Q84：层级实例网格[Hierarchical Instance Grids]
发布时间：2023-07-04 11:00
通过层级实例网格[Hierarchical Instance Grids]可以在场景中画很多很多个图形。
比如：
![Q84：层级实例网格[Hierarchical Instance Grids]_第1张图片](https://img.it610.com/image/info8/55525b6420bd4e9283092058001a5b80.jpg)
最左边的bunny是一个Grid，可以看作一个基本几何图形。
然后，通过平移在3x3的规则网格中创建9个实例。
然后，这9个实例组成的Grid又可以看作一个基本图形，然后以此可以创建9个这样的‘‘9个实例组成的Grid’’实例......
经过n次实例，则可以创建[3x3]的n次方个bunny。
相关代码截图如下：
![Q84：层级实例网格[Hierarchical Instance Grids]_第2张图片](https://img.it610.com/image/info8/d386520b22fc44cc8b240897959a83a9.png)
![Q84：层级实例网格[Hierarchical Instance Grids]_第3张图片](https://img.it610.com/image/info8/6b2fb3aada444e369c5aef6a64ac2b2e.jpg)
![Q84：层级实例网格[Hierarchical Instance Grids]_第4张图片](https://img.it610.com/image/info8/804c1559d9bf43cc892b69f32c1031f6.png)
![Q84：层级实例网格[Hierarchical Instance Grids]_第5张图片](https://img.it610.com/image/info8/a842ae88e40740168613d2782e3f6da4.jpg)
相关测试图形如下：
![Q84：层级实例网格[Hierarchical Instance Grids]_第6张图片](https://img.it610.com/image/info8/78c033b97afe4a5f9f5ea5ee22acb977.png)
接下来贴的图形是如上表格所列从下往上的次序。
bunny-gap0.08-distance1400-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第7张图片](https://img.it610.com/image/info8/5ae8d00549dd4fcfb020a988da910d96.jpg)
bunny-gap0.08-distance140000-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第8张图片](https://img.it610.com/image/info8/03452240f8b141f99bad1540b1038886.jpg)
bunny-gap0.08-distance14000000-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第9张图片](https://img.it610.com/image/info8/2977582e8dcd4972881dd768542b702b.jpg)
bunny-gap0.08-distance300000000-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第10张图片](https://img.it610.com/image/info8/9b4c866c8c164795b4fe69f14bdb0336.jpg)
dragon-gap0.08-distance300000000-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第11张图片](https://img.it610.com/image/info8/ebbc291fa51f43959467412191ca4066.jpg)
dragon-gap0.16-distance900000000-500,400
![Q84：层级实例网格[Hierarchical Instance Grids]_第12张图片](https://img.it610.com/image/info8/b4040d4dedc0472bb136ec56602b65f6.jpg)
dragon-gap0.16-distance900000000-1024,1024
![Q84：层级实例网格[Hierarchical Instance Grids]_第13张图片](https://img.it610.com/image/info8/8a0ef25f6ba541a9b82b5f0878d3778e.jpg)
dragon-gap0.16-distance1200000000-1024,1024
![Q84：层级实例网格[Hierarchical Instance Grids]_第14张图片](https://img.it610.com/image/info8/020b65bf988b4dfba97f8231f1cd0661.jpg)
相关代码：
http://download.csdn.net/detail/libing_zeng/9779408
参考书籍：
[1]. Kevin Suffern, Ray Tracing from theGround Up, A K Peters Ltd, 2007.