Cohen sutherland line clippings algorithm, Computer Graphics

Cohen Sutherland Line Clippings Algorithm

The clipping problem is identified by dividing the region surrounding the window area into four segments Up as U, Down as D, Left as L, Right as R and assignment of number 1 and 0 to respective segments assists in positioning the area surrounding the window. How this positioning of areas is performed can be well determined by understood in following figure.

2465_Cohen Sutherland Line Clippings Algorithm.png

Figure: Positioning of regions surrounding the window

In figure as given above we have noticed that each coding of areas U, D, L and R is done along w.i.t. window region. Since window is neither Left nor Right, neither up nor down so, the respective bits UDLR are 0000; currently see area1 of above figure. The positioning code UDLR is 1010, that is the area1 lying on the position that is upper left side of the window. Hence, area1 has UDLR code 1010 i.e. Up so U=1, not Down so D=0, Left so L=1, not Right so R=0.

The sense of the UDLR code to identify the location of region w.i.t. window is:

1st bit ⇒ Up(U) ; 2nd bit ⇒ Down(D) ;3rd bit ⇒ Left(L) ;  4th bit ⇒ Right(R),

Currently, to perform Line clipping for different line segment that may reside within the window region partially or fully, or may not even lie in the widow area; we utilize the tool of logical ANDing among the UDLR codes of the points lying on the line.

Logical ANDing (^) operation


1 ^ 1 = 1; 1 ^ 0 = 0;

between respective bits implies




0 ^ 1 = 0; 0 ^ 0 = 0


  • UDLR code of window is 0000 all the time and with respect to this will generate bit codes of other areas.
  • A line segment is observable if both the UDLR codes of the end points of the line segment equal to 0000 that is UDLR code of window area. If the resulting code is not 0000 then, which line segment or section of line segment may or may not be observable
Posted Date: 4/3/2013 2:54:25 AM | Location : United States

Related Discussions:- Cohen sutherland line clippings algorithm, Assignment Help, Ask Question on Cohen sutherland line clippings algorithm, Get Answer, Expert's Help, Cohen sutherland line clippings algorithm Discussions

Write discussion on Cohen sutherland line clippings algorithm
Your posts are moderated
Related Questions
Three Sub-Fields of Computer Simulation Computer simulation is the electronic equivalent of this kind of role playing and it functions to drive synthetic environments and virt

Define  Aspect ratio- Aspect ratio: The ratio of vertical points to horizontal points necessary to produce equal –length lines in both directions on the screen, is called as

State the Areas of use of data goggles Entertainment   Used in television/films as special effects (for example "holodeck" in Star Trek: The Next Generation and Brazilian

Types of Polygon tables curves and surfaces Attribute tables: This table has object information as transparency, surface reflexivity, texture features of an object in the vi

Different types of Simulating Motion - Computer Animation Here we discuss different ways of simulating motion as: a. Zero Acceleration or Constant Speed b. No

Art: it just like conventional animation, computer animation is additionally a type of art. A multitude of results can be created on a computer than on a piece of paper. An artist

Achieve a perspective projection on the z = 0 plane of the unit cube, demonstrated in Figure (l) from the cop at E (0, 0, 10) upon the z-axis. Figure: I 01:  currently c

Question 1 Write a note on digitizers Question 2 Discuss on line drawing algorithm Question 3 Explain 3D viewing Question 4 Explain different types of cohe