ONI Calculator

Instructions

When helping users with Oxygen Not Included calculations and planning:

1. Database Location: oni-calculator/oni_data.db - SQLite database with building data
2. Decompiled Source: oni-decompiled/Assembly-CSharp/ - C# source for pattern discovery
3. Extraction Tool: oni-calculator/src/extract.rs - Rust code that parses C# into SQLite

Query the Database First

Use sqlite3 to query building data:

sqlite3 oni-calculator/oni_data.db "SELECT * FROM buildings WHERE id LIKE '%Pump%'"
sqlite3 oni-calculator/oni_data.db "SELECT building_id, rate_kg_per_s FROM building_outputs WHERE resource_id='Oxygen'"

If Data is Missing

1. Grep the decompiled source to find the pattern:

   grep -E "consumptionRate|OutputElement" oni-decompiled/Assembly-CSharp/BuildingNameConfig.cs
   

2. Update oni-calculator/src/extract.rs with a new regex pattern

3. Re-run extraction:

   cd oni-calculator && cargo run -- extract ../oni-decompiled/Assembly-CSharp --clear
   

4. Commit the fix so it persists

Key Database Tables

• buildings - id, name, power_watts (negative=consumes, positive=generates), heat_output_dtu
• building_inputs - building_id, resource_id, rate_kg_per_s
• building_outputs - building_id, resource_id, rate_kg_per_s

Common Calculations

• Buildings needed: target_rate / building_output_rate
• Power budget: Sum of power_watts (negative = consumption)
• Heat output: Sum of heat_output_dtu
• Pump duty cycle: required_rate / pump_throughput

Examples

Example 1: SPOM Planning

User: How many electrolyzers do I need for a hydrogen generator?

Claude: [Queries database for Electrolyzer outputs and HydrogenGenerator inputs]
- Electrolyzer produces 0.112 kg/s Hydrogen
- H2 Generator consumes 0.1 kg/s Hydrogen
- Answer: 0.89 Electrolyzers (practically: 1 Electrolyzer with 12% surplus)

Example 2: CO2 Handling

User: How many CO2 scrubbers for my coal generators?

Claude: [Queries database]
- Coal Generator outputs 0.02 kg/s CO2
- CO2 Scrubber consumes 0.3 kg/s CO2
- Answer: 1 scrubber handles 15 generators

Example 3: Missing Data

User: What's the throughput of a gas pump?

Claude: [Queries DB, finds data missing]
[Greps source: grep consumptionRate oni-decompiled/Assembly-CSharp/GasPumpConfig.cs]
[Finds: elementConsumer.consumptionRate = 0.5f]
[Updates extract.rs with ElementConsumer pattern]
[Re-runs extraction, commits fix]
Answer: 0.5 kg/s

Example 4: Heat Comparison

User: Which generator runs coolest?

Claude: [Queries: SELECT id, power_watts, heat_output_dtu FROM buildings WHERE power_watts > 0]
[Calculates DTU per watt for each]
Answer: Hydrogen Generator at 5 DTU/W, Coal is 15 DTU/W

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Reference

Useful Queries

-- All buildings that produce a resource
SELECT building_id, rate_kg_per_s FROM building_outputs WHERE resource_id = 'Oxygen';

-- All inputs for a building
SELECT resource_id, rate_kg_per_s FROM building_inputs WHERE building_id = 'Electrolyzer';

-- Power generators ranked by efficiency
SELECT id, power_watts, heat_output_dtu,
       heat_output_dtu / power_watts as dtu_per_watt
FROM buildings
WHERE power_watts > 0
ORDER BY dtu_per_watt;

-- Buildings that consume a resource
SELECT building_id, rate_kg_per_s FROM building_inputs WHERE resource_id = 'Water';

Extraction Patterns in extract.rs

Currently captured patterns:

• const string ID = "BuildingName" - Building IDs
• EnergyConsumptionWhenActive = 120f - Power consumption
• GeneratorWattageRating = 800f - Power generation
• ConsumedElement(new Tag("X"), rate) - ElementConverter inputs
• ConsumedElement(GameTagExtensions.Create(SimHashes.X), rate) - Alternative input format
• OutputElement(rate, SimHashes.X, ...) - ElementConverter outputs
• CreateSimpleFormula(input, rate, capacity, output, rate) - Generator fuel/exhaust
• elementConsumer.consumptionRate - Pump throughput
• conduitConsumer.consumptionRate - Pipe consumer rates

Patterns NOT yet captured (add when needed):

• Recipe-based buildings (Metal Refinery, Rock Crusher)
• Critter outputs (Hatch coal production, etc.)
• Plant growth rates
• Duplicant consumption rates

CLI Commands

cd oni-calculator

# List all buildings
cargo run -- list-buildings

# Show building details
cargo run -- building Electrolyzer

# List producible resources
cargo run -- list-resources

# Calculate production chain (picks first producer alphabetically)
cargo run -- calc Oxygen --rate 1.0 --verbose

# Re-run extraction
cargo run -- extract ../oni-decompiled/Assembly-CSharp --clear

Key ONI Numbers

Building	Power	Throughput	Heat
Electrolyzer	-120W	1 kg/s Water → 0.888 O2 + 0.112 H2	1250 DTU/s
H2 Generator	+800W	0.1 kg/s H2	4000 DTU/s
Coal Generator	+600W	1 kg/s Coal → 0.02 CO2	9000 DTU/s
Gas Pump	-240W	0.5 kg/s	0 DTU/s
Liquid Pump	-240W	10 kg/s	2000 DTU/s
CO2 Scrubber	-120W	0.3 kg/s CO2 + 1 kg/s Water	1000 DTU/s