wito/pbrt
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Disk and Cylinder stored the phimax parameter raw. It arrives in degrees, while PBRT does radians. This one is embarassing, was causing 50x exposure

Browse source
This commit is contained in:
Wito Wiala 2026-09-02 21:59:38 +01:00
parent 4faa3cdc95
commit 1b1344c393
2 changed files with 12 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
shared/src/shapes/cylinder.rs
View file

@ -14,7 +14,7 @@ use crate::{gamma, Float, PI};
use crate::core::geometry::{SqrtExt, Tuple};
use crate::utils::interval::Interval;
use crate::utils::math::{clamp, difference_of_products, lerp, square};
use crate::utils::math::{clamp, difference_of_products, lerp, radians, square};
use core::mem;
use num_traits::Float as NumFloat;
@ -43,9 +43,11 @@ impl CylinderShape {
) -> Self {
Self {
radius,
z_min,
z_max,
phi_max,
// pbrt: `zMin(std::min(zMin, zMax)), zMax(std::max(zMin, zMax)),
// phiMax(Radians(Clamp(phiMax, 0, 360)))`. phiMax arrives in DEGREES.
z_min: z_min.min(z_max),
z_max: z_min.max(z_max),
phi_max: radians(clamp(phi_max, 0., 360.)),
render_from_object,
object_from_render,
reverse_orientation,

8
shared/src/shapes/disk.rs
View file

@ -7,7 +7,7 @@ use crate::core::shape::{
QuadricIntersection, ShapeIntersection, ShapeSample, ShapeSampleContext, ShapeTrait,
};
use crate::utils::interval::Interval;
use crate::utils::math::square;
use crate::utils::math::{clamp, radians, square};
use crate::utils::sampling::sample_uniform_disk_concentric;
use crate::utils::Transform;
use crate::{Float, PI};
@ -40,7 +40,11 @@ impl DiskShape {
radius,
inner_radius,
height,
phi_max,
// pbrt: `phiMax(Radians(Clamp(phiMax, 0, 360)))`. The parameter arrives in
// DEGREES (default 360); storing it raw made `area()` 360/2pi = 57.3x too
// large, so the sampling pdf was 57.3x too small and every direct-lighting
// contribution from a disk area light was 57.3x too bright.
phi_max: radians(clamp(phi_max, 0., 360.)),
render_from_object: render_from_object.clone(),
object_from_render,
reverse_orientation,