Chris Cai's Tech Blog

博客园 首页 新随笔 联系 订阅 管理

2009年11月14日 #

摘要: This small operation calcuates the distance between two points. The routine can work in any number of dimensions, so you cold apply it to 2D or 3D. In 2D Define your two points. Point 1 at (x1, y1) a... 阅读全文
posted @ 2009-11-14 12:06 Chris Cai 阅读(347) 评论(0) 推荐(0) 编辑

摘要: Separating axis theorem:http://en.wikipedia.org/wiki/Separating_axis_theoremPolygon Collision: http://gpwiki.org/index.php/Polygon_Collision 阅读全文
posted @ 2009-11-14 11:56 Chris Cai 阅读(192) 评论(0) 推荐(0) 编辑

摘要: Dot Prodcut The dot product (inner product) of two vectors is a measure of how similar the two vectors are (how much one is projected onto the other), multiplied by the magnitudes. Two vectors that ar... 阅读全文
posted @ 2009-11-14 11:53 Chris Cai 阅读(487) 评论(0) 推荐(0) 编辑

2009年11月3日 #

摘要: The concept of personalizing for customers is certainly not new. But the Web elevates it to a near art form. The Web is the perfect marketing environment for precision marketing, because individuals c... 阅读全文
posted @ 2009-11-03 08:52 Chris Cai 阅读(320) 评论(0) 推荐(0) 编辑