/// <summary>
/// max
/// 6 --------- 7
/// / | / |
/// 2 --------- 3 |
/// | | | |
/// | | | |
/// | 4 --------- 5
/// | / | /
/// 0 --------- 1
/// min
/// </summary>
public static void DrawAABB(Vector3 Min, Vector3 Max, int level)
{
int idx = level % Colors.Length;
// 6个面
// 8顶点索引和数据对应
Vector3[] vxt = new Vector3[8];
vxt[0] = new Vector3(Min[0], Min[1], Min[2]);
vxt[1] = new Vector3(Max[0], Min[1], Min[2]);
vxt[2] = new Vector3(Min[0], Max[1], Min[2]);
vxt[3] = new Vector3(Max[0], Max[1], Min[2]);
vxt[4] = new Vector3(Min[0], Min[1], Max[2]);
vxt[5] = new Vector3(Max[0], Min[1], Max[2]);
vxt[6] = new Vector3(Min[0], Max[1], Max[2]);
vxt[7] = new Vector3(Max[0], Max[1], Max[2]);
List <Vector3> polygon = new List <Vector3>();
// 近
polygon.Add(vxt[0]);
polygon.Add(vxt[1]);
polygon.Add(vxt[3]);
polygon.Add(vxt[2]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
// 左
polygon.Clear();
polygon.Add(vxt[0]);
polygon.Add(vxt[4]);
polygon.Add(vxt[6]);
polygon.Add(vxt[2]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
// 底
polygon.Clear();
polygon.Add(vxt[0]);
polygon.Add(vxt[1]);
polygon.Add(vxt[5]);
polygon.Add(vxt[4]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
// 右
polygon.Clear();
polygon.Add(vxt[1]);
polygon.Add(vxt[5]);
polygon.Add(vxt[7]);
polygon.Add(vxt[3]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
// 远
polygon.Clear();
polygon.Add(vxt[4]);
polygon.Add(vxt[5]);
polygon.Add(vxt[7]);
polygon.Add(vxt[6]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
// 上
polygon.Clear();
polygon.Add(vxt[2]);
polygon.Add(vxt[3]);
polygon.Add(vxt[7]);
polygon.Add(vxt[6]);
GeoDebugDrawUtils.DrawPolygon(polygon, Colors[idx]);
}
/// <summary>
/// 根据相机位置,获得所在区域,然后获取Box可见面构造的轮廓
/// max
/// 6 --------- 7
/// / | / |
/// 2 --------- 3 |
/// | | | |
/// | | | |
/// | 4 --------- 5
/// | / | /
/// 0 --------- 1
/// min
/// </summary>
/// <param name="box">查询Box的可见性</param>
/// <returns></returns>
private int QueryBox(ref OOBox box)
{
Vector3 min = box.Min;
Vector3 max = box.Max;
// 8顶点索引和数据对应
Vector4[] vxt = new Vector4[8];
vxt[0] = new Vector4(min[0], min[1], min[2], 1);
vxt[1] = new Vector4(max[0], min[1], min[2], 1);
vxt[2] = new Vector4(min[0], max[1], min[2], 1);
vxt[3] = new Vector4(max[0], max[1], min[2], 1);
vxt[4] = new Vector4(min[0], min[1], max[2], 1);
vxt[5] = new Vector4(max[0], min[1], max[2], 1);
vxt[6] = new Vector4(min[0], max[1], max[2], 1);
vxt[7] = new Vector4(max[0], max[1], max[2], 1);
// 区域码计算
int cd = 0;
if (mPosition[0] < min[0])
{
// 左面之左
cd |= 1;
}
if (mPosition[0] > max[0])
{
// 右面之右
cd |= 2;
}
if (mPosition[1] < min[1])
{
// 下面之下
cd |= 4;
}
if (mPosition[1] > max[1])
{
// 上面之上
cd |= 8;
}
if (mPosition[2] < min[2])
{
// 进面之近
cd |= 16;
}
if (mPosition[2] > max[2])
{
// 远面之远
cd |= 32;
}
// 到这一步,已经过了截头体测试.物体均在相机视角内
// 索引相机能见到的顶点
int[] stt = STAB[cd];
// 数组0索引表示能见到的顶点数量,后面的数组索引记录Box的顶点索引
int vp = stt[0];
#if TEST_DRAW
List <Vector3> polygon = new List <Vector3>();
List <Vector3> clipPolygon = new List <Vector3>();
#endif
// 遍历顶点
for (int i = 0; i < vp; i++)
{
// 获得顶点索引
int j = stt[i + 1];
// 将顶点变换到裁剪空间
mClip.mClipSpaceVertices[i] = mPV * vxt[j];
#if TEST_DRAW
polygon.Add(vxt[j]);
// 裁剪前
clipPolygon.Add(mClip.mClipSpaceVertices[i] * (1 / mClip.mClipSpaceVertices[i][3]));
#endif
}
#if TEST_DRAW
// 绘制可见多边形
GeoDebugDrawUtils.DrawPolygon(polygon, Color.red);
GeoDebugDrawUtils.DrawPolygon(clipPolygon, Color.red);
DrawNDCBox();
#endif
// 对Box的轮廓进行裁剪计算,返回裁剪后的顶点数
vp = mClip.ClipAndProject(vp);
#if TEST_DRAW
clipPolygon.Clear();
// z 方向上 偏移 0.01
Vector4 offset = new Vector4(0, 0, 0.01f, 0);
for (int i = 0; i < vp; ++i)
{
clipPolygon.Add(offset + mClip.mClipSpaceVertices[i]);
}
// 裁剪后
GeoDebugDrawUtils.DrawPolygon(clipPolygon, Color.blue);
#endif
if (vp < 3)
{
return(0);
}
int res = Map.QueryPolygon(mClip.mScreenSpaceVertices, vp);
return(res);
}
public void DrawAABB()
{
GeoDebugDrawUtils.DrawAABB(Box.Min, Box.Max, Level);
}
