Class SphericalHarmonics

constructor

• new SphericalHarmonics(): SphericalHarmonics

  Returns SphericalHarmonics

l00

l1_1

l10

l11

l2_1

l2_2

l20

l21

l22

preScaled

addLight

• addLight(direction: Vector3, color: Color3, deltaSolidAngle: number): void

  Adds a light to the spherical harmonics

  Parameters

  • direction: Vector3

    the direction of the light

  • color: Color3

    the color of the light

  • deltaSolidAngle: number

    the delta solid angle of the light

  Returns void

convertIncidentRadianceToIrradiance

• convertIncidentRadianceToIrradiance(): void

  Convert from incident radiance (Li) to irradiance (E) by applying convolution with the cosine-weighted hemisphere.

  E_lm = A_l * L_lm
  Copy

  In spherical harmonics this convolution amounts to scaling factors for each frequency band. This corresponds to equation 5 in "An Efficient Representation for Irradiance Environment Maps", where the scaling factors are given in equation 9.

  Returns void

convertIrradianceToLambertianRadiance

• convertIrradianceToLambertianRadiance(): void

  Convert from irradiance to outgoing radiance for Lambertian BDRF, suitable for efficient shader evaluation.

  L = (1/pi) * E * rho
  Copy

  This is done by an additional scale by 1/pi, so is a fairly trivial operation but important conceptually.

  Returns void

preScaleForRendering

• preScaleForRendering(): void

  Integrates the reconstruction coefficients directly in to the SH preventing further required operations at run time.

  This is simply done by scaling back the SH with Ylm constants parameter. The trigonometric part being applied by the shader at run time.

  Returns void

scaleInPlace

• scaleInPlace(scale: number): void

  Scales the spherical harmonics by the given amount

  Parameters

  • scale: number

    the amount to scale

  Returns void

updateFromArray

• updateFromArray(data: ArrayLike<ArrayLike<number>>): SphericalHarmonics

  update the spherical harmonics coefficients from the given array

  Parameters

  • data: ArrayLike<ArrayLike<number>>

    defines the 9x3 coefficients (l00, l1-1, l10, l11, l2-2, l2-1, l20, l21, l22)

  Returns SphericalHarmonics

  the spherical harmonics (this)

updateFromFloatsArray

• updateFromFloatsArray(data: ArrayLike<number>): SphericalHarmonics

  update the spherical harmonics coefficients from the given floats array

  Parameters

  • data: ArrayLike<number>

    defines the 9x3 coefficients (l00, l1-1, l10, l11, l2-2, l2-1, l20, l21, l22)

  Returns SphericalHarmonics

  the spherical harmonics (this)

StaticFromArray

• FromArray(data: ArrayLike<ArrayLike<number>>): SphericalHarmonics

  Constructs a spherical harmonics from an array.

  Parameters

  • data: ArrayLike<ArrayLike<number>>

    defines the 9x3 coefficients (l00, l1-1, l10, l11, l2-2, l2-1, l20, l21, l22)

  Returns SphericalHarmonics

  the spherical harmonics

StaticFromPolynomial

• FromPolynomial(polynomial: SphericalPolynomial): SphericalHarmonics

  Gets the spherical harmonics from polynomial

  Parameters

  • polynomial: SphericalPolynomial

    the spherical polynomial

  Returns SphericalHarmonics

  the spherical harmonics