2 types of line clipping algorithm with example. Cohen-Sutherland Line Clipping and Liang-Barsky Line Clipping Algorithm By Shilpa. Liang-Barsky line clipping algorithm. ▫ Sutherland-Hogeman polygon clipping. 3. Pedher Johansson. Department of Computing Science, Umeå University. Liang – Barsky line clipping algorithm is faster line clipper algorithm based on analysis of the parametric equation of a line segment. Parametric equation of line .
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It basically avoids any unnecessary calculations if the line was already completely inside the edges to start with: We need to find out some values before we proceed.
In the Liang-Barsky approach we first the point clipping condition in parametric form: If P is more than zero however which it isn’t clippibg this example btw – we’ve already had the above executed, so the below algogithm is only for future edge checks!
Since we don’t have LaTeX markup in this exchange, I’ll use bold to represent n-dimensional vectors. If there is a segment of line inside the liabg region, a sequence of infinite line intersections must go entering, entering, exiting, and exiting as shown in figure Linf up or log in Sign up using Google. Engineering in your lie Download our mobile app and study on-the-go. It was created after I went through torture trying to research it myself for my uni course.
Liang — Barsky line clipping algorithm is faster line clipper algorithm based on analysis of the parametric equation of a line segment. Also remember to take the new values for t0 and t1 into account the instructions above assume we’re starting out, and therefore think that t0 still equals 0 and t1 still equals 1, when that’ll change as we check each edge in turn. Amount you wish to contribute: Email Required, but never shown.
Liang-Barsky Line Clipping Algorithm – Stack Overflow
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We use slightly different values for P and Q R remains the same though: Therefore we ignore it. Post as a guest Name. You get question papers, syllabus, subject analysis, answers – all in one app.
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Parametric equation of line segment: We can store these values in variables, as we will oiang to adjust them as the algorithm progresses. What we’ll do is go through each edge border in turn Left, Right, Bottom, Topand at each stage we will either tweak t0 or t1, or we may find out that the line is outside the border completely, and therefore doesn’t need drawing – in which case we will cut the algorithm there and then!
Now go to next edge. Sign up using Facebook. Diagram 1 GOAL – Clip line to the inside of the lighter blue area To begin with, we assume that we want to draw the whole line. Diagram 1b Left edge check: The Liang-Barsky line clipping algorithm in a nutshell! Maybe try out Computer Graphics Stack Exchange computergraphics. Sign up using Email and Password.