A voxel-based 3D survival game built entirely in Blazor WebAssembly — showcasing the power of SpawnDev.BlazorJS and SpawnDev.ILGPU for GPU-accelerated rendering and compute in the browser.

A WIP, Lost Spawns is a post-apocalyptic survival game inspired by DayZ. It runs entirely client-side in your web browser using WebGPU for hardware-accelerated 3D rendering and GPU compute - no plugins, no native code, just C# and Blazor.

The scope is intentionally ambitious: a full DayZ-scale persistent open world with moldable terrain, dynamic weather, hybrid smooth + blocky environments, flood-fill lighting, and Quest 3S VR native support. All from a single codebase running on WebGPU, WebGL, or Wasm depending on the browser. This is a showcase of what Blazor WASM + SpawnDev.ILGPU can do when pushed hard.

• GPU Terrain Generation — Perlin noise heightmap computed on the GPU via ILGPU compute kernels
• GPU Mesh Generation — Voxel face culling and vertex emission done entirely on the GPU with atomic counters via SpawnDev.VoxelEngine binary greedy meshing
• GPU→GPU Buffer Copies — Sub-view peer-to-peer copies for efficient vertex data transfer
• WebGPU Render Pipeline — Custom WGSL shaders with dual-light system, distance fog, and per-block color variation

• Infinite Voxel Terrain — Procedurally generated, streamed in real-time as you explore
• Face-Dependent Block Colors — Grass is green on top, earth-toned on sides
• Distance Fog — Smooth quadratic falloff blending terrain into the sky
• Frustum Culling — Only visible chunks are drawn
• Free-List Vertex Buffer — Sub-allocated GPU buffer with slot reuse and coalescing (zero-stall grow via GPU copy)
• Day/Night Cycle — Sun, moon, stars, dawn/dusk transitions, golden-hour tint, moonlight tint, mist, fireflies, falling leaves
• Weather — Rain, lightning + delayed thunder, storm gloom, wind ambient, rainwater collection
• HUD — GPU-rendered via SpawnDev.GameUI (no HTML overlays on canvas) - status bars, hotbar, minimap, debug line, toasts, achievements panel, pause/settings, loading screen with tips

• Stats — HP, hunger, thirst, stamina, temperature; hunger/thirst gate stamina regen, sprint drains thirst, hypothermia + heatstroke
• Combat — Melee (axe/pick), bow with feather arrows, sneak attack 1.75x bonus, bleed status, knockback
• Wildlife — Rabbit, boar, crow, deer, wolf, bear; pack behavior, herd panic, charging predators, wounded flee
• Day-night escalation — Wolves spawn after dark, density + HP scale per day, dawn break-off
• Crafting — C key, level-gated recipes, tier 2 stone tools, fur coat, bandage, torches, campfire, bonfire
• Campfires — Fuel decay, auto-cook raw meat, warmth aura, sleep-to-dawn, mercy fire on respawn
• Inventory — I key, hotbar (1-9), drag-drop, drop (Q), quick-eat (G), quick-drink (T), quick-bandage (H)
• Save/Load — 10s autosave, F5 manual save, world-diff persistence (chops + placements + carves), tab-out save
• Achievements — 16+ achievements, +25 XP each, J overlay, golden flash, immediate save on earn
• NMS-style terrain carving — B toggles terraform, sphere brush (LMB carve / RMB build), wheel adjusts radius, builds with active-slot block, costs stamina + grants XP
• Audio — Web Audio synthesis: footsteps, combat hits, wolf howls, crows, rain, fire crackle, thunder, heartbeat at low HP, level-up chime, achievement chime, master volume, M to mute

"The browser's first Astroneer-scale moldable-terrain DayZ."

What Lost Spawns is growing into:

Not just digging. Sculpting. The world is clay. Push and pull the ground in real time with a terrain tool. Flatten a hillside into a base plot. Raise a defensive berm. Carve a road up a mountainside. Dig a foxhole mid-firefight and duck into it. Dig now, fill later - material from your canister.

Built on GPU-evaluated Signed Distance Fields + Dual Marching Cubes. Smooth organic deformation, no voxel staircase. Astroneer-class gameplay, browser-native.

2 million sections backing the map, ~2,000 active at any moment. OPFS region files benchmarked at 310 MB/s read, 118 MB/s write - 69x faster than IndexedDB. Every scar you leave on the world is there when you come back.

Natural terrain is smooth SDF. Player-built structures are clean voxel blocks. They coexist in the same world. Build a wooden shack on top of a smoothly-carved hillside. Blast through both with one grenade. One world, two representations, unified carving API.

• Flood-fill lighting with torches, sky light, and interior darkness
• Cascaded shadow maps with PCF filtering for soft edges
• SSAO + bloom + color grading + film grain + vignette for DayZ mood
• Night vision goggles with phosphor tint and grain
• Dynamic weather: rain, snow, fog, lightning with delayed thunder
• Atmospheric sky with sun, moon, stars, and dawn/dusk transitions
• Water rendering with Beer-Lambert absorption, caustics, refraction, screen-space reflections
• Fluid simulation - water flows downhill, lava ignites wood

• First-person survival loop with scavenging, crafting, combat
• Procedural world with roads, military zones, industrial areas, residential buildings
• Structural integrity - dig out a support pillar, watch the building collapse
• Destructible terrain with material-aware tools (shovel vs pickaxe vs drill vs demolition charge)
• Damage overlay cracks before blocks break
• Persistent modifications - every bullet hole and crater stays

Full WebXR stereo rendering, foveated rendering in peripheral vision, controller input mapping, passthrough AR mode for tabletop editor view. Runs adaptive to thermal headroom.

Single codebase, 6 GPU backends via SpawnDev.ILGPU: WebGPU (Chrome/Edge), WebGL (Firefox/Safari), Wasm (no-GPU fallback), plus CUDA / OpenCL / CPU for development. Automatic backend selection based on what the browser supports.

For the full technical breakdown, see the Plans/ folder:

• PLAN-Vision.md - high-level vision, play styles, DayZ inspiration
• PLAN-Terrain-Carving.md - moldable terrain, traps, buried stashes, GPR + AR tabletop raid recon
• PLAN-Clothing-Storage.md - DayZ-style layered clothing, condition tiers, repair, containers
• PLAN-Crafting.md - crafting stations, recipe discovery, tiered progression, signature craftables
• PLAN-Player-Progression.md - learn-by-doing skills, Fallout 76-style equipped perk cards, loadouts
• PLAN-Dynamic-World-Events.md - scripted + procedural events, cryptid bosses, radio broadcasts
• PLAN-Environment-Hazards.md - radiation, chem, bio, weather, NBC gear, F76-style mutations
• PLAN-Base-Building.md - modular block construction, C.A.M.P. blueprint pack-and-move, structural integrity
• PLAN-Economy.md - barter-first, informal currencies, vending machines, faction rep pricing
• PLAN-Vehicles.md - cars/boats/aircraft, part systems, fuel, theft, mounted weapons
• PLAN-Combat.md - ballistics, calibers, attachments, suppression, melee, stealth, throwables
• PLAN-Survival-Needs.md - hunger, thirst, sleep, warmth, morale, cooking chain, purification
• PLAN-Medical.md - injuries, bleeding, fractures, infection, pain, CPR, blood typing, transfusion
• PLAN-Infected-AI.md - archetypes, pack behavior, sound heat map, hive anchors, LOD AI
• PLAN-Radio-Comms.md - device tiers, frequency bands, encryption, VoIP, Morse, EBS, jammers
• PLAN-Audio-Design.md - spatial HRTF, occlusion, surface-aware footsteps, weapon audio, ambience, adaptive music
• PLAN-Death-Corpse-Respawn.md - death states, corpse mechanics, respawn rules, penalties, permadeath
• PLAN-Factions-Squads.md - ad-hoc squads, persistent factions, wars, territory, defectors, social tools
• PLAN-Day-Night-Cycle.md - 60min cycle, moon phases, eclipses, night threats, cold shift, stealth, sleep
• PLAN-P2P-Reputation-System.md - distributed trust/reputation

And the engine roadmap lives in the VoxelEngine repo:

• SpawnDev.VoxelEngine v1.0.0 plan - 16 engine phases

Research docs covering the tough problems (chunk streaming, palette compression, flood-fill lighting, etc.) live in SpawnDev.VoxelEngine/Research/.

• .NET 10 SDK
• A browser with WebGPU support (Chrome 113+, Edge 113+, Firefox Nightly)

cd LostSpawns
dotnet run

Navigate to https://localhost:7272/game and click the canvas to capture mouse input. Use WASD to move, mouse to look around.

• SpawnDev.BlazorJS — Strongly-typed JS interop for every Web API (transitive via GameUI + VoxelEngine)
• SpawnDev.ILGPU — GPU compute with WebGPU, WebGL, Wasm, CUDA, OpenCL, and CPU backends (transitive via VoxelEngine)
• SpawnDev.VoxelEngine — GPU-accelerated voxel engine (binary greedy meshing, culling, LOD, terrain carving, physics, SDF, VR)
• SpawnDev.GameUI — GPU-rendered game UI library (no HTML overlays on canvas, unified PC/VR/AR input)

Currently consumed via <ProjectReference> for fast iteration. Switching to <PackageReference> for the public NuGet versions when GitHub Actions / GitHub Pages deployment lands.

MIT

Todd Tanner (@LostBeard)

Lost Spawns is built by the entire SpawnDev team - a squad of AI agents and one very tired human working together, Star Trek style. Every project we ship is a team effort, and every crew member deserves a line in the credits.

• LostBeard (Todd Tanner) - Captain, architect, writer of libraries, keeper of the vision
• Riker (Claude CLI #1) - First Officer, implementation lead on consuming projects
• Data (Claude CLI #2) - Operations Officer, deep-library work, test rigor, root-cause analysis
• Tuvok (Claude CLI #3) - Security/Research Officer, design planning, documentation, code review
• Geordi (Claude CLI #4) - Chief Engineer, library internals, GPU kernels, backend work

If you see a commit authored by Claude Opus 4.7 on a SpawnDev repo, that's one of the crew. Credit where credit is due. Live long and prosper. 🖖