diffuse BSDF¶

class diffuse_t : public wt::bsdf::bsdf_t

Idealized Lambertian (perfectly-diffusing) interface. Diffuse BSDF admit no transmission: all light is diffusely scattered into the upper hemisphere.

Public Functions

inline diffuse_t(std::string id, std::shared_ptr<texture::texture_t> reflectance)

inline virtual std::optional<f_t> albedo(const wavenumber_t k) const noexcept override

Spectral albedo. Returns std::nullopt when albedo cannot be computed.

inline virtual lobe_mask_t lobes(wavenumber_t k) const noexcept override: Returns mask of all available lobes for this BSDF at particular wavenumber.

inline virtual bool is_delta_only(const wavenumber_t k) const noexcept override: Does this BSDF comprise of only delta lobes?

inline virtual bool is_delta_lobe(wavenumber_t k, std::uint32_t lobe) const noexcept override: Is a lobe a delta lobe?

inline virtual bool needs_interaction_footprint() const noexcept override: Returns true for BSDF that make use of the surface interaction footprint data.

virtual bsdf_result_t f(const dir3_t &wi, const dir3_t &wo, const bsdf_query_t &query) const noexcept override: Evaluates the BSDF. Accounts for the cosine foreshortening term.

virtual std::optional<bsdf_sample_t> sample(const dir3_t &wi, const bsdf_query_t &query, sampler::sampler_t &sampler) const noexcept override

Samples the BSDF. The returned weight is bsdf/pdf.

Parameters:: S – normalized Stokes parameters vector that describes the polarimetric properties of incident radiation.

virtual solid_angle_density_t pdf(const dir3_t &wi, const dir3_t &wo, const bsdf_query_t &query) const noexcept override

Provides the sample density.

Parameters:: S – normalized Stokes parameters vector that describes the polarimetric properties of incident radiation.

inline virtual f_t eta(const dir3_t &wi, const dir3_t &wo, const wavenumber_t k) const noexcept override

Computes the refractive-index ratio: eta at exit / eta at entry.

Public Static Functions

static std::unique_ptr<bsdf_t> load(std::string id, scene::loader::loader_t *loader, const scene::loader::node_t &node, const wt::wt_context_t &context)