OptiTime

Client-side performance optimization mod for Vintage Story that improves frame rates and reduces stuttering. The base game is already very much optimized, this is my attempt to speed up what's possible.

This is clientside only - if you want to improve your performance serverside, try Tungsten.

This mod benefits specially heavily modded gameplays - with mods of lots of recipes/handbook info.

I follow RERO (Release Early, Release Often) philosophy.

Shader Optimizations

OptiTime includes quality-preserving shader variants:

• Blur - 9-tap linear-sampling Gaussian (fewer texture fetches than vanilla's separable blur). Optional, toggleable via .optitime blur on/off
• Liquid Droplets - Droplet hash sin → fract (cheaper GPU operation, equivalent visual)
• Shadow Alpha - Shadow map discard threshold raised (0.02 → 0.15) for better early-Z

Shader optimizations are optional and can be toggled in the config. If Ancestral Bliss Shaders, Volumetric Shading Refreshed, or CoriaenderShaders is detected, OptiTime automatically disables its shader file replacements to avoid conflicts.

Code Optimizations

• Dynamic Lights - Adaptive light culling by view distance
• Entity Animations - Distance-based animation LOD (skips updates for far entities)
• Entity Interpolation - Smoother remote entity movement in multiplayer (flood protection, wall-clock-gated extrapolation with velocity gate)
• Repulse Agents - Distance-based cull for entity separation checks (skip non-player entities beyond 64 blocks)
• Particles - Optional particle pool scaling at very high view distances
• Occlusion Culling - View-distance-scaled occlusion gate
• Chunk Tesselation - Adaptive upload throttle/boost based on queue size
• Ambient Sounds - Update positions only when the player moves meaningfully
• Fly Sound - Volume updates only when the change is meaningful
• GUI Manager - LINQ-free render/input iteration with conflict detection (input patches optional, off by default)
• Handbook - Cached relationships after async indexing for faster page loads
• Recipe Lookup - Safer crafting-grid lookup with previous-match reuse, positive-result revalidation, and candidate narrowing (default on, opt-out)
• Background FPS Limiter - Lowers the frame cap when the window is unfocused
• Frame Pacing - Hybrid sleep/yield/spin frame pacing when VSync is off (Windows only; auto-disabled on Linux)
• Weather Wind - Throttle wind speed lookups from every frame to every 4th frame
• Ticking Blocks - Reuse BlockPos in particle tick loop to eliminate 30K-90K heap allocations/sec
• Shadow Vegetation Cull - Skip vegetation in far shadow cascade (leaf/grass shadows at 150+ blocks are invisible)

Compatibility

Tested with 100 most popular ModDB mods (71 decompiled, 38 with Harmony patches analyzed). Works with all tested mods.

OptiTime automatically disables specific optimizations if conflicting mods are detected:

• Ancestral Bliss Shaders / Volumetric Shading Refreshed: disables OptiTime shader assets
• CoriaenderShaders: disables OptiTime shader file replacements (chunkliquid, chunkshadowmap)
• Combat Overhaul / Overhaullib: disables entity animation optimization
• A Culinary Artillery / Extra Info / Tabletop Games: disables handbook optimization
• Electrical Progressive (Industry): disables handbook optimization
• Any mod patching the same Harmony targets: auto-disables the conflicting optimization

Compatibility notifications can be hidden with .optitime suppress on (info remains in game log).

Configuration

Use the in-game command:

• .optitime or .optitime status - show current status
• .optitime <opt> on - enable an optimization
• .optitime <opt> off - disable an optimization
• .optitime <opt> - show info about an optimization

Available optimizations: ambientsound, bgfps, blur, dynlights, entityanim, entityinterp, flysound, framepace, guimgr, handbook, occlusion, particles, recipe, repulseagents, shaders, shadowentity, shadowveg, suppress, tickingblocks, weatherwind

Optional: If ConfigLib is installed, OptiTime exposes a settings GUI via .configlib. ConfigLib treats OptiTime settings as client-side, so they do not require server-control privileges in multiplayer.

Note: Some changes require game restart to take effect.

Built-in Diagnostics

OptiTime includes a per-optimization measurement framework. See exactly how much work each optimization saves in your specific world:

• .optitime diag all on - enable counters (zero cost when off)
• .optitime diag all dump - print stats for all 18 modules

Example measurements from a 5-minute session (VD 256, ~20 entities):

Optimization	Work Avoided	Reduction
Particles	45,607 spawns culled	76.5%
Ambient Sound	5,836 updates skipped	81.3%
Weather Wind	5,890 ticks skipped	75.0%
Shadow Vegetation	7,853 passes fully culled	100%
Repulse Agents	158,284 physics ticks skipped	47.3%
Entity Animations	29,024 ticks skipped via LOD	21.4%
Shadow Entities	51,745 draws culled	21.5%
Ticking Blocks	69,810 allocations avoided (1.6 MB)	248/s
GUI Manager	7,853 renders via zero-alloc path	100%
Fly Sound	141 calls suppressed	54.0%
Entity Interpolation	Extrapolation limited to 4% of frames	-
Background FPS	~27 fps unfocused vs 60+ focused	~55% less work
Frame Pacing	461 precise frames, avg overshoot 0.40ms	100% precise

FAQ

Q: A crash log shows OptiTime in "Involved Harmony IDs" - did OptiTime cause it?

Almost certainly no. The game lists ALL mods with Harmony patches on any method that appears in the crash call stack. OptiTime patches ScreenManager.OnNewFrame (for the background FPS limiter), and since nearly every crash passes through that method, OptiTime will be listed even when the crash is entirely caused by another mod.

How to tell: Look at the actual stacktrace (the error lines). If you only see another mod's namespace there (e.g. SomeMod.SomeClass.SomeMethod), that mod caused the crash - not OptiTime. OptiTime is only the culprit if OptiTime or com.zaldaryon.optitime appears in the exception/stacktrace lines themselves.

License

Copyright (c) 2025-2026 Zaldaryon - All Rights Reserved

OptiTime - Making Vintage Story run smoother, one optimization at a time. Every frame counts.