Features:

Physically Based BRDFs:

Includes implementations of several widely used physically based bidirectional reflectance distribution functions (BRDFs).

Lighting Support:

• Direct Lighting: Directional lights with color, intensity, and directional controls.
• Image Based Lighting: Prefiltered environment maps are used for computing both diffuse and specular lobes. Specular lobe is approximated using Brian Karis' Split Sum technique (see references).

User Interface:

• Tweak understandable material properties.
• Change lighting settings in real-time.
• Switch between different BRDF models, meshes, textures, and environments.

Currenly Implemented Material properties:

• Roughness
• Reflectance
• Diffuse Color
• Metallic
• Clearcoat
• Clearcoat Gloss
• Sheen
• Sheen Tint
• Subsurface

Roughness value increasing from 0-1:

Reflectance value increasing from 0-1:

Clearcoat value increasing from 0-1:

Metallic value increasing from 0-1:

Currenly Implemented Diffuse Models:

• Lambertian
• Hammon
• Disney

Diffuse models (left to right) Lambertian, Hammon, Diney:

Currenly Implemented Normal Distriubtion Functions:

• GGX
• Beckman
• Blinn Phong

NDFs (left to right) Blinn Phong, Beckman, GGX:

Currenly Implemented Geometry Attenuation Functions:

• Beckman
• GGX
• Schlick GGX

Texture Support For:

• Diffuse Mapping
• Normal Mapping
• Parallax Displacement Mapping
• Roughness Mapping
• Metallic Mapping

Resources:

• Real-Time Rendering 4th Edition - Tomas Akenine-Moller et al.
• Real Shading in Unreal Engine 4 - Brian Karis
• Image-based Lighting (IBL) of PBR Materials - Thorsten Thormählen
• Textures, Environments, and Mehses sources from polyhaven.com