Isa Geriler

• Architecture: Three integrators in one engine: Path Tracing, Light Tracing, and Instant Radiosity (which uses a Halton quasi-Monte Carlo sampler relying on prime bases for the Radical Inverse).
• Material framework: GGX microfacets (Conductor BSDF, sampled proportionally to the NDF), Plastic (Phong), Diffuse, Oren-Nayar, Glass, Mirror, and a Layered BSDF evaluating Beer's Law for attenuation.
• Performance: Rendering distributed across CPU threads in 32 × 32 tiles, with a Binned SAH BVH (surface area heuristic bounding volume hierarchy) to reduce geometry searches and Multiple Importance Sampling (MIS) for latitude-longitude environment maps.
• Denoising: Integrated Intel Open Image Denoise using colour, albedo and normal buffers, producing denoised images at 16 samples per pixel across four test scenes.

Path Tracing Light Tracing

The thread-pool chart is a separate experiment from the sequential optimisation result. Scene 3 peaks at roughly 2.8× speedup around six threads and then declines. These results alone do not establish which cores the scheduler used or the cause of the plateau.

Scene 1

Scene 2

Scene 3

• Enemy rendering: enemies are signed distance fields sphere-traced in an HLSL shader, each with independently configurable appearance parameters, so a new silhouette is authored as SDF parameters rather than as a mesh.
• The mechanic: screen-space noise resolves while the player holds still, tying denoise convergence directly to enemy visibility and to how much ground the enemy gains while you wait.
• AI: enemy vision, pursuit and retreat written in C++, with debug draw visualization used to verify detection state during development.
• Iteration: presented in fortnightly demos to staff and peers. Movement speeds were retuned and a tutorial added directly off the back of playtest feedback.

• Weather & materials: Gerstner wave water, a Niagara rain system with splashes and puddle accumulation, and a reusable wetness layer that darkens albedo and drops roughness across the level's surfaces.
• Lighting & atmosphere: volumetric fog tuned across the whole level footprint, and interior lighting passes for the warehouse spaces the level routes players through.
• Damage feedback: a full post-process state stack — a red screen-space response on taking damage, a chromatic-aberration and slice-displacement glitch on death, and a grid overlay marking respawn invulnerability.
• Performance: Cull Distance Volumes used to scale the level's draw load across a large outdoor footprint.

Taking damage

Death

Invulnerable

Volumetric fog · level footprint

Warehouse interior lighting

The full pipeline includes model, view and projection transforms, homogeneous-coordinate mathematics, perspective-correct interpolation, a Z-buffer and Lambertian lighting. The implementation uses a custom maths library and parses .gem meshes.

• Framework features: GPU instancing, camera controls, normal mapping, parallax occlusion mapping and animated grass.
• Further development (WIP): my separate DX12 Engine re-architects this framework, with ongoing work on Descriptor Heaps, Root Signatures and Pipeline State Objects (PSOs).

Based on Ray Tracing in One Weekend (Shirley et al., 2025). The per-pixel render loop is parallelised, and BVH sorting uses C++17’s std::execution::par. This project remains a work in progress.