Unstable 1.2.4.0

Barotrauma/BarotraumaShared/SharedSource/Utils/Shapes/Triangle2D.cs

@@ -0,0 +1,21 @@
+using Microsoft.Xna.Framework;
+
+namespace Barotrauma;
+
+readonly record struct Triangle2D(Vector2 A, Vector2 B, Vector2 C)
+{
+    public bool Contains(Vector2 point)
+    {
+        // Get the half-plane that the point lands in, for each side of the triangle
+        int halfPlaneAb = MathUtils.VectorOrientation(A, B, point);
+        int halfPlaneBc = MathUtils.VectorOrientation(B, C, point);
+        int halfPlaneCa = MathUtils.VectorOrientation(C, A, point);
+
+        // The intersection of three half-planes derived from the three sides of the triangle
+        // is the triangle itself, so check for the point being in those three half-planes
+        bool allNonNegative = halfPlaneAb >= 0 && halfPlaneBc >= 0 && halfPlaneCa >= 0;
+        bool allNonPositive = halfPlaneAb <= 0 && halfPlaneBc <= 0 && halfPlaneCa <= 0;
+
+        return allNonNegative || allNonPositive;
+    }
+}