Handle By, S.JENILA AP/IT CS2401 COMPUTER GRAPHICS Handle By, S.JENILA AP/IT

AIM To learn the concepts of computer graphics, object transformations, 3D concepts & graphics programming. OBJECTIVE To introduce the basic concepts of primitives and two-dimensional concepts. To study the three-dimensional concepts, object representations. To learn color models & graphics programming using OPENGL. To understand rendering & shading of objects. To learn fractals, ray tracing & surface texture of objects.

SYLLABUS UNIT I 2D PRIMITIVES 9 Output primitives – Line, Circle and Ellipse drawing algorithms - Attributes of output primitives – Two dimensional Geometric transformation - Two dimensional viewing – Line, Polygon, Curve and Text clipping algorithms UNIT II 3D CONCEPTS 9 Parallel and Perspective projections - Three dimensional object representation – Polygons, Curved lines, Splines, Quadric Surfaces,- Visualization of data sets - 3D transformations – Viewing -Visible surface identification. UNIT III GRAPHICS PROGRAMMING 9 Color Models – RGB, YIQ, CMY, HSV – Animations – General Computer Animation, Raster, Keyframe - Graphics programming using OPENGL – Basic graphics primitives – Drawing three dimensional objects - Drawing three dimensional scenes

SYLLABUS UNIT IV RENDERING 9 Introduction to Shading models – Flat and Smooth shading – Adding texture to faces – Adding shadows of objects – Building a camera in a program – Creating shaded objects – Rendering texture – Drawing Shadows. UNIT V FRACTALS 9 Fractals and Self similarity – Peano curves – Creating image by iterated functions – Mandelbrot sets – Julia Sets – Random Fractals – Overview of Ray Tracing – Intersecting rays with other primitives – Adding Surface texture – Reflections and Transparency – Boolean operations on Objects TOTAL :45 PERIODS

 Line, circle and ellipse drawing algorithms UNIT I - 2D PRIMITIVES  Line, circle and ellipse drawing algorithms DDA Algorithm (Digital Differential Analyzer) Bresenham’s line, circle & ellipse algorithm

Two Dimensional geometric transformations Rotation Translation Shearing Scaling

UNIT II 3D CONCEPTS Three-Dimensional object representations Three-Dimensional geometric and modeling transformations Three-Dimensional viewing Hidden surface elimination Color models Animation.

parallel & perspective projection For parallel projections, we specify a direction of projection (DOP) instead of a COP. A perspective projection can be set up by specifying the position and size of the view plane and the position of the projection reference point.

Splines A spline is a smooth curve defined mathematically using a set of constraints Splines have many uses: 2D illustration Fonts 3D Modelling Animation

Three-Dimensional Display Methods Depth Cueing To easily identify the front and back of display objects. The intensity of objects according to the distance of viewing position Surface rendering Set the surface intensity of objects according to Lighting conditions in the scene Assigned surface characteristics

Visible Surface Detection (identification) Depth-Buffer (Z-Buffer) Each z-buffer location - Max z value Each frame buffer location - background color Scan Line Method Intersect each polygon with a particular scanline and solve hidden surface problem for just that scan line Octrees Visible-surface identification is accomplished by searching octree nodes in a front-to-back order

UNIT III - GRAPHICS PROGRAMMING Color Models All colors are generated from the three primaries various colors are obtained by changing the amount of each primary RGB model CMY model

3-D model of a jack inside a cube, and the jack alone below ANIMATION 3-D model of a jack inside a cube, and the jack alone below

Keyframe Animation 1’ 1 3’ 3 added point 2’ 2 Key frame k+1 Halfway frame 3 3’ added point

UNIT IV RENDERING Shading Shading Techniques Flat Gouraud Phong

Morphing Morphing – derived from the word metamorphosis. Metamorphosis means to change shape, appearance or form.

Rendering Texture Comparing the images with specular highlights, shadows, textures

Self similarity between parts and overall features of the object Unit – V Fractals Fractals Self similarity between parts and overall features of the object Koch Curve Hilbert curve Peano curve

Mandelbrot & JULIA set The Julia set can be computed by iteration similar to the Mandelbrot computation. The only difference is that the c value is fixed and the initial z value varies. The Mandelbrot set is the set of all complex c such that iterating Mandelbrot Set Julia Set

Reflection and Transparency Ray Tracing Techniques Ray Tracing Reflection and Transparency

TEXT BOOKS Donald Hearn, Pauline Baker, Computer Graphics – C Version, second edition, Pearson Education,2004. F.S. Hill, Computer Graphics using OPENGL, Second edition, Pearson Education,200UNIT III   REFERENCES James D. Foley, Andries Van Dam, Steven K. Feiner, John F. Hughes, Computer Graphics- Principles and practice, Second Edition in C, Pearson Education, 2007.

Assignment Topics Ellipse drawing algorithm Splines Color models Shading Random fractals

Seminar Topics 2D viewing Visible surface identification Animations Adding texture to faces Ray Tracing