OrenNayar

class sonic.OrenNayar

Bases: sonic.Reflectance

This software is made available under the MIT license. See SONIC/LICENSE for details.

Constructor Summary
OrenNayar(AL, sigma, calcInterrefl)

Instantiates a sonic OrenNayar object.

Inputs:
  • AL (n,m): Albedo matrix between 0 and 1

    Note: can be scalar.

  • sigma (n,m): Surface roughness matrix

    Note: can be scalar.

  • calcInterrefl: Logical (0 = false (default), 1 = true)

    for whether the user wishes to include interreflectance in their modeling.

Outputs:

  • obj (sonic.OrenNayar): Oren-Nayar reflectance model object.

References

Last revised: 10/02/2024 Last author: Priyal Soni

Property Summary
AL

Albedo (n x m)

calcInterrefl

T/F Calculate interreflectance

sigma

Roughness (n x m) [rad]

Method Summary
static checkInterreflInput(calcInterrefl)

Checks if input is either logical or 0 or 1 for input validation.

Inputs:
  • calcInterrefl: Logical (0 = false (default), 1 = true)

    for whether the user wishes to include interreflectance in their modeling.

Outputs:

  • N/A for input validation functions

Last revised: 10/02/2024 Last author: Priyal Soni

refl(inputType, var1, var2, var3)

calculates the BRDF of a surface as described by the Oren-Nayar model.

Inputs:
  • obj (sonic.OrenNayar): Oren-Nayar reflectance

    model object.

  • inputType (string):

    • “iep” for incidence/emission/phase angles

    • “iea” for incidence/emission/azimuth angles

    • “ien” for incidence/emission/normal vectors

      – Must be column vectors, (3xn)

  • var1: Must be a double or PointsS2 object

  • var2: Must be a double or PointsS2 object

  • var3: Must be a double or PointsS2 object

Outputs:

  • r (:,: double): matrix of BRDF values

Last revised: 10/02/2024 Last author: Priyal Soni

refl_ON(i, e, cosPhi)

Calculates the reflectance of a surface as described by the Oren-Nayar model. This function uses the Oren-Nayar approximation rather than directly evaluating the model.

Inputs:
  • obj (sonic.OrenNayar): The Oren-Nayar reflectance

    model object.

  • i: incidence angles

  • e: emission angles

  • cosPhi: cosine of emission vector azimuth angle as

    measured from the plane of incidence

Outputs:

  • r (:,:) (double): matrix of BRDF values

Last revised: 10/01/2024 Last author: Priyal Soni