Improve Pathfinding: Add background caching (#175)

js/hex_support.js

@@ -0,0 +1,93 @@
+/**
+ * Functions taken directly from the hex-size-support module (https://github.com/Ourobor/Hex-Size-Support/releases/tag/1.1.0).
+ * Unless otherwise stated, these functions are taken as-is.
+ */
+
+/**
+ * Altered version of this function.
+ * - Instead of taking a token as a parameter to retrieve the altOrientationFlag, receive the flag value directly
+ * - Instead of taking a grid parameter, get the grid value from the globas canvas
+ */
+export function findVertexSnapPoint(x, y, altOrientationFlag) {
+	const grid = canvas.grid.grid;
+	if (grid.columns) {
+		return findSnapPointCols(x, y, grid.h, grid.w, altOrientationFlag);
+	} else {
+		return findSnapPointRows(x, y, grid.h, grid.w, altOrientationFlag);
+	}
+}
+
+function findSnapPointRows(x, y, h, w, alt) {
+	let xOffset = 0.0
+	if (canvas.grid.grid.even) {
+		xOffset = -0.5
+	}
+
+	let yOffset1 = 0.75
+	let yOffset2 = 0.00
+	if (alt) {
+		yOffset1 = 0.25
+		yOffset2 = 1.00
+	}
+
+	let row1 = calculateSnapPointsRows(x, y, h, w, 0.5 + xOffset, yOffset1);
+	let row2 = calculateSnapPointsRows(x, y, h, w, 1.0 + xOffset, yOffset2);
+
+	let dist1 = Math.pow((row1.x - x), 2) + Math.pow((row1.y - y), 2)
+	let dist2 = Math.pow((row2.x - x), 2) + Math.pow((row2.y - y), 2)
+
+	if (dist1 < dist2) {
+		return row1
+	}
+	else {
+		return row2
+	}
+}
+
+function calculateSnapPointsRows(x, y, h, w, xOff, yOff) {
+	let c = Math.floor(((x + ((0.5 - xOff) * w)) / w) + 1)
+	let r = Math.floor(((y + ((0.75 - yOff) * h)) / (1.5 * h)) + 1)
+
+	let snapX = (c * w) - ((1 - xOff) * w)
+	let snapY = (r * h * 1.5) - ((1.5 - yOff) * h)
+
+	return {x: snapX, y: snapY}
+}
+
+function findSnapPointCols(x, y, h, w, alt) {
+	let yOffset = 0.0
+	if (canvas.grid.grid.even) {
+		yOffset = -0.5
+	}
+
+	let xOffset1 = 0.25
+	let xOffset2 = 1.00
+	if (alt) {
+		xOffset1 = 0.75
+		xOffset2 = 0.00
+	}
+
+	let row1 = calculateSnapPointsCols(x, y, h, w, xOffset1, 0.5 + yOffset);
+	let row2 = calculateSnapPointsCols(x, y, h, w, xOffset2, 1.0 + yOffset);
+
+	let dist1 = Math.pow((row1.x - x), 2) + Math.pow((row1.y - y), 2)
+	let dist2 = Math.pow((row2.x - x), 2) + Math.pow((row2.y - y), 2)
+
+	if (dist1 < dist2) {
+		return row1
+	}
+	else {
+		return row2
+	}
+
+}
+
+function calculateSnapPointsCols(x, y, h, w, xOff, yOff) {
+	let c = Math.floor(((x + ((0.75 - xOff) * w)) / (1.5 * w)) + 1)
+	let r = Math.floor(((y + ((0.5 - yOff) * h)) / h) + 1)
+
+	let snapX = (c * w * 1.5) - ((1.5 - xOff) * w)
+	let snapY = (r * h) - ((1 - yOff) * h)
+
+	return {x: snapX, y: snapY}
+}