{"action":"created","issue":{"url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/5","labels_url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/5/labels{/name}","comments_url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/5/comments","events_url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/5/events","html_url":"https://github.com/missdora/Interactive-3D-Graphics-by-Udacity/issues/5","id":98616806,"number":5,"title":"Lesson 9: Shader Programming","user":{"login":"missdora","id":1185111,"avatar_url":"https://avatars.githubusercontent.com/u/1185111?v=3","gravatar_id":"","url":"https://api.github.com/users/missdora","html_url":"https://github.com/missdora","followers_url":"https://api.github.com/users/missdora/followers","following_url":"https://api.github.com/users/missdora/following{/other_user}","gists_url":"https://api.github.com/users/missdora/gists{/gist_id}","starred_url":"https://api.github.com/users/missdora/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/missdora/subscriptions","organizations_url":"https://api.github.com/users/missdora/orgs","repos_url":"https://api.github.com/users/missdora/repos","events_url":"https://api.github.com/users/missdora/events{/privacy}","received_events_url":"https://api.github.com/users/missdora/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":4,"created_at":"2015-08-02T15:28:18Z","updated_at":"2015-08-08T09:37:10Z","closed_at":null,"body":"Programmable Shaders\r\n\r\n![screen shot 2015-08-02 at 23 30 51](https://cloud.githubusercontent.com/assets/1185111/9026758/91d50d2a-396e-11e5-9c6f-06eacf2c5903.png)\r\n"},"comment":{"url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/comments/128944313","html_url":"https://github.com/missdora/Interactive-3D-Graphics-by-Udacity/issues/5#issuecomment-128944313","issue_url":"https://api.github.com/repos/missdora/Interactive-3D-Graphics-by-Udacity/issues/5","id":128944313,"user":{"login":"missdora","id":1185111,"avatar_url":"https://avatars.githubusercontent.com/u/1185111?v=3","gravatar_id":"","url":"https://api.github.com/users/missdora","html_url":"https://github.com/missdora","followers_url":"https://api.github.com/users/missdora/followers","following_url":"https://api.github.com/users/missdora/following{/other_user}","gists_url":"https://api.github.com/users/missdora/gists{/gist_id}","starred_url":"https://api.github.com/users/missdora/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/missdora/subscriptions","organizations_url":"https://api.github.com/users/missdora/orgs","repos_url":"https://api.github.com/users/missdora/repos","events_url":"https://api.github.com/users/missdora/events{/privacy}","received_events_url":"https://api.github.com/users/missdora/received_events","type":"User","site_admin":false},"created_at":"2015-08-08T09:37:10Z","updated_at":"2015-08-08T09:37:10Z","body":"[光照模型对比](http://blog.csdn.net/pizi0475/article/details/8035337)\r\n\r\nBlinn-Phong光照模型(修正镜面光)\r\n\r\nBlinn-Phong是一个基于Phong模型修正的模型，其公式为：\r\n\r\nIspec = Ks * Il * ( dot(N,H) )^Ns\r\n\r\n其中N是入射点的单位法向量，H是光入射方向L和视点方向V的中间向量，通常也称之为半角向量（半角向量被广泛用于各类光照模型，原因不但在于半角向量蕴含的信息价值，也在于半角向量是很简单的计算：H = (L + V) / |L + V|  ）。\r\nIl是点光源强度\r\nKs 为镜面反射系数\r\nNs是高光指数\r\n "}}