.obj loader for minib3d

This code has been declared by its author to be Public Domain code.

.obj loader for minib3d by klepto2

2007

This is one of some loaders I'm working on besides other things on minib3d.

This is a wavefront .obj loader. Currently I have disabled some material settings (ALpha eg)
and also the mesh is loaded with Brushflag 16 (doublesided rendering)

I hope you find it useful.
Please inform me about bugs you find.

SuperStrict

Framework klepto.minib3d


Graphics3D 800 , 600 , 0 , 2

Local Cam:TCamera = CreateCamera() 
CameraClsColor Cam , 0 , 0 , 255
PositionEntity Cam,0,0,-10
Local Light:TLight = CreateLight(1) 
Local File:String = RequestFile(".Obj file auswählen","obj files:obj",,CurrentDir())
Local Test:TMesh = LoadObj(File)

Local Wire:Byte = False
While Not KeyHit(KEY_ESCAPE) 
	TurnEntity Test , .03 , 0 , .03
	PositionEntity Light , EntityX(Cam) , EntityY(Cam) , EntityZ(Cam) 
	PointEntity Light,Test	
	Wireframe(Wire) 
	
	If KeyHit(Key_W) Then Wire = Not Wire
	
	If KeyDown(KEY_UP) Then MoveEntity cam,0,0,1.0*TGlobal.GetDelta()'RY:+0.5
	If KeyDown(KEY_DOWN) Then MoveEntity cam,0,0,-1.0*TGlobal.GetDelta()
	If KeyDown(KEY_RIGHT) Then MoveEntity cam,1.0*TGlobal.GetDelta(),0,0
	If KeyDown(KEY_LEFT) Then MoveEntity cam,-1.0*TGlobal.GetDelta(),0,0
	

	RenderWorld
	UpdateWorld
	Flip 0
Wend

Function LoadObj:TMesh(url:String)
	Local Stream:TStream = ReadStream(url) 
	If Not Stream Then Return CreateCube() 
	Local matlibs:TMap = CreateMap()
	Local VertexP:TObjVertex[60000]
	Local VertexN:TObjNormal[60000]
	Local VertexT:TObjTexCoord[60000]
	Local Faces:TFaceData[60000]
	Local gname:String = ""
	Local snumber:Int = -1
	Local curmtl:String = ""
	Local Readface:Byte = True
	Local dir:String = ExtractDir(url) + "/"
	If dir = "/" Then dir = ""
	'Print dir

	Local VC:Int = 0
	Local VN:Int = 0
	Local VT:Int = 0
	Local FC:Int = 0
	Local SC:Int = 0
	DebugLog "File " + url + " found !!!"
	Local Mesh:TMesh = CreateMesh() 
	Local Surface:TSurface '= CreateSurface(Mesh) 
	While Not Eof(Stream) 
		Local Line:String = ReadLine(Stream).Trim()
		If Line <> "" Then
			
			If Line[0] = Asc("#") Then
				DebugLog(".Obj Comment : " + Line) 
			Else
				'DebugLog("Line : " + Line[0..2] + "-!")
				If Line[0..2].tolower() = "v " Then
					VertexP[VC] = New TObjVertex
					VertexP[VC].GetValues(Line[2..]) 
					VC:+1
				EndIf
				
				If Line[0..3].toLower() = "vn " Then
					VertexN[VN] = New TObjNormal
					VertexN[VN].GetValues(Line[3..]) 
					VN:+1
				EndIf
				
				If Line[0..3].toLower() = "vt " Then
				    VertexT[VT] = New TObjTexCoord
					VertexT[VT].GetValues(Line[3..]) 
					VT:+1
				EndIf	
				
				If Line[0..2].toLower() = "g " Then GName = Line[3..].tolower() 
				If Line[0..2].toLower() = "s " Then
						 snumber = Int(Line[3..]) 
						 Surface = CreateSurface(Mesh)
						' EntityFX Mesh,16
						SC:+1 
				EndIf
				'If Line[0..7].toLower() = "usemtl " Then curmtl = Line[7..].tolower() 
				If Line[0..7].toLower() = "mtllib " Then
					Local L:TObjMtl[] = ParseMTLLib(dir+Line[7..]) 
					For Local Obj:TObjMtl = EachIn L
						MapInsert(Matlibs , Obj.Name , Obj) 
					Next
				EndIf
				If Line[0..7] = "usemtl " Then
					Local Obj:TObjMtl = TObjMtl(MapValueForKey(MatLibs , Line[7..].Trim() ) )
					Print Line[7..]
					If Obj <> Null Then
						If Not surface Then Surface = CreateSurface(Mesh)
						PaintSurface(Surface , Obj.Brush) 
						Print "Surface Painted with " + Obj.name
					EndIf
				EndIf
				If Line[0..2].tolower() = "f " Then
					'Print its
					If Surface = Null Then Surface = CreateSurface(Mesh)
					If Surface Then
						
						Local V:TFaceData[] = ParseFaces(Line[2..])
																	
							For Local i2:Int = 2 To V.Length - 1
								Local V0:Int = AddVertex(Surface , VertexP[V[0].T[0]].X , VertexP[V[0].T[0]].Y ,- VertexP[V[0].T[0]].Z)',VertexT[V[0].T[1]].U,VertexT[V[0].T[1]].V) 
								Local V1:Int = AddVertex(Surface , VertexP[V[i2-1].T[0]].X , VertexP[V[i2-1].T[0]].Y ,- VertexP[V[i2-1].T[0]].Z)',VertexT[V[1].T[1]].U,VertexT[V[1].T[1]].V) 
								Local V2:Int = AddVertex(Surface , VertexP[V[i2].T[0]].X , VertexP[V[i2].T[0]].Y ,- VertexP[V[i2].T[0]].Z)',VertexT[V[2].T[1]].U,VertexT[V[2].T[1]].V) 
								
								If VertexN[0] <> Null
								VertexNormal Surface , V0 , VertexN[V[0].T[2]].NX , VertexN[V[0].T[2]].NY , VertexN[V[0].T[2]].NZ
								VertexNormal Surface , V1 , VertexN[V[i2-1].T[2]].NX , VertexN[V[i2-1].T[2]].NY , VertexN[V[i2-1].T[2]].NZ
								VertexNormal Surface , V2 , VertexN[V[i2].T[2]].NX , VertexN[V[i2].T[2]].NY , VertexN[V[i2].T[2]].NZ
								EndIf
								
								If VertexT[0] <> Null
								VertexTexCoords Surface , V0 , VertexT[V[0].T[1]].U ,1- VertexT[V[0].T[1]].V
								VertexTexCoords Surface , V1 , VertexT[V[i2-1].T[1]].U ,1- VertexT[V[i2-1].T[1]].V
								VertexTexCoords Surface , V2 , VertexT[V[i2].T[1]].U , 1 - VertexT[V[i2].T[1]].V
		 						EndIf
							
								AddTriangle Surface , V0 , V2 , V1
							Next
							

						
						FC:+1
					EndIf
				EndIf	
						
			EndIf
		EndIf
	Wend
	DebugLog "VertexCount : " + VC
	DebugLog "NormalsCount : " + VN
	DebugLog "TexCoordsCount : " + VT
	DebugLog "Faces : " + FC
	DebugLog "Surfs : " + SC
	DebugLog "surfs real : " + CountSurfaces(Mesh) 
	
	For Local V:TObjMtl = EachIn MatLibs.Values()
		Print V.Name
	Next
	
	CloseStream(Stream)
	'FlipMesh Mesh
	UpdateNormals(Mesh)
	Return Mesh
End Function
Type TFaceData
	Field T:Int[3]
	Field its:Int
	
	Method GetValues:String(Data:String)
		'Print Data
		Local F:Int[3]
		For Local I:Int = 0 To 2
			'Print "Before : " + Data
			Local FL:Int = Data.Find("/")
			If I < 2 Then
				T[I] = Int(Data[..FL])-1
				Data = Data[FL+1..]
			Else
				T[i] = Int(Data[..Data.Find(" ")])-1
			EndIf
			'Print "After : " + Data
		Next
		'Print Data		
		Return Data[Data.Find(" ")..]	
	End Method
End Type

Function ParseFaces:TFaceData[](Data:String) 
	Local Data1:String[] = Data.Split(" ")
	
	Local S:Int = 0
	If Data1[0] = "" Then S = 1
	Local FData:TFaceData[Data1.Length-S]
	
	For Local I:Int = S To Data1.Length - 1
		FData[I-S] = New TFaceData
		Local D2:String[] = Data1[I].Split("/") 
		'DebugLog "~q"+D2[1]+"~q" 
		FData[I-S].T[0] = Int(D2[0])-1 
		FData[I-S].T[1] = Int(D2[1])-1 
		FData[I-S].T[2] = Int(D2[2])-1 
	Next
	Return FData
End Function
	
Type TObjNormal
	Field NX# , NY# , NZ#
	
	Method GetValues(Data:String) 		
		Local F:Float[3]
		For Local I:Int = 0 To 2
			'Print "Before : " + Data
			Local FL:Int = Data.Find(" ")
			If I < 2 Then
				f[I] = Float(Data[..FL])
			Else
				f[i] = Float(Data) 
			EndIf
			Data = Data[FL+1..]
			'Print "After : " + Data
		Next
		NX = F[0]
		NY = F[1]
		NZ = F[2]
		'DebugLog ("X:"+X+" Y:"+Y + " Z:"+Z)
		
	End Method
End Type

Type TObjTexCoord
	Field U# , v#
	
	Method GetValues(Data:String)
		'DebugLog "OrigUV : " + Data
		Local F:Float[2]
		For Local I:Int = 0 To 1
			'Print "Before : " + Data
			Local FL:Int = Data.Find(" ")
			If I < 1 Then
				f[I] = Float(Data[..FL])
			Else
				f[i] = Float(Data) 
			EndIf
			Data = Data[FL+1..]
			'Print "After : " + Data
		Next
		u = F[0]
		v = F[1]
		'DebugLog ("X:"+U+" Y:"+V)
	End Method	
End Type	

Type TObjVertex
	Field X# , Y# , Z#
	'Field NX# , NY# , NZ#
	'Field u# , v#
	
	Method GetValues(Data:String) 
			Local F:Float[3]
			For Local I:Int = 0 To 2
				'Print "Before : " + Data
				Local FL:Int = Data.Find(" ")
				If I < 2 Then
					f[I] = Float(Data[..FL])
				Else
					f[i] = Float(Data) 
				EndIf
				Data = Data[FL+1..]
				'Print "After : " + Data
			Next
			X = F[0]
			Y = F[1]
			Z = F[2]
			'DebugLog ("X:"+X+" Y:"+Y + " Z:"+Z)		
	End Method	
End Type

Type TObjMTL
	Field name:String
	Field Brush:TBrush
	Field Texture:TTexture
End Type

Function ParseMTLLib:TObjMTL[](Path:String)
	Local matStream:TStream = ReadStream(Path) 
	Local dir:String = ExtractDir(Path) + "/"
	If dir = "/" Then dir = ""
	If Not matStream Then Return Null
	Local MatLib:TObjMtl[0]
	Local CMI:Int = -1
	While Not Eof(matStream)
		Local Line:String = ReadLine(MatStream) 
		If Line[0..7] = "newmtl " Then
			MatLib = MatLib[..Matlib.Length + 1]
			CMI = MatLib.Length-1
			MatLib[CMI] = New TObjMtl
			MatLib[CMI].Name = Line[7..].Trim() 
			MatLib[CMI].Brush = CreateBrush() 
			BrushFX MatLib[CMI].Brush,4+16
			DebugLog("Matname : " + Matlib[CMI].Name)
		EndIf
		'Colours
		If Line[0..3] = "Kd " Then
			Local Data:String = Line[3..].Trim()+" "
			Local F:Float[3]
			For Local I:Int = 0 To 2
				'Print "Before : " + Data
				Local FL:Int = Data.Find(" ")
				If I < 2 Then
					f[I] = Float(Data[..FL])
				Else
					f[i] = Float(Data) 
				EndIf
				Data = Data[FL+1..]
				'Print "After : " + Data
			Next
			BrushColor(MatLib[CMI].Brush , F[0] * 255 , F[1] * 255 , F[2] * 255) 
			DebugLog("MatColor : " +  (F[0] * 255) +","+(F[1] * 255)+","+(F[2] * 255))
		EndIf
		
		If Line[0..2] = "d " Then
			'BrushAlpha(MatLib[CMI].Brush , Float(Line[2..]))
			DebugLog("MatAlpha : " + Float(Line[2..]) ) 
		EndIf
		
		If Line[0..3] = "Tr " Then
			'BrushAlpha(MatLib[CMI].Brush , Float(Line[2..])) 
			DebugLog("MatAlpha : " + Float(Line[2..]) ) 
		EndIf 
		
		If Line[0..7] = "map_Kd " Then
			MatLib[CMI].Texture = LoadTexture(dir+Line[7..].Trim(),4) 
			If MatLib[CMI].Texture <> Null BrushTexture(MatLib[CMI].Brush , MatLib[CMI].Texture) 
			DebugLog("MatTexture : " + Line[7..].Trim() ) 
		EndIf
	Wend
	
	Return MatLib
End Function

Comments

AdamRedwoods

2011

Love it, thanks! Works with Lightwave9 and 3DCoat.

One small problem tho in Lightwave 9, it seems it does not always export texture vertex numbers, leaving a "f 41//32..." strange, but it drops out with an undefined array error.

Easy fix, just check for negative vertex numbers. I assigned to vertex 0, maybe not the best but it handles fine for what I need. THE PROBLEM: some OBJ files use negative vertex numbers to move back up the vertex list.

Function ParseFaces:TFaceData[](Data:String) 
	Local Data1:String[] = Data.Split(" ")
	
	Local S:Int = 0
	If Data1[0] = "" Then S = 1
	Local FData:TFaceData[Data1.Length-S]
	
	For Local I:Int = S To Data1.Length - 1
		FData[I-S] = New TFaceData
		Local D2:String[] = Data1[I].Split("/") 
		'DebugLog "~q"+D2[1]+"~q" 
		FData[I-S].T[0] = Int(D2[0])-1 
		FData[I-S].T[1] = Int(D2[1])-1 
		FData[I-S].T[2] = Int(D2[2])-1

		If FData[I-S].T[0] <0 Then  FData[I-S].T[0]=0
		If FData[I-S].T[1] <0 Then  FData[I-S].T[1]=0
		If FData[I-S].T[2] <0 Then  FData[I-S].T[2]=0
	Next
	Return FData
End Function

Also found an error:

If Line[0..2].toLower() = "g " Then GName = Line[2..].toLower()

Another error with "s" but I've also taken the liberty to create a surface cache to consolidate the surfaces, since Lightwave will separate the surfaces.

add this before the While not EOF stream:

Local surfaceCache:Int[] = New Int[255]

then

If Line[0..2].toLower() = "s " Then
						 snumber = Int(Line[2..])
						Local sstrue:Int =False
						For Local ss:Int = 0 To SC
							If surfaceCache[ss] = snumber Then sstrue=True
						Next
						If Not sstrue 
							 Surface = CreateSurface(Mesh)
							' EntityFX Mesh,16
							surfaceCache[SC] = snumber
							SC:+1 
							'' "new surface"
						Else
							Surface = GetSurface(Mesh,snumber)
							'' "old surface "	
						EndIf
				EndIf

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