Playable Client
First-person Unreal laboratory
A packaged Unreal validation client provides movement, visible interaction targets, a generated test yard, simulation feedback, save and load, and reset controls.
The Project
A world built from simulation, not scripted shortcuts.
LifeSim is a standalone C++ simulation engine foundation for a persistent life-skills and survival game. It is designed around deterministic execution, conserved physical quantities, exact save and replay, long-term world change, and evidence-based consequences.
Terrain, weather, water, atmosphere, materials, tools, human condition, and practical activity are being developed as connected systems rather than isolated game mechanics.
The authoritative engine has no dependency on Unreal Engine, Unity, a renderer, an operating-system clock, or a third-party runtime. Unreal serves as a presentation client while the LifeSim engine remains the source of simulation truth.
Current version: 0.57.1
Core principles
Deterministic
Persistent
Renderer-independent
Evidence before consequence
Finite materials and energy
Exact save and replay
Working Now
The foundation is operational.
LifeSim is already playable as an engineering laboratory. The current client exists to validate simulation behavior, interaction, persistence, and presentation boundaries before the full survival scenario is built.
Human Foundation
A functional human actor
The human model currently includes posture, energy, hydration, nutrition, pain, mobility, hand use, carrying capacity, core temperature, sleep pressure, and body-region injury evidence.
Physical World
Persistent terrain and materials
Terrain can be excavated, transferred into finite loose-material lots, placed into piles, compacted, gathered, and preserved through saves without inventing or destroying volume.
Environment
Weather, water, soil, and atmosphere
The engine includes finite weather forcing, atmospheric gases, soil horizons, infiltration, runoff, aquifers, groundwater, surface water, erosion, sediment, snow, freezing, and thawing.
Interaction
Objects, tools, and persistent work
Players can inspect, carry, store, connect, pull, strike, dig, consume, clean wounds, cover wounds, stabilize injuries, and begin, pause, resume, or abandon persistent activities.
Determinism
The same causes produce the same result
Simulation state uses integer quantities and saved integration remainders. Large time advances are tested against equivalent smaller partitions to ensure exact reproducibility.
Current Development
Human interaction with the environment.
Current work is focused on connecting physical evidence from the world to human function without inventing unsupported biological outcomes.
- Body-region injury observations
- Evidence-derived mobility and hand-use constraints
- Deterministic sleep pressure
- Wound-cleaning and wound-covering records
- Injury stabilization without assumed realignment or healing
- Persistent activities and practical work
- Terrain-contact force and pressure evidence
- Environmental exposure and human consequence boundaries
Latest completed milestone: Deterministic Activity Runtime Milestone 53
Current rule
Record what physically happened first. Derive consequences only when the available evidence supports them.
Development Progress
Built in dependency order.
Each major layer must remain playable, deterministic, saveable, and accessible through the renderer-neutral interface before later systems depend on it.
Completed Foundation
Operational systems
- Deterministic kernel
- World coordinates and cells
- Terrain and excavation
- Loose material and compaction
- Matter and energy processes
- Atmosphere and combustion
- Weather and calendar
- Soil, groundwater, and surface water
- Erosion and sediment
- Human foundation
- Object interaction
- Persistent activities
- Save, load, history, and replay
- Unreal validation client
Planned Expansion
Systems still to come
- Full anatomy and injury progression
- Illness and recovery
- Plants, roots, and ecological succession
- Tree aging, branch loss, and forest-floor accumulation
- Animals and complete ecosystems
- Construction procedures and buildings
- Utilities, machines, and appliances
- Vehicles and boats
- Settlements and economy
- Production graphics and sound
- Complete survival scenarios
Long-Term World Change
The world is intended to age.
LifeSim is designed to support persistent environmental history over years and decades. Later systems are intended to account for changes such as vegetation growth, tree age, fallen and broken branches, accumulated leaves and pine needles, decay, soil changes, erosion, altered drainage, and the consequences those changes create.
Small details are not treated as decorative when they can affect fire, moisture, soil, movement, habitat, visibility, construction, or survival.
Simulation philosophy
If the world changes, something should have caused it.
Future Applications
One engine, several possible uses.
LifeSim is being developed first as the foundation for a playable survival simulation, but its systems may support other applications as the project matures.
Game
Persistent survival simulation
A playable world centered on practical knowledge, survival, environmental change, physical consequences, and long-term persistence.
Engine
Modular technology licensing
Individual systems or the larger engine may eventually be made available for licensing to developers and specialized partners.
Education
Interactive life-skills learning
Practical procedures and environmental systems may support educational scenarios where actions, conditions, and consequences can be examined directly.
Research and Training
Deterministic scenario testing
The engine architecture may support reproducible simulations, specialized training environments, and controlled scenario development.
Commercial Direction
Built as both a product and a platform.
LifeSim may eventually support consumer sales, paid testing, expansion content, engine licensing, subsystem licensing, educational use, research partnerships, or specialized simulation work.
No final commercial model has been selected. Development remains focused on building and validating the underlying simulation before deciding how public access, testing, sales, or licensing will work.
Licensing interest
Future licensing and partnership inquiries may be considered as development progresses.
Current Boundary
An engineering laboratory, not yet the finished game.
The current build is intended to prove simulation systems, determinism, persistence, and integration. It is not yet the complete survival scenario, and many coefficients remain explicitly verification-only until calibrated real-world datasets are approved.
Already Real
Implemented and testable
The deterministic engine, playable laboratory, terrain systems, environmental foundation, human foundation, interactions, activities, and persistence are working now.
Not Claimed Yet
Still under development
The project does not yet claim complete anatomy, calibrated medicine, complete ecosystems, construction, vehicles, a finished scenario, production graphics, or a final commercial release.
Documentation
A detailed development record is being preserved.
LifeSim maintains an extensive technical record of implemented systems, migration history, current limitations, architecture decisions, validation commands, milestone records, and future work.
That record is intended to support recovery, testing, final integration, public transparency, and future licensing or collaboration.
Return to SoftwareProject record
Implementation history
Architecture decisions
Milestone records
Save-format migrations
Known limitations
Future roadmap