Reflection technique study

Eight ways to bounce a ray off a mirror.

A research fleet of pure-C# renderers, each committed to one honest reflection technique - recursive path tracing, planar render-to-texture, cubemap probes, screen-space marching, curved and imperfect glass. No game engine, no shader language, no external image assets: every pixel is traced or rastered in plain C# against the OnlyCSharp 1.7 library (GIF encoder and seeded RNG only), then written straight to an animated GIF.

Renderers: 8
Techniques: 6
External assets: 0
Language: C# only

Rendered evidence

The reflection catalogue

Recursive ray tracing

Hall of Mirrors

Ground truth. Reflection rays are recursively traced off a perfect chrome wall and a brushed-metal panel facing it; Fresnel-Schlick weights each bounce, so the opposed mirrors dim and blur into depth as real energy is lost - never a painted fade.

m1 - 536x270 - 6 cameras - Agent 4

A flat-mirror room where the reflection is produced by re-rendering the world from a camera mirrored across the reflector plane.

Planar render-to-texture

Mirrored-Camera Room

The classic real-time flat-mirror trick, no reflection rays at all. The camera is reflected across each mirror plane, the same world is re-rendered from it into an offscreen buffer, clipped behind the plane, then stencil-composited onto the reflector.

m2 - 668x306 - 24 frames - Agent 4

Metal props sampling a cubemap probe next to a wet neon street whose reflection is marched through a screen-space buffer.

Cubemap probe + SSR

Probe & Screen-Space

Two real-time approximations and their honest limits: metal props sample a six-face HDR probe captured once per frame, while a wet neon floor marches its reflection ray through a screen-space buffer - visibly missing off-screen geometry and fading at the edge.

m4 - 488x246 - 16 frames - Agent 4

A museum row of twelve reflective specimens - chrome, silver, gold, copper, glass, ice, still water - shown under four lighting environments.

PBR material sweep

Material Mirror Museum

Twelve physically-based reflective specimens - chrome, polished silver, gold, copper, black glass, wet asphalt, still water, ice, a dusty old mirror - lit under studio, sunset, neon, and moonlight. Each reflection is a genuine recursively-traced ray, tinted by its material F0.

m3 - 632x286 - 12 specimens x 4 lights - Agent 4

Curved + imperfect glass

Funhouse Mirrors

Curved mirrors reflected with true per-pixel rays, then degraded by a physically-motivated imperfection model: dust, scratches, smudges, cracks, glass tint, edge darkening, and steam each attenuate the reflection by its own term.

m5 - 512x258 - 30 frames - Agent 4

A stealth-ops dashboard: six camera views plus eight vision-mode panels and a live stats HUD over a physics-driven water channel scene.

Multi-view vision dashboard

Night Stealth Ops

One solved physics world - buoyancy, drag, and thermal integration - rendered simultaneously through a six-camera grid, eight vision-mode panels, and a live HUD. Reflections and heat signatures read the same underlying state across every panel.

m6 - 522x484 - 48 frames - Agent 4

Real-time engine scene

Grand Power Rail Hall

A different lane: Fable.Engine, a 135-test real-time reality sim, put its reflective mirror stage to work inside a running power-hall simulation - boilers, generators, a train circuit - captured as a synchronized six-camera beauty pass.

Rail Hall - 340x220 - 6 cameras - Agent 3

Cinematic camera reel

Cathedral Board

From the mirror-subsystem lane: a scripted reel of seven intentional shots - low columns, a column wipe, a telephoto nave, stained-glass on the floor, an over-shoulder guard event - filming a reflective cathedral built entirely in C#.

Cathedral - 240x135 - 7 shots - Agent 5

Method

How these were made

Each renderer is a standalone C# console project. It builds against a small slice of the OnlyCSharp 1.7 library - the GIF byte-encoder, a seeded PCG32 RNG for jitter and soft shadows, and value noise - and reaches for nothing else. There is no OpenGL, no shading language, and no texture file on disk; the geometry, cameras, lighting, and every reflection are computed in ordinary managed code and resolved to an animated GIF.

The point of the fleet is comparison. Run the same mirror problem through recursive tracing, then a mirrored-camera pass, then a cubemap probe, and the tradeoffs stop being abstract: the traced hall shows real bounce energy loss, the screen-space floor visibly loses off-screen reflections, and the curved-glass study foregrounds the surface imperfections a clean model hides.