Introduction to computer graphics
- 1. Prof.Sonal Badhe 1 COMPUTER GRAPHICS Prof. Sonal Badhe
- 2. Computer Graphics (CG) IA Test1 20 IA Test2 20 Average 20 End Sem Exam 80 Computer Graphics Laboratory (CGL) Term work 25 Oral & Practical 25 Prof.Sonal Badhe 2
- 3. Computer Graphics (CG) 3Prof.Sonal Badhe
- 4. SYLLABUS 1 Introduction and Overview of Graphics System 2 Output Primitives 3 Two Dimensional Geometric Transformations 4 Two Dimensional Viewing and Clipping 5 Three Dimensional Object Representations, Geometric Transformations and 3D Viewing 6 Visible Surface Detection 7 Illumination Models and Surface Rendering Prof.Sonal Badhe 4
- 5. 5 Text Books: 1. “Computer Graphics” C version by Hearn & Baker, 2nd Edition, Pearson 2. “Computer Graphics Principles and Practice in C , 2nd Edition ,James D. Foley, Andries van Dam, Steven K Feiner, John F. Hughes, Pearson . 3. “Computer Graphics”, by Rajesh K. Maurya, Wiley India Publication. 4. “Computer Graphics “ , by Samit Bhattacharya , Oxford Publication. Prof.Sonal Badhe
- 6. Computer Graphics Lab (CGL) 6Prof.Sonal Badhe
- 7. 7 List of Desirable Experiments: 1. Study and apply basic opengl functions to draw basic primitives. (*) 2. Implement sierpinsky gasket using openGL. 3. Implement DDA Line Drawing algorithms and Bresenham algorithm(*) 4. Implement midpoint Circle algorithm(*) 5. Implement midpoint Ellipse algorithm 6. Implemen tArea Filling Algorithm: Boundary Fill, Flood Fill ,Scan line Polygon Fill (*) 7. Implement Curve : Bezier for n control points , B Spline (Uniform ) ( atleast one)(*) 8. Implement Fractal (Koch Curve) 9. Character Generation : Bit Map method and Stroke Method 10. Implement 2D Transformations: Translation, Scaling, Rotation, Reflection, Shear.(*) 11. Implement Line Clipping Algorithm: Cohen Sutherland / Liang Barsky.(*) 12. Implement polygon clipping algorithm(atleast one) 13. Program to represent a 3D object using polygon surfaces and then perform 3D transformation. 14. Program to perform projection of a 3D object on Projection Plane : Parallel and Perspective.(*) Prof.Sonal Badhe
- 8. 8 Term Work 1. Term work should consist of at least 12 experiments. (*) Practical to be covered necessarily 2. Journal must include at least 2 assignments. 3. Mini Project to perform using C / OpenGL. Possible Ideas: a. Animation using multiple object b. Graphics editor with following features : *Draw basic geometrical entities; apply geometrical transformations, Area filling, Clipping against Clip window, displaying the text, displaying bar / line graphs , pie charts etc. Prof.Sonal Badhe
- 9. 9 Term Work: 25 Marks (Total) = 10 Marks (Experiments) + 5 Marks (Mini Project) + 5 Marks (Assignments) + 5 Marks (Theory + Practical Attendance) Oral & Practical exam will be based on the practical list and syllabus of Computer Graphics Prof.Sonal Badhe
- 10. Prof.Sonal Badhe 10 COMPUTER GRAPHICS Chapter 1: Introduction and overview of graphics system Still from Pixar’s Inside Out, 2015
- 11. 11 Chapter/Module-1 Introduction and Overview of Graphics System: • Definition And Representative Uses Of Computer Graphics, •Classification Of Application Areas • Overview Of Coordinate Systems •Definition Of Scan Conversion • Rasterization And Rendering • Raster Scan & Random Scan Displays •Flat Panel Displays Like Lcd And Led •Architecture Of Raster Graphics System With Display Processor • Architecture Of Random Scan Systems Prof.Sonal Badhe
- 12. • Computer graphics generally means creation, storage and manipulation of models and images • Such models come from diverse and expanding set of fields including physical, biological, mathematical, artistic, and conceptual/abstract structures What is Computer Graphics? Prof.Sonal Badhe 12
- 13. What is Computer Graphics? • Imaging – Representing 2D images • Modeling – Representing 3D objects • Rendering – Constructing 2D images from 3D models • Animation – Simulating changes over time Prof.Sonal Badhe 13
- 15. 1. COMPUTER AIDED DESIGN (CAD) • Used in design of buildings, automobiles, aircraft, watercraft, spacecraft, computers, textiles & many other products • Objects are displayed in wire frame outline form • Software packages provide multi-window environment Prof.Sonal Badhe 15
- 17. • Graphics design package provides standard shapes (useful for repeated placements) • Animations are also used in CAD applications • Realistic displays of architectural design permits simulated “walk” through the rooms (virtual - reality systems) Prof.Sonal Badhe 17
- 21. Prof.Sonal Badhe 21 Multiple window environment Enlarged sections/different view of environment
- 22. 2. PRESENTATION GRAPHICS • Used to produce illustrations for reports or generate slides for use with projectors • Commonly used to summarize financial, statistical, mathematical, scientific, economic data for research reports, managerial reports & customer information bulletins • Examples : Bar charts, line graphs, pie charts, surface graphs, time chartProf.Sonal Badhe 22
- 23. EXAMPLES OF PRESENTATION GRAPHICS Prof.Sonal Badhe 23
- 24. EXAMPLES OF PRESENTATION GRAPHICS Prof.Sonal Badhe 24
- 25. Presentation Graphics/Desktop Publishing Prof.Sonal Badhe 25
- 26. 3. COMPUTER ART • Used in fine art & commercial art • Includes artist’s paintbrush programs, paint packages, CAD packages and animation packages • These packages provides facilities for designing object shapes & specifying object motions. • Examples : Cartoon drawing, paintings, poduct advertisements, logo designProf.Sonal Badhe 26
- 28. • Painting packages are available. With cordless, pressure sensitive stylus, artists can produce electronic paintings which simulate different brush strokes, brush widths, and colors. • Photorealistic techniques, morphing and animations ar very useful in commercial art. • For films, 24 frames per second are required. For video monitor, 30 frames per second are required.Prof.Sonal Badhe 28
- 29. 29 The Cave Automatic Virtual Environment at EVL, University of Illinois at ChicagoProf.Sonal Badhe
- 32. 4. ENTERTAINMENT Movie Industry Used in motion pictures, music videos, and television shows. Used in making of cartoon animation films Prof.Sonal Badhe 32
- 38. Game Industry Focus on interactivity Cost effective solutions Avoiding computations Prof.Sonal Badhe 38
- 39. 5. EDUCATION & TRAINING • Computer generated models of physical, financial and economic systems are used as educational aids. • Models of physical systems, physiological systems, population trends, or equipment such as color- coded diagram help trainees understand the operation of the system Prof.Sonal Badhe 39
- 41. Specialized systems used for training applications simulators for practice sessions or training of ship captains aircraft pilots heavy equipment operators air traffic-control personnel Prof.Sonal Badhe 41
- 48. 6. VISUALIZATION• Scientific Visualization • Producing graphical representations for scientific, engineering, and medical data sets Visualization of how a car deforms in an asymmetrical crash Prof.Sonal Badhe 48
- 49. A scientific visualization of a simulation of instability caused by two mixing fluids Prof.Sonal Badhe 49
- 50. Airflow around a Harrier Jet (NASA Ames) Prof.Sonal Badhe 50
- 51. • Business Visualization is used in connection with data sets related to commerce, industry and other non-scientific areas • Techniques used- color coding, contour plots, graphs, charts, surface renderings & visualizations of volume interiors. • Image processing techniques are combined with computer graphics to produce many of the data visualizations Prof.Sonal Badhe 51
- 52. 7. IMAGE PROCESSING • CG- Computer is used to create a picture • Image Processing – applies techniques to modify or interpret existing pictures such as photographs and TV scans • Medical applications • Picture enhancements • Tomography • Simulations of operations • Ultrasonics & nuclear medicine scanners • 2 applications of image processing • Improving picture quality • Machine perception of visual information (Robotics)Prof.Sonal Badhe 52
- 56. 8. GRAPHICAL USER INTERFACES • Major component – Window manager (multiple-window areas) • To make a particular window active, click in that window (using an interactive pointing device) • Interfaces display – menus & icons • Icons – graphical symbol designed to look like the processing option it represents • Advantages of icons – less screen space, easily understood • Menus contain lists of textual descriptions & iconsProf.Sonal Badhe 56
- 61. Prof.Sonal Badhe 61 INPUT DEVICES
- 62. Prof.Sonal Badhe 62 INTRODUCTION • An input device is a piece of hardware by which a user enters information into computer system. • Example: mouse, trackball, joystick, voice systems, touch screens,etc. • A major goal in designing graphics packages is device independence enhances portability of the application
- 64. Prof.Sonal Badhe 64 • An alphanumeric keyboard is used primarily as a device for entering text strings. • The keyboard is an efficient device for inputting such nongraphic data as picture labels associated with graphics display. • Cursor control keys and function keys are common features on general purpose keyboards. • These days, keyboard has a good ergonomic design ; it has a detachable palm rest, slope adjustments, split keys for natural hand • Two types ,which are the fix-split key board and the adjustable split keyboard. The adjustable split keyboard consist of several pieces which angles can be change according to the user's preference.
- 66. Prof.Sonal Badhe 66 • A mouse is a small hand-held BOX used to position the screen cursor. • Wheels or Rollers(now-a-days Laser lights) on the bottom are used to record the position of the screen. • Generally there are two or three buttons, used for operations like recording of the cursor positions or invoking of a function. • In order to increase the number of INPUT parameters, additional devices can be included. • The Z-MOUSE is an example of this.
- 68. Prof.Sonal Badhe 68 Z- MOUSEKEY FEATURES: • Has three buttons, a thumbwheel on the side, a trackball on the top and a standard mouse ball underneath • With Z mouse, we can pick up an object,rotate it, and move it in any direction etc. • Allow 3D viewing. • Applications include virtual reality,CAD, and animation.
- 69. TRACKBALL & SPACEBALL Trackball Spaceball Prof.Sonal Badhe 69
- 70. TRACKBALL • It is a 2D positioning device. • It consists a ball held by a socket containing sensors to detect the rotation of ball about TWO axis. • User rolls the ball to move the cursor. • They are often mounted on devices such as keyboards, Z-mouse etc. SPACEBALL • It provides SIX degrees of freedom. • It is a fix device. • Movement detection is done using strain gauges. • Cursor can move in any direction. • It is more efficient then trackball.Prof.Sonal Badhe 70
- 71. Prof.Sonal Badhe 71 APPLICATIONS Used in CAD workstations In animation Sometimes on special Workstations such as the radar consoles in air-traffic control room In Gaming consoles People with a mobility impairment use trackballs as an assistive technology input device
- 73. KEY FEATURES: • Consists of a stick pivoted on a base. • Used to steer the screen cursor. • It also has one or two PUSH Buttons as input switches to perform certain actions. • Most joystick are 2D, but 3D do exist. • Distance moved from the CENTER position corresponds to the screen cursor movement in that direction. Prof.Sonal Badhe 73
- 74. Prof.Sonal Badhe 74 APPLICATIONS • In Gaming consoles • In 3D animation • Used to drive machines like cranes, mining trucks, hydraulics etc. • Used as assistive technology pointing device such as in Electronic wheelchairs
- 75. Prof.Sonal Badhe 75 DATA GLOVE
- 76. Prof.Sonal Badhe 76 KEY FEATURES: • Used to grasp a “virtual” object. • Uses sensors to detect the Hand and finger motion. • Electromagnetic coupling between signals provides information about the position and orientation of the hand.
- 77. Prof.Sonal Badhe APPLICATIONS • In 3D animation movies • Visual effects • Gestures can be categorized into useful information,such as to recognize Sign Language or other symbolic functions • 3D Virtual environment Games 77
- 79. KEY FEATURES: • Common device for drawing, painting,or interactively selecting coordinate positions on an object • Typically, it is used to scan an Object and to input discrete coordinate positions • ONE TYPE of Digitizer is the Graphics Tablet • It converts graphics and pictorial data into binary inputs. A graphic tablet as digitizer is used for doing fine works of drawing and images manipulation applications. Prof.Sonal Badhe 79
- 80. Prof.Sonal Badhe 80 APPLICATIONS • Used in generating Computer generated graphic images • Used in creating characters for Animation • In Technical drawings and CAD • Used for Handwriting recognition
- 81. Prof.Sonal Badhe 81 Image scanners
- 82. Prof.Sonal Badhe KEY FEATURES: • In computing, a scanner is a device that optically scans images, printed text, handwriting,or an object, and converts it to a digital image. • When the scanning is performed, the gradation of gray scale or colors are recorded and stored in an array. • Once scanned, any kind of transformations can be applied to the object image. 82
- 86. 86 Beam Penetration CRT Prof.Sonal Badhe
- 99. Raster scan Display Prof.Sonal Badhe 99
- 100. 100 Architecture of raster scan display Prof.Sonal Badhe
- 101. Random scan Display Prof.Sonal Badhe 101
- 102. 102 Architecture of random scan display Prof.Sonal Badhe
- 103. Prof.Sonal Badhe 103 Raster Scan System Random Scan System Resolution It has poor or less Resolution because picture definition is stored as a intensity value. It has High Resolution because it stores picture definition as a set of line commands. Electron- Beam Electron Beam is directed from top to bottom and one row at a time on screen, but electron beam is directed to whole screen. Electron Beam is directed to only that part of screen where picture is required to be drawn, one line at a time so also called Vector Display. Cost It is less expensive than Random Scan System. It is Costlier than Raster Scan System. Refresh Rate Refresh rate is 60 to 80 frame per second. Refresh Rate depends on the number of lines to be displayed i.e 30 to 60 times per second.
- 104. 104 Picture Definition It Stores picture definition in Refresh Buffer also called Frame Buffer. It Stores picture definition as a set of line commands called Refresh Display File. Line Drawing Zig – Zag line is produced because plotted value are discrete. Smooth line is produced because directly the line path is followed by electron beam . Realism in display It contains shadow, advance shading and hidden surface technique so gives therealistic display of scenes. It does not contain shadow and hidden surface technique so it can not give realistic display of scenes. Image Drawing It uses Pixels along scan lines for drawing an image. It is designed for line drawing applications and uses various mathematical function to draw. Prof.Sonal Badhe
- 105. 105 Chapter/Module-1 Introduction and Overview of Graphics System: • Definition And Representative Uses Of Computer Graphics, •Classification Of Application Areas • Overview Of Coordinate Systems •Definition Of Scan Conversion • Rasterization And Rendering • Raster Scan & Random Scan Displays •Flat Panel Displays Like Lcd And Led •Architecture Of Raster Graphics System With Display Processor • Architecture Of Random Scan Systems Prof.Sonal Badhe
- 106. 106 Questions 1) What is computer Graphics? Explain various application of computer graphics 2) List and explain various input and output devices 3) Explain Raster and Random scan display 4) Differentiate between raster and Random Scan Display 5) Explain architecture of Random Scan and Random Scan Display. Prof.Sonal Badhe
- 108. 108 Exercise Que: Identify the application areas for listed computer graphics applications. Prof.Sonal Badhe
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- 134. Making Movies Prof.Sonal Badhe 134
- 135. 135 Making Movies • Concept • Storyboarding • Sound • Character Development • Layout and look • Effects • Animation • Lighting Prof.Sonal Badhe
- 136. 136 Concept • “Nothing gets in the way of the story” –John Lasseter (Pixar) Prof.Sonal Badhe
- 137. Story-boarding• Explicitly define – Scenes – Camera shots – Special effects – Lighting – Scale • Used as guide by animators 137Prof.Sonal Badhe
- 138. 138 Sound • Voice recording of talent completed before animation begins • Animations must match the voice over • A puppeteer once told me that the voice makes or breaks a character Prof.Sonal Badhe
- 139. 139 Character Development • 300 Drawings Prof.Sonal Badhe
- 140. 140 Character Development • 40 Sculptures Prof.Sonal Badhe
- 142. 142 Layout & Look • Build scenery • Match colors Prof.Sonal Badhe
- 143. 143 Matchmoving • CG camera must exactly match the real camera –Position –Rotation –Focal length –Aperature • Easy when camera is instrumented • Hard to place CG on moving objects on filmProf.Sonal Badhe
- 145. 145 Matchmoving • Known patterns in live action made it easier to track – furniture, wall paper • 2D – 3D conversion in Maya Prof.Sonal Badhe
- 146. 146 Shooting Film For CG • Actors practice with small scale models • Maquettes replaced with laser dots – lasers on when camera shutter is closed • After each take, three extra shots – chrome ball for environment map for Stuart’s eyes – white and gray balls for lighting info Prof.Sonal Badhe
- 147. 147 Matchmoving • Film scanned • Camera tracking data retrieved • 3D Equalizer + Alias Maya to prepare (register) the digital camera • Once shot is prepared, 2D images rendered and composited with live action Prof.Sonal Badhe
- 157. 157 Buttons and Creases Prof.Sonal Badhe
- 159. 159 Companies • Pixar • Disney • Sony Imageworks • Industrial Light and Magic (ILM) • Rhythm and Hues • Pacific Data Images (PDI) • Dreamworks SKG • Tippett Studios • Angel Studios • Blue Sky • Robert Abel and Associates • Giant Studios Prof.Sonal Badhe
- 160. 160 Toy Story (1995) • 77 minutes long; 110,064 frames • 800,000 machine hours (91 years!) of rendering • 1 terabyte of disk space • 3.5 minutes of animation produced each week (maximum) • Frame render times: 45 min – 20 hours • 110 Suns operating 24-7 for rendering – 300 CPU’s Prof.Sonal Badhe
- 161. 161 Toy Story • Texture maps on Buzz: 189 – (450 to show scuffs and dirt) • Number of animation ‘knobs’ – Buzz – 700 – Woody – 712 • Face – 212 • Mouth – 58 – Sid’s Backpack – 128 • Number of leaves on trees – 1.2 mil • Number of shaders – 1300 • Number of storyboards – 25,000Prof.Sonal Badhe
- 162. 162 Toy Story 2 • 80 minutes long, 122,699 frames • 1400 processor render farm • Render time of 10 min to 3 days • Direct to video film • Software tools – Alias|Wavefront – Amazon Paint – RenderMan Prof.Sonal Badhe
- 163. 163 Newman! • Subdivision-surfaces • Polygonal hair (head) – Texture mapped on arms • Sculpted clothes • Complex shaders Prof.Sonal Badhe
- 164. 164 Devil’s in the Details • Render in color • Convert to NTSC B/W • Add film effects – Jitter – Negative scratches – Hair – Static Prof.Sonal Badhe
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- 168. 168 Stuart Little • 500 shots with digital character • 6 main challenges – Lip sync – Match-move (CG to live-action) – Fur – Clothes – Animation tools – Rendering, lighting, compositing Prof.Sonal Badhe
- 169. 169 Stuart Little • 100+ people worked on CG – 32 color/lighting/composite artists – 12 technical assistants – 30 animators – 40 artists – 12 R&D Prof.Sonal Badhe
- 172. 172 Final Fantasy • First ever animated feature to attempt photorealistic CGI humans • Second biggest box office flop ever (lost over $124M) • Main characters > 300,000 polys • 1336 shots • 24,606 layers • 3,000,000 renders (if only rendered once) – typically 5 render revisions – render time per frame = 90 min • Most layers per shot 500 • 934,162 days of render time on one CPU – they used 1200 CPUs = 778 days of rendering Prof.Sonal Badhe
- 173. 173 Final Fantasy • Renderman (Pixar) used for rendering – direct illumination – many hacks to fake global illumination • Maya used for modeling • Hair – Modeled is splines – Lighting and rendering complicated as well Prof.Sonal Badhe
- 174. 174 Star Wars I • The good – Jar-Jar’s ears (cloth simulation) – Jar-Jar’s facial animation – Sets • Were only as high as the tallest character in the film • Above that was all CG – Was the first interaction between CGI and humans Prof.Sonal Badhe