Module coords 

Coordinate systems of the campaign map.

The campaign map uses three related coordinate systems:

• World: the f32 positions stored in startpos Coord2d nodes.
• Raw: the u16 units stored in the map files (trade_routes.ptd). raw = world * scale + 4.
• Cell: the logical hex grid of the map (HEX_MAP_DATA, 1016x720 cells in Attila’s main map). A cell is 6 raw units wide and 8 raw units high, and odd columns are shifted half a cell down.

The scales of a map (MapScale) come from its hex grid and its size in world units: the last column starts at the map’s right edge, and the last row of odd columns ends at its bottom edge. Characters placed on cells land exactly where the current game build (the one BOB uses) puts them: 518 of 518 in Attila’s main campaign. CA’s older build of the shipped startposes rounds the horizontal position differently, one ulp away at most.

Structs

EdgePiece

A piece covering some edges of a hex cell (a road or a coast), as a shape and a rotation.

HexCell

A cell of the logical hex grid of the campaign map.

MapScale

World units per raw unit of a campaign map, horizontally and vertically.

Constants

CELL_RAW_HEIGHT

Raw units per cell, vertically.

CELL_RAW_WIDTH

Raw units per cell, horizontally.

HEX_EDGES

Edges of a hex cell.

RAW_OFFSET

Offset added to raw coordinates.