c3_model.txt Documented

The c3_model.txt balance file

Caesar III keeps none of its balance numbers in the executable. Building costs, labour requirements, desirability and the whole housing evolution ladder live in a plain-text file the game reads at startup, which is why rebalancing the game needs no patching at all.

Used by Caesar III

c3_model.txt ships with the game and sits beside the executable. It is plain text, editable in any editor, and the engine parses it on startup — so changing a building's cost is a text edit rather than a patch. This is the single most useful file in the game for anyone who wants to rebalance it.

The parser is forgiving about layout and strict about counts. It looks for two section markers, then reads brace-delimited groups of comma-separated integers, skipping anything that is not a digit. Whitespace and formatting between values do not matter; the number of entries does.

Sections

Found by literal string match, in this order.

ALL BUILDINGS
Followed by exactly 130 brace-delimited entries of 8 values each.
ALL HOUSES
Followed by exactly 20 brace-delimited entries of 20 values each — the housing evolution ladder, one entry per level from small tent to luxury palace.

A building entry

Eight comma-separated integers. Position is the only key — nothing in the file is named.

OffsetSizeTypeFieldDescription
1intintcostCost to build. For walls and other draggable structures this is the cost of one tile.
2intintdesirability_valueDesirability contributed at the building's own tiles.
3intintdesirability_stepHow far, in tiles, before the value steps.
4intintdesirability_step_sizeHow much the value changes at each step.
5intintdesirability_rangeMaximum distance the effect reaches.
6intintlaborersHow many people the building employs.
7–8intintRead and discarded by Julius.

House entries

Twenty values each, and between them they define the entire housing ladder: the desirability needed to evolve and the level at which a house devolves, then the requirements a house must have met — entertainment, water, religion, education, barber, bathhouse, health, how many food types, pottery, oil, furniture and wine — followed by prosperity, the maximum population of the level, and a tax multiplier.

That list is the whole of Caesar III's housing model, in twenty numbers per level. Nothing else in the game decides whether an insula becomes a villa.

Sources