Arrange the 2-D viewing transformation pipeline. A. Convert world-coordinates to viewing coordinates B. Map viewing coordinates to normalized viewing coordinates using window - viewpoint specifications C. Construct world - coordinates scene using modeling - coordinates transformations D. Map normalized viewpoint to device coordinates Choose the correct answer from the options given below:
C, A, B, D
The two-dimensional viewing pipeline (Hearn and Baker) carries a picture through a fixed chain of coordinate systems: modeling coordinates → world coordinates → viewing coordinates → normalized viewing coordinates → device coordinates.
Step 1 — C: each object is defined in its own modeling coordinates, and modeling transformations place the objects into a single world-coordinate scene.
Step 2 — A: the world-coordinate description is converted to viewing coordinates, which sets up the viewer position and orientation (the window is defined here).
Step 3 — B: the window-to-viewport specification maps viewing coordinates to normalized viewing coordinates in the unit square, where clipping is done independently of any device.
Step 4 — D: the normalized viewport is finally mapped to device coordinates of the actual output device.
So the order is C, A, B, D. The sequences D, C, B, A and D, C, A, B both begin with the device mapping D, which can only be the final step, and B, C, A, D normalizes viewing coordinates before the world scene is even built or converted to viewing coordinates; each contradicts the direction of the pipeline.
C, A, B, D option is correct.
Similar Questions
In Cyrus-Beck algorithm for line clipping the value of t parameter is computed by the relation :
(Here P1 and P2 are the two end points of the line, f is a point on the boundary, n1 is inner normal)
Which of the following statement(s) is/are incorrect ?
(a) Mapping the co-ordinates of the points and lines that form the picture into the appropriate co-ordinates on the device or workstation is known as viewing transformation.
(b) The right-handed cartesian co-ordinates system in whose co-ordinates we describe the picture is known as world co-ordinate system.
(c) The co-ordinate system that corresponds to the device or workstation where the image is to be displayed is known as physical device co-ordinate system.
(d) Left - handed co-ordinate system in which the display area of the virtual display device corresponds to the unit (|x|) square whose lower left-hand corner is at the origin of the co-ordinate system, is known as normalized device co-ordinate system.
Codes :
Consider a window bounded by the lines : x = 0; y= 0; x = 5 and y = 3. The line segment joining (-1, 0) and (4, 5), if clipped against this window will connect the points
Let R be the rectangular window against which the lines are to be clipped using 2D Sutherland-Cohen line clipping algorithm. The rectangular window has lower left-hand corner at (– 5, 1) and upper right-hand corner at (3, 7). Consider the following three lines for clipping with the given end point co-ordinates :
Line AB : A (– 6, 2) and B (–1, 8)
Line CD : C (– 1, 5) and D (4, 8)
Line EF : E (–2, 3) and F (1, 2)
Which of the following line(s) is/are candidate for clipping ?
Important Questions from Two Dimensional Viewing
- Which of the following technique is used for Clipping?
In Cyrus-Beck algorithm for line clipping the value of t parameter is computed by the relation :
(Here P1 and P2 are the two end points of the line, f is a point on the boundary, n1 is inner normal)
Rearrange steps involved in two dimensional viewing transformation.
I. Map normalized viewport to device Co-ordinates
II. Convert world co-ordinate to viewing co-ordinates
III. Construct world – co-ordinate scene using modeling coordinate transformation
IV. Map viewing co-ordinates to normalized viewing co-ordinates using window-viewportspecification
Which of the following statement(s) is/are incorrect ?
(a) Mapping the co-ordinates of the points and lines that form the picture into the appropriate co-ordinates on the device or workstation is known as viewing transformation.
(b) The right-handed cartesian co-ordinates system in whose co-ordinates we describe the picture is known as world co-ordinate system.
(c) The co-ordinate system that corresponds to the device or workstation where the image is to be displayed is known as physical device co-ordinate system.
(d) Left - handed co-ordinate system in which the display area of the virtual display device corresponds to the unit (|x|) square whose lower left-hand corner is at the origin of the co-ordinate system, is known as normalized device co-ordinate system.
Codes :
Consider a window bounded by the lines : x = 0; y= 0; x = 5 and y = 3. The line segment joining (-1, 0) and (4, 5), if clipped against this window will connect the points
