Please test this

Graphics3D 800, 600
SetBuffer BackBuffer()

Cam = CreateCamera()
MoveEntity Cam, 0, 0, -10

Mesh = CreateMesh()
Surf = CreateSurface(Mesh)

For i = 1 To 500
	V = CreateQuadVerts%(Surf)
	CreateQuadTris%(Surf, V)
Next
	
While Not KeyHit(1)

	RenderWorld()

	Framecounter_counter=Framecounter_counter+1
	If Framecounter_time=0 Then Framecounter_time=MilliSecs()
	If Framecounter_time+1001< MilliSecs() Then
		Framecounter_framerate=Framecounter_counter
		Framecounter_counter=0
		Framecounter_time=MilliSecs()
	EndIf

	Text 10,10,"fps: "+Framecounter_framerate
	
	Flip False
Wend

Function CreateQuadVerts%(Surf%)

	If Surf = 0 Then Return ;ERROR CHECK

	;Top left vert
	v1 = AddVertex(Surf, -.5, .5, 0, 0, 0)
	;Top right Vert
	AddVertex(Surf, .5, .5, 0, 1, 0)
	;Bottom left vert
	AddVertex(Surf, -.5, -.5, 0, 0, 1)
	;Bottom right vert
	AddVertex(Surf, .5, -.5, 0, 1, 1)
	Return v1
	
End Function


Function CreateQuadTris%(Surf%, Vert%)

	t1 = AddTriangle(Surf, Vert, Vert+1, Vert+2)
	t2 = AddTriangle(Surf, Vert+2, Vert+1, Vert+3)

	Return t1
	
End Function