      16
      See Also:
      getQuadraticAttenuation(), setQuadraticAttenuation(double)