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

Proof of subsequent properties of bezier curves, Proof of subsequent proper...

Proof of subsequent properties of Bezier curves Note: Proof of subsequent properties of Bezier curves is left as a work out for the students P' (0) = n (p 1 - p 0 ) P

Explain briefly ancillary operations, Problem: a. Explain briefly six A...

Problem: a. Explain briefly six Ancillary Operations? b. When do ancillary operations take place? c. (i) What is flexography? (ii) Provide examples of finished produ

What are the features found in CAD, What are the features found in CAD ...

What are the features found in CAD Features generally found in a CAD package involve: - 2D and 3D modelling - Wire frame - Library of parts that can be used in new dra

Find out projection matrix for oblique projection, Find Out Projection Matr...

Find Out Projection Matrix for Oblique Projection To find out projection matrix for oblique projection, we want to find out the direction vector d. Because vector PP' and vect

Basic approaches for visible surface determination, Basic Approaches for Vi...

Basic Approaches for Visible Surface Determination There are two basic approaches for visible-surface determination, as per if they deal along with their projected images or a

Persistence of phosphor - display devices, Persistence (of phosphor) - Disp...

Persistence (of phosphor) - Display devices Time it takes the emitted light from screen to decay to one-tenth of its original intensity. The point where an electron gun strikes

Linearly interpolate - modeling and rendering, Linearly interpolate - Model...

Linearly interpolate - Modeling and Rendering I 4 = I 1 + t (I 2 - I 1 ); here t = (|y 1 - y 2 |)/(|y 1 - y 2 |) I D = I A + t (I B - I A ); here t = (|AD|)/(|AB|)

Determine the advantages of raster-scan systems, Determine the advantages o...

Determine the advantages of raster-scan systems (i)  Rasterisation is now performed faster since a special purpose processor is used. (ii)  The CPU is not slowed down by the

Interactive computer animation, Interactive Computer Animation Interac...

Interactive Computer Animation Interactive Computer Animation that is interactively utilized by users for example: games. Sprite animation is interactive and utilized broadly

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