chapter 17 - dragonfly (trace images)

Chapter 17: Dragonfly - Trace Images

Thistutorialdemonstrateshowtogetstartedmodelinganobjectusingphotographsasreferencematerial.Youwilllearnhowto: Traceanimagetocreateprofilecurves. Createcross-sectioncurvesforloftingtheprofiles. Editcontrolpointstochangeasurfaceshape.

Starting images.

Finished model.

Note:Thetopandsideviewsareactuallyofdifferentspecimensofthisdragonfly.Inthesideview,thewingsarefoldedup.Wewillbeusingthesideviewimageonlytodrawthesideviewcurvesofthebody.

Draw the bodySincethedragonflyissymmetricalinthetopview,andthemodelisnotgoingtobeascientificreproduction,traceonesideofthedragonflyandmirrorthecurvetotheotherside.Forthesideview,drawtwocurvessincetheprofileisnotsymmetrical.Thenwewillloftcrosssectioncurvestomakethebody.Theheadwillbemadeseparately.Thetailandbodywillallbemadeinonepiece.Thetailisactuallyseveralsegmentsthatflex.Ifyouweremakingananimationorascientificmodel,youprobablywouldwanttodividethedragonflyintosmallersurfaces.

Start the model1. BeginaNewmodel.2. IntheTemplate Filedialogbox,selectSmall Objects - Millimeters.3dm,andclickOpen.

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Draw a reference line4 IntheTopviewport,usetheLinecommandtodrawareferenceline50 millimeterslongstarting

at0,0,0.

Place the top view image1. StartPictureFramecommand.

IntheTutorial ModelsfolderUser's Guide,youwillfindtheimagesyouneedforthisexercise.2. FindtheimagefileDragonFly Top.jpg,andplacetheimageintheTopviewport.

Usethereferencelinetosetthelengthofthepictureframeimage.

Move the image into place4 UseobjectsnapstoMovetheimagefromthemidpointoftheleftside(Mid)totheconstruction

planeoriginat0,0,0.

Place the side view image1. StartPictureFramecommand.

IntheTutorial ModelsfolderthatyoudownloadedwiththeUser's Guide,youwillfindtheimagesyouneedforthisexercise.

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2. FindtheimagefileDragonFly Side.jpg,andplacetheimageintheFrontviewport.Usethereferencelinetosetthelengthofthepictureframeimage.

3. Using Ortho, dragtheimagedownintheFrontviewportuntilthereferencelinematchesthecenterofthedragonflybody.

Prepare the view4 Hidethesideviewpictureframe.

Draw the outline curve4 IntheTopviewport,usetheCurvecommandtodrawanoutlineofthetophalfofthedragonfly

body.Useasmanycontrolpointsasyouthinkarenecessaryforthedetail.

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Drawonlyuptotheneck.Youwillbecreatingtheheadanotherway.

Mirror the curve4 IntheTopviewport,usetheMirrorcommandtocopythecurvearoundthereferenceline.

Thephotographshowsthatthedragonflyisnotsymmetricalaboutitscenterline.However,sinceyourdragonflywillbestylized,itdoesnotmatterinthiscase.Youcanchoosethelevelofaccuracyyouneed.

Show the side view image4 UsetheShowcommandtoshowtheside-viewpictureframeobject.

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Bend the curve4 IntheFrontviewport,usetheBendcommandtobendthecurvesdownatthetailtomatchthe

bendinthebodycurveinthatview.

Trace side-view body4 IntheFrontviewport,usetheCurvecommandtotracethebodyoutlineusingtwocurves,one

abovethereferencelineandonebelowthereferenceline.Maximizetheviewportandzoomin.Pickasmanypointsasyouneedtocreatethecurves.Usemorepointswhenroundingacornerandfewerpointsforastraightsection.

Prepare the view4 Hidethepictureframeobjectsandthereferenceline.

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Create the body surface4 UsetheCSeccommandtocreatecross-sectionprofilecurvesthroughthetop,bottom,andside

curves.Drawasmanycross-sectioncurvesasyouneedtomaintainthedetail.Youwillbeabletoseewhetheryouhaveenoughcurveswhenyouloftthesurfaceinthenextstep.Ifyoudonothaveenoughcurvestomaintaintheshapeinanarea,addmoreandretrythesurfaceloft.

Loft the body1. Selectallthecross-sectioncurvesyoujustcreated.2. UsetheLoftcommandtocreateasurfacethroughthecross-sectionprofiles.

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Draw the headDrawtheheadwithanellipsoidandmovethecontrolpointsaroundtodeformthehead.Theeyesarealsoellipsoids.Theneckisasurfaceblend.

Draw the head1. UsetheEllipsoidcommandwiththeDiameteroptiontostarttheellipsoidintheFrontviewport.2. UseElevator Modetopositionthefirstpoint.

AttheStart of first axisprompt,pressandholdtheCtrlkeyandintheTopviewportclicknearthesideofthehead.

3. IntheFrontviewport,movethecursoruptothecenteroftheheadinthesideviewandclick.

4. AttheEnd of first axisprompt,turnonOrthointheTopviewport,clickattheothersideofthehead.

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5. AttheEnd of second axisprompt,drawpickapointintheFrontviewporttoestablishtheheadsizefromfronttoback.WatchthepreviewintheTopviewporttochecktheoverallsize.

6. AttheEnd of third axisprompt,pickapointintheFrontviewportatthetopofthehead.

Note:Drawingtheellipsoidinthisorderandusingtheseviewportsisimportanttogetthepolesoftheellipsoidintherightplaceforthenextstep.

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Rebuild the ellipsoid4 UsetheRebuildcommandtoaddmorecontrolpointstotheellipsoid.

Setthepointcountto16intheu-directionand10inthev-direction.

Drag control points to shape the head1. UsethePointsOncommandtoturnoncontrolpointsfortheellipsoid.

2. IntheTopviewport,selectanddragpointsonbothsidesoftheellipsoidtowardthebacktodeformthehead.

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3. IntheRightviewport,dragthemiddletworowsofpointsdown.

Blend the head and bodyTheneckisablendsurfacebetweentheheadshapeandthebody.First,youaregoingtotrimtheheadshapetomakeanopening.

Trim the neck4 IntheFrontviewport,drawlinesasillustrated,andusetheTrimcommandtotrimtheheadand

bodyshapeswiththelines.

Blend the neck and body4 UsetheBlendSrfcommandtomakeablendsurfacebetweentheheadandbody.

Besuretheseamsarealignedandthedirectionarrowspointthesameway.

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Draw the eyesTheeyesaresimpleellipsoids.

Draw the base ellipsoid4 UsetheEllipsoidcommandtodrawtheeye.

Basethesizeandpositionontheimages.

Position the eye4 UsetheOrientcommandortheMoveandRotatecommandstoadjustthepositionoftheeye.

Mirror the other side.4 UsetheMirrorcommandtocopytheeyetotheotherside.

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Shape the tailTheendofthetailhasaroundedshapecutoutofit.UseaBooleantomakethisshape.

Cap the body1. Ifnecessary,extendthetailsectionbyturningonthecontrolpointsanddraggingthemtomatchthe

bitmap.2. UsetheCapcommandtomakethebodyintoasolid.

Draw a cutting cylinder4 UsetheCylindercommandtodrawasolidcylindersoitcutsthroughthetailasillustrated.

Boolean the tail4 UsetheBooleanDifferencecommandtocuttheendoutofthetail.

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Trace the wingsThewingsaresolidscreatedfromclosedcurves.Thelegsarecreatedbytracingapolylinedownthecenterofalegandusingapipesurfacetomakeaseriesoftubesaroundthepolyline.

Draw the outline curve4 IntheTopviewport,usetheCurvecommandtotracethewingsononesideofthedragonfly.

Extrude the curve to make a solid4 MakethecurvesintothinsolidswiththeExtrudeCrvcommand.

Setthecommand-lineoptionSolid=YestoYes.

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Move the wings into position4 PositionthewingsonthebackwiththeMovecommand.

Consultthesideviewimageofthedragonfly.Thefrontwingisslightlyhigherthanthebackwing.

Mirror the wings to the other side4 UsetheMirrorcommandtocopythewingstotheotherside.

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Draw the legsThelegsarepipedpolylineswithdifferentradiiatthestartandendofthepipes.

Draw the base polyline1. IntheTopviewport,usethePolylinecommandtotracedownthecenterofthelegs.2. EditthecontrolpointstopositionthelegsintheTopandFrontviewports.

Youwillhavetouseyourimaginationalittleforthissincethetwopicturesdonotshowthelegsofthesameinsect.

Pipe the legs4 UsethePipecommandtodrawthelegsaroundthepolylines.

Refertothebackgroundpicturetodeterminethestartingandendingdiameterofthepipe.

Mirror the legs4 UsetheMirrorcommandtocopythelegstotheotherside,ordrawdifferentlegsfortheotherside.

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Finishing touchesForaddedrealism,addcolor,reflectivity,andtransparency.

Render the model4 Addmaterialsandtexturesandrender.

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chapter 17 - dragonfly (trace images)

Documents

dragonfly trace imagesbend

dragonfly trace images2

view image1

curve4 inthefrontviewport

view body4 inthefrontviewport

finished model

starting images

inthetemplate filedialogbox