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

Do we have need of to generate full circumference of circle, 1.   Do we hav...

1.   Do we have need of to generate the full circumference of the circle utilizing the algorithm or  can we can produces it in a quadrant or octant only and after that utilization

Bezier cubic curves, Q.   What are Bezier cubic curves? Derive their proper...

Q.   What are Bezier cubic curves? Derive their properties. OR  What are Bezier cubic curves? Derive these properties. Also show that the sum of the blending functions is identical

What is the need of homogeneous coordinates, What is the need of homogeneou...

What is the need of homogeneous coordinates?  To perform more than one transformation at a time, use homogeneous coordinates or matrixes. They decrease unwanted calculations in

Digital audio comprises audio signals, Digital audio comprises audio signal...

Digital audio comprises audio signals stored in a digital format. Particularly, the term encompasses the subsequent: 1)   Audio conversion: 1.   Analogue to digital conversi

Light pen - input and output devices, Light Pen - input and output devices ...

Light Pen - input and output devices It is a pointing device. This has a light sensitive tip that is excited while the light is emitted and an illuminated point upon the disp

Vector graphics, Vector Graphics: These are images which may be entirely d...

Vector Graphics: These are images which may be entirely described by using mathematical definitions. The image below demonstrates the principle. To the left you notice the image i

Midpoint circle generation algorithm - 2d shape primitives, Midpoint Circle...

Midpoint Circle Generation Algorithm   Just as a line drawing algorithm approximates infinite number of points on a line segment by only a finite number of pixels, a circle dra

What are the different ways of specifying spline curve, What are the differ...

What are the different ways of specifying spline curve?  Using a set of boundary conditions that are imposed on the spline. Using the state matrix that characteristics

Interpolation of surface - polygon rendering, Interpolation of surface - Po...

Interpolation of surface - Polygon Rendering Interpolation of surface normals beside the polygonedge between two vertices is demonstrated above in the figure 15. Here the norm

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