It is discussed that the hidden pollution and its harm of night sceneillumination exists in cities, and some prevention and cure meth-od is put forward by author in this thesis.
介绍了城市夜景照明中的隐性污染，讨论了这种污染的危害，提出了对这种污染的防治方法。
2
This is because, with a broad source, light rays hit your subject from more directions, which tends to fill in shadows and give more even illumination to the scene.
这是因为光源越广，射在物体上光线的方向就越多，这会起到增加场景中的照明、减少阴影的作用。
3
The basic idea is illuminating the scene with the light probe images. To simplify the design of local illumination model, the bidirectional transmit distribution function is introduced.