## 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.

#### Binary tree construction, Construct a B+ tree for the following keys, start...

Construct a B+ tree for the following keys, starting with an empty tree.  Each node in the tree can hold a maximum of 2 entries (i.e., order d = 1). Start with an empty root nod

#### Rooted tree, It does not have any cycles (circuits, or closed paths), which...

It does not have any cycles (circuits, or closed paths), which would imply the existence of more than one path among two nodes. It is the most general kind of tree, and might be co

#### Queue be represented by circular linked list, Q. Can a Queue be represented...

Q. Can a Queue be represented by circular linked list with only one pointer pointing to the tail of the queue? Substantiate your answer using an example. A n s . Yes a

#### State warnock algorithm, Warnock's Algorithm An interesting approach to...

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

#### Need it urgently, Write an assembly program to separate the number of posit...

Write an assembly program to separate the number of positive numbers and negative numbers from a given series of signed numbers.

#### Define a tree and list its properties, QUESTION (a) Define a tree and l...

QUESTION (a) Define a tree and list its properties. (b) By showing all your workings, draw the spanning tree for the following graph based on the Breadth-First-Search algori

#### Reverse order of elements on a slack, Q. Describe the representations of gr...

Q. Describe the representations of graph. Represent the graph which is given to us using any two methods Ans: The different ways by which we can represent graphs are:

#### In-order traversal, Write steps for algorithm for In-order Traversal Th...

Write steps for algorithm for In-order Traversal This process when implemented iteratively also needs a stack and a Boolean to prevent the execution from traversing any portion

#### Depth First Search Through Un-weighted Connected Graph , Q. Write down the ...

Q. Write down the algorithm which does depth first search through an un-weighted connected graph. In an un-weighted graph, would breadth first search or depth first search or neith

#### Explain the arrays in ruby, Explain the Arrays in Ruby Ruby arrays are ...

Explain the Arrays in Ruby Ruby arrays are dynamic arrays which expand automatically whenever a value is stored in a location beyond current end of the array. To the programmer  