520527: 520527 Computer Graphics


Resources: Resources Textbook Computer Graphics Using OpenGL by F.S. Hill. 2nd Edition. Prentice Hall ISBN:002354856 หนังสืออ่านประกอบ Computer Graphics with Pascal by Mare Berger , Benjamin Cummings Publishing Company Software Visual C++ OpenGL GLUT Libraries


What won’t I learn?: What won’t I learn? Painting and Imaging Software (Paintshop Pro, Adobe Photoshop) CAD Packages (AutoCAD) Animation Software (Maya) Rendering Software (Renderman) 3D Modelling (3D Studio Max)


What skills should I already have?: What skills should I already have? Programming Programming Programming Turbo C Visual C++


Computer Graphics: Computer Graphics Pictures are generated by a computer Tools used to make pictures HW & SW video monitors , printer , mouse ,track ball os, editor,compiler, graphics library


Computer graphics are used: Computer graphics are used 1.Art , Entertainments , Publishino Movie production Animation (20-30 frame per sec.) Special Effects Computer Games Browsing on World Wide Web


2.Computer-Aides design: 2.Computer-Aides design


GE introduces first full color real time flight simulator for NASA: GE introduces first full color real time flight simulator for NASA 3. Displaying Simulations


Simulation/Training: Simulation/Training Flight


Simulation/Training: Simulation/Training Truck Driving


4.Scientific Analysis Visualization : 4.Scientific Analysis Visualization Scientific data are complex


5. Image processing: 5. Image processing


what is computer graphics?: what is computer graphics? “Computer Graphics is concerned with producing images using a computer.” Modelling The representation of the form of objects Rendering The appearance of objects Animation The movement of objects


what is computer graphics?: what is computer graphics? Modelling Taking the real and turning it into the virtual. Explaining real world or fantastic objects using mathematics. If the image does not exist in real life, a blueprint is drawn by an artist.


what is computer graphics?: what is computer graphics? Rendering Drawing the Image Colour Lighting Shading Surface Texture Shadows Reflection and Transparency Intersection


what is computer graphics?: what is computer graphics? Animation Controlling the movement of objects. Laws of Physics Biomechanics/ Kinesiology Lip Sink Special Effects


Progression of a CG Character: Progression of a CG Character


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1885 - CRT (Cathode Ray Tube)


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1887 - Edison patents motion picture camera 1888 - Edison and Dickson record motion picture photos on a wax cylinder


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1926 – J.L. Baird invents the television. 30 line vertical, black and red scan.


A Brief History of Computer Graphics: A Brief History of Computer Graphics early graphics using VectorScope (1951)


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1962 Sketchpad developed by Ivan Sutherland Lightpen used to create engineering drawings directly on the CRT. zoom in and out on the display and the ability to make perfect lines, corners, and joints.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1962 SpaceWar created by Steve Russell First computer game Multiplayer game The "a", "s", "d", "f" keys control one of the spaceships. The "k", "l", ";", "'" keys control the other.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1963 IBM creates the 360 models One of the First General Purpose Mainframes develops the mouse.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1967 GE introduces first full colour real time flight simulator for NASA


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1972 ATARI Pong


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1974 Intel develop the 8080 processor. Bill Gates starts Microsoft


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1976 Steve Jobs and Steve Wozniak start Apple. 1977 Academy of Motion Pictures Art and Sciences introduces Visual Effects category for Oscars.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1977 Star Wars wins oscar for special effects. 1978 Superman wins oscar for special effects.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1981 IBM introduces the first IBM PC (16 bit 8088 chip) Raiders of the Lost Ark wins an oscar for visual effects.


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1983 First Coke Polar Bears Commercial


A Brief History of Computer Graphics: A Brief History of Computer Graphics 1984 PIXAR Opens


Cathode-ray tube: Cathode-ray tube Display Technologies


Color CRT Monitor: Color CRT Monitor Display Technologies


CRT มี 2 ชนิด 1.rester scan  2.random vector: CRT มี 2 ชนิด 1.rester scan 2.random vector


Raster Scan display: Raster Scan display


Raster Scan display: Raster Scan display pixel horizontal line เรียกว่า raster scan line Quality ขึ้นอยู่กับความละเอียด( Resolution ) วัดตามจำนวน raster scan line และ จำนวน pixel บนline (dot per unit area) low Resolution = 300 scan line , line ละ 400 Pixels high-Resolution = 1000 scan line , line ละ 1000 pixel อย่างน้อย


Slide50: Refresh Rate นับจำนวนครั้งที่ยิงประจุลบครบรอบในเวลา 1วินาที 1/Refresh rate = frame time Inexpensive display = 30 times/sec Odd-numbered raster line Even-numbered raster line Higher quality raster scan refresh – 60 times/sec


Raster Scan Display Unit : Raster Scan Display Unit Scan Conversion Frame Buffer Display Image Display Processor Memory Display Controller


Frame Buffer: Frame Buffer คือหน่วยความจำ ที่เก็บ pixel ที่ปรากฎอยู่บนจอภาพ Bit Map ในรูปตาราง Row ของ Frame Buffer = จำนวนเส้น Raster Scan Column ของ Frame Buffer=จำนวน pixel ในเส้น Raster Scan Ex 512 x 512 display = 262,144 pixel memory location


Slide53: 1 0 0 1 1 0 1 1 0 1 1 1 0 1 1 Frame Buffer Display Screen


Data in frame buffer: Data in frame buffer ใช้แทน Pixel แต่ละจุด 1 bit-plane frame buffer = ใช้ในจอภาพขาวดำความเข้ม 2 ระดับ Framebuffer ใช้ 3 bit = ได้ 8 ค่าความเข้ม


Frame Buffer to CRT : Frame Buffer to CRT


Display Controller: Display Controller หน่วยการแสดงภาพ หรือตัว Control การแสดงภาพ ทำหน้าที่อ่าน Data จาก Frame buffer มาแสดงผลบน CRT TV ขาวดำ = 8 bit = 28 = 256 ระดับ สี = 24 bit = 224 = 16,772,216 ถ้าจอ 512 x 512 มีสี ต้องใช้ Frame buffer 512 x 512 x 24 = 6,291,456 bit


Random-Vector Display: Random-Vector Display Memory = display file เก็บคำสั่งเกี่ยวกับการแสดงภาพ Display File CRT


Comparison of Raster-Scan and Random-Vector display: Comparison of Raster-Scan and Random-Vector display


Comparison of Raster-Scan and Random-Vector display: Comparison of Raster-Scan and Random-Vector display


Slide60: random vector ต้องการ memory < Frame buffer random Vector Modify ส่วนของภาพได้เร็วกว่า เพราะทำงานเพียงเป็น coordinate บน displaylist ข้อเสีย Random Vector ไม่เหมาะกับการระบาย การสร้างภาพที่มีแสงเงาเหมือนจริง Complexity ของภาพ มีขีดจำกัด ขึ้นอยู่กับความสามารถของระบบที่จะเขียนซ้ำภาพ (Refresh Cycle)