简介:Thispaperpresentsanewalgorithmforgenerating3DimagesofB-repsobjectswithtrimmedsurfaceboundaries.The3Dimageisadiscretevoxel-maprepresentationwithinaCubicFrameBuffer(CFB).Thedefinitionof3Dimagesforcurve,surfaceandsolidobjectareintroducedwhichimplytheconnectivityandfidelityrequirements.AdaptiveForwardDifferencingmatrix(AFD-matrix)for1D-3Dmanifoldsin3Dspaceisdeveloped.BysettingrulestoupdatetheAFD-matrix,theforwarddifferencedirectionandstepwisecanbeadjusted.Finally,anefficientalgorithmispresentedbasedontheAFD-matrixconceptforconvertingtheobjectin3Dspaceto3Dimagein3Ddiscretespace.
简介:Thetraditionalstrategyof3Dmodelreconstructionmainlyconcentratesonorthographicprojectionsorengineeringdrawings.Buttherearesomeshortcomings.Suchas,onlyfewkindsofsolidscanbereconstructed,thehighcomplexityoftimeandlessinformationaboutthe3Dmodel.Theresearchisextendedandprocesscardistreatedaspartofthe3Dreconstruction.Asetofprocessdataisasupersetof2Dengineeringdrawingsset.Thesetcomprisesprocessdrawingsandprocesssteps,andshowsasequencingandasymptoticcoursethatapartismadefromroughcastblanktofinalproduct.Accordingtothesecharacteristics,theobjecttobereconstructedistranslatedfromthecomplicatedengineeringdrawingsintoaseriesofmuchsimplerprocessdrawings.Withtheplentifulprocessinformationaddedforreconstruction,thedisturbancessuchasirrelevantgraph,symbolandlabel,etc.canbeavoided.Andmore,theformchangeofbothneighborprocessdrawingsissolittlethattheengineeringdrawingsinterpretationhasnodifficulty;inaddition,theabnormalsolutionandmulti-solutioncanbeavoidedduringreconstruction,andtheproblemsofbeingapplicabletomoreobjectsissolvedultimately.Therefore,theutilitymethodfor3Dreconstructionmodelwillbepossible.Ontheotherhand,thefeatureinformationinprocesscardsisprovidedforreconstructionmodel.Focusingonprocesscards,thefeasibilityandrequirementsofWorkingProcedureModelreconstructionisanalyzed,andthemethodtoapplyandimplementtheNaturalLanguageUnderstandingintothe3Dreconstructionisstudied.Themethodofasymptoticapproximationproductwasproposed,bywhicha3Dprocessmodelcanbeconstructedautomaticallyandintelligently.Theprocessmodelnotonlyincludestheinformationaboutpartscharacters,butalsocandelivertheinformationofdesign,processandengineeringtothedownstreamapplications.
简介:Itisaresearchsubjectincomputervisionto3Dreconstructionofanobjectrepresentedbyasingle2Dlinedrawing.Previousworkson3Dreconstructionfrom2Dlinedrawingsfocusonobjectswithlines,plane,view,andsoon.Thispapermainlystudiesthe3Dreconstructionfrom2Dlinedrawings.Besides,anewapproachisproposed:itisthatfortheresearchofthepointcoordinatesof2Dlinedrawings,soastoachievetheobjectreconstructionbythereconstructionofpointcoordinates.Thereconstructionprocessincludes:①thecollectionofpointcoordinates(X,Y)of2Dlinedrawings;②thederivationofmathematicalformulaaboutthereconstructionofthepointof2Dlinedrawings,andcalculatingthecorrespondingpointofthe3Dcoordinates;③theregenerationof3Dgraphicswith3Dpoints;④analyzeerrorbytheproportionalofparallelofaxonometricprojection,inordertoprovetheaccuracyofthemethod.
简介:Thispaperpresentsanefficienttechniqueforprocessingof3Dmeshedsurfacesviasphericalwavelets.Morespecifically,aninput3Dmeshisfirstlytransformedintoasphericalvectorsignalbyafastlowdistortionsphericalparameterizationapproachbasedonsymmetryanalysisof3Dmeshes.Thissignalisthensampledonthespherewiththehelpofanadaptivesamplingscheme.Finally,thesampledsignalistransformedintothewaveletdomainaccordingtosphericalwavelettransformwheremany3Dmeshprocessingoperationscanbeimplementedsuchassmoothing,enhancement,compression,andsoon.Ourmaincontributionliesinincorporatingafastlowdistortionsphericalparameterizationapproachandanadaptivesamplingschemeintotheframeforprocessing3Dmeshedsurfacesbysphericalwavelets,whichcanhandlesurfaceswithcomplexshapes.Anumberofexperimentalexamplesdemonstratethatouralgorithmisrobustandefficient.
简介:Thispaperpresentsadirectmethodtofindtheinternalfaces.Itusesfoursetsofinformation:1getthecoordinatesofeachpointonthe3Dcompositeobjects;2basedonthe3Dcoordinatestocalculatealltheplaneequationoftwoobjects;3calculatealltheintersectinglinesofthetwoobjectsandexcludetheintersectinglineswhicharenotwithinthescopeoftheplane;4findingtheinternalface,theremainingintersectinglinesformedtheplaneistheinternalfaceofthetwoobjects.Weproposedanewalgorithmforfindinginternalfaces.Thisalgorithmcouldbeadaptedtoanyregularcompositeobjects.Thealgorithmworkswellforfindinginternalfaces.