Add support for difficult terrain via Terrain Ruler module (resolves #1)

src/compatibility.js

@@ -1,3 +1,6 @@
+import {getPixelsFromGridPosition} from "./foundry_fixes.js"
+import {getColorForDistance} from "./main.js"
+
 export function getHexSizeSupportTokenGridCenter(token) {
 	const tokenCenterOffset = CONFIG.hexSizeSupport.getCenterOffset(token)
 	const tokenCenter = {x: token.x + tokenCenterOffset.x, y: token.y + tokenCenterOffset.y}
@@ -17,3 +20,11 @@ export function getHexSizeSupportTokenGridCenter(token) {
 	}
 	return tokenCenter
 }
+
+export function highlightMeasurementTerrainRuler(ray, startDistance) {
+	for (const space of ray.terrainRulerVisitedSpaces) {
+		const [x, y] = getPixelsFromGridPosition(space.x, space.y);
+		const color = getColorForDistance.call(this, startDistance, space.distance)
+		canvas.grid.highlightPosition(this.name, {x, y, color: color})
+	}
+}