2d Clipping Algorithm In Computer Graphics Research

qComputer Graphics have developed rapidly in the last years and are used in many field ,for example,CAD,TV advertisement and cartoon,etc.Computer Graphics . Have been a mature subject.Many basic algorithms of Computer Graphics have important function in the application.So it is very necessary to improre and perfect those algorithms. The next are the outcomes of studying the clipping algorithms. In chapter 1,The development of Computer Graphics is introduced ,as well as the difinition of clipping and basic algorithms,including point clipping,planar clipping and three-dimensional clipping. In chapter 2, puts forward a very effective clipping algorithm based on line's slope,and compares it with Cyrus-Berk Algorithm .The result indicates that it is simpler and more effective. In chapter 3, brings forward the necessary condition of intersecting of line and window boundraries firstly,based the coordinates of window vertexes and end-points of line .Eliminates efficiently the window boundraries that don'intersect with the line,and averts vast operations. In chapter 4, Translation and circumrotate are import firstly into the line clipping against circular window.Tht line is on x-coordinate and the left end–point is on coordinate origin.Transforms the local connection of line and circle into that of x-coordinate and circle.Simplify the calculation of intersection based on the eliminating the line that dosen't intersect with the circle. In chapter 4,gives a clipping algorithm fo elliptical window.It's judge whether there are intersections of line and ellipse by sum of distance from end points of line to two focus of ellipse and distance of the line and center of ellipse.