2D ray guiding visualization

2D Ray guiding for bounced light — Cosine vs Guided

Rays can sample sky (not sun) through the opening. Guiding learns from bounced light. Sun is analytic.

Guided sampler

Ray overlay

SLG bins:

Sim speed (ticks/sec):

Samples / tick (per method):

Mixture p(guide):

SLG learning rate:

Sun intensity (visual + bounce strength):

Opening width:

Sun direction (deg):

Enable learning Auto-reset stats on scene change

The yellow polygon is a clipped “sun beam” (starts at the bottom corners of the opening). Rays that hit the opening gather sky radiance only (sun is excluded from sampling).

Ground truth—

Cosine—

Guided—

Weights: fill=probability, white=last guided-bin, blue=last updated-bin

Error |luminance − truth| vs samples (log x)

Direction PDFs (cosine, guided, mixed) Expand

Convergence: luminance estimate vs samples (log x) Expand

Sample density (θ histogram): cosine vs guided Expand

We estimate incident irradiance in 2D: E = ∫ L(θ)·cosθ dθ over θ ∈ [-π/2, +π/2]. The opening contributes sky only; the sun is analytic and appears only via its lit surfaces (bounce).