Touhou/client/Assets/Game/Scripts/Util/Shape/UtilShape.cs

using UnityEngine;

namespace Game
{
    public static class UtilShape
    {
        public static bool IsOverlap(Shape shape, Vector3 shapePos, Vector3 shapeDir, Shape circle, Vector3 circlePos)
        {
            if (circle.Type != EShapeType.Circle)
            {
                Util.Print("第二个形状参数必须为圆形:", circle.Type);
                return false;
            }

            //检查Y
            var (shapeYMin, shapeYMax) = (shapePos.y, shapePos.y + shape.Height);
            var (circleYMin, circleYMax) = (circlePos.y, circlePos.y + circle.Height);

            if (shapeYMin > circleYMax || shapeYMax < circleYMin)
            {
                return false;
            }

            //保底距离
            var distance = Vector3.Distance(shapePos, circlePos);
            if (distance < 0.01f)
            {
                return true;
            }

            //检查AABB
            var (shapeAABB, circleAABB) = (shape.GetAABB(shapeDir), circle.GetAABB(Vector3.zero));
            var shapeXMin = shapeAABB.x + shapePos.x;
            var shapeXMax = shapeAABB.y + shapePos.x;
            var shapeZMin = shapeAABB.z + shapePos.z;
            var shapeZMax = shapeAABB.w + shapePos.z;
            var circleXMin = circleAABB.x + circlePos.x;
            var circleXMax = circleAABB.y + circlePos.x;
            var circleZMin = circleAABB.z + circlePos.z;
            var circleZMax = circleAABB.w + circlePos.z;

            if (shapeXMin > circleXMax || shapeXMax < circleXMin || shapeZMin > circleZMax || shapeZMax < circleZMin)
            {
                return false;
            }

            //检查形状
            Vector3 circleCenterNew;
            switch (shape.Type)
            {
                case EShapeType.Dot:
                    return distance < circle.Radius;
                case EShapeType.Circle:
                    return distance < shape.Radius + circle.Radius;
                case EShapeType.Sector:
                    if (distance > shape.Radius + circle.Radius)
                        return false;
                    circleCenterNew = CircleCenterNew(circlePos, shapePos, shapeDir);
                    return SectorCircle(shape.Radius, shape.Angle, circle.Radius, circleCenterNew);
                case EShapeType.Box:
                    circleCenterNew = CircleCenterNew(circlePos, shapePos, shapeDir);
                    return RectCircle(shape.SizeX, shape.SizeY, circle.Radius, circleCenterNew);
            }

            return false;
        }

        private static Vector3 CircleCenterNew(Vector3 circlePos, Vector3 shapePos, Vector3 shapeDir)
        {
            var dir = circlePos - shapePos;
            return Quaternion.FromToRotation(shapeDir, Vector3.right) * dir;
        }

        private static bool SectorCircle(float radius, float angle, float circleRadius, Vector3 circleCenter)
        {
            if (circleCenter.z < 0)
                circleCenter.z = -circleCenter.z;
            var dist = circleCenter.magnitude; //到原点的距离
            if (dist < circleRadius)
                return true;
            var circleAngle = Mathf.Asin(circleRadius / dist);
            var circleRot = Util.Vec3ToRot(circleCenter);
            return !(circleRot - circleAngle > angle / 2);//边缘情况不管
        }

        private static bool RectCircle(float sizeX, float sizeY, float circleRadius, Vector3 circleCenter)
        {
            var distX = Mathf.Abs(circleCenter.x) - sizeX;
            var distY = Mathf.Abs(circleCenter.z) - sizeY;

            if (distX <= circleRadius && distY <= circleRadius)
            {
                if (distX <= 0f || distY <= 0f)
                {
                    return true;
                }

                var cornerDistanceSquared = Mathf.Pow(distX, 2f) + Mathf.Pow(distY, 2f);
                return cornerDistanceSquared <= Mathf.Pow(circleRadius, 2f);
            }

            return false;
        }
    }
}