Introduction to Computer Graphics Sushil Kumar
What is Computer Graphics? Computer graphics is an art of drawing pictures, lines, charts, etc using computers with the help of programming. Computer graphics is made up of number of pixels. Pixel is the smallest graphical picture or unit represented on the computer screen.
Types of computer graphics Interactive Computer Graphics: Interactive Computer Graphics involves a two way communication between computer and user. Here the observer is given some control over the image by providing him with an input device for example the video game controller of the ping pong game. This helps him to signal his request to the computer.
Types of computer graphics Non Interactive Computer Graphics: In non interactive computer graphics otherwise knowrn as passive computer graphics. it is the computer graphics in which user does not have any kind of control over the image. Image is merely the product of static stored program and will work according to the instructions given in the program linearly. The image is totally under the control of program instructions not under the user. Example: screen savers.
What is Interactive Computer Graphics? User controls content, structure, and appearance of objects and their displayed images viarapid visual feedback Basic components of an interactive graphics system input (e.g., mouse, stylus, multi-touch, in-air fingers.. . ) processing (and storage of the underlying representation/mode display/output (e.g., screen, paper-based printer, video recorder...)
What is Non Interactive (Batch) Computer Graphics Today, still use non-interactive batch mode for final production- quality videoand film (special effects-FX). Rendering a single frame of Monsters University (a 24 fps movie) averaged 29 hours on a 24,000-core render farm!
Enabling Modern Computer Graphics Hardware revolution every 12-18 months, computer power improves by Moore s Law factor of 2 in price / performance as size shrinks Newest CPUs are 64-bit with 2, 4, 6, 8, even up to 18 cores Intel Skylake-consumer processor with 4 cores, 8 threads, and a fully featured graphics chip built in to the processor Significant advances in commodity graphics chips every 6 months vs. several years for general purpose CPUs NVIDIA GeForce GTX Titan X 3072 cores, 12GB memory, and 7 teraflops of processing power in a single chip
Enabling Modern Computer Graphics Graphic subsystems Offloads graphics processing from CPU to chip designed for doing graphics operations quickly nVidia GeForce"M AMD RadeonTM and Intel HD and Iris Pro Graphics GPUs originally designed to handle special-purpose graphics computations Increasingly, GPUs used to parallelize other types of computation (known as GPGPU, or General-Purpose Computing on the Graphics Processing Unit
Enabling Modern Computer Graphics Input Devices Mouse, tablet & stylus, multi-touch, force feedback, and other game controllers (e.g., Wii), scanner, digital camera (images, computer vision), etc. Body as interaction device X-Box- Kinect Leap Motion PlayStation Move
Conceptual Framework for Interactive Graphics intermediary Graphics library/package is hardware (Graphics System) Application program maps application objects to views (images) of those objects by calling on graphics library. Application model may contain lots of non-graphical data (e.g., non-geometric object properties) User interaction results in modification of image and/or model This hardware and software framework is 5 decades old but is still useful between application and display Software Hardware Graphics System/ Application Graphics Application Model database Program