State warnock algorithm, Data Structure & Algorithms

Assignment Help:

Warnock's Algorithm

An interesting approach to the hidden-surface problem was presented by Warnock. His method does not try to decide exactly what is happening in the scene but rather just tries to get the display right. As the resolution of the display increases, the amount of work which the algorithm must do to get the scene right also increases, (this is also true for scan-line algorithms). The algorithm divides the screen up into sample areas. In some sample areas it will be easy to decide what to do. If there are no faces within the area, then it is left blank. If the nearest polygon completely covers it, then it can be filled in with the colour of that polygon. If neither of these conditions holds, then the algorithm subdivides the sample area into smaller sample areas and considers each of them in turn. This process is repeated as needed. It stops when the sample area satisfies one of the two simple cases or when the sample area is only a single pixel (which can be given the colour of the foremost polygon). The process can also be allowed to continue to half or quarter pixel-sized sample areas, whose colour may be average over a pixel to provide antialiasing.  

The test for whether a polygon surrounds or is disjoint from the sample area is much like a clipping test to see if the polygon sides cross the sample-area boundaries. Actually the minimax test can be employed to identify many of the disjoint polygons. A simple test for whether a polygon is in front of another is a comparison of the z coordinates of the polygon planes at the corners of the sample area. At each subdivision, information learned in the previous test can be used to simplify the problem. Polygons which are disjoint from the tested sample area will also be disjoint from all of the sub-areas and do not need further testing. Likewise, a polygon which surrounds the sample area will also surround the sub-areas.

 


Related Discussions:- State warnock algorithm

Context sensitive f1 help on a field, In what ways we can get the context s...

In what ways we can get the context sensitive F1 help on a field?' Data element documentation. Data element additional text in screen painter. Using the process on help r

Perfect matching polytope ppm, Let G=(V,E) be a graph for which all nodes h...

Let G=(V,E) be a graph for which all nodes have degree 5 and where G is 5-edge is connected. a) Show that the vector x which is indexed by the edges E and for which xe = 1/5 for

Delete a given node from a doubly linked list, Algorithm to Delete a given ...

Algorithm to Delete a given node from a doubly linked list Delete a Node from Double Linked List DELETEDBL(INFO, FORW, BACK, START, AVAIL,LOC) 1. [Delete Node] Set FOR

Algorithm for determining strongly connected components, Algorithm for dete...

Algorithm for determining strongly connected components of a Graph: Strongly Connected Components (G) where d[u] = discovery time of the vertex u throughout DFS , f[u] = f

Algorithm, write an algorithm for the gpa of six students

write an algorithm for the gpa of six students

Binary tree creation, Binary tree creation struct NODE { struct N...

Binary tree creation struct NODE { struct NODE *left; int value; struct NODE *right; }; create_tree( struct NODE *curr, struct NODE *new ) { if(new->val

Explain what is stack. describe ways to execute stack. , ST AC K is ...

ST AC K is explained as follows : A stack is one of the most usually used data structure. A stack is also called a Last-In-First-Out (LIFO) system, is a linear list in

Total impedent of the circuit, an electrical student designed a circuit in...

an electrical student designed a circuit in which the impedence in one part of a series circuit is 2+j8 ohms and the impedent is another part of the circuit is 4-j60 ohm mm program

A linear list of elements in which deletion can be done, A linear list of e...

A linear list of elements in which deletion can be done from one end (front) and insertion can take place only at the other end (rear) is called as a   Queue.

Algorithm to sort a given list by quick sort method, Q. Write down an algor...

Q. Write down an algorithm to sort a given list by making use of Quick sort method. Describe the behaviour of Quick sort when input given to us is already sorted.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd