pbrt/src/lights/point.rs

91 lines
2.5 KiB
Rust

use crate::core::light::lookup_spectrum;
use crate::core::spectrum::spectrum_to_photometric;
use crate::core::texture::FloatTexture;
use crate::utils::{Arena, FileLoc, ParameterDictionary};
use anyhow::Result;
use shared::core::geometry::Point3f;
use shared::core::light::{Light, LightBase, LightType};
use shared::core::medium::{Medium, MediumInterface};
use shared::core::shape::Shape;
use shared::core::spectrum::Spectrum;
use shared::core::texture::SpectrumType;
use shared::lights::PointLight;
use shared::spectra::RGBColorSpace;
use shared::{Float, PI, Transform};
pub trait CreatePointLight {
fn new(
render_from_light: Transform,
medium_interface: MediumInterface,
le: Spectrum,
scale: Float,
arena: &Arena,
) -> Self;
}
impl CreatePointLight for PointLight {
fn new(
render_from_light: Transform,
medium_interface: MediumInterface,
le: Spectrum,
scale: Float,
arena: &Arena,
) -> Self {
let base = LightBase::new(
LightType::DeltaPosition,
render_from_light,
medium_interface,
);
let iemit = lookup_spectrum(&le);
let i = arena.alloc((*iemit).clone());
Self { base, scale, i }
}
}
pub fn create(
render_from_light: Transform,
medium: Option<Medium>,
parameters: &ParameterDictionary,
_loc: &FileLoc,
_shape: &Shape,
_alpha: &FloatTexture,
colorspace: Option<&RGBColorSpace>,
arena: &Arena,
) -> Result<Light> {
let default_cs = crate::spectra::default_colorspace();
let cs = colorspace.unwrap_or(&default_cs);
let l = parameters
.get_one_spectrum(
"L",
Some(Spectrum::Dense(cs.illuminant)),
SpectrumType::Illuminant,
)
.unwrap();
let mut scale = parameters.get_one_float("scale", 1.)?;
scale /= spectrum_to_photometric(l);
let phi_v = parameters.get_one_float("power", 1.)?;
if phi_v > 0. {
let k_e = 4. * PI;
scale *= phi_v / k_e;
}
let from = parameters.get_one_point3f("from", Point3f::zero())?;
let tf = Transform::translate(from.into());
let final_render = render_from_light * tf;
let mi = match medium {
Some(m) => {
let ptr = arena.alloc(m);
MediumInterface {
inside: ptr,
outside: ptr,
}
}
None => MediumInterface::default(),
};
let specific = PointLight::new(final_render, mi, l, scale, arena);
Ok(Light::Point(specific))
}