所以如果你諗下攝影機睇到嘅光 係會從四方八面射出嚟嘅話 就會嚟到一個重點 我可以喺一個特定空間裏面 得到幾多光點 ？
So if you think about the light that the camera is seeing coming out in all directions, it comes to the point: how many points of light can I get in a particular space?