Make tokens snap to their speed ranges on gridless scenes (resolves #71)

lang/de.json

@@ -81,6 +81,10 @@
 			"swapSpacebarRightClick": {
 				"name": "Leertaste und Rechtsklick tauschen",
 				"hint": "Die Funktionen der Leertaste und des Rechtsklicks sind, während eine Spielfigur bewegt wird, vertauscht. Wenn diese Option aktiviert wird können mit Rechtsklick Wegpunkte gesetzt werden und mit der Leertaste werden sie wieder gelöscht."
+			},
+			"useGridlessraster": {
+				"name": "Geschwindigkeitsraster aktivieren",
+				"hint": "Lässt Spielfiguren auf gitterlosen Szenen an deren Geschwindigkeitsgrenzen einrasten."
 			}
 		}
 	}

lang/en.json

@@ -81,6 +81,10 @@
 			"swapSpacebarRightClick": {
 				"name": "Swap spacebar and right click",
 				"hint": "Swaps the functions of spacebar and right click during dragging. If enabled right click will place waypoints and spacebar will delete them"
+			},
+			"useGridlessRaster": {
+				"name": "Use speed based snapping",
+				"hint": "On Gridless scenes, this makes tokens snap to the token's speed ranges"
 			}
 		}
 	}

src/main.js

@@ -1,7 +1,7 @@
 "use strict"
 
-import {currentSpeedProvider, getColorForDistanceAndToken, getMovedDistanceFromToken, initApi, registerModule, registerSystem} from "./api.js";
-import {checkDependencies, getHexSizeSupportTokenGridCenter} from "./compatibility.js";
+import {currentSpeedProvider, getColorForDistanceAndToken, getMovedDistanceFromToken, getRangesFromSpeedProvider, initApi, registerModule, registerSystem} from "./api.js";
+import {checkDependencies, getHexSizeSupportTokenGridCenter, highlightMeasurementTerrainRuler} from "./compatibility.js";
 import {moveEntities, onMouseMove} from "./foundry_imports.js"
 import {performMigrations} from "./migration.js"
 import {DragRulerRuler} from "./ruler.js";
@@ -66,6 +66,8 @@ function hookDragHandlers(entityType) {
 
 	const originalDragLeftMoveHandler = entityType.prototype._onDragLeftMove
 	entityType.prototype._onDragLeftMove = function (event) {
+		if (entityType === Token)
+			applyGridlessSnapping.call(this, event);
 		originalDragLeftMoveHandler.call(this, event)
 		onEntityLeftDragMove.call(this, event)
 	}
@@ -266,3 +268,71 @@ function onEntityDragLeftCancel(event) {
 	}
 	return true
 }
+
+function applyGridlessSnapping(event) {
+	const ruler = canvas.controls.ruler;
+	if (!game.settings.get(settingsKey, "useGridlessRaster"))
+		return;
+	if (!ruler.isDragRuler)
+		return;
+	if (game.keyboard.isDown("Shift"))
+		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;
+			}
+		}
+	}
+}

src/settings.js

@@ -29,6 +29,15 @@ export function registerSettings() {
 		default: false,
 	})
 
+	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",