計(jì)算機(jī)圖形學(xué)-Computer-Graphics-Overview

ComputerGraphics課件制作：賈世宇主 講：何辰Applications

of

Computer

GraphicsGUI(Graphical

User

Interface)(圖形用戶(hù)接口）Computer

Aided

Design(CAD)（計(jì)算機(jī)輔助設(shè)計(jì)）Data

Visualization（數(shù)據(jù)可視化）Virtual

Reality（虛擬現(xiàn)實(shí)）Simulators（模型）Movie

special

effects（動(dòng)畫(huà)特殊效果）Games(游戲）The

Graphics

Rendering

Pipeline（圖形渲染流水線(xiàn)）3D

SCENE

IMAGECollection

of

3D

primitive（幾何模型）

Array

of

pixelsPrimitives:

Basic

geometric

structures

(points,

lines,

triangles3DPrimitives2DPrimitivesPixelsGeometryStageRasterizationStageVertex

ProcessingPixel

ProcessingCoordinateTransformationLightingCalculationPrimitive

RasterizationVertex

AttributeInterpolationTexture

MappingRaster

Operation

(ROP)Scissor

Test

Alpha

TestStencil

TestDepth

(Z)

TestColor

Blending光柵掃描Computer

Graphics

HardwareCPUSystemMemoryFrame

BufferVideo

ControllerVideoDisplayDeviceGraphics

ControllerVideo

MemoryPrimitive

DataTexture

DataMotherboardGraphics

CardBus

(PCI,

AGP,PCI

Express)Graphics

Hardware

ArchitectureVideo

Display

DevicesCRT

(Cathode-Ray

Tube)ElectronGunFocusingSystemHorizontalDeflectionPlatesVerticalDeflectionPlatesElectronBeamPhosphor-CoatedScreen電子槍垂直Color

CRTElectronGunRedBlueGreenShadowMaskScreenPhosphor-DotTriangleRaster-Scan

DisplaysVertical

RetraceScan

line

(row

ofpixels)Horizontal

RetraceRefresh

rate:

Number

of

times

an

entire

screen

is

repainted

in

a

secondProgressive-scan:

Scan

lines

are

repainted

one

by

one.Interlace:

Repaint

even-numbered

scan

lines,

then

odd-numbered

scan

lRandom-Scan

Displays

(Vector

Displays)Display

list

:

Sequence

of

line-drawing

commands.Display

listLine

(0,0)-(100,0)Line

(100,0)-(50,50)Line

(50,50)-(0,0)LCD(Liquid-crystal

Display)液晶顯示器

Passive-matrix

LCDLiquid

CrystalVerticalTransparentConductorHorizontalTransparentConductorLightPolarizerLightPolarizerLightActive-matrix

LCDTransistor

at

each

pixel

location.

TFT

(Thin-Film

Transistor)Flat-Panel

DisplaysPlasma

DisplayGas

(Neon

mixture)VerticalTransparentConductorHorizontalTransparentConductorThree-Dimensional

Viewing

DevicesStereoscopic

vision:

two

different

views

for

left

and

right

eye.Left

eye Right

eyeRed-Green

glasses.Polarized

glasses.Synchronized

shutter

glasses.

New

device

without

glasses.

LCD

with

optical

raster

and

motiontracker.The

frame

buffer:

Video

memory

that

holds

screen

pixel

valResolution:

Number

of

horizontal

and

vertical

pixels

on

thThe

Frame

Buffer00h-1w-1(x,

y)xyColor

valuePixel

value

Depth

(Z)

valueStencil

valueStencil

BufferFrame

BufferColor

BufferDepth

(Z)

buffer定位Color

depth

(Color

bits):

Number

of

bits

in

color

buffer

trepresents

color

value

of

one

pixel.1

bit:8

bit:monochrome.

Bitmap256

color16

bit:

high

color24

bit:true

color（真彩色）

(8

bit

for

red,green,blue)32

bit:true

color

plus

alpha

value(transparency)The

color

value

can

directly

describe

color

components,

ocan

be

a

color

index

into

a

color

table.Depth

bits:

Number

of

bits

in

depth

buffer

that

representsvalue

of

one

pixel.Stencil

bits:

Number

of

bits

in

stencil

buffer

that

represvalue

of

one

pixel.Horizontal

resolution

wVertical

resolution

hColor

bits

ncDepth

bits

ndStencil

bits

nsNumber

of

bytes

needed

for

color

buffer:

wNumber

of

bytes

needed

for

depth

buffer:

wNumber

of

bytes

needed

for

stencil

buffer:

wh

nc

/

8h

nd

/

8h

ns

/

8Address

of

pixel

(x,

y)

in

color

buffer:Double

bufferTwo

color

buffers.

Front

stage

for

display.

Back

stage

forFront

stage

and

back

stage

swapping

for

animation.colorbuffer

1colorbuffer

2Front

stagepointerBack

stagepointercolorbuffer

1colorbuffer

2Front

stagepointerBack

stagepointerTriple

bufferThree

color

buffers.

One

front

stage

and

two

back

stages.Video

ControllerMain

function:

Periodically

read

pixel

color

values

frombuffer,

converts

them

into

video

signals

and

send

video

sito

video

display

devices.Other

functions:Double

buffer

or

triple

buffer

operationColor

table

lookupVideo

overlayGraphics

ControllerThe

evolution

of

graphics

controllerBefore

1995:

Primitive

Rasterization1995-1998:

3D

Accelerator.

Texture

mappingand

Hardware

Z-buffer1999-2000:

GPU.

Hardware

Transformation

andLighting

Calculation

(Hardware

TnL)2001:

Programmable

Vertex

Shader2002-today:

Programmable

Pixel

ShaderGraphicsControllerRasterization

Stage1995-1998:

3D

AcceleratorCPUSystem

MemoryGraphicsApplicationGeometryStage2DPrimitivesTexturesRasterizerTextureUnitVideo

MemoryROPUnit2DPrimitivesTexturesFrameBufferBus(PCI)Features:Primitive

rasterizationTexture

mappingHardware

Z-bufferRepresentative

products:3dfx

Voodoo

seriesNVidia

TNT

seriesATI

Rage

seriesMatrox

MystiqueRendition

VeriteS3

Savage1999-2000:

GPU

(Graphics

Processing

Unit)GPURasterization

StageCPUSystemMemoryGraphicsApplication3DPrimitivesTexturesRasterizerMultiTextureUnitVideo

MemoryROPUnit3DPrimitivesTexturesFrameBufferBus(AGP)TextureCombinerGeometryStageTransformationAndLighting

UnitFeatures:Hardware

transformation

and

lighting

(TnL)

Superscalar

structure

(Multiple

vertex

and

pixelprocessing

units

working

in

parallel)Hardware

Z-buffer

and

Stencil-bufferRepresentative

products:NVidia

Geforce

256ATI

Radeon

7500Shader:

Part

of

graphics

hardware

pipeline

that

can

beprogrammed.Vertex

Shader

Unit:

Programmable

unit

that

controls

vertprocessing.Representative

products:NVidia

Geforce

3ATI

Radeon

85002002:

Programmable

Pixel

ShaderGPURasterization

StageCPUSystemMemoryGraphicsApplication3DPrimitivesTexturesRasterizerMultiTextureUnitVideo

MemoryROPUnit3DPrimitivesTexturesFrameBufferBus(AGP,PCIe)PixelShaderUnitGeometryStageVertexShaderUnitPixel

Shader

Unit:

Programmable

unit

that

controls

pixelprocessing.Representative

products:NVidia

Geforce

FXATI

Radeon

9700CPUGraphicsApplicationGraphicsAPIComputer

GraphicsSoftwareGPUPixelShaderUnitVertexShaderUnitGraphicsDriverVertexProgramPixelProgramBusGraphics

Software

ArchitectureGraphics

Applications3D

modeling

software

(3D

Studio,

Maya,

etc.)CAD

software

(Solidedge,

Solidworks,

Pro/E,

etc.)Medical

and

business

visualization

softwareComputer

gamesGraphics

APIAPI:Application

Programming

Inter（f應(yīng)ac用e程序接口）Low

level

APIOpenGL（Graphics

library)Direct3DHigh

level

APIOpen

InventorVRMLJava3DVertex

and

Pixel

ProgramAssembly

LanguageHLSL

(High

Level

Shading

Language)Cg

(C

for

Graphics)DirectX

HLSLGLSL

(OpenGL

Shading

Language)Components

of

Graphics

SoftwareOutput

primitives

(points,

lines,

polygons,

circles,Attributes

(line

color,

width,

style,

fill

pattern,

foCoordinate

transformationInput

functions

(keyboard,

mouse,

joystick,

etc.)Control

operations

(clear

screen,

initialize

parameteIntroduction

to

OpenGLOpenGL

(Open

Graphics

Library):API

for

3D

graphics

rendering.

Originally

developed

on

SGI

(software

grinterface)

workstation.

Became

an

open

standard

in

1992.Features:Open

standard.Hardware

independent.Cross-platform

(Unix,

Mac

OS,

Linux,

Microsoft

Windows).Cross-language

(Bindings

for

C,

C++,

Fortran,

Ada,

Java)Extensible

through

OpenGL

extension

mechanismWide

industry

supportLimitations:No

input

functions.No

text

rendering

functions.No

window

management

functions.OpenGL

versions1.1

(July

1,

1992)Adds

texture

objects,

texture

and

subtexture

copying,

vertex

array.1.2

(March

16,

1998)Adds

3D

texture,

separate

specular

color,

imaging

subsets.1.3

(August

14,

2001)Adds

compressed

texture,

cube

map

texture,

multitexture,

texturecombiner

function,

multisample

antialiasing.1.4

(July

24,

2002)Adds

depth

texture

and

shadows,

Fog

coordinates,

Point

parameters.1.5

(July

29,

2003)Adds

buffer

objects.2.0

(September

7,

2004)Adds

OpenGL

shading

language,

multiple

render

targets,

non-power-oftwo

texture,

point

sprites,

two-sided

stencil

operation.Useful

websites:3DLabsAppleATIDellIBMIntelNvidiaSGISun

MicrosystemsOpenGL

ARB(Architecture

Review

Board)NVidia

GeForce6800

(Code

name:

NV40)Graphics

Hardware

ExampleFrontBackThe

GPU

itself

(Heat

sink

and

fan

removed)222

Million

transistorsThree

times

the

number

of

transistors

in

Intel

Pentium

4

Northwood33%

more

transistors

than

Intel

Pentium

4

Extreme

Edition.GPU

clock:

400MHzMemory

clock:

550MHzVideo

Memory:

128/256/512

MBCineFX

3.0

Shading

ArchitectureSupport

for

Microsoft

DirectX

9.0

Vertex

Shader

3.0Support

for

Microsoft

DirectX

9.0

Pixel

Shader

3.0Up

to

16

textures

per

rendering

passDirectX

and

S3TC

texture

compressionFull

128-bit

floating

point

precision64-Bit

Texture

Filtering

and

BlendingIntellisample

3.0Advanced

16x

anisotropic

filteringRotated-grid

antialiasingAdvanced

lossless

compression

algorithms

for

color,

texture,

and

z-Fast

z-clearHigh-resolution

compression

technol