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

What is persistence and resolution, What is persistence and resolution?  ...

What is persistence and resolution?  The time it takes the emitted light from the screen to decay one tenth of its original intensity is known as a persistence.  The maximum

Ellipse generation algorithm - 2d shape primitives, Ellipse Generation Algo...

Ellipse Generation Algorithm  You know that a circle is symmetric in all the octants, while ellipse is symmetric with respect to four quadrants.  Therefore, to draw an ellipse,

Word perfect graphic, WPG: It is word perfect graphic file that is used vi...

WPG: It is word perfect graphic file that is used via Word Perfect. It first came out with the release of word perfect 5.0. Such files can include bitmaps, line arts and vector gr

Construction of an isometric projection - transformation, Construction of a...

Construction of an Isometric Projection - Transformation In this projection, the direction of projection i.e. d = (d 1 ,d 2 ,d 3 ) makes an identical angles with all the 3-pr

Scaling, uniform scaling and differential scaling with the help of diagram

uniform scaling and differential scaling with the help of diagram

Painting and drawing, Painting and Drawing While we talk about graphic...

Painting and Drawing While we talk about graphics, we mean pictures can be either photographs or illustrations. If you want to acquire graphics into a Web page or multimedia r

Define b-spline curve, Define B-Spline curve?  A B-Spline curve is a se...

Define B-Spline curve?  A B-Spline curve is a set of piecewise (usually cubic) polynomial segments that pass close to a set of control points. Though the curve does not pass by

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