Gourand shading, Computer Graphics

Assignment Help:

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 along the common edges, thus eliminating the intensity discontinuities that can occur in flat shading. Each polygon surface is rendered with Gourand shading by performing the following calculation:  (i) Determine the average unit normal vector at each polygon vertex. (ii) Apply an illumination model to each vertex to calculate the vertex intensity. (iii) Linearly interpolate the vertex intensities over the surface of the polygon. At each polygon vertex we obtain a normal vector by averaging the surface normal of all polygons sharing that vertex. Thus for vertex position V, we obtain the unit vertex normal width the calculation. One we have the vertex normal's, we determine the intensity at the vertices from a lightning model. Incremental calculations are used to obtain successive edge intensity values between scan lines and to obtain successive intensities along a scan line. 

 

 


Related Discussions:- Gourand shading

Derive the single combined transformation matrix, A 2D geometric shape is r...

A 2D geometric shape is rotated about a point with coordinates (1,2)  by 90°  in a clockwise direction.  Then, the shape is scaled about the same point in the x-coordinate by 2 tim

What makes a pattern a pattern, QUESTION (a) Suppose that you have been...

QUESTION (a) Suppose that you have been assigned to re-engineer the existing systems for a company. Do you think that design patterns can be applied to these existing systems?

Two-dimensional geometric transformations, Two-Dimensional Geometric Transf...

Two-Dimensional Geometric Transformations  When a real life object is modelled using shape primitives, there are several possible applications.  You may be required to do furth

Illustration of a clipping window - raster graphics, Illustration of a Clip...

Illustration of a Clipping window ABCD is placed as follows: A (100, 10), B (160, 10, C (160, 40), D (100, 40) By using Sutherland-Cohen clipping algorithm determine the vis

Disadvantages of the z-buffer method, Disadvantages : 1)   Doubles memor...

Disadvantages : 1)   Doubles memory needs, one for at least z-buffer and one for refreshes- buffer. 2)   Dependency of device and memory intensive. 3) Wasted calculation u

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

Differentiate images and graphics, Question 1 Discuss the general properti...

Question 1 Discuss the general properties of analog signal Question 2 Differentiate images and graphics Question 3 Explain the video compression standard H.263

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