Add support for gridless pathfinding

js/api.js

@@ -0,0 +1,181 @@
+import {measureDistances} from "./compatibility.js";
+import {getMovementHistory} from "./movement_tracking.js";
+import {GenericSpeedProvider, SpeedProvider} from "./speed_provider.js"
+import {settingsKey} from "./settings.js"
+import {getTokenShape} from "./util.js";
+
+export const availableSpeedProviders = {}
+export let currentSpeedProvider = undefined
+
+function register(module, type, speedProvider) {
+	const id = `${type}.${module.id}`
+	let providerInstance
+	if (speedProvider.prototype instanceof SpeedProvider) {
+		providerInstance = new speedProvider(id)
+	}
+	else {
+		console.warn(`Drag Ruler | The ${type} '${module.id}' uses the old, deprecated version of the Drag Ruler API. ` +
+		             "That old API will be removed in a future Drag Ruler version. " +
+		             `Please update the ${type} ${module.id} to stay compatible with future Drag Ruler versions.`);
+		speedProvider.id = id
+		speedProvider.usesRuler = () => true
+		providerInstance = speedProvider
+	}
+	setupProvider(providerInstance)
+}
+
+function setupProvider(speedProvider) {
+	if (speedProvider instanceof SpeedProvider) {
+		const unreachableColor = {id: "unreachable", default: speedProvider.defaultUnreachableColor, name: "drag-ruler.settings.speedProviderSettings.color.unreachable.name"}
+		for (const color of speedProvider.colors.concat([unreachableColor])) {
+			game.settings.register(settingsKey, `speedProviders.${speedProvider.id}.color.${color.id}`, {
+				config: false,
+				scope: "client",
+				type: Number,
+				default: color.default,
+			})
+		}
+		for (const setting of speedProvider.settings) {
+			setting.config = false
+			game.settings.register(settingsKey, `speedProviders.${speedProvider.id}.setting.${setting.id}`, setting)
+		}
+	}
+
+	availableSpeedProviders[speedProvider.id] = speedProvider
+	game.settings.settings.get("drag-ruler.speedProvider").default = getDefaultSpeedProvider()
+	updateSpeedProvider()
+}
+
+export function getDefaultSpeedProvider() {
+	const providerIds = Object.keys(availableSpeedProviders)
+	// Game systems take the highest precedence for the being the default
+	const gameSystem = providerIds.find(key => key.startsWith("system."))
+	if (gameSystem)
+		return gameSystem
+
+	// If no game system is registered modules are next up.
+	// For lack of a method to select the best module we're just falling back to taking the next best module
+	// settingKeys should always be sorted the same way so this should achive a stable default
+	const module = providerIds.find(key => key.startsWith("module."))
+	if (module)
+		return module
+
+	// If neither a game system or a module is found fall back to the native implementation
+	return providerIds[0]
+}
+
+export function updateSpeedProvider() {
+	// If the configured provider is registered use that one. If not use the default provider
+	const configuredProvider = game.settings.get("drag-ruler", "speedProvider")
+	currentSpeedProvider = availableSpeedProviders[configuredProvider] ?? availableSpeedProviders[game.settings.settings.get("drag-ruler.speedProvider").default]
+}
+
+export function initApi() {
+	const genericSpeedProviderInstance = new GenericSpeedProvider("native")
+	setupProvider(genericSpeedProviderInstance)
+}
+
+export function getRangesFromSpeedProvider(token) {
+	try {
+		if (currentSpeedProvider instanceof Function)
+			return currentSpeedProvider(token, 0x00FF00)
+		const ranges = currentSpeedProvider.getRanges(token)
+		for (const range of ranges) {
+			range.color = game.settings.get(settingsKey, `speedProviders.${currentSpeedProvider.id}.color.${range.color}`)
+		}
+		return ranges
+	}
+	catch (e) {
+		console.error(e)
+		return []
+	}
+}
+
+export function getUnreachableColorFromSpeedProvider() {
+	if (currentSpeedProvider instanceof Function)
+		return 0xFF0000
+	try {
+		return game.settings.get(settingsKey, `speedProviders.${currentSpeedProvider.id}.color.unreachable`)
+	}
+	catch (e) {
+		console.error(e)
+		return 0xFF0000
+	}
+}
+
+export function getCostFromSpeedProvider(token, area, options) {
+	try {
+		if (currentSpeedProvider instanceof Function) {
+			return SpeedProvider.prototype.getCostForStep.call(undefined, token, area, options);
+		}
+		return currentSpeedProvider.getCostForStep(token, area, options);
+	}
+	catch (e) {
+		console.error(e);
+		return 1;
+	}
+}
+
+export function getColorForDistanceAndToken(distance, token, ranges=null) {
+	if (!ranges) {
+		ranges = getRangesFromSpeedProvider(token);
+	}
+	if (ranges.length === 0)
+		return null;
+	const currentRange = ranges.reduce((minRange, currentRange) => {
+		if (distance <= currentRange.range && currentRange.range < minRange.range)
+			return currentRange;
+		return minRange;
+	}, {range: Infinity, color: getUnreachableColorFromSpeedProvider()});
+	return currentRange.color;
+}
+
+export function getMovedDistanceFromToken(token) {
+	const terrainRulerAvailable = game.modules.get("terrain-ruler")?.active;
+	const history = getMovementHistory(token);
+	const segments = Ruler.dragRulerGetRaysFromWaypoints(history, {x: token.x, y: token.y}).map(ray => {return {ray}});
+	const shape = getTokenShape(token);
+	const distances = measureDistances(segments, token, shape, {enableTerrainRuler: terrainRulerAvailable});
+	// Sum up the distances
+	return distances.reduce((acc, val) => acc + val, 0);
+}
+
+export function registerModule(moduleId, speedProvider) {
+	// Check if a module with the given id exists and is currently enabled
+	const module = game.modules.get(moduleId)
+	// If it doesn't the calling module did something wrong. Log a warning and ignore this module
+	if (!module) {
+		console.warn(
+			`Drag Ruler | A module tried to register with the id "${moduleId}". However no active module with this id was found.` +
+			"This api registration call was ignored. " +
+			"If you are the author of that module please check that the id passed to `registerModule` matches the id in your manifest exactly." +
+			"If this call was made form a game system instead of a module please use `registerSystem` instead.")
+		return
+	}
+	// Using Drag Ruler's id is not allowed
+	if (moduleId === "drag-ruler") {
+		console.warn(
+			`Drag Ruler | A module tried to register with the id "${moduleId}", which is not allowed. This api registration call was ignored. ` +
+			"If you're the author of the module please use the id of your own module as it's specified in your manifest to register to this api. " +
+			"If this call was made form a game system instead of a module please use `registerSystem` instead."
+		)
+		return
+	}
+
+	register(module, "module", speedProvider)
+}
+
+export function registerSystem(systemId, speedProvider) {
+	const system = game.system
+	// If the current system id doesn't match the provided id something went wrong. Log a warning and ignore this module
+	if (system.id != systemId) {
+		console.warn(
+			`Drag Ruler | A system tried to register with the id "${systemId}". However the active system has a different id.` +
+			"This api registration call was ignored. " +
+			"If you are the author of that system please check that the id passed to `registerSystem` matches the id in your manifest exactly." +
+			"If this call was made form a module instead of a game system please use `registerModule` instead.")
+		return
+	}
+
+	register(system, "system", speedProvider)
+}

js/compatibility.js

@@ -0,0 +1,89 @@
+import {getCostFromSpeedProvider} from "./api.js";
+import {settingsKey} from "./settings.js";
+import {getAreaFromPositionAndShape, highlightTokenShape} from "./util.js";
+
+export function getHexSizeSupportTokenGridCenter(token) {
+	const tokenCenterOffset = CONFIG.hexSizeSupport.getCenterOffset(token)
+	return {x: token.x + tokenCenterOffset.x, y: token.y + tokenCenterOffset.y}
+}
+
+export function highlightMeasurementTerrainRuler(ray, startDistance, tokenShape=[{x: 0, y: 0}], alpha=1) {
+	for (const space of ray.terrainRulerVisitedSpaces.reverse()) {
+		const color = this.dragRulerGetColorForDistance(startDistance + space.distance);
+		highlightTokenShape.call(this, space, tokenShape, color, alpha)
+	}
+}
+
+export function measureDistances(segments, entity, shape, options={}) {
+	const opts = duplicate(options)
+	if (canvas.grid.diagonalRule === "EUCL") {
+		opts.ignoreGrid = true;
+		opts.gridSpaes = false;
+	}
+	if (opts.enableTerrainRuler) {
+		opts.gridSpaces = true;
+		const firstNewSegmentIndex = segments.findIndex(segment => !segment.ray.dragRulerVisitedSpaces);
+		const previousSegments = segments.slice(0, firstNewSegmentIndex);
+		const newSegments = segments.slice(firstNewSegmentIndex);
+		const distances = previousSegments.map(segment => segment.ray.dragRulerVisitedSpaces[segment.ray.dragRulerVisitedSpaces.length - 1].distance);
+		previousSegments.forEach(segment => segment.ray.terrainRulerVisitedSpaces = duplicate(segment.ray.dragRulerVisitedSpaces));
+		opts.costFunction = (x, y, costOptions={}) => {	return getCostFromSpeedProvider(entity, getAreaFromPositionAndShape({x, y}, shape), costOptions); }
+		if (previousSegments.length > 0)
+			opts.terrainRulerInitialState = previousSegments[previousSegments.length - 1].ray.dragRulerFinalState;
+		return distances.concat(terrainRuler.measureDistances(newSegments, opts));
+	}
+	else {
+		// If another module wants to enable grid measurements but disable grid highlighting,
+		// manually set the *duplicate* option's gridSpaces value to true for the Foundry logic to work properly
+		if(!opts.ignoreGrid) {
+			opts.gridSpaces = true;
+		}
+		return canvas.grid.measureDistances(segments, opts);
+	}
+}
+
+export function checkDependencies() {
+	if (!game.modules.get("socketlib")?.active) {
+		console.error("Drag Ruler | The `socketlib` module isn't enabled, but it's required for Drag Ruler to operate properly.");
+		if (game.user.isGM) {
+			new Dialog({
+				title: game.i18n.localize("drag-ruler.dependencies.socketlib.title"),
+				content: `<h2>${game.i18n.localize("drag-ruler.dependencies.socketlib.title")}</h2><p>${game.i18n.localize("drag-ruler.dependencies.socketlib.text")}</p>`,
+				buttons: {
+					ok: {
+						icon: '<i class="fas fa-check"></i>',
+						label: game.i18n.localize("drag-ruler.dependencies.ok")
+					}
+				},
+			}).render(true);
+		}
+	}
+	else if (!game.modules.get("terrain-ruler")?.active && game.user.isGM && !game.settings.get(settingsKey, "neverShowTerrainRulerHint")) {
+		const lastHint = game.settings.get(settingsKey, "lastTerrainRulerHintTime");
+		if (Date.now() - lastHint > 604800000) { // One week
+			let enabledTerrainModule;
+			if (game.modules.get("enhanced-terrain-layer")?.active) {
+				enabledTerrainModule = game.modules.get("enhanced-terrain-layer").data.title;
+			}
+			if (enabledTerrainModule) {
+				new Dialog({
+					title: game.i18n.localize("drag-ruler.dependencies.terrain-ruler.title"),
+					content: `<h2>${game.i18n.localize("drag-ruler.dependencies.terrain-ruler.title")}</h2><p>${game.i18n.format("drag-ruler.dependencies.terrain-ruler.text", {moduleName: enabledTerrainModule})}</p>`,
+					buttons: {
+						ok: {
+							icon: '<i class="fas fa-check"></i>',
+							label: game.i18n.localize("drag-ruler.dependencies.ok"),
+							callback: () => game.settings.set(settingsKey, "lastTerrainRulerHintTime", Date.now()),
+						},
+						neverShowAgain: {
+							icon: '<i class="fas fa-times"></i>',
+							label: game.i18n.localize("drag-ruler.dependencies.terrain-ruler.neverShowAgain"),
+							callback: () => game.settings.set(settingsKey, "neverShowTerrainRulerHint", true),
+						}
+					},
+					close: () => game.settings.set(settingsKey, "lastTerrainRulerHintTime", Date.now())
+				}).render(true);
+			}
+		}
+	}
+}

js/foundry_fixes.js

@@ -0,0 +1,36 @@
+// Wrapper to fix a FoundryVTT bug that causes the return values of canvas.grid.grid.getPixelsFromGridPosition to be ordered inconsistently
+
+// https://gitlab.com/foundrynet/foundryvtt/-/issues/4705
+export function getPixelsFromGridPosition(xGrid, yGrid) {
+	if (canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS) {
+		return canvas.grid.grid.getPixelsFromGridPosition(yGrid, xGrid)
+	}
+	return canvas.grid.grid.getPixelsFromGridPosition(xGrid, yGrid)
+}
+
+// Wrapper to fix a FoundryVTT bug that causes the return values of canvas.grid.grid.getPixelsFromGridPosition to be ordered inconsistently
+// https://gitlab.com/foundrynet/foundryvtt/-/issues/4705
+export function getGridPositionFromPixels(xPixel, yPixel) {
+	const [x, y] = canvas.grid.grid.getGridPositionFromPixels(xPixel, yPixel)
+	if (canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS)
+		return [y, x]
+	return [x, y]
+}
+
+export function getGridPositionFromPixelsObj(o) {
+	const r = {};
+	[r.x, r.y] = getGridPositionFromPixels(o.x, o.y);
+	return r;
+}
+
+export function getPixelsFromGridPositionObj(o) {
+	const r = {};
+	[r.x, r.y] = getPixelsFromGridPosition(o.x, o.y);
+	return r;
+}
+
+export function getCenterFromGridPositionObj(o) {
+	const r = getPixelsFromGridPositionObj(o);
+	[r.x, r.y] = canvas.grid.getCenter(r.x, r.y);
+	return r;
+}

js/foundry_imports.js

@@ -0,0 +1,369 @@
+import {highlightMeasurementTerrainRuler, measureDistances} from "./compatibility.js";
+import {getGridPositionFromPixels, getGridPositionFromPixelsObj, getPixelsFromGridPositionObj} from "./foundry_fixes.js";
+import {Line} from "./geometry.js";
+import {disableSnap, moveWithoutAnimation} from "./keybindings.js";
+import {trackRays} from "./movement_tracking.js"
+import {findPath, isPathfindingEnabled} from "./pathfinding.js";
+import {settingsKey} from "./settings.js";
+import {recalculate} from "./socket.js";
+import {applyTokenSizeOffset, enumeratedZip, getSnapPointForEntity, getSnapPointForToken, getSnapPointForTokenObj, getTokenShape, highlightTokenShape, sum} from "./util.js";
+
+// This is a modified version of Ruler.moveToken from foundry 0.7.9
+export async function moveEntities(draggedEntity, selectedEntities) {
+	let wasPaused = game.paused;
+	if (wasPaused && !game.user.isGM) {
+		ui.notifications.warn(game.i18n.localize("GAME.PausedWarning"));
+		return false;
+	}
+	if (!this.visible || !this.destination) return false;
+	if (!draggedEntity) return;
+
+	// Wait until all scheduled measurements are done
+	await this.deferredMeasurementPromise;
+
+	// Get the movement rays and check collision along each Ray
+	// These rays are center-to-center for the purposes of collision checking
+	const rays = this.constructor.dragRulerGetRaysFromWaypoints(this.waypoints, this.destination);
+	if (!game.user.isGM && draggedEntity instanceof Token) {
+		const hasCollision = selectedEntities.some(token => {
+			const offset = calculateEntityOffset(token, draggedEntity);
+			const offsetRays = rays.filter(ray => !ray.isPrevious).map(ray => applyOffsetToRay(ray, offset))
+			return offsetRays.some(r => canvas.walls.checkCollision(r));
+		})
+		if (hasCollision) {
+			ui.notifications.error(game.i18n.localize("ERROR.TokenCollide"));
+			this._endMeasurement();
+			return true;
+		}
+	}
+
+	// Execute the movement path.
+	// Transform each center-to-center ray into a top-left to top-left ray using the prior token offsets.
+	this._state = Ruler.STATES.MOVING;
+	await animateEntities.call(this, selectedEntities, draggedEntity, rays, wasPaused);
+
+	// Once all animations are complete we can clear the ruler
+	if (this.draggedEntity?.id === draggedEntity.id)
+		this._endMeasurement();
+}
+
+// This is a modified version code extracted from Ruler.moveToken from foundry 0.7.9
+async function animateEntities(entities, draggedEntity, draggedRays, wasPaused) {
+	const newRays = draggedRays.filter(r => !r.isPrevious);
+	const entityAnimationData = entities.map(entity => {
+		const entityOffset = calculateEntityOffset(entity, draggedEntity);
+		const offsetRays = newRays.map(ray => applyOffsetToRay(ray, entityOffset));
+
+		// Determine offset relative to the Token top-left.
+		// This is important so we can position the token relative to the ruler origin for non-1x1 tokens.
+		const firstWaypoint = this.waypoints.find(w => !w.isPrevious);
+		const origin = [firstWaypoint.x + entityOffset.x, firstWaypoint.y + entityOffset.y];
+		let dx, dy;
+		if (canvas.grid.type === CONST.GRID_TYPES.GRIDLESS) {
+			dx = entity.data.x - origin[0];
+			dy = entity.data.y - origin[1];
+		}
+		else {
+			dx = entity.data.x - origin[0];
+			dy = entity.data.y - origin[1];
+		}
+
+		return {entity, rays: offsetRays, dx, dy};
+	});
+
+	const isToken = draggedEntity instanceof Token;
+	const animate = isToken && !moveWithoutAnimation;
+	const startWaypoint = animate ? 0 : entityAnimationData[0].rays.length - 1;
+
+	// This is a flag of the "Monk's Active Tile Triggers" module that signals that the movement should be cancelled early
+	this.cancelMovement = false;
+
+	for (let i = startWaypoint;i < entityAnimationData[0].rays.length; i++) {
+		if (!wasPaused && game.paused) break;
+		const entityPaths = entityAnimationData.map(({entity, rays, dx, dy}) => {
+			const ray = rays[i];
+			const dest = [ray.B.x, ray.B.y];
+			const path = new Ray({x: entity.x, y: entity.y}, {x: dest[0] + dx, y: dest[1] + dy});
+			return {entity, path};
+		});
+		const updates = entityPaths.map(({entity, path}) => {
+			return {x: path.B.x, y: path.B.y, _id: entity.id};
+		});
+		await draggedEntity.scene.updateEmbeddedDocuments(draggedEntity.constructor.embeddedName, updates, {animate});
+		if (animate)
+			await Promise.all(entityPaths.map(({entity}) => CanvasAnimation.getAnimation(entity.movementAnimationName)?.promise));
+
+		// This is a flag of the "Monk's Active Tile Triggers" module that signals that the movement should be cancelled early
+		if (this.cancelMovement) {
+			entityAnimationData.forEach(ead => ead.rays = ead.rays.slice(0, i + 1));
+			break;
+		}
+	}
+	if (isToken)
+		trackRays(entities, entityAnimationData.map(({rays}) => rays)).then(() => recalculate(entities));
+}
+
+function calculateEntityOffset(entityA, entityB) {
+	return {x: entityA.data.x - entityB.data.x, y: entityA.data.y - entityB.data.y};
+}
+
+function applyOffsetToRay(ray, offset) {
+	const newRay = new Ray({x: ray.A.x + offset.x, y: ray.A.y + offset.y}, {x: ray.B.x + offset.x, y: ray.B.y + offset.y});
+	newRay.isPrevious = ray.isPrevious;
+	return newRay;
+}
+
+// This is a modified version of Ruler._onMouseMove from foundry 0.7.9
+export function onMouseMove(event) {
+	if (this._state === Ruler.STATES.MOVING) return;
+
+	// Extract event data
+	const destination = {x: event.data.destination.x + this.rulerOffset.x, y: event.data.destination.y + this.rulerOffset.y}
+
+	// Hide any existing Token HUD
+	canvas.hud.token.clear();
+	delete event.data.hudState;
+
+	// Draw measurement updates
+	scheduleMeasurement.call(this, destination, event);
+}
+
+function scheduleMeasurement(destination, event) {
+	const measurementInterval = 50;
+	const mt = event._measureTime || 0;
+	const originalEvent = event.data.originalEvent;
+	if (Date.now() - mt > measurementInterval) {
+		this.measure(destination, {snap: !disableSnap});
+		event._measureTime = Date.now();
+		this._state = Ruler.STATES.MEASURING;
+		cancelScheduledMeasurement.call(this);
+	}
+	else {
+		this.deferredMeasurementData = {destination, event};
+		if (!this.deferredMeasurementTimeout) {
+			this.deferredMeasurementPromise = new Promise((resolve, reject) => this.deferredMeasurementResolve = resolve);
+			this.deferredMeasurementTimeout = window.setTimeout(() => scheduleMeasurement.call(this, this.deferredMeasurementData.destination, this.deferredMeasurementData.event), measurementInterval);
+		}
+	}
+}
+
+export function cancelScheduledMeasurement() {
+	window.clearTimeout(this.deferredMeasurementTimeout);
+	this.deferredMeasurementTimeout = undefined;
+	this.deferredMeasurementResolve?.();
+}
+
+// This is a modified version of Ruler.measure form foundry 0.7.9
+export function measure(destination, options={}) {
+
+	const isToken = this.draggedEntity instanceof Token;
+	if (isToken && !this.draggedEntity.isVisible)
+		return []
+
+	options.snap = options.snap ?? !disableSnap;
+
+	if (options.snap) {
+		destination = getSnapPointForEntity(destination.x, destination.y, this.draggedEntity);
+	}
+
+	this.dragRulerRemovePathfindingWaypoints();
+
+	if (isToken && isPathfindingEnabled.call(this)) {
+		const from = getGridPositionFromPixelsObj(this.waypoints[this.waypoints.length - 1]);
+		const to = getGridPositionFromPixelsObj(destination);
+		let path = findPath(from, to, this.draggedEntity, this.waypoints);
+		if (path) {
+			path = path.map(point => getSnapPointForTokenObj(getPixelsFromGridPositionObj(point), this.draggedEntity));
+
+			// If the token is snapped to the grid, the first point of the path is already handled by the ruler
+			if (path[0].x === this.waypoints[this.waypoints.length - 1].x && path[0].y === this.waypoints[this.waypoints.length - 1].y)
+				path = path.slice(1);
+
+			// If snapping is enabled, the last point of the path is already handled by the ruler
+			if (options.snap)
+				path = path.slice(0, path.length - 1);
+
+			for (const point of path) {
+				point.isPathfinding = true;
+				this.labels.addChild(new PreciseText("", CONFIG.canvasTextStyle));
+			}
+			this.waypoints = this.waypoints.concat(path);
+		}
+		else {
+			// Don't show a path if the pathfinding yields no result to show the user that the destination is unreachable
+			destination = this.waypoints[this.waypoints.length - 1];
+		}
+	}
+
+	if(options.gridSpaces === undefined) {
+		options.gridSpaces = canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS;
+	}
+
+	if (canvas.grid.diagonalRule === "EUCL") {
+		options.gridSpaces = false;
+		options.ignoreGrid = true;
+	}
+
+	if(options.ignoreGrid === undefined) {
+		options.ignoreGrid = false;
+	}
+
+	options.enableTerrainRuler = isToken && game.modules.get("terrain-ruler")?.active;
+
+	const waypoints = this.waypoints.concat([destination]);
+	// Move the waypoints to the center of the grid if a size is used that measures from edge to edge
+	const centeredWaypoints = isToken ? applyTokenSizeOffset(waypoints, this.draggedEntity) : duplicate(waypoints);
+	// Foundries native ruler requires the waypoints to sit in the dead center of the square to work properly
+	if (!options.enableTerrainRuler && !options.ignoreGrid)
+		centeredWaypoints.forEach(w => [w.x, w.y] = canvas.grid.getCenter(w.x, w.y));
+
+	const r = this.ruler;
+	this.destination = destination;
+
+	// Iterate over waypoints and construct segment rays
+	const segments = [];
+	const centeredSegments = []
+	for (let [i, dest] of waypoints.slice(1).entries()) {
+		const centeredDest = centeredWaypoints[i + 1]
+		const origin = waypoints[i];
+		const centeredOrigin = centeredWaypoints[i]
+		const label = this.labels.children[i];
+		const ray = new Ray(origin, dest);
+		const centeredRay = new Ray(centeredOrigin, centeredDest)
+		ray.isPrevious = Boolean(origin.isPrevious);
+		centeredRay.isPrevious = ray.isPrevious;
+		ray.dragRulerVisitedSpaces = origin.dragRulerVisitedSpaces;
+		centeredRay.dragRulerVisitedSpaces = ray.dragRulerVisitedSpaces;
+		ray.dragRulerFinalState = origin.dragRulerFinalState;
+		centeredRay.dragRulerFinalState = ray.dragRulerFinalState;
+		if (ray.distance < 10) {
+			if (label) label.visible = false;
+			continue;
+		}
+		segments.push({ ray, label });
+		centeredSegments.push({ray: centeredRay, label})
+	}
+
+
+	const shape = isToken ? getTokenShape(this.draggedEntity) : null;
+
+	// Compute measured distance
+	const distances = measureDistances(centeredSegments, this.draggedEntity, shape, options);
+
+	let totalDistance = 0;
+	for (let [i, d] of distances.entries()) {
+		let s = centeredSegments[i];
+		s.startDistance = totalDistance
+		totalDistance += d;
+		s.last = i === (centeredSegments.length - 1);
+		s.distance = d;
+		s.text = this._getSegmentLabel(d, totalDistance, s.last);
+	}
+
+	// Clear the grid highlight layer
+	const hlt = canvas.grid.highlightLayers[this.name] || canvas.grid.addHighlightLayer(this.name);
+	hlt.clear();
+
+	// Draw measured path
+	r.clear();
+	let rulerColor
+	if (!options.gridSpaces || canvas.grid.type === CONST.GRID_TYPES.GRIDLESS)
+		rulerColor = this.dragRulerGetColorForDistance(totalDistance);
+	else
+		rulerColor = this.color
+	for (const [i, s, cs] of enumeratedZip([...segments].reverse(), [...centeredSegments].reverse())) {
+		const { label, text, last } = cs;
+
+		// Draw line segment
+		const opacityMultiplier = s.ray.isPrevious ? 0.33 : 1;
+		r.lineStyle(6, 0x000000, 0.5 * opacityMultiplier).moveTo(s.ray.A.x, s.ray.A.y).lineTo(s.ray.B.x, s.ray.B.y)
+			.lineStyle(4, rulerColor, 0.25 * opacityMultiplier).moveTo(s.ray.A.x, s.ray.A.y).lineTo(s.ray.B.x, s.ray.B.y);
+
+		// Draw the distance label just after the endpoint of the segment
+		if (label) {
+			label.text = text;
+			label.alpha = last ? 1.0 : 0.5;
+			label.visible = true;
+			let labelPosition = {x: s.ray.x0, y: s.ray.y0};
+			labelPosition.x -= label.width / 2;
+			labelPosition.y -= label.height / 2;
+			const rayLine = Line.fromPoints(s.ray.A, s.ray.B);
+			const rayLabelXHitY = rayLine.calcY(labelPosition.x);
+			let innerDistance;
+			// If ray hits top or bottom side of label
+			if (rayLine.isVertical || rayLabelXHitY < labelPosition.y || rayLabelXHitY > labelPosition.y + label.height)
+				innerDistance = Math.abs((label.height / 2) / Math.sin(s.ray.angle));
+			// If ray hits left or right side of label
+			else
+				innerDistance = Math.abs((label.width / 2) / Math.cos(s.ray.angle));
+			labelPosition = s.ray.project((s.ray.distance + 50 + innerDistance) / s.ray.distance);
+			labelPosition.x -= label.width / 2;
+			labelPosition.y -= label.height / 2;
+			label.position.set(labelPosition.x, labelPosition.y);
+		}
+
+		// Highlight grid positions
+		if (isToken && canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS && options.gridSpaces) {
+			if (options.enableTerrainRuler) {
+				highlightMeasurementTerrainRuler.call(this, cs.ray, cs.startDistance, shape, opacityMultiplier)
+			}
+			else {
+				const previousSegments = centeredSegments.slice(0, segments.length - 1 - i);
+				highlightMeasurementNative.call(this, cs.ray, previousSegments, shape, opacityMultiplier);
+			}
+		}
+	}
+
+	// Draw endpoints
+	for (let p of waypoints) {
+		r.lineStyle(2, 0x000000, 0.5).beginFill(rulerColor, 0.25).drawCircle(p.x, p.y, 8);
+	}
+
+	// Return the measured segments
+	return segments;
+}
+
+export function highlightMeasurementNative(ray, previousSegments, tokenShape=[{x: 0, y: 0}], alpha=1) {
+	const spacer = canvas.scene.data.gridType === CONST.GRID_TYPES.SQUARE ? 1.41 : 1;
+	const nMax = Math.max(Math.floor(ray.distance / (spacer * Math.min(canvas.grid.w, canvas.grid.h))), 1);
+	const tMax = Array.fromRange(nMax+1).map(t => t / nMax);
+
+	// Track prior position
+	let prior = null;
+
+	// Iterate over ray portions
+	for ( let [i, t] of tMax.reverse().entries() ) {
+		let {x, y} = ray.project(t);
+
+		// Get grid position
+		let [x0, y0] = (i === 0) ? [null, null] : prior;
+		let [x1, y1] = canvas.grid.grid.getGridPositionFromPixels(x, y);
+		if ( x0 === x1 && y0 === y1 ) continue;
+
+		// Highlight the grid position
+		let [xg, yg] = canvas.grid.grid.getPixelsFromGridPosition(x1, y1);
+		const pathUntilSpace = previousSegments.concat([{ray: new Ray(ray.A, {x: xg, y: yg})}]);
+		const distance = sum(canvas.grid.measureDistances(pathUntilSpace, {gridSpaces: true}));
+		const color = this.dragRulerGetColorForDistance(distance);
+		const snapPoint = getSnapPointForToken(...canvas.grid.getTopLeft(x, y), this.draggedEntity);
+		const [snapX, snapY] = getGridPositionFromPixels(snapPoint.x + 1, snapPoint.y + 1);
+
+		prior = [x1, y1];
+
+		// If the positions are not neighbors, also highlight their halfway point
+		if (i > 0 && !canvas.grid.isNeighbor(x0, y0, x1, y1)) {
+			let th = tMax[i - 1] - (0.5 / nMax);
+			let {x, y} = ray.project(th);
+			let [x1h, y1h] = canvas.grid.grid.getGridPositionFromPixels(x, y);
+			let [xgh, ygh] = canvas.grid.grid.getPixelsFromGridPosition(x1h, y1h);
+			const pathUntilSpace = previousSegments.concat([{ray: new Ray(ray.A, {x: xgh, y: ygh})}]);
+			const distance = sum(canvas.grid.measureDistances(pathUntilSpace, {gridSpaces: true}));
+			const color = this.dragRulerGetColorForDistance(distance);
+			const snapPoint = getSnapPointForToken(...canvas.grid.getTopLeft(x, y), this.draggedEntity);
+			const [snapX, snapY] = getGridPositionFromPixels(snapPoint.x + 1, snapPoint.y + 1);
+			highlightTokenShape.call(this, {x: snapX, y: snapY}, tokenShape, color, alpha);
+		}
+
+		highlightTokenShape.call(this, {x: snapX, y: snapY}, tokenShape, color, alpha);
+	}
+}

js/geometry.js

@@ -0,0 +1,21 @@
+export class Line {
+	constructor(m, b) {
+		this.m = m;
+		this.b = b;
+	}
+
+	static fromPoints(p1, p2) {
+		// Bring line into y=mx+b form
+		const m = (p1.y - p2.y) / (p1.x - p2.x);
+		const b = p1.y - m * p1.x;
+		return new Line(m, b);
+	}
+
+	get isVertical() {
+		return !isFinite(this.m);
+	}
+
+	calcY(x) {
+		return this.m * x + this.b;
+	}
+}

js/keybindings.js

@@ -0,0 +1,130 @@
+import {settingsKey} from "./settings.js";
+import {getMeasurePosition, setSnapParameterOnOptions} from "./util.js";
+
+export let disableSnap = false;
+export let moveWithoutAnimation = false;
+export let togglePathfinding = false;
+
+export function registerKeybindings() {
+	game.keybindings.register(settingsKey, "cancelDrag", {
+		name: "drag-ruler.keybindings.cancelDrag",
+		onDown: cancelDrag,
+		uneditable: [{
+			key: "Escape",
+		}],
+		precedence: -1,
+	});
+
+	game.keybindings.register(settingsKey, "createWaypoint", {
+		name: "drag-ruler.keybindings.createWaypoint",
+		onDown: handleCreateWaypoint,
+		editable: [{
+			key: "Space"
+		}],
+		precedence: -1,
+	});
+
+	game.keybindings.register(settingsKey, "deleteWaypoint", {
+		name: "drag-ruler.keybindings.deleteWaypoint",
+		onDown: handleDeleteWaypoint,
+		precedence: -1,
+	});
+
+	game.keybindings.register(settingsKey, "disableSnap", {
+		name: "drag-ruler.keybindings.disableSnap.name",
+		hint: "drag-ruler.keybindings.disableSnap.hint",
+		onDown: handleDisableSnap,
+		onUp: handleDisableSnap,
+		editable: [{
+			key: "ShiftLeft",
+		}],
+		precedence: -1,
+	});
+
+	game.keybindings.register(settingsKey, "moveWithoutAnimation", {
+		name: "drag-ruler.keybindings.moveWithoutAnimation.name",
+		hint: "drag-ruler.keybindings.moveWithoutAnimation.hint",
+		onDown: handleMoveWithoutAnimation,
+		onUp: handleMoveWithoutAnimation,
+		editable: [{
+			key: "AltLeft",
+		}],
+		precedence: -1,
+	});
+
+	game.keybindings.register(settingsKey, "togglePathfinding", {
+		name: "drag-ruler.keybindings.togglePathfinding.name",
+		hint: "drag-ruler.keybindings.togglePathfinding.hint",
+		onDown: handleTogglePathfinding,
+		onUp: handleTogglePathfinding,
+		precedence: -1,
+		restricted: !game.settings.get(settingsKey, "allowPathfinding"),
+	});
+}
+
+function handleDeleteWaypoint() {
+	const ruler = canvas.controls.ruler;
+	if (!ruler?.draggedEntity)
+		return false;
+	ruler.dragRulerDeleteWaypoint();
+	return true;
+}
+
+function handleCreateWaypoint() {
+	const ruler = canvas.controls.ruler;
+	// .draggedEntity is used here because .isDragRuler only returns true once the ruler started measuring
+	// Ruler can end up being undefined here if no canvas is active
+	if (!ruler?.draggedEntity)
+		return false;
+
+	let options = {};
+	setSnapParameterOnOptions(ruler, options);
+
+	if (ruler._state === Ruler.STATES.INACTIVE) {
+		ruler.dragRulerStart(options);
+	}
+	else {
+		ruler.dragRulerAddWaypoint(getMeasurePosition(), options);
+	}
+	return true;
+}
+
+function cancelDrag() {
+	const ruler = canvas.controls.ruler;
+	if (!ruler?.draggedEntity)
+		return false;
+	ruler.dragRulerAbortDrag();
+	return true;
+}
+
+function handleDisableSnap(event) {
+	disableSnap = !event.up;
+
+	const ruler = canvas.controls.ruler;
+	if (!ruler?.isDragRuler)
+		return false;
+	if (ruler._state !== Ruler.STATES.MEASURING)
+		return false;
+
+	ruler.measure(getMeasurePosition(), {snap: !disableSnap});
+	ruler.dragRulerSendState();
+	return false;
+}
+
+function handleMoveWithoutAnimation(event) {
+	moveWithoutAnimation = !event.up;
+}
+
+function handleTogglePathfinding(event) {
+	togglePathfinding = !event.up;
+
+	const ruler = canvas.controls.ruler;
+	if (!ruler?.isDragRuler)
+		return false;
+	if (ruler._state !== Ruler.STATES.MEASURING)
+		return false;
+
+	ruler.measure(getMeasurePosition(), {snap: !disableSnap});
+	ruler.dragRulerSendState();
+	return false;
+}

js/libwrapper_shim.js

@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: MIT
+// Copyright © 2021 fvtt-lib-wrapper Rui Pinheiro
+
+
+'use strict';
+
+// A shim for the libWrapper library
+export let libWrapper = undefined;
+
+export const VERSIONS       = [1,11,0];
+export const TGT_SPLIT_RE   = new RegExp("([^.[]+|\\[('([^'\\\\]|\\\\.)+?'|\"([^\"\\\\]|\\\\.)+?\")\\])", 'g');
+export const TGT_CLEANUP_RE = new RegExp("(^\\['|'\\]$|^\\[\"|\"\\]$)", 'g');
+
+// Main shim code
+Hooks.once('init', () => {
+	// Check if the real module is already loaded - if so, use it
+	if(globalThis.libWrapper && !(globalThis.libWrapper.is_fallback ?? true)) {
+		libWrapper = globalThis.libWrapper;
+		return;
+	}
+
+	// Fallback implementation
+	libWrapper = class {
+		static get is_fallback() { return true };
+
+		static get WRAPPER()  { return 'WRAPPER'  };
+		static get MIXED()    { return 'MIXED'    };
+		static get OVERRIDE() { return 'OVERRIDE' };
+
+		static register(package_id, target, fn, type="MIXED", {chain=undefined}={}) {
+			const is_setter = target.endsWith('#set');
+			target = !is_setter ? target : target.slice(0, -4);
+			const split = target.match(TGT_SPLIT_RE).map((x)=>x.replace(/\\(.)/g, '$1').replace(TGT_CLEANUP_RE,''));
+			const root_nm = split.splice(0,1)[0];
+
+			let obj, fn_name;
+			if(split.length == 0) {
+				obj = globalThis;
+				fn_name = root_nm;
+			}
+			else {
+				const _eval = eval;
+				fn_name = split.pop();
+				obj = split.reduce((x,y)=>x[y], globalThis[root_nm] ?? _eval(root_nm));
+			}
+
+			let iObj = obj;
+			let descriptor = null;
+			while(iObj) {
+				descriptor = Object.getOwnPropertyDescriptor(iObj, fn_name);
+				if(descriptor) break;
+				iObj = Object.getPrototypeOf(iObj);
+			}
+			if(!descriptor || descriptor?.configurable === false) throw `libWrapper Shim: '${target}' does not exist, could not be found, or has a non-configurable descriptor.`;
+
+			let original = null;
+			const wrapper = (chain ?? (type.toUpperCase?.() != 'OVERRIDE' && type != 3)) ? function() { return fn.call(this, original.bind(this), ...arguments); } : function() { return fn.apply(this, arguments); };
+
+			if(!is_setter) {
+				if(descriptor.value) {
+					original = descriptor.value;
+					descriptor.value = wrapper;
+				}
+				else {
+					original = descriptor.get;
+					descriptor.get = wrapper;
+				}
+			}
+			else {
+				if(!descriptor.set) throw `libWrapper Shim: '${target}' does not have a setter`;
+				original = descriptor.set;
+				descriptor.set = wrapper;
+			}
+
+			descriptor.configurable = true;
+			Object.defineProperty(obj, fn_name, descriptor);
+		}
+	}
+});

js/main.js

@@ -0,0 +1,258 @@
+"use strict"
+
+import {getColorForDistanceAndToken, getMovedDistanceFromToken, getRangesFromSpeedProvider, initApi, registerModule, registerSystem} from "./api.js";
+import {checkDependencies, getHexSizeSupportTokenGridCenter} from "./compatibility.js";
+import {moveEntities, onMouseMove} from "./foundry_imports.js"
+import {disableSnap, registerKeybindings} from "./keybindings.js";
+import {libWrapper} from "./libwrapper_shim.js";
+import {performMigrations} from "./migration.js"
+import {removeLastHistoryEntryIfAt, resetMovementHistory} from "./movement_tracking.js";
+import {wipePathfindingCache} from "./pathfinding.js";
+import {extendRuler} from "./ruler.js";
+import {registerSettings, RightClickAction, settingsKey} from "./settings.js"
+import {recalculate} from "./socket.js";
+import {SpeedProvider} from "./speed_provider.js"
+import {setSnapParameterOnOptions} from "./util.js";
+
+import initGridlessPathfinding, * as GridlessPathfinding from "../wasm/gridless_pathfinding.js"
+
+CONFIG.debug.dragRuler = false;
+export let debugGraphics = undefined;
+
+initGridlessPathfinding().then(() => {
+	Hooks.on("canvasInit", wipePathfindingCache);
+	Hooks.on("canvasReady", wipePathfindingCache);
+	Hooks.on("createWall", wipePathfindingCache);
+	Hooks.on("updateWall", wipePathfindingCache);
+	Hooks.on("deleteWall", wipePathfindingCache);
+});
+
+Hooks.once("init", () => {
+	registerSettings()
+	registerKeybindings()
+	initApi()
+	hookDragHandlers(Token);
+	hookDragHandlers(MeasuredTemplate);
+	libWrapper.register("drag-ruler", "TokenLayer.prototype.undoHistory", tokenLayerUndoHistory, "WRAPPER");
+
+	extendRuler();
+
+	window.dragRuler = {
+		getColorForDistanceAndToken,
+		getMovedDistanceFromToken,
+		registerModule,
+		registerSystem,
+		recalculate,
+		resetMovementHistory,
+	}
+})
+
+Hooks.once("ready", () => {
+	performMigrations()
+	checkDependencies();
+	Hooks.callAll("dragRuler.ready", SpeedProvider)
+	if (CONFIG.debug.dragRuler)
+		debugGraphics = canvas.controls.addChild(new PIXI.Container());
+})
+
+Hooks.on("canvasReady", () => {
+	canvas.controls.rulers.children.forEach(ruler => {
+		ruler.draggedEntity = null;
+		Object.defineProperty(ruler, "isDragRuler", {
+			get: function isDragRuler() {
+				return Boolean(this.draggedEntity) && this._state !== Ruler.STATES.INACTIVE;
+			}
+		})
+	})
+})
+
+Hooks.on("getCombatTrackerEntryContext", function (html, menu) {
+	const entry = {
+		name: "drag-ruler.resetMovementHistory",
+		icon: '<i class="fas fa-undo-alt"></i>',
+		callback: li => resetMovementHistory(ui.combat.viewed, li.data('combatant-id')),
+	};
+	menu.splice(1, 0, entry);
+});
+
+function forwardIfUnahndled(newFn) {
+	return function(oldFn, ...args) {
+		const eventHandled = newFn(...args);
+		if (!eventHandled)
+			oldFn(...args);
+	};
+}
+
+function hookDragHandlers(entityType) {
+	const entityName = entityType.name
+	libWrapper.register("drag-ruler", `${entityName}.prototype._onDragLeftStart`, onEntityLeftDragStart, "WRAPPER");
+	if (entityType === Token)
+		libWrapper.register("drag-ruler", `${entityName}.prototype._onDragLeftMove`, onEntityLeftDragMoveSnap, "WRAPPER");
+	else
+		libWrapper.register("drag-ruler", `${entityName}.prototype._onDragLeftMove`, onEntityLeftDragMove, "WRAPPER");
+	libWrapper.register("drag-ruler", `${entityName}.prototype._onDragLeftDrop`, forwardIfUnahndled(onEntityDragLeftDrop), "MIXED");
+	libWrapper.register("drag-ruler", `${entityName}.prototype._onDragLeftCancel`, forwardIfUnahndled(onEntityDragLeftCancel), "MIXED");
+}
+
+async function tokenLayerUndoHistory(wrapped) {
+	const historyEntry = this.history[this.history.length - 1];
+	const returnValue = await wrapped();
+	if (historyEntry.type === "update") {
+		for (const entry of historyEntry.data) {
+			const token = canvas.tokens.get(entry._id);
+			removeLastHistoryEntryIfAt(token, entry.x, entry.y);
+		}
+	}
+	return returnValue;
+}
+
+function onEntityLeftDragStart(wrapped, event) {
+	wrapped(event);
+	const isToken = this instanceof Token;
+	const ruler = canvas.controls.ruler
+	ruler.draggedEntity = this;
+	let entityCenter;
+	if (isToken && canvas.grid.isHex && game.modules.get("hex-size-support")?.active && CONFIG.hexSizeSupport.getAltSnappingFlag(this))
+		entityCenter = getHexSizeSupportTokenGridCenter(this);
+	else
+		entityCenter = this.center;
+	ruler.rulerOffset = {x: entityCenter.x - event.data.origin.x, y: entityCenter.y - event.data.origin.y};
+	if (game.settings.get(settingsKey, "autoStartMeasurement")) {
+		let options = {};
+		setSnapParameterOnOptions(ruler, options);
+		ruler.dragRulerStart(options, false);
+	}
+}
+
+function onEntityLeftDragMoveSnap(wrapped, event) {
+	applyGridlessSnapping.call(this, event);
+	onEntityLeftDragMove.call(this, wrapped, event);
+}
+
+function onEntityLeftDragMove(wrapped, event) {
+	wrapped(event);
+	const ruler = canvas.controls.ruler
+	if (ruler.isDragRuler)
+		onMouseMove.call(ruler, event)
+}
+
+function onEntityDragLeftDrop(event) {
+	const ruler = canvas.controls.ruler
+	if (!ruler.isDragRuler) {
+		ruler.draggedEntity = undefined;
+		return false
+	}
+	// When we're dragging a measured template no token will ever be selected,
+	// resulting in only the dragged template to be moved as would be expected
+	const selectedTokens = canvas.tokens.controlled
+	// This can happen if the user presses ESC during drag (maybe there are other ways too)
+	if (selectedTokens.length === 0)
+		selectedTokens.push(ruler.draggedEntity);
+	// This can happen if the ruler is being dragged so rapidly that the drag move handler hasn't been called before dropping
+	if (ruler._state === Ruler.STATES.STARTING)
+		onMouseMove.call(ruler, event);
+	ruler._state = Ruler.STATES.MOVING
+	moveEntities.call(ruler, ruler.draggedEntity, selectedTokens);
+	return true
+}
+
+function onEntityDragLeftCancel(event) {
+	// This function is invoked by right clicking
+	const ruler = canvas.controls.ruler
+	if (!ruler.draggedEntity || ruler._state === Ruler.STATES.MOVING)
+		return false
+
+	const rightClickAction = game.settings.get(settingsKey, "rightClickAction");
+	let options = {};
+	setSnapParameterOnOptions(ruler, options);
+
+	if (ruler._state === Ruler.STATES.INACTIVE) {
+		if (rightClickAction !== RightClickAction.CREATE_WAYPOINT)
+			return false;
+		ruler.dragRulerStart(options);
+		event.preventDefault();
+	}
+	else if (ruler._state === Ruler.STATES.MEASURING) {
+		switch (rightClickAction) {
+			case RightClickAction.CREATE_WAYPOINT:
+				event.preventDefault();
+				ruler.dragRulerAddWaypoint(ruler.destination, options);
+				break;
+			case RightClickAction.DELETE_WAYPOINT:
+				ruler.dragRulerDeleteWaypoint(event, options);
+				break;
+			case RightClickAction.ABORT_DRAG:
+				ruler.dragRulerAbortDrag();
+				break;
+		}
+	}
+	return true;
+}
+
+function applyGridlessSnapping(event) {
+	const ruler = canvas.controls.ruler;
+	if (!game.settings.get(settingsKey, "useGridlessRaster"))
+		return;
+	if (!ruler.isDragRuler)
+		return;
+	if (disableSnap)
+		return;
+	if (canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS)
+		return;
+
+	const rasterWidth = 35 / canvas.stage.scale.x;
+	const tokenX = event.data.destination.x;
+	const tokenY = event.data.destination.y;
+	const destination = {x: tokenX + ruler.rulerOffset.x, y: tokenY + ruler.rulerOffset.y};
+	const ranges = getRangesFromSpeedProvider(ruler.draggedEntity);
+
+	const terrainRulerAvailable = game.modules.get("terrain-ruler")?.active;
+	if (terrainRulerAvailable) {
+		const segments = Ruler.dragRulerGetRaysFromWaypoints(ruler.waypoints, destination).map(ray => {return {ray}});
+		const pinpointDistances = new Map();
+		for (const range of ranges) {
+			pinpointDistances.set(range.range, null);
+		}
+		terrainRuler.measureDistances(segments, {pinpointDistances});
+		const targetDistance = Array.from(pinpointDistances.entries())
+			.filter(([_key, val]) => val)
+			.reduce((value, current) => value[0] > current[0] ? value : current, [0, null]);
+		const rasterLocation = targetDistance[1];
+		if (rasterLocation) {
+			const deltaX = destination.x - rasterLocation.x;
+			const deltaY = destination.y - rasterLocation.y;
+			const rasterDistance = Math.hypot(deltaX, deltaY);
+			if (rasterDistance < rasterWidth) {
+				event.data.destination.x = rasterLocation.x - ruler.rulerOffset.x;
+				event.data.destination.y = rasterLocation.y - ruler.rulerOffset.y;
+			}
+		}
+	}
+	else {
+		let waypointDistance = 0;
+		let origin = event.data.origin;
+		if (ruler.waypoints.length > 1) {
+			const segments = Ruler.dragRulerGetRaysFromWaypoints(ruler.waypoints, destination).map(ray => {return {ray}});
+			origin = segments.pop().ray.A;
+			waypointDistance = canvas.grid.measureDistances(segments).reduce((a, b) => a + b);
+			origin = {x: origin.x - ruler.rulerOffset.x, y: origin.y - ruler.rulerOffset.y};
+		}
+
+		const deltaX = tokenX - origin.x;
+		const deltaY = tokenY - origin.y;
+		const distance = Math.hypot(deltaX, deltaY);
+		// targetRange will be the largest range that's still smaller than distance
+		let targetDistance = ranges
+			.map(range => range.range)
+			.map(range => range - waypointDistance)
+			.map(range => range * canvas.dimensions.size / canvas.dimensions.distance)
+			.filter(range => range < distance)
+			.reduce((a, b) => Math.max(a, b), 0);
+		if (targetDistance) {
+			if (distance < targetDistance + rasterWidth) {
+				event.data.destination.x = origin.x + deltaX * targetDistance / distance;
+				event.data.destination.y = origin.y + deltaY * targetDistance / distance;
+			}
+		}
+	}
+}

js/migration.js

@@ -0,0 +1,43 @@
+import {RightClickAction, settingsKey} from "./settings.js"
+
+const currentDataVersion = "1.10.0"
+
+export async function performMigrations() {
+	if (game.user.isGM)
+		await performWorldMigraionts()
+	await performClientMigrations()
+}
+
+async function performWorldMigraionts() {
+	let dataVersion = game.settings.get(settingsKey, "dataVersion");
+
+	if (dataVersion === currentDataVersion)
+		return;
+
+	if (dataVersion === "fresh install") {
+		game.settings.set(settingsKey, "dataVersion", currentDataVersion)
+		return
+	}
+
+	if (dataVersion === "1.3.0") {
+		dataVersion = "1.10.0"
+	}
+
+	game.settings.set(settingsKey, "dataVersion", dataVersion);
+}
+
+async function performClientMigrations() {
+	let dataVersion = game.settings.get(settingsKey, "clientDataVersion");
+
+	if (dataVersion === "fresh install") {
+		// Start of migration from unnamed version (< 1.10.0). TODO Remove in a future version
+		const swapSpacebarRightClick = game.settings.storage.get("client").getItem(`${settingsKey}.swapSpacebarRightClick`);
+		if (swapSpacebarRightClick) {
+			game.settings.set(settingsKey, "rightClickAction", RightClickAction.CREATE_WAYPOINT);
+			await game.keybindings.set(settingsKey, "createWaypoint", []);
+			await game.keybindings.set(settingsKey, "deleteWaypoint", [{key: "Space"}]);
+		}
+		// End of migration from unnamed version
+		game.settings.set(settingsKey, "clientDataVersion", currentDataVersion)
+	}
+}

js/movement_tracking.js

@@ -0,0 +1,108 @@
+import {measureDistances} from "./compatibility.js";
+import {recalculate, updateCombatantDragRulerFlags} from "./socket.js";
+import {getTokenShape, isClose, zip} from "./util.js";
+
+function initTrackingFlag(combatant) {
+	const initialFlag = {passedWaypoints: [], trackedRound: 0};
+	let dragRulerFlag = combatant.data.flags.dragRuler;
+	if (dragRulerFlag) {
+		if (isNaN(dragRulerFlag.trackedRound)) {
+			mergeObject(dragRulerFlag, initialFlag);
+		}
+	}
+	else {
+		combatant.data.flags.dragRuler = initialFlag;
+	}
+}
+
+function getInitializedCombatant(token, combat) {
+	const combatant = combat.getCombatantByToken(token.id);
+	if (!combatant)
+		return undefined;
+	initTrackingFlag(combatant);
+	return combatant;
+}
+
+export async function trackRays(tokens, tokenRays) {
+	const combat = game.combat;
+	if (!combat)
+		return;
+	if (!combat.started)
+		return;
+	if (!(tokens instanceof Array)) {
+		tokens = [tokens];
+		tokenRays = [tokenRays];
+	}
+	const updates = Array.from(zip(tokens, tokenRays)).map(([token, rays]) => calculateUpdate(combat, token, rays)).filter(Boolean);
+	await updateCombatantDragRulerFlags(combat, updates);
+}
+
+function calculateUpdate(combat, token, rays) {
+	const combatant = getInitializedCombatant(token, combat);
+	if (!combatant)
+		return;
+
+	// Check if we have entered a new round. If so, remove the currently stored path
+	if (combat.data.round > combatant.data.flags.dragRuler.trackedRound) {
+		combatant.data.flags.dragRuler.passedWaypoints = [];
+		combatant.data.flags.dragRuler.trackedRound = combat.data.round;
+	}
+
+	// Add the passed waypoints to the combatant
+	const terrainRulerAvailable = game.modules.get("terrain-ruler")?.active;
+	const dragRulerFlags = combatant.data.flags.dragRuler;
+	const waypoints = dragRulerFlags.passedWaypoints;
+	for (const ray of rays) {
+		// Ignore rays that have the same start and end coordinates
+		if (ray.A.x !== ray.B.x || ray.A.y !== ray.B.y) {
+			if (terrainRulerAvailable) {
+				measureDistances([{ray}], token, getTokenShape(token), {terrainRulerInitialState: waypoints[waypoints.length - 1]?.dragRulerFinalState, enableTerrainRuler: terrainRulerAvailable});
+				ray.A.dragRulerVisitedSpaces = ray.terrainRulerVisitedSpaces;
+				ray.A.dragRulerFinalState = ray.terrainRulerFinalState;
+			}
+			waypoints.push(ray.A);
+		}
+	}
+	return {_id: combatant.id, dragRulerFlags};
+}
+
+export function getMovementHistory(token) {
+	const combat = game.combat;
+	if (!combat)
+		return [];
+	const combatant = combat.getCombatantByToken(token.id);
+	if (!combatant)
+		return [];
+	const dragRulerFlags = combatant.data.flags.dragRuler;
+	if (!dragRulerFlags)
+		return [];
+	if (combat.data.round > dragRulerFlags.trackedRound)
+		return [];
+	return dragRulerFlags.passedWaypoints ?? [];
+}
+
+export async function removeLastHistoryEntryIfAt(token, x, y) {
+	const history = getMovementHistory(token);
+	if (history.length === 0)
+		return;
+	const entry = history[history.length - 1];
+	if (!isClose(x + token.w / 2, entry.x, 0.1) || !isClose(y + token.h / 2, entry.y, 0.1)) {
+		return;
+	}
+	history.pop();
+	const combat = game.combat;
+	const combatant = combat.getCombatantByToken(token.id);
+	await updateCombatantDragRulerFlags(combat, [{_id: combatant.id, dragRulerFlags: combatant.data.flags.dragRuler}]);
+}
+
+export async function resetMovementHistory(combat, combatantId) {
+	const combatant = combat.combatants.get(combatantId);
+	const dragRulerFlags = combatant.data.flags.dragRuler;
+	if (!dragRulerFlags)
+		return;
+	dragRulerFlags.passedWaypoints = null;
+	dragRulerFlags.trackedRound = null;
+	dragRulerFlags.rulerState = null;
+	await updateCombatantDragRulerFlags(combat, [{_id: combatantId, dragRulerFlags}]);
+	recalculate();
+}

js/pathfinding.js

@@ -0,0 +1,187 @@
+import {getGridPositionFromPixelsObj, getPixelsFromGridPositionObj} from "./foundry_fixes.js";
+import {togglePathfinding} from "./keybindings.js";
+import {debugGraphics} from "./main.js";
+import {settingsKey} from "./settings.js";
+import {getSnapPointForTokenObj, iterPairs} from "./util.js";
+
+import * as GridlessPathfinding from "../wasm/gridless_pathfinding.js"
+
+let cachedNodes = undefined;
+let use5105 = false;
+let gridlessPathfinders = new Map();
+
+export function isPathfindingEnabled() {
+	if (this.user !== game.user)
+		return false;
+	if (!game.user.isGM && !game.settings.get(settingsKey, "allowPathfinding"))
+		return false;
+	return game.settings.get(settingsKey, "autoPathfinding") != togglePathfinding;
+}
+
+export function findPath(from, to, token, previousWaypoints) {
+	if (canvas.grid.type === CONST.GRID_TYPES.GRIDLESS) {
+		let tokenSize = Math.max(token.data.width, token.data.height) * canvas.dimensions.size;
+		let pathfinder = gridlessPathfinders.get(tokenSize);
+		if (!pathfinder) {
+			pathfinder = GridlessPathfinding.initialize(canvas.walls.placeables, tokenSize);
+			gridlessPathfinders.set(tokenSize, pathfinder);
+		}
+		paintGridlessPathfindingDebug(pathfinder);
+		return GridlessPathfinding.findPath(pathfinder, from, to);
+	}
+	else {
+		const lastNode = calculatePath(from, to, token, previousWaypoints);
+		if (!lastNode)
+			return null;
+		paintGriddedPathfindingDebug(lastNode, token);
+		const path = [];
+		let currentNode = lastNode;
+		while (currentNode) {
+			// TODO Check if the distance doesn't change
+			if (path.length >= 2 && !stepCollidesWithWall(currentNode.node, path[path.length - 2], token))
+				// Replace last waypoint if the current waypoint leads to a valid path
+				path[path.length - 1] = {x: currentNode.node.x, y: currentNode.node.y};
+			else
+				path.push({x: currentNode.node.x, y: currentNode.node.y});
+			currentNode = currentNode.previous;
+		}
+		return path;
+	}
+}
+
+export function wipePathfindingCache() {
+	cachedNodes = undefined;
+	for (const pathfinder of gridlessPathfinders.values()) {
+		GridlessPathfinding.free(pathfinder);
+	}
+	gridlessPathfinders.clear();
+	if (debugGraphics)
+		debugGraphics.removeChildren().forEach(c => c.destroy());
+}
+
+function getNode(pos, token, initialize=true) {
+	pos = {layer: 0, ...pos}; // Copy pos and set pos.layer to the default value if it's unset
+	if (!cachedNodes)
+		cachedNodes = new Array(2);
+	if (!cachedNodes[pos.layer])
+		cachedNodes[pos.layer] = new Array(Math.ceil(canvas.dimensions.height / canvas.grid.h));
+	if (!cachedNodes[pos.layer][pos.y])
+		cachedNodes[pos.layer][pos.y] = new Array(Math.ceil(canvas.dimensions.width / canvas.grid.w));
+	if (!cachedNodes[pos.layer][pos.y][pos.x]) {
+		cachedNodes[pos.layer][pos.y][pos.x] = pos;
+	}
+
+	const node = cachedNodes[pos.layer][pos.y][pos.x];
+	if (initialize && !node.edges) {
+		node.edges = [];
+		for (const neighborPos of canvas.grid.grid.getNeighbors(pos.y, pos.x).map(([y, x]) => {return {x, y};})) {
+			if (neighborPos.x < 0 || neighborPos.y < 0)
+				continue;
+			// TODO Work with pixels instead of grid locations
+			if (!stepCollidesWithWall(pos, neighborPos, token)) {
+				const isDiagonal = node.x !== neighborPos.x && node.y !== neighborPos.y && canvas.grid.type === CONST.GRID_TYPES.SQUARE;
+				let targetLayer = pos.layer;
+				if (use5105 && isDiagonal)
+					targetLayer = 1 - targetLayer;
+				const neighbor = getNode({...neighborPos, layer: targetLayer}, token, false);
+
+				// TODO We currently assume a cost of one or two for all transitions. Change this for difficult terrain support
+				let edgeCost = 1;
+				if (isDiagonal) {
+					// We charge 0.0001 more for edges to avoid unnecessary diagonal steps
+					edgeCost = pos.layer === 1 && targetLayer === 0 ? 2 : 1.0001;
+				}
+				node.edges.push({target: neighbor, cost: edgeCost});
+			}
+		}
+	}
+	return node;
+}
+
+function calculatePath(from, to, token, previousWaypoints) {
+	if (game.system.id === "pf2e")
+		use5105 = true;
+	if (canvas.grid.diagonalRule === "5105")
+		use5105 = true;
+	let startLayer = 0;
+	if (use5105 && canvas.grid.type === CONST.GRID_TYPES.SQUARE) {
+		previousWaypoints = previousWaypoints.map(w => getGridPositionFromPixelsObj(w));
+		startLayer = calcNoDiagonals(previousWaypoints) % 2;
+	}
+	const nextNodes = [{node: getNode({...to, layer: startLayer}, token), cost: 0, estimated: estimateCost(to, from), previous: null}];
+	const previousNodes = new Set();
+	while (nextNodes.length > 0) {
+		// Sort by estimated cost, high to low
+		// TODO Re-sorting every iteration is expensive. Think of something better
+		nextNodes.sort((a, b) => b.estimated - a.estimated);
+		// Get node with cheapest estimate
+		const currentNode = nextNodes.pop();
+		if (currentNode.node.x === from.x && currentNode.node.y === from.y)
+			return currentNode;
+		previousNodes.add(currentNode.node);
+		for (const edge of currentNode.node.edges) {
+			const neighborNode = getNode(edge.target, token);
+			if (previousNodes.has(neighborNode))
+				continue;
+			const neighbor = {node: neighborNode, cost: currentNode.cost + edge.cost, estimated: currentNode.cost + edge.cost + estimateCost(neighborNode, from), previous: currentNode};
+			const neighborIndex = nextNodes.findIndex(node => node.node === neighbor.node);
+			if (neighborIndex >= 0) {
+				// If the neighbor is cheaper to reach via the current route than through previously discovered routes, replace it
+				if (nextNodes[neighborIndex].cost > neighbor.cost) {
+					nextNodes[neighborIndex] = neighbor;
+				}
+			}
+			else {
+				nextNodes.push(neighbor);
+			}
+		}
+	}
+}
+
+function calcNoDiagonals(waypoints) {
+	let diagonals = 0;
+	for (const [p1, p2] of iterPairs(waypoints)) {
+		diagonals += Math.min(Math.abs(p1.x - p2.x), Math.abs(p1.y - p2.y));
+	}
+	return diagonals;
+}
+
+function estimateCost(pos, target) {
+	return Math.max(Math.abs(pos.x - target.x), Math.abs(pos.y - target.y));
+}
+
+function stepCollidesWithWall(from, to, token) {
+	const stepStart = getSnapPointForTokenObj(getPixelsFromGridPositionObj(from), token);
+	const stepEnd = getSnapPointForTokenObj(getPixelsFromGridPositionObj(to), token);
+	return canvas.walls.checkCollision(new Ray(stepStart, stepEnd));
+}
+
+function paintGriddedPathfindingDebug(lastNode, token) {
+	if (!CONFIG.debug.dragRuler)
+		return;
+
+	debugGraphics.removeChildren().forEach(c => c.destroy());
+	let currentNode = lastNode;
+	while (currentNode) {
+		let text = new PIXI.Text(currentNode.cost.toFixed(0));
+		let pixels = getSnapPointForTokenObj(getPixelsFromGridPositionObj(currentNode.node), token);
+		text.anchor.set(0.5, 1.0);
+		text.x = pixels.x;
+		text.y = pixels.y;
+		debugGraphics.addChild(text);
+		currentNode = currentNode.previous;
+	}
+}
+
+function paintGridlessPathfindingDebug(pathfinder) {
+	if (!CONFIG.debug.dragRuler)
+		return;
+
+	debugGraphics.removeChildren().forEach(c => c.destroy());
+	let graphic = new PIXI.Graphics();
+	graphic.lineStyle(2, 0x440000);
+	for (const point of GridlessPathfinding.debugGetPathfindingPoints(pathfinder)) {
+		graphic.drawCircle(point.x, point.y, 5);
+	}
+	debugGraphics.addChild(graphic);
+}

js/ruler.js

@@ -0,0 +1,212 @@
+import {currentSpeedProvider, getColorForDistanceAndToken, getRangesFromSpeedProvider} from "./api.js";
+import {getHexSizeSupportTokenGridCenter} from "./compatibility.js";
+import {cancelScheduledMeasurement, measure} from "./foundry_imports.js"
+import {getMovementHistory} from "./movement_tracking.js";
+import {settingsKey} from "./settings.js";
+import {getSnapPointForEntity} from "./util.js";
+
+export function extendRuler() {
+	class DragRulerRuler extends Ruler {
+		// Functions below are overridden versions of functions in Ruler
+		constructor(user, {color=null}={}) {
+			super(user, {color});
+			this.previousWaypoints = [];
+			this.previousLabels = this.addChild(new PIXI.Container());
+		}
+
+		clear() {
+			super.clear();
+			this.previousWaypoints = [];
+			this.previousLabels.removeChildren().forEach(c => c.destroy());
+			this.dragRulerRanges = undefined;
+			cancelScheduledMeasurement.call(this);
+		}
+
+		async moveToken(event) {
+			// Disable moveToken if Drag Ruler is active
+			if (!this.isDragRuler)
+				return await super.moveToken(event);
+		}
+
+		toJSON() {
+			const json = super.toJSON();
+			if (this.draggedEntity) {
+				const isToken = this.draggedEntity instanceof Token;
+				json.draggedEntityIsToken = isToken;
+				json.draggedEntity = this.draggedEntity.id;
+				json.waypoints = json.waypoints.map(old => {
+					let w = duplicate(old);
+					w.isPathfinding = undefined;
+					return w;
+				});
+			}
+			return json;
+		}
+
+		update(data) {
+			// Don't show a GMs drag ruler to non GM players
+			if (data.draggedEntity && this.user.isGM && !game.user.isGM && !game.settings.get(settingsKey, "showGMRulerToPlayers"))
+				return;
+
+			if (data.draggedEntity) {
+				if (data.draggedEntityIsToken)
+					this.draggedEntity = canvas.tokens.get(data.draggedEntity);
+				else
+					this.draggedEntity = canvas.templates.get(data.draggedEntity);
+			}
+
+			super.update(data);
+		}
+
+		measure(destination, options={}) {
+			if (this.isDragRuler) {
+				// If this is the ruler of a remote user take the waypoints as they were transmitted and don't apply any additional snapping to them
+				if (this.user !== game.user)
+					options.snap = false;
+				return measure.call(this, destination, options);
+			}
+			else {
+				return super.measure(destination, options);
+			}
+		}
+
+		_endMeasurement() {
+			super._endMeasurement();
+			this.draggedEntity = null;
+		}
+
+		// The functions below aren't present in the orignal Ruler class and are added by Drag Ruler
+		dragRulerAddWaypoint(point, options={}) {
+			options.snap = options.snap ?? true;
+			if (options.snap) {
+				point = getSnapPointForEntity(point.x, point.y, this.draggedEntity);
+			}
+			this.waypoints.push(new PIXI.Point(point.x, point.y));
+			this.labels.addChild(new PreciseText("", CONFIG.canvasTextStyle));
+			this.waypoints.filter(waypoint => waypoint.isPathfinding).forEach(waypoint => waypoint.isPathfinding = false);
+		}
+
+		dragRulerAddWaypointHistory(waypoints) {
+			waypoints.forEach(waypoint => waypoint.isPrevious = true);
+			this.waypoints = this.waypoints.concat(waypoints);
+			for (const waypoint of waypoints) {
+				this.labels.addChild(new PreciseText("", CONFIG.canvasTextStyle));
+			}
+		}
+
+		dragRulerClearWaypoints() {
+			this.waypoints = [];
+			this.labels.removeChildren().forEach(c => c.destroy());
+		}
+
+		dragRulerDeleteWaypoint(event={preventDefault: () => {return}}, options={}) {
+			this.dragRulerRemovePathfindingWaypoints();
+			options.snap = options.snap ?? true;
+			if (this.waypoints.filter(w => !w.isPrevious).length > 1) {
+				event.preventDefault();
+				const mousePosition = canvas.app.renderer.plugins.interaction.mouse.getLocalPosition(canvas.tokens);
+				const rulerOffset = this.rulerOffset;
+
+				// Options are not passed to _removeWaypoint in vanilla Foundry.
+				// Send them in case other modules have overriden that behavior and accept an options parameter (Toggle Snap to Grid)
+				this._removeWaypoint({x: mousePosition.x + rulerOffset.x, y: mousePosition.y + rulerOffset.y}, options);
+				game.user.broadcastActivity({ruler: this});
+			}
+			else {
+				this.dragRulerAbortDrag(event);
+			}
+		}
+
+		dragRulerRemovePathfindingWaypoints() {
+			this.waypoints.filter(waypoint => waypoint.isPathfinding).forEach(_ => this.labels.removeChild(this.labels.children[this.labels.children.length - 1]).destroy());
+			this.waypoints = this.waypoints.filter(waypoint => !waypoint.isPathfinding);
+		}
+
+		dragRulerAbortDrag(event={preventDefault: () => {return}}) {
+			const token = this.draggedEntity;
+			this._endMeasurement();
+
+			// Deactivate the drag workflow in mouse
+			token.mouseInteractionManager._deactivateDragEvents();
+			token.mouseInteractionManager.state = token.mouseInteractionManager.states.HOVER;
+
+			// This will cancel the current drag operation
+			// Pass in a fake event that hopefully is enough to allow other modules to function
+			token._onDragLeftCancel(event);
+		}
+
+		async dragRulerRecalculate(tokenIds) {
+			if (this._state !== Ruler.STATES.MEASURING)
+				return;
+			if (tokenIds && !tokenIds.includes(this.draggedEntity.id))
+				return;
+			const waypoints = this.waypoints.filter(waypoint => !waypoint.isPrevious);
+			this.dragRulerClearWaypoints();
+			if (game.settings.get(settingsKey, "enableMovementHistory"))
+				this.dragRulerAddWaypointHistory(getMovementHistory(this.draggedEntity));
+			for (const waypoint of waypoints) {
+				this.dragRulerAddWaypoint(waypoint, {snap: false});
+			}
+			this.measure(this.destination);
+			game.user.broadcastActivity({ruler: this});
+		}
+
+		static dragRulerGetRaysFromWaypoints(waypoints, destination) {
+			if ( destination )
+				waypoints = waypoints.concat([destination]);
+			return waypoints.slice(1).map((wp, i) => {
+				const ray =  new Ray(waypoints[i], wp);
+				ray.isPrevious = Boolean(waypoints[i].isPrevious);
+				return ray;
+			});
+		}
+
+		dragRulerGetColorForDistance(distance) {
+			if (!this.isDragRuler)
+				return this.color;
+			if (!this.draggedEntity.actor) {
+				return this.color;
+			}
+			// Don't apply colors if the current user doesn't have at least observer permissions
+			if (this.draggedEntity.actor.permission < 2) {
+				// If this is a pc and alwaysShowSpeedForPCs is enabled we show the color anyway
+				if (!(this.draggedEntity.actor.data.type === "character" && game.settings.get(settingsKey, "alwaysShowSpeedForPCs")))
+					return this.color;
+			}
+			distance = Math.round(distance * 100) / 100;
+			if (!this.dragRulerRanges)
+				this.dragRulerRanges = getRangesFromSpeedProvider(this.draggedEntity);
+			return getColorForDistanceAndToken(distance, this.draggedEntity, this.dragRulerRanges) ?? this.color;
+		}
+
+		dragRulerStart(options, measureImmediately=true) {
+			const entity = this.draggedEntity;
+			const isToken = entity instanceof Token;
+			if (isToken && !currentSpeedProvider.usesRuler(entity))
+				return;
+			const ruler = canvas.controls.ruler;
+			ruler.clear();
+			ruler._state = Ruler.STATES.STARTING;
+			let entityCenter;
+			if (isToken && canvas.grid.isHex && game.modules.get("hex-size-support")?.active && CONFIG.hexSizeSupport.getAltSnappingFlag(entity))
+				entityCenter = getHexSizeSupportTokenGridCenter(entity);
+			else
+				entityCenter = entity.center;
+			if (isToken && game.settings.get(settingsKey, "enableMovementHistory"))
+				ruler.dragRulerAddWaypointHistory(getMovementHistory(entity));
+			ruler.dragRulerAddWaypoint(entityCenter, {snap: false});
+			const mousePosition = canvas.app.renderer.plugins.interaction.mouse.getLocalPosition(canvas.tokens);
+			const destination = {x: mousePosition.x + ruler.rulerOffset.x, y: mousePosition.y + ruler.rulerOffset.y};
+			if (measureImmediately)
+				ruler.measure(destination, options);
+		}
+
+		dragRulerSendState() {
+			game.user.broadcastActivity({
+				ruler: this.toJSON()
+			});
+		}
+	}
+
+	Ruler = DragRulerRuler;
+}

js/settings.js

@@ -0,0 +1,305 @@
+import {availableSpeedProviders, currentSpeedProvider, getDefaultSpeedProvider, updateSpeedProvider} from "./api.js";
+import {SpeedProvider} from "./speed_provider.js"
+import { early_isGM } from "./util.js";
+
+export const settingsKey = "drag-ruler";
+
+export const RightClickAction = Object.freeze({
+	CREATE_WAYPOINT: 0,
+	DELETE_WAYPOINT: 1,
+	ABORT_DRAG:2,
+});
+
+export function registerSettings() {
+	game.settings.register(settingsKey, "dataVersion", {
+		scope: "world",
+		config: false,
+		type: String,
+		default: "fresh install"
+	})
+
+	game.settings.register(settingsKey, "clientDataVersion", {
+		scope: "client",
+		config: false,
+		type: String,
+		default: "fresh install"
+	});
+
+	game.settings.register(settingsKey, "rightClickAction", {
+		name: "drag-ruler.settings.rightClickAction.name",
+		hint: "drag-ruler.settings.rightClickAction.hint",
+		config: true,
+		type: Number,
+		default: RightClickAction.DELETE_WAYPOINT,
+		choices: {
+			0: "drag-ruler.settings.rightClickAction.choices.create",
+			1: "drag-ruler.settings.rightClickAction.choices.delete",
+			2: "drag-ruler.settings.rightClickAction.choices.cancel",
+		},
+	});
+
+	game.settings.register(settingsKey, "autoStartMeasurement", {
+		name: "drag-ruler.settings.autoStartMeasurement.name",
+		hint: "drag-ruler.settings.autoStartMeasurement.hint",
+		scope: "client",
+		config: true,
+		type: Boolean,
+		default: true,
+	});
+
+	game.settings.register(settingsKey, "useGridlessRaster", {
+		name: "drag-ruler.settings.useGridlessRaster.name",
+		hint: "drag-ruler.settings.useGridlessRaster.hint",
+		scope: "client",
+		config: true,
+		type: Boolean,
+		default: true,
+	});
+
+	game.settings.register(settingsKey, "alwaysShowSpeedForPCs", {
+		name: "drag-ruler.settings.alwaysShowSpeedForPCs.name",
+		hint: "drag-ruler.settings.alwaysShowSpeedForPCs.hint",
+		scope: "world",
+		config: true,
+		type: Boolean,
+		default: true,
+	})
+
+	game.settings.register(settingsKey, "showGMRulerToPlayers", {
+		name: "drag-ruler.settings.showGMRulerToPlayers.name",
+		hint: "drag-ruler.settings.showGMRulerToPlayers.hint",
+		scope: "world",
+		config: true,
+		type: Boolean,
+		default: true,
+	})
+
+	game.settings.register(settingsKey, "enableMovementHistory", {
+		name: "drag-ruler.settings.enableMovementHistory.name",
+		hint: "drag-ruler.settings.enableMovementHistory.hint",
+		scope: "world",
+		config: true,
+		type: Boolean,
+		default: true,
+	});
+
+	game.settings.register(settingsKey, "allowPathfinding", {
+		name: "drag-ruler.settings.allowPathfinding.name",
+		hint: "drag-ruler.settings.allowPathfinding.hint",
+		scope: "world",
+		config: true,
+		type: Boolean,
+		default: false,
+		onChange: () => location.reload(),
+	});
+
+	game.settings.register(settingsKey, "autoPathfinding", {
+		name: "drag-ruler.settings.autoPathfinding.name",
+		hint: "drag-ruler.settings.autoPathfinding.hint",
+		scpoe: "client",
+		config: early_isGM() || game.settings.get(settingsKey, "allowPathfinding"),
+		type: Boolean,
+		defualt: false,
+	});
+
+	game.settings.register(settingsKey, "lastTerrainRulerHintTime", {
+		config: false,
+		type: Number,
+		default: 0,
+	});
+
+	game.settings.register(settingsKey, "neverShowTerrainRulerHint", {
+		config: false,
+		type: Boolean,
+		default: false,
+	});
+
+	// This setting will be modified by the api if modules register to it
+	game.settings.register(settingsKey, "speedProvider", {
+		scope: "world",
+		config: false,
+		type: String,
+		default: getDefaultSpeedProvider(),
+		onChange: updateSpeedProvider,
+	})
+
+	game.settings.registerMenu(settingsKey, "speedProviderSettings", {
+		name: "drag-ruler.settings.speedProviderSettings.name",
+		hint: "drag-ruler.settings.speedProviderSettings.hint",
+		label: "drag-ruler.settings.speedProviderSettings.button",
+		icon: "fas fa-tachometer-alt",
+		type: SpeedProviderSettings,
+		restricted: false,
+	})
+}
+
+class SpeedProviderSettings extends FormApplication {
+	static get defaultOptions() {
+		return mergeObject(super.defaultOptions, {
+			id: "drag-ruler-speed-provider-settings",
+			title: game.i18n.localize("drag-ruler.settings.speedProviderSettings.windowTitle"),
+			template: "modules/drag-ruler/templates/speed_provider_settings.html",
+			width: 600,
+		})
+	}
+
+	getData(options={}) {
+		const data = {}
+		data.isGM = game.user.isGM
+		const selectedProvider = currentSpeedProvider.id
+
+		// Insert all speed providers into the template data
+		data.providers = Object.values(availableSpeedProviders).map(speedProvider => {
+			const provider = {}
+			provider.id = speedProvider.id
+			provider.hasSettings = speedProvider instanceof SpeedProvider
+			if (provider.hasSettings)
+				provider.settings = enumerateProviderSettings(speedProvider)
+			let dotPosition = provider.id.indexOf(".")
+			if (dotPosition === -1)
+				dotPosition = provider.id.length
+			const type = provider.id.substring(0, dotPosition)
+			const id = provider.id.substring(dotPosition + 1)
+			if (type === "native") {
+				provider.selectTitle = game.i18n.localize("drag-ruler.settings.speedProviderSettings.speedProvider.choices.native")
+			}
+			else {
+				let name
+				if (type === "module") {
+					name = game.modules.get(id).data.title
+				}
+				else {
+					name = game.system.data.title
+				}
+				provider.selectTitle = game.i18n.format(`drag-ruler.settings.speedProviderSettings.speedProvider.choices.${type}`, {name})
+			}
+			provider.isSelected = provider.id === selectedProvider
+			return provider
+		})
+		data.selectedProviderName = data.providers.find(provider => provider.isSelected).selectTitle
+
+		data.providerSelection = {
+			id: "speedProvider",
+			name: game.i18n.localize("drag-ruler.settings.speedProviderSettings.speedProvider.name"),
+			hint: game.i18n.localize("drag-ruler.settings.speedProviderSettings.speedProvider.hint"),
+			type: String,
+			choices: data.providers.reduce((choices, provider) => {
+				choices[provider.id] = provider.selectTitle
+				return choices
+			}, {}),
+			value: selectedProvider,
+			isCheckbox: false,
+			isSelect: true,
+			isRange: false,
+		}
+		return data
+	}
+
+	async _updateObject(event, formData) {
+		const selectedSpeedProvider = game.user.isGM ? formData.speedProvider : game.settings.get(settingsKey, "speedProvider")
+		for (let [key, value] of Object.entries(formData)) {
+			// Check if this is color, convert the value to an integer
+			const splitKey = key.split(".", 3)
+			if (splitKey[0] !== "native")
+				splitKey.shift()
+			if (splitKey.length >= 2 && splitKey[1] == "color") {
+				value = parseInt(value.substring(1), 16)
+			}
+
+			// Don't change settings for speed providers that aren't currently active
+			if (key !== "speedProvider" && !key.startsWith(selectedSpeedProvider))
+				continue
+
+			// Get the key for the current setting
+			let setting
+			if (key === "speedProvider")
+				setting = "speedProvider"
+			else
+				setting = `speedProviders.${key}`
+
+			// Get the old setting value
+			const oldValue = game.settings.get(settingsKey, setting)
+
+			// Only update the setting if it has been changed (this leaves the default in place if it hasn't been touched)
+			if (value !== oldValue)
+				game.settings.set(settingsKey, setting, value)
+		}
+
+		// Activate the configured speed provider
+		updateSpeedProvider()
+	}
+
+	activateListeners(html) {
+		super.activateListeners(html)
+		html.find("select[name=speedProvider]").change(this.onSpeedProviderChange.bind(this))
+	}
+
+	onSpeedProviderChange(event) {
+		// Hide all module settings
+		document.querySelectorAll(".drag-ruler-provider-settings").forEach(element => element.style.display = "none")
+		// Show the settings block for the currently selected module
+		document.getElementById(`drag-ruler.provider.${event.currentTarget.value}`).style.display = ""
+
+		// Recalculate window height
+		this.element[0].style.height = null
+		this.position.height = undefined
+	}
+}
+
+function toDomHex(value) {
+	const hex = value.toString(16)
+	return "#" + "0".repeat(Math.max(0, 6 - hex.length)) + hex
+}
+
+function enumerateProviderSettings(provider) {
+	const colorSettings = []
+	const unreachableColor = {id: "unreachable", name: "drag-ruler.settings.speedProviderSettings.color.unreachable.name"}
+
+	// Resolve settings for the colors
+	for (const color of provider.colors.concat([unreachableColor])) {
+		// Localize the name, if avaliable. If no name is available use the id as name
+		const colorName = color.name ? game.i18n.localize(color.name) : color.id
+		let hint
+		if (color === unreachableColor)
+			hint = game.i18n.localize("drag-ruler.settings.speedProviderSettings.color.unreachable.hint")
+		else
+			hint = game.i18n.format("drag-ruler.settings.speedProviderSettings.color.hint", {colorName})
+		colorSettings.push({
+			id: `${provider.id}.color.${color.id}`,
+			name: game.i18n.format("drag-ruler.settings.speedProviderSettings.color.name", {colorName}),
+			hint: hint,
+			type: Number,
+			value: toDomHex(game.settings.get(settingsKey, `speedProviders.${provider.id}.color.${color.id}`)),
+			isCheckbox: false,
+			isSelect: false,
+			isRange: false,
+			isColor: true,
+		})
+	}
+
+	// Prepare regular settings
+	const settings = []
+	for (const setting of provider.settings) {
+		try {
+			if (setting.scope === "world" && !game.user.isGM)
+				continue
+			const s = duplicate(setting)
+			s.id = `${provider.id}.setting.${s.id}`
+			s.name = game.i18n.localize(s.name)
+			s.hint = game.i18n.localize(s.hint)
+			s.value = provider.getSetting(setting.id)
+			s.type = setting.type instanceof Function ? setting.type.name : "String"
+			s.isCheckbox = setting.type === Boolean
+			s.isSelect = s.choices !== undefined
+			s.isRange = (setting.type === Number) && s.range
+			s.isColor = false
+			settings.push(s)
+		}
+		catch (e) {
+			console.warn(`Drag Ruler | The following error occured while rendering setting "${setting.id}" of module/system "${this.id}. It won't be displayed.`)
+			console.error(e)
+		}
+	}
+
+	return settings.concat(colorSettings)
+}

js/socket.js

@@ -0,0 +1,43 @@
+import {currentSpeedProvider} from "./api.js";
+
+let socket;
+
+Hooks.once("socketlib.ready", () => {
+	socket = socketlib.registerModule("drag-ruler");
+	socket.register("updateCombatantDragRulerFlags", _socketUpdateCombatantDragRulerFlags);
+	socket.register("recalculate", _socketRecalculate);
+});
+
+export function updateCombatantDragRulerFlags(combat, updates) {
+	const combatId = combat.id;
+	// TODO Check if canvas.tokens.get is still neccessary in future foundry versions
+	return socket.executeAsGM(_socketUpdateCombatantDragRulerFlags, combatId, updates)
+	             .then(() => currentSpeedProvider.onMovementHistoryUpdate(updates.map(update => canvas.tokens.get(combat.combatants.get(update._id).token.id))));
+}
+
+async function _socketUpdateCombatantDragRulerFlags(combatId, updates) {
+	const user = game.users.get(this.socketdata.userId);
+	const combat = game.combats.get(combatId);
+	const requestedUpdates = updates.length;
+	updates = updates.filter(update => {
+		const actor = combat.combatants.get(update._id).actor;
+		if (!actor)
+			return false;
+		return actor.testUserPermission(user, "OWNER");
+	});
+	if (updates.length !== requestedUpdates) {
+		console.warn(`Some of the movement history updates requested by user '${game.users.get(this.socketdata.userId).name}' were not performed because the user lacks owner permissions for those tokens`);
+	}
+	updates = updates.map(update => {
+		return {_id: update._id, flags: {dragRuler: update.dragRulerFlags}};
+	});
+	await combat.updateEmbeddedDocuments("Combatant", updates, {diff: false});
+}
+
+export function recalculate(tokens) {
+	socket.executeForEveryone(_socketRecalculate, tokens ? tokens.map(token => token.id) : undefined);
+}
+
+function _socketRecalculate(tokenIds) {
+	return canvas.controls.ruler.dragRulerRecalculate(tokenIds);
+}

js/speed_provider.js

@@ -0,0 +1,173 @@
+import {settingsKey} from "./settings.js"
+import {getDefaultDashMultiplier, getDefaultSpeedAttribute} from "./systems.js"
+
+/**
+ * Base class for all speed providers.
+ * If you want to offer a speed provider in your system/module you must derive this class.
+ * Each speed provider must at least implement
+ */
+export class SpeedProvider {
+	/**
+	 * Returns an array of colors used by this speed provider. Each color corresponds to one speed that a token may have.
+	 * Each color must be an object with the following properties:
+	 * - id: A value that identfies the color. Must be unique for each color returned.
+	 * - default: The color that is used to highlight that speed by default.
+	 * - name: A user readable name for the speed represented by the color. This name is used in the color configuration dialog. Drag Ruler will attempt to localize this string using `game.i18n`
+	 *
+	 * Of these properties, id and defaultColor are required. name is optional, but it's recommended to set it
+	 *
+	 * Implementing this method is required for all speed providers
+	 */
+	get colors() {
+		throw new Error("A SpeedProvider must implement the colors function")
+	}
+
+	/**
+	 * Returns an array of speeds that the token passed in the arguments this token can reach.
+	 * Each range is an object that with the following properties:
+	 * - range: A number indicating the distance that the token can travel with this speed
+	 * - color: The id (as defined in the `colors` getter) of the color that should be used to represent this range
+	 *
+	 * Implementing this method is required for all speed providers
+	 */
+	getRanges(token) {
+		throw new Error("A SpeedProvider must implement the getRanges function")
+	}
+
+	/**
+	 * Returns an array of configuration options for this module. The settings will be shown in the Speed Provider Settings of Drag Ruler.
+	 * Each configuration option is an object that has the same attributes as a native foundry setting passed to `game.settings.register`,
+	 * except for these exceptions:
+	 * - id: A string that identifies the setting. Must be unique for each setting returned. This id will be used to fetch the setting.
+	 * - config: This property is not supported by Drag Ruler module settings. Use foundries native settings instead if you need settings that don't show up in the configuration dialog.
+	 *
+	 * Implementing this method is optional and only needs to be done if you want to provide custom provider settings
+	 */
+	get settings() {
+		return []
+	}
+
+	/**
+	 * Returns the default color for ranges that a token cannot reach.
+	 *
+	 * Implementing this method is optional and only needs to be done if you want to provide a custom default for that color.
+	 */
+	get defaultUnreachableColor() {
+		return 0xFF0000
+	}
+
+	/**
+	 * Returns the cost for a token to step into the specificed area.
+	 * The area indicates the whole area that the token will occupy (for tokens larger than 1x1) the array will more than one entry.
+	 * The return value should be an integer indicating a multiplicator by that the cost of that step should be increased.
+	 * (1 is regular cost, 2 costs double, 3 costs triple, ...)
+	 *
+	 * Parameters:
+	 * - options: An object used to configure Enhanced Terrain Layer's cost calculation. Ex: If options.ignoreGrid is set to true, then Euclidean measurement can be forced on a gridded map.
+	 *
+	 * This function is only called if the Enhanced Terrain Layer and Terrain Ruler modules are enabled.
+	 *
+	 * Implementing this method is optional and only needs to be done if you want to provide a custom cost function (for example to allow tokens to ignore difficult terrain)
+	 */
+	getCostForStep(token, area, options={}) {
+		// Lookup the cost for each square occupied by the token
+		options.token = token;
+		const costs = area.map(space => terrainRuler.getCost(space.x, space.y, options));
+		// Return the maximum of the costs
+		return costs.reduce((max, current) => Math.max(max, current))
+	}
+
+	/**
+	 * Returns a boolean indicating whether this token will use a Ruler or not.
+	 * If this is returns `false` for a token Drag Ruler will be disabled for that token. Dragging a token for which this function
+	 * returns false will behave as if Drag Ruler wasn't installed.
+	 * If usesRuler returns `false` it's guranteed that the `getRanges` function won't be called for that token.
+	 *
+	 * Implementing this method is optional and only needs to be done if you want to disable Drag Ruler for some tokens.
+	 */
+	usesRuler(token) {
+		return true
+	}
+
+	/**
+	 * This hook is being called after Drag Ruler has updated the movement history for one or more tokens.
+	 * It'll receive an array of tokens that have been updated.
+	 * If your speed provider is storing any additional values that are relevant for the movement history, this function should
+	 * await until those updates have completed inside foundry.
+	 */
+	async onMovementHistoryUpdate(tokens) {}
+
+	/**
+	 * Returns the value that is currently set for the setting registered with the provided settingId.
+	 *
+	 * This function shouldn't be overridden by speed provider implementations. It can be called to fetch speed provider specific settings.
+	 */
+	getSetting(settingId) {
+		try {
+			return game.settings.get(settingsKey, `speedProviders.${this.id}.setting.${settingId}`)
+		}
+		catch (e) {
+			if (this.settings.some(setting => setting.id === settingId)) {
+				throw e
+			}
+			throw new Error(`Drag Ruler | "${settingId}" is not a registered setting for "${this.id}". If you're the module/system developer, please add it to the return values of your Speed Providers "get settings()" function.`)
+		}
+	}
+
+	/**
+	 * Constructs a new instance of he speed provider
+	 *
+	 * This function should neither be called or overridden by speed provider implementations
+	 */
+	constructor(id) {
+		this.id = id
+	}
+}
+
+
+export class GenericSpeedProvider extends SpeedProvider {
+	get colors() {
+		return [
+			{id: "walk", default: 0x00FF00, name: "drag-ruler.genericSpeedProvider.speeds.walk"},
+			{id: "dash", default: 0xFFFF00, name: "drag-ruler.genericSpeedProvider.speeds.dash"}
+		]
+	}
+
+	getRanges(token) {
+		const speedAttribute = this.getSetting("speedAttribute")
+		if (!speedAttribute)
+			return []
+		const tokenSpeed = parseFloat(getProperty(token, speedAttribute));
+		if (tokenSpeed === undefined) {
+			console.warn(`Drag Ruler (Generic Speed Provider) | The configured token speed attribute "${speedAttribute}" didn't return a speed value. To use colors based on drag distance set the setting to the correct value (or clear the box to disable this feature).`)
+			return []
+		}
+		const dashMultiplier = this.getSetting("dashMultiplier")
+		if (!dashMultiplier)
+			return [{range: tokenSpeed, color: "walk"}]
+		return [{range: tokenSpeed, color: "walk"}, {range: tokenSpeed * dashMultiplier, color: "dash"}]
+	}
+
+	get settings() {
+		return [
+			{
+				id: "speedAttribute",
+				name: "drag-ruler.genericSpeedProvider.settings.speedAttribute.name",
+				hint: "drag-ruler.genericSpeedProvider.settings.speedAttribute.hint",
+				scope: "world",
+				config: true,
+				type: String,
+				default: getDefaultSpeedAttribute(),
+			},
+			{
+				id: "dashMultiplier",
+				name: "drag-ruler.genericSpeedProvider.settings.dashMultiplier.name",
+				hint: "drag-ruler.genericSpeedProvider.settings.dashMultiplier.hint",
+				scope: "world",
+				config: true,
+				type: Number,
+				default: getDefaultDashMultiplier(),
+			}
+		]
+	}
+}

js/systems.js

@@ -0,0 +1,43 @@
+export function getDefaultSpeedAttribute() {
+	switch (game.system.id) {
+		case "CoC7":
+			return "actor.data.data.attribs.mov.value";
+		case "dcc":
+			return "actor.data.data.attributes.speed.value";
+		case "dnd5e":
+			return "actor.data.data.attributes.movement.walk"
+		case "lancer":
+			return "actor.data.data.derived.speed"
+		case "pf1":
+		case "D35E":
+			return "actor.data.data.attributes.speed.land.total"
+		case "sfrpg":
+			return "actor.data.data.attributes.speed.value";
+		case "shadowrun5e":
+			return "actor.data.data.movement.walk.value";
+		case "swade":
+			return "actor.data.data.stats.speed.adjusted";
+		case "ds4":
+			return "actor.data.data.combatValues.movement.total";
+	}
+	return ""
+}
+
+export function getDefaultDashMultiplier() {
+	switch (game.system.id) {
+		case "swade":
+			return 0
+		case "dcc":
+		case "dnd5e":
+		case "lancer":
+		case "pf1":
+		case "D35E":
+		case "sfrpg":
+		case "shadowrun5e":
+		case "ds4":
+			return 2
+		case "CoC7":
+			return 5;
+	}
+	return 0
+}

js/util.js

@@ -0,0 +1,281 @@
+import {getPixelsFromGridPosition} from "./foundry_fixes.js"
+import { disableSnap } from "./keybindings.js";
+
+export function* zip(it1, it2) {
+	for (let i = 0;i < Math.min(it1.length, it2.length);i++) {
+		yield [it1[i], it2[i]]
+	}
+}
+
+export function* enumeratedZip(it1, it2) {
+	let i = 0;
+	for (const [v1, v2] of zip(it1, it2)) {
+		yield [i, v1, v2];
+		i++;
+	}
+}
+
+export function* iterPairs(l) {
+	for (let i = 1;i < l.length;i++) {
+		yield [l[i - 1], l[i]];
+	}
+}
+
+export function sum(arr) {
+	return arr.reduce((a, b) => a + b, 0);
+}
+
+export function getSnapPointForToken(x, y, token) {
+	if (canvas.grid.type === CONST.GRID_TYPES.GRIDLESS) {
+		return new PIXI.Point(x, y);
+	}
+	if (canvas.grid.isHex) {
+		if (game.modules.get("hex-size-support")?.active && CONFIG.hexSizeSupport.getAltSnappingFlag(token)) {
+			if (token.document.getFlag("hex-size-support", "borderSize") % 2 === 0) {
+				const snapPoint = CONFIG.hexSizeSupport.findVertexSnapPoint(x, y, token, canvas.grid.grid)
+				return new PIXI.Point(snapPoint.x, snapPoint.y)
+			}
+			else {
+				return new PIXI.Point(...canvas.grid.getCenter(x, y))
+			}
+		}
+		else {
+			return new PIXI.Point(...canvas.grid.getCenter(x, y));
+		}
+	}
+
+	const [topLeftX, topLeftY] = canvas.grid.getTopLeft(x, y);
+	let cellX, cellY;
+	if (token.data.width % 2 === 0)
+		cellX = x - canvas.grid.h / 2;
+	else
+		cellX = x;
+	if (token.data.height % 2 === 0)
+		cellY = y - canvas.grid.h / 2;
+	else
+		cellY = y;
+	const [centerX, centerY] = canvas.grid.getCenter(cellX, cellY);
+	let snapX, snapY;
+	// Tiny tokens can snap to the cells corners
+	if (token.data.width <= 0.5) {
+		const offsetX = x - topLeftX;
+		const subGridWidth = Math.floor(canvas.grid.w / 2);
+		const subGridPosX = Math.floor(offsetX / subGridWidth);
+		snapX = topLeftX + (subGridPosX + 0.5) * subGridWidth;
+	}
+	// Tokens with odd multipliers (1x1, 3x3, ...) and tokens smaller than 1x1 but bigger than 0.5x0.5 snap to the center of the grid cell
+	else if (Math.round(token.data.width) % 2 === 1 || token.data.width < 1) {
+		snapX = centerX;
+	}
+	// All remaining tokens (those with even or fractional multipliers on square grids) snap to the intersection points of the grid
+	else {
+		snapX = centerX + canvas.grid.w / 2;
+	}
+	if (token.data.height <= 0.5) {
+		const offsetY = y - topLeftY;
+		const subGridHeight = Math.floor(canvas.grid.h / 2);
+		const subGridPosY = Math.floor(offsetY / subGridHeight);
+		snapY = topLeftY + (subGridPosY + 0.5) * subGridHeight;
+	}
+	else if (Math.round(token.data.height) % 2 === 1 || token.data.height < 1) {
+		snapY = centerY;
+	}
+	else {
+		snapY = centerY + canvas.grid.h / 2;
+	}
+	return new PIXI.Point(snapX, snapY);
+}
+
+export function getSnapPointForTokenObj(pos, token) {
+	return getSnapPointForToken(pos.x, pos.y, token);
+}
+
+export function getSnapPointForMeasuredTemplate(x, y) {
+	if (canvas.grid.type === CONST.GRID_TYPES.GRIDLESS) {
+		return new PIXI.Point(x, y);
+	}
+	let subgridWidth, subgridHeight;
+	if (canvas.grid.type === CONST.GRID_TYPES.SQUARE) {
+		subgridWidth = subgridHeight = canvas.dimensions.size / 2;
+	}
+	else {
+		if (canvas.grid.grid.columns) {
+			subgridWidth = canvas.grid.w / 4;
+			subgridHeight = canvas.grid.h / 2;
+		}
+		else {
+			subgridWidth = canvas.grid.w / 2;
+			subgridHeight = canvas.grid.h / 4;
+		}
+	}
+	const snappedX = Math.round(x / subgridWidth) * subgridWidth;
+	const snappedY = Math.round(y / subgridHeight) * subgridHeight;
+	return new PIXI.Point(snappedX, snappedY);
+}
+
+export function getSnapPointForEntity(x, y, entity) {
+	const isToken = entity instanceof Token;
+	if (isToken)
+		return getSnapPointForToken(x, y, entity);
+	else
+		return getSnapPointForMeasuredTemplate(x, y);
+}
+
+export function highlightTokenShape(position, shape, color, alpha) {
+	const layer = canvas.grid.highlightLayers[this.name];
+    if ( !layer )
+		return false;
+	const area = getAreaFromPositionAndShape(position, shape);
+	for (const space of area) {
+		const [x, y] = getPixelsFromGridPosition(space.x, space.y);
+		canvas.grid.grid.highlightGridPosition(layer, {x, y, color, alpha: 0.25 * alpha});
+	}
+}
+
+export function getAreaFromPositionAndShape(position, shape) {
+	return shape.map(space => {
+		let x = position.x + space.x;
+		let y = position.y + space.y;
+		if (canvas.grid.isHex) {
+			let shiftedRow;
+			if (canvas.grid.grid.options.even)
+				shiftedRow = 1
+			else
+				shiftedRow = 0
+			if (canvas.grid.grid.options.columns) {
+				if (space.x % 2 !== 0 && position.x % 2 !== shiftedRow) {
+					y += 1;
+				}
+			}
+			else {
+				if (space.y % 2 !== 0 && position.y % 2 !== shiftedRow) {
+					x += 1;
+				}
+			}
+		}
+		return {x, y}
+	});
+}
+
+export function getTokenShape(token) {
+	if (token.scene.data.gridType === CONST.GRID_TYPES.GRIDLESS) {
+		return [{x: 0, y: 0}]
+	}
+	else if (token.scene.data.gridType === CONST.GRID_TYPES.SQUARE) {
+		const topOffset = -Math.floor(token.data.height / 2)
+		const leftOffset = -Math.floor(token.data.width / 2)
+		const shape = []
+		for (let y = 0;y < token.data.height;y++) {
+			for (let x = 0;x < token.data.width;x++) {
+				shape.push({x: x + leftOffset, y: y + topOffset})
+			}
+		}
+		return shape
+	}
+	else {
+		// Hex grids
+		if (game.modules.get("hex-size-support")?.active && CONFIG.hexSizeSupport.getAltSnappingFlag(token)) {
+			const borderSize = token.data.flags["hex-size-support"].borderSize;
+			let shape = [{x: 0, y: 0}];
+			if (borderSize >= 2)
+				shape = shape.concat([{x: 0, y: -1}, {x: -1, y: -1}]);
+			if (borderSize >= 3)
+				shape = shape.concat([{x: 0, y: 1}, {x: -1, y: 1}, {x: -1, y: 0}, {x: 1, y: 0}]);
+			if (borderSize >= 4)
+				shape = shape.concat([{x: -2, y: -1}, {x: 1, y: -1}, {x: -1, y: -2}, {x: 0, y: -2}, {x: 1, y: -2}])
+
+			if (Boolean(CONFIG.hexSizeSupport.getAltOrientationFlag(token)) !== canvas.grid.grid.options.columns)
+				shape.forEach(space => space.y *= -1);
+			if (canvas.grid.grid.options.columns)
+				shape = shape.map(space => {return {x: space.y, y: space.x}});
+			return shape;
+		}
+		else {
+			return [{x: 0, y: 0}];
+		}
+	}
+}
+
+export function getTokenSize(token) {
+	let w, h;
+	const hexSizeSupportBorderSize = token.data.flags["hex-size-support"]?.borderSize;
+	if (hexSizeSupportBorderSize > 0) {
+		w = h = hexSizeSupportBorderSize
+	}
+	else {
+		w = token.data.width
+		h = token.data.height
+	}
+	return {w, h};
+}
+
+// Tokens that have a size divisible by two (2x2, 4x4, 2x1) have their ruler at the edge of a cell.
+// This function applies an offset to to the waypoints that will move the ruler from the edge to the center of the cell
+export function applyTokenSizeOffset(waypoints, token) {
+	if (canvas.grid.type === CONST.GRID_TYPES.GRIDLESS) {
+		return waypoints
+	}
+
+	const tokenSize = getTokenSize(token);
+	const waypointOffset = {x: 0, y: 0};
+	if (canvas.grid.isHex) {
+		if (game.modules.get("hex-size-support")?.active) {
+			const isAltOrientation = CONFIG.hexSizeSupport.getAltOrientationFlag(token);
+			if (canvas.grid.grid.options.columns) {
+				if (tokenSize.w % 2 === 0) {
+					waypointOffset.x = canvas.grid.w / 2;
+					if (!isAltOrientation)
+						waypointOffset.x *= -1;
+				}
+			}
+			else {
+				if (tokenSize.h % 2 === 0) {
+					waypointOffset.y = canvas.grid.h / 2;
+					if (isAltOrientation)
+						waypointOffset.y *= -1;
+				}
+			}
+		}
+		// If hex size support isn't active leave the waypoints like they are
+	}
+	else {
+		if (tokenSize.w % 2 === 0) {
+			waypointOffset.x = canvas.grid.w / 2;
+		}
+		if (tokenSize.h % 2 === 0) {
+			waypointOffset.y = canvas.grid.h / 2;
+		}
+	}
+
+	return waypoints.map(w => new PIXI.Point(w.x + waypointOffset.x, w.y + waypointOffset.y))
+}
+
+export function setSnapParameterOnOptions(sourceObject, options) {
+	// Allow outside modules to override snapping
+	if (sourceObject.snapOverride?.active) {
+		options.snapOverrideActive = true;
+		options.snap = sourceObject.snapOverride.snap;
+		sourceObject.snapOverride = undefined; // remove it to prevent any lingering data issues
+	}
+	else {
+		options.snap = !disableSnap;
+	}
+}
+
+export function isClose(a, b, delta) {
+	return Math.abs(a - b) <= delta;
+}
+
+export function getMeasurePosition() {
+	const mousePosition = canvas.app.renderer.plugins.interaction.mouse.getLocalPosition(canvas.tokens);
+	const rulerOffset = canvas.controls.ruler.rulerOffset;
+	const measurePosition = {x: mousePosition.x + rulerOffset.x, y: mousePosition.y + rulerOffset.y};
+	return measurePosition;
+}
+
+// isGM function for use during loading when game.user isn't available yet
+export function early_isGM() {
+	const level = game.data.users.find(u => u._id == game.data.userId).role;
+	const gmLevel = CONST.USER_ROLES.ASSISTANT;
+	return level >= gmLevel;
+}