Explicit edge check

Author: szakarias

pkg/web_app/lib/src/widget/downloads_chart/computations.dart

@@ -132,8 +132,8 @@ bool isPointOnPathWithTolerance(
 /// a polygon defined by a list of vertices. The polygon is assumed to be
 /// closed and non-self-intersecting.
 ///
-/// Returns `true` if the point is inside the polygon or exactly on a vertex and
-/// `false` otherwise.
+/// Returns `true` if the point is inside the polygon or exactly on a vertex or
+/// on edge, and `false` otherwise.
 bool isPointInPolygon(List<(double, double)> polygon, (double, double) point) {
   if (polygon.length < 3) {
     return false;
@@ -142,6 +142,11 @@ bool isPointInPolygon(List<(double, double)> polygon, (double, double) point) {
   int intersections = 0;
   final (px, py) = point;
 
+  // Check if the point is on an edge
+  if (isPointOnPathWithTolerance(polygon, point, 0.001)) {
+    return true;
+  }
+
   for (int i = 0; i < polygon.length; i++) {
     final (x1, y1) = polygon[i];
     final (x2, y2) = polygon[(i + 1) % polygon.length];

pkg/web_app/test/widget/downloads_chart/downloads_chart_test.dart

@@ -212,12 +212,14 @@ void main() {
       final outsidePoint = (2.0, 3.0);
       final vertexPoint = (1.0, 1.0);
       final edgePoint = (1.0, 3.0);
+      final edgePoint2 = (3.0, 3.0);
       final outsidePointOnEdgeExtension = (3.0, 4.0);
 
       expect(isPointInPolygon(complexPolygon, insidePoint), isTrue);
       expect(isPointInPolygon(complexPolygon, outsidePoint), isFalse);
       expect(isPointInPolygon(complexPolygon, vertexPoint), isTrue);
-      expect(isPointInPolygon(complexPolygon, edgePoint), isFalse);
+      expect(isPointInPolygon(complexPolygon, edgePoint), isTrue);
+      expect(isPointInPolygon(complexPolygon, edgePoint2), isTrue);
       expect(isPointInPolygon(complexPolygon, outsidePointOnEdgeExtension),
           isFalse);
     });