emitters¶

class emitter_t : public wt::scene::scene_element_t

Subclassed by wt::emitter::area_t, wt::emitter::infinite_emitter_t, wt::emitter::point_t, wt::emitter::spot_t

Public Functions

inline emitter_t(std::string id, f_t emitter_phase_space_extent_scale = 1)

emitter_t(const emitter_t&) = default

emitter_t(emitter_t&&) = default

virtual ~emitter_t() noexcept = default

inline virtual bool is_area_emitter() const noexcept

inline virtual bool is_infinite_emitter() const noexcept

virtual bool is_delta_position() const noexcept = 0

virtual bool is_delta_direction() const noexcept = 0

inline auto get_requested_phase_space_extent_scale() const noexcept: Returns the requested scale factor for the phase-space extent of emitted radiation beams.

virtual const spectrum::spectrum_real_t &emission_spectrum() const noexcept = 0: Returns the emitter’s emission spectrum.

virtual spectral_radiant_flux_t power(wavenumber_t k) const noexcept = 0: Computes total emitted spectral power.

virtual radiant_flux_t power(const range_t<wavenumber_t> &krange) const noexcept = 0: Computes total emitted power over a wavenumber range.

virtual spectral_radiant_flux_stokes_t Li(const importance_flux_beam_t &beam, const intersection_surface_t *surface) const noexcept = 0

Integrate a detector beam over the emitter.

Parameters:: beam – detection beam incident upon the emitter

virtual emitter_sample_t sample(sampler::sampler_t &sampler, const wavenumber_t k) const noexcept = 0

Samples an emission phase-space position (ray) on the light source.

Parameters:: k – wavenumber

virtual position_sample_t sample_position(sampler::sampler_t &sampler) const noexcept = 0: Samples an emission phase-space position (ray) on the light source.

virtual emitter_direct_sample_t sample_direct(sampler::sampler_t &sampler, const pqvec3_t &wp, const wavenumber_t k) const noexcept = 0

Samples a direct connection to a world position.

Parameters:

wp – world position
k – wavenumber

virtual area_sampling_pd_t pdf_position(const pqvec3_t &p, const intersection_surface_t *surface = nullptr) const noexcept = 0

Sampling PDF of an emission position on the light source.

Parameters:

p – position on light source
surface – emitter surface intersection record (this is required for area emitters)

virtual solid_angle_sampling_pd_t pdf_direction(const pqvec3_t &p, const dir3_t &dir, const intersection_surface_t *surface = nullptr) const noexcept = 0

Sampling PDF of an emission direction from the light source.

Parameters:

p – position on light source
dir – emission direction
surface – emitter surface intersection record (this is required for area emitters)

inline area_sampling_pd_t pdf_position(const intersection_surface_t &surface) const noexcept

Sampling PDF of an emission position on the light source.

Parameters:: surface – emitter surface intersection record

inline solid_angle_sampling_pd_t pdf_direction(const intersection_surface_t &surface, const dir3_t &dir) const noexcept

Sampling PDF of an emission direction from the light source.

Parameters:

surface – emitter surface intersection record
dir – emission direction

virtual solid_angle_sampling_pd_t pdf_direct(const pqvec3_t &wp, const ray_t &r, const intersection_surface_t *surface = nullptr) const noexcept = 0

Sampling PDF of a direct connection.

Parameters:

wp – world position from which direct sampling was applied
sampled_r – sampled emitter phase-space position (ray)
sampled_surface – sampled surface for emitter samples that seat on a surface (required for area emitters)

Returns:

the solid angle density from wp

inline solid_angle_sampling_pd_t pdf_direct(const intersection_surface_t &surface, const ray_t &r) const noexcept

Sampling PDF of a direct connection.

Parameters:

wp – world position from which direct sampling was applied
sampled_r – sampled emitter phase-space position (ray)
sampled_surface – sampled surface for emitter samples that seat on a surface (required for area emitters)

Returns:

the solid angle density from wp

virtual scene::element::info_t description() const override = 0

Public Static Functions

static inline constexpr std::string scene_element_class() noexcept

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

Friends

friend class wt::scene_t

friend class wt::scene::scene_sensor_t