Flip Mesh

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Ross C

Ok, i knocked this up. It should do what you want it to. I've not tried it on any complex meshes, but it works on primates. All you need to do, is copy the function into your code, and call it. You must pass across a mesh and a plane you wish to mirror along. 0 = x, 1 = y and 2 = z.

Also, if you have a surface you wish to mirror, you can pass that across. If not, omit it, and the function will mirror all surfaces.

Open in online IDE

Graphics3D 800,600
SetBuffer BackBuffer()


Global cam = CreateCamera()
PositionEntity cam,0,0,-10

Global light = CreateLight()

Global cube = CreateCube()
PositionMesh cube,2,1,2


While Not KeyHit(1)


	If KeyHit(203) Then mirror_mesh(cube,0)
	If KeyHit(200) Then mirror_mesh(cube,1)
	If KeyHit(208) Then mirror_mesh(cube,2)


	UpdateWorld
	RenderWorld
	Flip
Wend
End




Function mirror_mesh(mesh,plane,surface = 0)


	If plane < 0 Or plane > 2 Then Return 0

	If surface = 0 Then
		s_count = CountSurfaces(mesh)
		l_count = 1
	Else
		For loop = 0 To CountSurfaces(mesh)
			temp = GetSurface(mesh,loop)
			If surface = temp Then
				s_count = temp
				l_count = temp
			End If
		Next
	End If
	
	average_x# = EntityX(mesh) - (MeshWidth(mesh)/2.0)
	average_y# = EntityY(mesh) - (MeshHeight(mesh)/2.0)
	average_z# = EntityZ(mesh) - (MeshDepth(mesh)/2.0)


	If plane = 0 Then
		For sloop = l_count To s_count
			surface = GetSurface(mesh,sloop)
			For loop = 0 To CountVertices(surface) - 1

				ny# = VertexNY (surface,loop)
				nz# = VertexNZ (surface,loop)
				nx# = VertexNX (surface,loop)
				VertexCoords surface,loop, average_x - ( average_x + VertexX(surface,loop)), VertexY(surface,loop), VertexZ(surface,loop)
				VertexNormal surface,loop,nx,ny,-nz
			Next
		Next
	ElseIf plane = 1 Then
		For sloop = l_count To s_count
			surface = GetSurface(mesh,sloop)
			For loop = 0 To CountVertices(surface) - 1

				ny# = VertexNY (surface,loop)
				nz# = VertexNZ (surface,loop)
				nx# = VertexNX (surface,loop)

				VertexCoords surface,loop, VertexX(surface,loop), average_y - ( average_y + VertexY(surface,loop)), VertexZ(surface,loop)
				VertexNormal surface,loop,-nx,ny,-nz
			Next
		Next
	ElseIf plane = 2 Then
		For sloop = l_count To s_count
			surface = GetSurface(mesh,sloop)
			For loop = 0 To CountVertices(surface) - 1

				ny# = VertexNY (surface,loop)
				nz# = VertexNZ (surface,loop)
				nx# = VertexNX (surface,loop)

				VertexCoords surface,loop, VertexX(surface,loop), VertexY(surface,loop),  average_z - ( average_z + VertexZ(surface,loop))
				VertexNormal surface,loop,-nx,ny,nz
			Next
		Next
	End If

	FlipMesh mesh
	
End Function