README.md

⚡ Gen City

Procedural city generation

.

Demo

Documentation

• Install
• Generation
• General
• Nodes
• Paths
• Buildings
• Example

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Install

npm i gen-city

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Generation

Create city

const city = new City(params)

Param	Description	Default
width	Map width	-
height	Map height	-

Generate

await city.generate(params?)

Param	Description	Default
mode	Generation mode. * Runtime - Random generation in runtime * Seed - Generation follows the specified seed	Runtime
seed	Generation seed array for seed mode	-
startPosition	Position of the first node.	Center of map
startDirections	Start generation directions	Left, Right, Top, Bottom
streetMinLength	Street length before generating an intersection or turn	10
probabilityIntersection	Probability of generating intersection	0.1
probabilityTurn	Probability of generating turn	0.05
probabilityStreetEnd	Probability of generating street end	0.001
buildingMinSize	Minimum building size	3
buildingMaxSize	Maximum building size	6
buildingMinSpace	Minimum distance between buildings	1
buildingMaxSpace	Maximum distance between buildings	3
buildingOffset	Distance between building and path	0

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General

Get size

const width = city.width
const height = city.height

Get seed

Return seed if city was generated with runtime mode

const seed = city.getSeed(): number[] | null

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Nodes

Get all nodes

const nodes = city.getAllNodes(): Node[]

Get node paths

const inputPaths = node.getInputPaths(): Path[]
const outputPaths = node.getOutputPaths(): Path[]
const allPaths = node.getAllPaths(): Path[]

Get node type

Get type by count of input and output paths (Turn, Cross, End)

const type = node.getType(): NodeType

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Paths

Get all paths

const paths = city.getAllPaths(): Path[]

Get path positions

const positions = path.getPositions(): { 
  beg: Position
  end: Position
}

Get path nodes

const nodeBeg = path.getNodeBeg(): Node
const nodeEnd = path.getNodeEnd(): Node

Get path length

const length = path.getLength(): number

Each path positions

path.each(callback: (position: Position) => void)

Remove path from nodes

path.remove()

Get path buildings

const buildings = path.getBuildings(): Building[]

Get path direction

Get direction in degrees

const direction: number = path.direction

.

Buildings

Get all buildings

const buildings = city.getAllBuildings(): Building[]

Get building vertices

Array of rectangle corners positions

const vertices: Position[] = building.vertices

Get building position

Get top left corner position

const position: Position = building.position

Get building size

const width: number = building.width
const height: number = building.height

Each building positions

building.each(callback: (position: Position) => void)

Remove building from path

building.remove()

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Example

const city = new City({
  width: 200,
  height: 200,
});

city.generate({
  streetMinLength: 15,
}).then(() => {
  // Draw roads
  ctx.beginPath();
  city.getAllPaths().forEach((path) => {
    const positions = path.getPositions();
    ctx.moveTo(positions.beg.x, positions.beg.y);
    ctx.lineTo(positions.end.x, positions.end.y);
  });
  ctx.stroke();

  // Draw buildings
  city.getAllBuildings().forEach((building) => {
    ctx.fillRect(
      building.position.x,
      building.position.y,
      building.width,
      building.height
    );
  });
});