rsc-path-finder

generate paths between points on a runescape classic map. each tile is expanded into a 2x2 grid of booleans describing how the tile is blocked. this allows for horizontal, vertical and fully-blocked tile representation (diagonal walls are completely impassbale). once a path is found, the steps are smoothed and converted to game coordinates.

this module is safe to use in a game loop as the computation is asynchronous.

path from Lumbridge to the Legend's Guild

path from Al Kharid to Bandit Camp

path to Tree Gnome Village entrance

install

$ npm install @2003scape/rsc-path-finder

example

const fs = require('fs');
const { gunzipSync } = require('zlib');
const { Config } = require('@2003scape/rsc-config');
const { Landscape } = require('@2003scape/rsc-landscape');
const { PathFinder } = require('./src');

const config = new Config();
config.loadArchive(fs.readFileSync('./config85.jag'));

const landscape = new Landscape();
landscape.loadJag(fs.readFileSync('./land63.jag'),
    fs.readFileSync('./maps63.jag'));
landscape.loadMem(fs.readFileSync('./land63.mem'),
    fs.readFileSync('./maps63.mem'));
landscape.parseArchives();

const pathFinder = new PathFinder(config, landscape);
const objectLocations =
    JSON.parse(gunzipSync(fs.readFileSync('./object-locs.json.gz')));
objectLocations.forEach(obj => pathFinder.addObject(obj));

const wallObjectLocations = require('./wallObject-locs');
wallObjectLocations.forEach(obj => pathFinder.addWallObject(obj));

// replace the taverly gate with an open gate
pathFinder.addObject({ id: 58, x: 341, y: 487, direction: 4 });

// close the door in gertrude's house
pathFinder.addWallObject({ id: 2, x: 163, y: 513, direction: 1 });
// open it again
// pathFinder.addWallObject({ id: 1, x: 163, y: 513, direction: 1 });

pathFinder.start();

(async () => {
    const path = await pathFinder.findPath(
        { x: 126, y: 655 },
        { x: 513, y: 552 });
        //{ x: 72, y: 694 },
        //{ x: 320, y: 290 });
        //{ x: 672, y: 718 },
        //{ x: 634, y: 706 });
        //{ x: 138, y: 1594 },
        //{ x: 131, y: 1602 });
    console.log('found path to legends guild', path.length);

    fs.writeFileSync('./legends-path.png',
        pathFinder.toCanvas(path).toBuffer());

    pathFinder.stop();
})();

api

pathFinder = new PathFinder(config, landscape, tickRate = 80)

create a new pathfinding instance.

config in the first argument must contain definitions of game and wall objects with at least the following:

{
    // definitions for game objects (tree, altar, furnace, etc.)
    objects: [
        {
            type: 'unblocked' || 'blocked || 'closed-door' || 'open-door',
            width: Number,
            height: Number
        },
        // ...
    ],
    // definitions for wall objects (doors, walls, boundaries, etc.)
    wallObjects: [
        {
            blocked: true || false,
        }
        // ...
    ]
    // definitions for tiles (floors, water, roads, etc.)
    tiles: [
        {
            blocked: true || false,
        }
        // ...
    ]
}

objects, wallObjects and tiles are all members of an rsc-config instance.

landscape is an instance of rsc-landscape.

tickRate is how often (in ms) to poll for new paths to find when findPath isn't active.

pathFinder.addObject({ id, x, y, direction })

add game object to position. id corresponds to index in config.objects. if open-door or closed-door type objects are added, replace them with door wall objects.

pathFinder.addWallObject({ id, x, y, direction })

add wall object to position. id corresponds to index in config.wallObjects array. if an unblocked wall object is added, remove any existing obstacles (door with doorframes, spider web with blank, etc.).

pathFinder.start()

pathFinder.stop()

enable and disable the pathfinding run loop.

async pathFinder.findPath({ x, y }, { x, y })

find a path between startPos and endPos. returns an array of game coordinates.

pathFinder.isValidGameStep({ x, y }, { deltaX, deltaY })

return true if we can step from startPos in the step direction.

pathFinder.getLineOfSight({ x, y }, { x, y })

find a direct diagonal beeline path between two points.

pathFinder.toCanvas(path = undefined)

create a canvas with all of the obstacles filled in with white. if path is specified, fill the path tiles with red.

license

Copyright 2020 2003Scape Team

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License along with this program. If not, see http://www.gnu.org/licenses/.