* raycast

1 files changed, 86 insertions, 0 deletions

diff --git a/marching/Assets/Scripts/Physics/PhysicsManager_CollisionDetection.cs b/marching/Assets/Scripts/Physics/PhysicsManager_CollisionDetection.cs
index a0dcc97..5210767 100644
--- a/marching/Assets/Scripts/Physics/PhysicsManager_CollisionDetection.cs
+++ b/marching/Assets/Scripts/Physics/PhysicsManager_CollisionDetection.cs
@@ -1,7 +1,11 @@
 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
+using static UnityEditor.Rendering.CameraUI;
 
+/// <summary>
+/// Åöײ¼ì²â
+/// </summary>
 public partial class PhysicsManager : Singleton<PhysicsManager>
 {
 
@@ -70,6 +74,88 @@ public partial class PhysicsManager : Singleton<PhysicsManager>
         return Vector2.Dot(u, u) < radius * radius;
     }
 
+    public static bool RayVsCircle(Vector4 ray, Vector3 circle)
+    {
+        Vector4 seg = GetRaySegment(ray);
+        Vector2 dir = ray.zw().normalized;
+        Vector2 center = circle.xy();
+        float u = Vector2.Dot(center - seg.xy(), dir);
+        Vector2 near = new Vector2();
+        if(u <= 0)
+        {
+            near = seg.xy();
+        }
+        else if(u >= ray.zw().magnitude)
+        {
+            near = seg.zw();
+        }
+        else
+        {
+            near = seg.xy() + dir * u;
+        }
+        return (near - center).sqrMagnitude <= circle.z * circle.z;
+    }
+
+
+    // From Real-time Collision Detection, p179
+    // box2d
+    public static bool RayVsBox(Vector4 ray, Vector4 box)
+    {
+        float tmin = float.MinValue;
+        float tmax = float.MaxValue;
+        Vector2 dir = ray.zw().normalized;
+        Vector4 range = GetBoxRange(box); //lowerx,higherx,lowery,highery
+        Vector2 lowerBound = new Vector2(range.x, range.z);
+        Vector2 upperBound = new Vector2(range.y, range.w);
+        //Vector2 normal = new Vector2();
+        Vector2 p = ray.xy();
+
+        for (int i = 0; i < 2; ++i)
+        {
+
+            if (dir[i] < float.Epsilon) // ºÍx-slabƽÐÐ
+            {
+                if (p[i] < lowerBound[i] || p[i] > upperBound[i])
+                {
+                    return false;
+                }
+            }
+            else
+            {
+                float inv_d = 1f / dir[i];
+                float t1 = (lowerBound[i] - p[i]) * inv_d;
+                float t2 = (upperBound[i] - p[i]) * inv_d;
+                float s = -1f;
+                if (t1 > t2)
+                {
+                    MathUtils.Swap(ref t1, ref t2);
+                    s = 1f;
+                }
+                if (t1 > tmin)
+                {
+                    //normal = Vector2.zero;
+                    //normal[i] = s;
+                    tmin = t1;
+                }
+
+                tmax = Mathf.Min(tmax, t2);
+
+                if (tmin > tmax)
+                {
+                    return false;
+                }
+            }
+        }
+
+        if (tmin < 0 || ray.zw().magnitude < tmin)
+            return false;
+        //// Intersection.
+        //output->fraction = tmin;
+        //output->normal = normal;
+
+        return true;
+    }
+
     /// <summary>
     /// box x,y,w,h circle x,y,raduis
     /// </summary>