0 votes 0 votes Which of the following statements is/are True regarding the solution of the visibility problem in 3D graphics? S1: The painter's algorithm sorts polygons by depth and then paints (scan - converts) each Polygon on to the screen starting with the most nearest polygon S2: Backface Culling refers to eliminating geometry with backfacing normals S1 only S2 only Both S1 and S2 Neither S1 nor S2 Computer Graphics ugcnetcse-july2018-paper2 computer-graphics 3d-graphics + – Pooja Khatri asked Jul 13, 2018 • recategorized Oct 15, 2018 by Pooja Khatri Pooja Khatri 3.4k views answer comment Share Follow See all 3 Comments See all 3 3 Comments reply V Sharma commented Dec 12, 2018 reply Follow Share Corect ans is option (B), Can anyone explain it with reason/logic? Thanks!! 0 votes 0 votes yuviabhi commented Jun 20, 2019 reply Follow Share Question [IF YOU ARE UNABLE TO VIEW IT] Which of the following statements is/are True regarding the solution to the visibility problem in 3D graphics ? S1 : The Painter’s algorithm sorts polygons by depth and then paints (scan - converts) each Polygon on to the screen starting with the most nearest polygon. S2 : Backface Culling refers to eliminating geometry with backfacing normals. OPTIONS (1) S1 only (2) S2 only (3) Both S1 and S2 (4) Neither S1 nor S2 0 votes 0 votes Sanjay Sharma commented Aug 7, 2020 reply Follow Share option B is correct pls refer http://glasnost.itcarlow.ie/~powerk/GeneralGraphicsNotes/HSR/backfaceculling.html http://www.cs.umd.edu/~djacobs/CMSC427/VisibilityNonDiscrete.pdf 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes S1 is false, painter algorithm sorts polygons by depth, and then paints the farthest polygon first. S2 is true, backface curling don't render the curves, which are backface, and not visible. So, it enhances the rendering time. Option 2 Gaurav Parashar answered Jul 11, 2018 Gaurav Parashar comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes Option(3) Both S1 and S2. shahidhope answered Jul 14, 2018 shahidhope comment Share Follow See all 2 Comments See all 2 2 Comments reply yuviabhi commented Aug 29, 2018 reply Follow Share Pls explain since official key gives option (2) S2 only as correct answer. 0 votes 0 votes pansy_nandwani commented Oct 28, 2018 reply Follow Share I think option two will be right as painter algorithm paints polygon on screen starting with farthest polygon 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes (B) S2 only … For S1 Statement : The painter's algorithm, also known as a priority fill, is one of the simplest solutions to the visibility problem in 3D computer graphics. The name "painter's algorithm" refers to the technique employed by many painters for painting distant parts of a scene before parts which are nearer thereby covering some areas of distant parts. The painter's algorithm sorts all the polygons in a scene by their depth and then paints them in this order, farthest to closest. It will paint over the parts that are normally not visible which solving the visibility problem at the cost of having painted invisible areas of distant objects. So According To Above Paragraph The Option S1 Is False... For S2 Statement : Backface culling is an important part of how a 3D engine performs visibility checks. Its purpose is to detect polygons that are invisible in a particular scene that is, polygons that face away from the viewer. The process is similar to clipping, which determines if polygons are within the camera's field of view at all, and if not, are not rendered. Back-face culling is a method in computer graphics programming which determines whether a polygon of a graphical object is visible; if it is not, the polygon is "culled" from rendering process, which increases efficiency by reducing the number of polygons that the hardware has to draw. The vertices of front-facing polygons wind in a clockwise fashion, so polygons that face away from the camera are in a counter-clockwise order relative to the current view. When back-faces are culled, these polygons are not drawn. So According To Above Paragraph The Option S2 Is True... Awe111 answered Nov 16, 2021 Awe111 comment Share Follow See all 0 reply Please log in or register to add a comment.