虛擬現(xiàn)實(shí)技術(shù)實(shí)驗(yàn)教案

實(shí)驗(yàn)一VRML基本造型一、實(shí)驗(yàn)?zāi)康?.熟悉VRML瀏覽器的安裝及使用方法。2.了解VRML編輯器vrmlpad的安裝及基本用法。3.了解VRML語(yǔ)言的基本語(yǔ)法。4.掌握VRML語(yǔ)言創(chuàng)建的基本幾何造型。二、實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：1.WindowsXP操作系統(tǒng)2.虛擬現(xiàn)實(shí)瀏覽器插件BS_Contact_VRML-X3D.3.VRML編輯器vrmlpad.三、實(shí)驗(yàn)原理任何一個(gè)VRML場(chǎng)景中的幾何造型都必須以Shape節(jié)點(diǎn)進(jìn)行創(chuàng)建，場(chǎng)景造型包括基本的立方體、圓柱、圓錐、圓、文本造型等。四、實(shí)驗(yàn)步驟實(shí)例1.圓柱基本幾何造型。1.輸入下例。#VRMLV2.0utf8#Background{# skyColor1.01.01.0#}Shape{ appearanceAppearance{ materialMaterial{ } } geometryCylinder { top FALSE }}2.將本例中關(guān)于Cylinder節(jié)點(diǎn)的參數(shù)進(jìn)行更改，并觀察每個(gè)參數(shù)的影響。實(shí)例2.圓柱基本幾何造型。1.輸入下例。#VRMLV2.0utf8Background{ skyColor1.01.01.0}Shape{ appearanceAppearance{ materialMaterial{ } } geometrySphere { radius1.6 }}2.將Sphere節(jié)點(diǎn)的參數(shù)進(jìn)行更改，并觀察更改后的效果。實(shí)例3.長(zhǎng)方體等基本幾何造型的例子。#VRMLV2.0utf8Shape{ appearanceAppearance{ materialMaterial{ } } geometryBox{ }}實(shí)驗(yàn)二VRML空間變換實(shí)驗(yàn)?zāi)康?．理解VRML空間變換的原理。2．掌握Transform節(jié)點(diǎn)的用法。實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：1.WindowsXP操作系統(tǒng)2.虛擬現(xiàn)實(shí)瀏覽器插件BS_Contact_VRML-X3D.3.VRML編輯器vrmlpad.實(shí)驗(yàn)原理VRML場(chǎng)景中的每一個(gè)造型都是基于當(dāng)前坐標(biāo)系進(jìn)行創(chuàng)建的，而單一坐標(biāo)系的使用將在很大程度上限制用戶的空間想象力和創(chuàng)造力的發(fā)揮。在VRML場(chǎng)景中改變空間位置和空間朝向，需要進(jìn)行VRML空間變換，也即變換造型創(chuàng)建所基于的空間坐標(biāo)系。VRML空間變換使用Transform節(jié)點(diǎn)進(jìn)行。其主要的語(yǔ)法格式如下：Chilidren []Translation 0.00.00.0Rotation 0.00.01.00.0Scale 1.01.01.0scaleOrientation 0.00.01.00.0Center 0.00.00.0Bboxcenter 0.00.00.0bboxSzie -1.0-1.0-1.0addChildrenremoveChildren實(shí)驗(yàn)內(nèi)容與步驟實(shí)例1.樓梯造型代碼如下：#VRMLV2.0utf8DEF stairShape { appearanceAppearance{ materialMaterial{ } } geometryBox{ size1.51.05.0 }}Transform{ translation 1.30.80.0 children[ USE stair Transform{ translation 1.30.80.0 children[ USE stair Transform{ translation 1.30.80.0 children[ USE stair ] } ] } ]}效果圖如下：實(shí)例2.立體鼠標(biāo)代碼如下：#VRMLV2.0utf8Background{ skyColor1.01.01.0}DEF acrossmouseShape{ appearanceAppearance{ materialMaterial{ diffuseColor1.01.00.0 } } geometryCylinder{ radius0.2 height4.0 }}Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.60.40.2 } } geometryBox{ }}Transform{ rotation1001.571 children[ USE acrossmouse ]}Transform{ rotation0011.571 children[ USE acrossmouse ]}效果圖如下：實(shí)例3.嵌套使用代碼如下：#VRMLV2.0utf8Background{ skyColor1.01.01.0}Group{ children[ Shape{ appearanceAppearance{ materialMaterial{ emissiveColor1.00.80.2 transparency0.5 } } geometrySphere { radius2.0 } } DEF spaceTransform { translation 400 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor1.00.00.0 } } geometrySphere { radius0.5 } } ] } Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space Transform{ rotation0010.785 children[ USE space ] } ] } ] } ] } ] } ] } ] } ]}2.效果如下：實(shí)驗(yàn)三VRML材質(zhì)及紋理實(shí)驗(yàn)?zāi)康?．理解VRML材質(zhì)及紋理的主要作用。2．掌握VRML材質(zhì)及紋理節(jié)點(diǎn)的用法。實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：1.WindowsXP操作系統(tǒng)2.虛擬現(xiàn)實(shí)瀏覽器插件BS_Contact_VRML-X3D.3.VRML編輯器vrmlpad.實(shí)驗(yàn)原理造型的材質(zhì)屬性包括造型的反光顏色、發(fā)光顏色、明亮程度以及透明度等。造型的材質(zhì)控制使用Appearance節(jié)點(diǎn)的material域的域值設(shè)置，material域的域值所使用的材質(zhì)節(jié)點(diǎn)為Material節(jié)點(diǎn)。VRML紋理映射是通過(guò)將數(shù)字紋理根據(jù)幾何體的外形，按一定規(guī)則映射到幾何造型或文本造型的表面。紋理映射是包括VRML在內(nèi)的各種三維技術(shù)廣泛使用的一種增效渲染方法。該方法通過(guò)在造型表面映射具有微觀細(xì)節(jié)的數(shù)字紋理，極大地改善了單純使用Material節(jié)點(diǎn)進(jìn)行材質(zhì)渲染所呈現(xiàn)的視覺(jué)宏觀效果。本實(shí)驗(yàn)涉及到的主要節(jié)點(diǎn)：Appearance{materialtexturetextureTransform}ImageTexture{url( )repeatSrepeatY}TextureTransform{translation 0.0 0.0rotation 0.0scale 1.0 1.0center 0.0 0.0}實(shí)驗(yàn)內(nèi)容與步驟實(shí)例1.廣告牌。代碼如下：#VRMLV2.0utf8Shape{ appearanceAppearance{ texture ImageTexture{ url "2.jpg" } } geometryBox{ size220.04 }}Transform{ translation 00-0.1 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor011 } } geometryBox{ size220.16 } } ]}2．其效果如下：實(shí)例2.視頻紋理。1.代碼如下：#VRMLV2.0utf8Background{ skyColor111}Transform{ translation 00-0.1 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.50.60.1 } } geometryBox{ size1580.2 } } ]}Shape{ appearanceAppearance{ textureDEF mpegMovieTexture{ url "dahanzhan.mpeg" loopTRUE # speed0.1 } } geometryBox{ size1270.1 }}效果圖如下：實(shí)例3.紋理縮放。代碼如下：#VRMLV2.0utf8Background{ skyColor0.60.20.2}Shape{ appearanceDEFaaAppearance{ texture ImageTexture{ url "front.bmp" #repeatS TRUE repeatT FALSE } textureTransformTextureTransform{ scale 22 } } geometryBox{ size20102 }}Transform{ translation 00-2 children[ Shape{ appearanceUSEaa geometrySphere { } } ]}效果如下： 實(shí)驗(yàn)四視點(diǎn)與導(dǎo)航實(shí)驗(yàn)?zāi)康?．掌握VRML視點(diǎn)及導(dǎo)航控制實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：1.WindowsXP操作系統(tǒng)2.虛擬現(xiàn)實(shí)瀏覽器插件BS_Contact_VRML-X3D.3.VRML編輯器vrmlpad.實(shí)驗(yàn)原理VRML所提供的視點(diǎn)是在所瀏覽的場(chǎng)景中預(yù)先由用戶定義的觀察位置及空間朝向。在這個(gè)位置且通過(guò)該朝向，用戶可以瀏覽到虛擬世界中相應(yīng)場(chǎng)景的指定部分。同一個(gè)VRML場(chǎng)景中可以設(shè)置許多個(gè)視點(diǎn)，但一次瀏覽只有一個(gè)視點(diǎn)是可用的。視點(diǎn)控制通過(guò)Viewpoint節(jié)點(diǎn)進(jìn)行實(shí)現(xiàn)。虛擬場(chǎng)景中，NavigationInfo導(dǎo)航信息節(jié)點(diǎn)用來(lái)提供瀏覽者化身信息以及該化身如何使用當(dāng)前的視點(diǎn)進(jìn)行系統(tǒng)導(dǎo)航。實(shí)驗(yàn)內(nèi)容與步驟實(shí)例1.視點(diǎn)應(yīng)用代碼如下#VRMLV2.0utf8Background{ skyColor0.850.850.85}Viewpoint{ position0.00.016.0 description "view1"}Viewpoint{ position0.00.03.0 description "v2"}Viewpoint{ orientation 001-0.0 description "v3"}Viewpoint{ orientation 0011.571 description "v4"}Viewpoint{ fieldOfView 0.1 description "v5"}Viewpoint{ fieldOfView 1.571 orientation 001-3.14 description "v6"}Viewpoint{ description "v7" position001}Group{ children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.20.40.6 } } geometryCone{ bottomRadius1 height2 } } Transform{ translation 01.40 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.20.40.6 } } geometryBox{ size0.80.80.8 } } ] } ]}2．效果如下： 視點(diǎn)一 視點(diǎn)二 視點(diǎn)三 視點(diǎn)四 視點(diǎn)五 視點(diǎn)六實(shí)例2.導(dǎo)航控制代碼如下用到的實(shí)例#VRMLV2.0utf8Group{ children[ DEF ylineGroup { children[ DEF xlineGroup { children[ DEF oneGroup{ children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.690.360.93 specularColor0.530.530.53 ambientIntensity0.1 shininess0.9 } } geometrySphere {} } Transform{ translation 0-1.30 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor110 specularColor0.820.280.28 ambientIntensity0.12 shininess0.8 } } geometryCone{} } ] } ] } Transform{ translation -400 children[ USE one ] } Transform{ translation 400 children[ USE one ] } ] } Transform{ translation 0-40 children[ USE xline ] } Transform{ translation 040 children[ USE xline ] } ] } Transform{ translation 00-4 children[ USE yline ] } Transform{ translation 004 children[ USE yline ] } ]}導(dǎo)航設(shè)置代碼一：#VRMLV2.0utf8NavigationInfo{ type"WALK"}Viewpoint{ position0022}Inline{ url "e12.2.wrl"}導(dǎo)航設(shè)置代碼二：#VRMLV2.0utf8NavigationInfo{ speed0}Viewpoint{ position0020}Inline{ url "e12.2.wrl"}實(shí)驗(yàn)五VRML動(dòng)畫一、實(shí)驗(yàn)?zāi)康?.掌握VRML動(dòng)畫的基本機(jī)理。2.掌握VRML的5中基本動(dòng)畫，并能自由地進(jìn)行程序設(shè)計(jì)。二．實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：1.WindowsXP操作系統(tǒng)2.虛擬現(xiàn)實(shí)瀏覽器插件BS_Contact_VRML-X3D.3.VRML編輯器vrmlpad.三、實(shí)驗(yàn)原理VRML動(dòng)畫依據(jù)一個(gè)給定的時(shí)間傳感器以及一系列插補(bǔ)器節(jié)點(diǎn)對(duì)場(chǎng)景中的動(dòng)畫進(jìn)行控制。節(jié)點(diǎn)不但擁有域?qū)傩?，還有事件屬性，分為出事件和入事件eventOut,eventIn，域則分為私有域和公共域exposedField。某個(gè)節(jié)點(diǎn)的事件出口和其他節(jié)點(diǎn)的事件入口之間用于傳遞事件的通道稱為路由。通常情況下，時(shí)間傳感器的startTime域被另一個(gè)對(duì)用戶動(dòng)作做出反應(yīng)的傳感器或腳本傳來(lái)的時(shí)間事件設(shè)置。在startTime設(shè)定的時(shí)刻以前，時(shí)間傳感器不產(chǎn)生任何事件，在該時(shí)刻到來(lái)時(shí)，將產(chǎn)生值為TRUE的isActive事件，并開始產(chǎn)生time,cycleTime和fraction_changed事件，time事件是一個(gè)總保持當(dāng)前時(shí)刻值的連續(xù)發(fā)生的事件，而其他與時(shí)間相關(guān)的事件則是周期性發(fā)生的事件。四、實(shí)驗(yàn)步驟實(shí)例1.朝向插補(bǔ)器動(dòng)畫#VRMLV2.0utf8Background{ skyColor111}DEF barTransform{ translation -6.000 children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.50.30 ambientIntensity0.4 specularColor0.70.70.6 shininess0.20 } } geometryCylinder{ height6.0 radius0.2 } } ]}DEF clockTimeSensor{ cycleInterval8 loopTRUE}DEF inter1OrientationInterpolator{ key [ 00.1250.25 0.3750.50.625 0.750.8751.0 ] keyValue[ 00-10 00-10.875 00-11.571 00-12.356 00-13.141 00-1 3.926 00-14.711 00-15.496 00-16.281 ]}DEF inter2PositionInterpolator { key [ 00.51.0 ] keyValue[ -600 000 600 ]}ROUTEclock.fraction_changedTO inter1.set_fractionROUTEinter1.value_changedTObar.set_rotationROUTEclock.fraction_changedTO inter2.set_fraction#ROUTEinter2.value_changedTObar.set_translation效果圖如下，該實(shí)例實(shí)現(xiàn)了物體自由轉(zhuǎn)動(dòng)的效果。實(shí)例2.位置插補(bǔ)器動(dòng)畫#VRMLV2.0utf8Background{ skyColor111}DEF ballTransform{ children[ Shape{ appearanceAppearance{ materialMaterial{ diffuseColor0.580.510.09 specularColor0.920.430.01 ambientIntensity0.117 shininess0.4 } } geometrySphere {} } ]}DEF clockTimeSensor{ cycleInterval10 loopTRUE}DEF interPositionInterpolator{ key [ 00.330.671 ] keyValue[ -3.000 3.000 030 -300 ]}ROUTEclock.fraction_changedTO inter.set_fractionROUTEinter.value_changedTOball.set_translation該實(shí)例實(shí)現(xiàn)了造型的自由運(yùn)動(dòng)實(shí)例3.標(biāo)量插補(bǔ)器動(dòng)畫#VRMLV2.0utf8Background{ skyColor111}DEF rotTransform{ children[ Shape{ appearanceAppearance{ materialDEFcolorMaterial { diffuseColor0.80.50.8 transparency0 } } geometrySphere { radius2 } } Shape{ appearanceAppearance{ materialMaterial{ diffuseColor100 } } geometryCone{ bottomRadius1 height2 } } ]}DEF clockTimeSensor{ cycleInterval10 loopTRUE}DEF inter1ScalarInterpolator{ key [ 00.250.50.751 ] keyValue[ 00.500.50 ]}DEF inter2OrientationInterpolator{ key [ 00.1250.250.375 0.50.6250.750.875 1 ] keyValue[ 1110.0 1110.785 1111.571 1112.356 1113.141 1114.711 1115.496 1116.281 ]}ROUTEclock.fraction_changedTO inter1.set_fractionROUTEinter1.value_changedTOcolor.set_transparencyROUTEclock.fraction_changedTO inter2.set_fractionROUTEinter2.value_changedTOrot.set_rotation該實(shí)例通過(guò)標(biāo)量插補(bǔ)，實(shí)現(xiàn)了物體透明度的變化。實(shí)驗(yàn)六Cult3D技術(shù)一、實(shí)驗(yàn)?zāi)康?．掌握Cult3D技術(shù)的特點(diǎn)，了解Cult3D技術(shù)的應(yīng)用領(lǐng)域2．掌握Cult3D軟件的安裝與運(yùn)行，Cult3D作品的瀏覽3．掌握Cult3D軟件的基本操作。二、實(shí)驗(yàn)器材硬件環(huán)境：多媒體計(jì)算機(jī)軟件環(huán)境：可用WindowsXP操作系統(tǒng)，Cult3D軟件三、實(shí)驗(yàn)原理Cult3D的開發(fā)過(guò)程比較簡(jiǎn)單，如圖所示，經(jīng)過(guò)三步，就可以制作出Cult3D的作品。四、實(shí)驗(yàn)步驟實(shí)例1.基本三維展示（演示實(shí)驗(yàn)）在這個(gè)實(shí)例中，主要介紹如何制作對(duì)物體進(jìn)行三維展示，用鼠標(biāo)的左鍵對(duì)物體旋轉(zhuǎn)，鼠標(biāo)的右鍵對(duì)物體進(jìn)行放與縮小，鼠標(biāo)的左右鍵同時(shí)按下時(shí)則移動(dòng)這個(gè)物體的位置。1.啟動(dòng)程序。2.添加openbox.c3d素材文件(實(shí)例1的作品文件)。3.將EventMap窗口中的Leftmouseclickonobject拖入