Phong shading algorithm, Computer Graphics

Assignment Help:

Q. Describe briefly phong shading algorithm.  

OR               

Write short note on phong shading.   

Phong shading   Phong shading or normal vector interpolation shading is an accurate method developed by phong Bui Tuong for rendering a polygon surface. It interpolates normal vectors and then apply the illumination model to each surface point. It displays more realistic highlights on a surface and greatly reduces the Match- band effect. A polygon surface is rendered using Phong shading by carrying out the following steps: 1. Determine the average unit normal vector at each polygon vertex. 2. Linearly interpolate the vertex normal over the surface of the polygon. 3. Apply an illumination model along each scan line to calculate project pixel intensities for the surface point. Phong shading method requires considerably more calculations. Surface rending with phong shading can be speed by up using approximations in the illumination model calculations of normal vectors. Fast phong shading approximates the intensity calculations using a Taylor- series expansion and triangular surface patches. Fast phong shading takes approximation twice as long as to render a surface then with Gouraud shading. Normal phong shading using forward difference takes about six to seven times longer then Gouraud shading. 

                                                                                                                                 

 


Related Discussions:- Phong shading algorithm

Image precision and object precision, Q.   What do you mean by image precis...

Q.   What do you mean by image precision and object precision? Describe z- buffer algorithm for visible surface detection. OR What do you mean by image precision and obj

Horizontal retrace - display devices, Horizontal retrace - Display Devices ...

Horizontal retrace - Display Devices In a refresh CRT monitor, the time it takes for an electron beam to return to the left most point on the next horizontal line after refresh

What is a dot size, What is a dot size? Dot size may be explained as th...

What is a dot size? Dot size may be explained as the diameter of a single dot on the devices output. Dot size is also known as the Spot size.

Explain difference between impact and non-impact printers, What is the diff...

What is the difference between impact and non-impact printers?  Impact printer press produced character faces against an inked ribbon on to the paper. A line printer and dot-ma

Ambient reflection-polygon rendering & ray tracing methods , Ambient Reflec...

Ambient Reflection-Polygon Rendering & Ray Tracing Methods When we go for the examiner of light effects, so surroundings play a significant role and it is assumed as there

What is a blobby object, What is a Blobby object?  Some objects do not ...

What is a Blobby object?  Some objects do not handle a fixed shape, but change their surface characteristics in sure motions or when in proximity to other objects. That is call

Design a game using graphical user interface, BlackJack is a popular card g...

BlackJack is a popular card game played in many casinos. The player plays against the dealer aiming to reach 21 points, or a score higher than the dealer without exceeding 21. The

Gourand shading, This renders a polygon surface by linearly interpolating i...

This renders a polygon surface by linearly interpolating intensity values across the surface. Intensity values for each polygon are matched with the values of adjacent polygon alon

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