From 286aaf7adabb6923531bdf878f36e9d1c1c812ff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20V=C3=B6gele?= <develop@manuel-voegele.de>
Date: Tue, 11 May 2021 19:01:51 +0200
Subject: [PATCH] Properly store terrain ruler's state in the movement history

---
 CHANGELOG.md             | 3 +++
 src/compatibility.js     | 9 +++++----
 src/foundry_imports.js   | 4 +++-
 src/movement_tracking.js | 4 ++--
 4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6777dec..4042349 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,9 @@
 ### New features
 - Drag Ruler can now measure difficult terrain on gridless maps (if the Terrain Ruler module is installed and enabled)
 
+### Bugfixes
+- Fixed a bug that sometimes measured diagonals incorrectly with the 5/10/5 grid rule
+
 ### Translation
 - Corrected typos in the german translation (thanks to CarnVanBeck!)
 
diff --git a/src/compatibility.js b/src/compatibility.js
index 6e80fb6..9ce5ab4 100644
--- a/src/compatibility.js
+++ b/src/compatibility.js
@@ -15,10 +15,12 @@ export function highlightMeasurementTerrainRuler(ray, startDistance, tokenShape=
 	}
 }
 
-export function measureDistances(segments, token, shape, gridSpaces=true, options={}) {
+export function measureDistances(segments, token, shape, options={}) {
 	const opts = duplicate(options)
-	opts.gridSpaces = gridSpaces;
+	if (!opts.gridSpaces)
+		opts.gridSpaces = true;
 	const terrainRulerAvailable = game.modules.get("terrain-ruler")?.active && (!game.modules.get("TerrainLayer")?.active || canvas.grid.type !== CONST.GRID_TYPES.GRIDLESS);
+
 	if (terrainRulerAvailable) {
 		const firstNewSegmentIndex = segments.findIndex(segment => !segment.ray.dragRulerVisitedSpaces);
 		const previousSegments = segments.slice(0, firstNewSegmentIndex);
@@ -27,7 +29,7 @@ export function measureDistances(segments, token, shape, gridSpaces=true, option
 		previousSegments.forEach(segment => segment.ray.terrainRulerVisitedSpaces = duplicate(segment.ray.dragRulerVisitedSpaces));
 		opts.costFunction = (x, y) => getCostFromSpeedProvider(token, getAreaFromPositionAndShape({x, y}, shape), {x, y});
 		if (previousSegments.length > 0)
-			opts.terrainRulerInitialState = previousSegments[previousSegments.length - 1];
+			opts.terrainRulerInitialState = previousSegments[previousSegments.length - 1].ray.dragRulerFinalState;
 		return distances.concat(terrainRuler.measureDistances(newSegments, opts));
 	}
 	else {
@@ -83,4 +85,3 @@ export function checkDependencies() {
 		}
 	}
 }
-
diff --git a/src/foundry_imports.js b/src/foundry_imports.js
index c3c39f5..720e6cb 100644
--- a/src/foundry_imports.js
+++ b/src/foundry_imports.js
@@ -156,6 +156,8 @@ export function measure(destination, {gridSpaces=true, snap=false} = {}) {
 		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;
@@ -168,7 +170,7 @@ export function measure(destination, {gridSpaces=true, snap=false} = {}) {
 	const shape = getTokenShape(this.draggedToken)
 
 	// Compute measured distance
-	const distances = measureDistances(centeredSegments, this.draggedToken, shape, gridSpaces);
+	const distances = measureDistances(centeredSegments, this.draggedToken, shape, {gridSpaces});
 
 	let totalDistance = 0;
 	for (let [i, d] of distances.entries()) {
diff --git a/src/movement_tracking.js b/src/movement_tracking.js
index 03e078d..5bcb795 100644
--- a/src/movement_tracking.js
+++ b/src/movement_tracking.js
@@ -56,9 +56,9 @@ function calculateUpdate(combat, token, 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), true, {terrainRulerInitialState: dragRulerFlags.rulerState});
+				measureDistances([{ray}], token, getTokenShape(token), {terrainRulerInitialState: waypoints[waypoints.length - 1]?.dragRulerFinalState});
 				ray.A.dragRulerVisitedSpaces = ray.terrainRulerVisitedSpaces;
-				dragRulerFlags.rulerState = ray.terrainRulerFinalState;
+				ray.A.dragRulerFinalState = ray.terrainRulerFinalState;
 			}
 			waypoints.push(ray.A);
 		}