Hikari

Hikari is a physically-based offline rendering engine, which I write in my spare time to learn what goes into building a production rendering engine.

Some notable features of Hikari are (see gallery below to see them in action)-

• Cosine-weighted and emitter importance sampling
• Area Lights, Spotlights, Directional Lights and Point Lights
• Solid Angle Sampling for Spherical Area Lights which drastically reduce variance as compared to Area Sampling (see below for a comparison)
• Direct Lighting only and Path Tracing integrators
• Matte materials via Perfect Diffuse (Lambertian) and Oren-Nayar BRDF
• Analytical Spheres and Triangle Meshes via .obj files
• Mutlithreading via TBB

Gallery

Note: Following images are rendered in .ppm but were converted to .png for uploading.

Note 2: Click on the images for full size.

Emitters	Gallery
Spherical Area Light
Spot Light
Point Light

Sampling (4spp)	Gallery (rendered in under 3 seconds on Intel Core i5-7267U with two cores)
Area Sampling
Solid Angle Sampling

BRDFs	Gallery
Perfect Diffuse (Lambertian, standard deviation = 0)
Oren-Nayar (standard deviation = 90)

Integrators	Gallery
Direct Lighting only
Path Tracing