游戏引擎中的BoundingBox

霸王•吕布2026-05-27 9:11

一.AABB包围盒

<1.包围盒定义

以长方体盒子形状,长方体顶点为描述的包围盒,在模型,碰撞体创建时同时创建,以实现物理碰撞,特殊shader渲染等常用功能.

center = (min + max) / 2

radius = min到max距离/2

复制代码

public class AABBBoundingBox
{
    public Vector4 min = Vector4.Zero;

    public Vector4 max = Vector4.Zero;

    public Vector4 center = Vector4.Zero;

    public float radius = 0f;
}

<2.包围盒相交物理检测

复制代码

public bool PointInsideBox(Vec3 point, float epsilon)
{
	return point.x + epsilon <= this.max.x 
            && point.x - epsilon >= this.min.x 
            && point.y + epsilon <= this.max.y 
            && point.y - epsilon >= this.min.y 
            && point.z + epsilon <= this.max.z 
            && point.z - epsilon >= this.min.z;
}

二.OBB包围盒

<1.包围盒定义

以长方体盒子形状,局部坐标系三个坐标轴向量进行描述的包围盒.

复制代码

public class OBBBoundingBox
{
   public Vector4 s = new Vector4(1f, 0f, 0f, 0f);

   public Vector4 f = new Vector4(0f, 1f, 0f, 0f);

   public Vector4 u = new Vector4(0f, 0f, 1f, 0f);
}