feat: demo page realisation

src/client/src/components/map/TravelPath.tsx

@@ -0,0 +1,92 @@
+import { Graphics } from "pixi.js";
+import { useCallback } from "react";
+import { PATH_COLOR, PATH_WIDTH, UNPASSED_STATION_COLOR } from "./Constants";
+
+interface TravelPathProps {
+  points: { x: number; y: number }[];
+  busCoordinates?: { x: number; y: number };
+}
+
+const PASSED_PATH_COLOR = PATH_COLOR;
+const UNPASSED_PATH_COLOR = UNPASSED_STATION_COLOR;
+
+export function TravelPath({
+  points,
+  busCoordinates,
+}: Readonly<TravelPathProps>) {
+  const draw = useCallback(
+    (g: Graphics) => {
+      g.clear();
+
+      if (points.length < 2) {
+        return;
+      }
+
+      g.moveTo(points[0].x, points[0].y);
+      for (let i = 1; i < points.length; i++) {
+        g.lineTo(points[i].x, points[i].y);
+      }
+      g.stroke({
+        color: UNPASSED_PATH_COLOR,
+        width: PATH_WIDTH,
+      });
+
+      if (!busCoordinates) {
+        return;
+      }
+
+      let minDistance = Infinity;
+      let closestSegmentIndex = -1;
+      let busSegmentStartPoint: { x: number; y: number } | null = null;
+
+      for (let i = 0; i < points.length - 1; i++) {
+        const p1 = points[i];
+        const p2 = points[i + 1];
+
+        const lineLengthSq = (p2.x - p1.x) ** 2 + (p2.y - p1.y) ** 2;
+        if (lineLengthSq === 0) continue;
+
+        const t =
+          ((busCoordinates.x - p1.x) * (p2.x - p1.x) +
+            (busCoordinates.y - p1.y) * (p2.y - p1.y)) /
+          lineLengthSq;
+        const projectionT = Math.max(0, Math.min(1, t));
+
+        const projectedX = p1.x + projectionT * (p2.x - p1.x);
+        const projectedY = p1.y + projectionT * (p2.y - p1.y);
+
+        const dist = Math.sqrt(
+          (busCoordinates.x - projectedX) ** 2 +
+            (busCoordinates.y - projectedY) ** 2
+        );
+
+        if (dist < minDistance) {
+          minDistance = dist;
+          closestSegmentIndex = i;
+          busSegmentStartPoint = { x: projectedX, y: projectedY };
+        }
+      }
+
+      if (closestSegmentIndex !== -1 && busSegmentStartPoint) {
+        g.moveTo(points[0].x, points[0].y);
+        for (let i = 1; i <= closestSegmentIndex; i++) {
+          g.lineTo(points[i].x, points[i].y);
+        }
+        g.lineTo(busSegmentStartPoint.x, busSegmentStartPoint.y);
+
+        g.stroke({
+          color: PASSED_PATH_COLOR,
+          width: PATH_WIDTH,
+        });
+      }
+    },
+    [points, busCoordinates]
+  );
+
+  if (points.length === 0) {
+    console.error("points is empty");
+    return null;
+  }
+
+  return <pixiGraphics draw={draw} />;
+}