Description This command sets the description string for a given surface roughness node.
Syntax SurfRoughSetDescription roughNode, roughDesc
Parameters roughNode As Long Node number of the surface roughness model being modified.
roughDesc As String String descriptor being set for roughNode.
Example The following example creates a surface roughness model with a Gaussian distribution according to a specified HWHM.
Sub Main
Dim numSamps As Long Dim hwhm As Double, maxAng As Double, overallProb As Double '---------------- 'USER INPUT '---------------- 'number of samples to use in the SRSN roughness model numSamps = 90 'maximum angular deviation for sample points in degrees maxAng = 1 'half-width half-max of the gaussian distribution in degrees hwhm = 0.175 'degrees 'probability of surface normal deviation occurring on intersection overallProb = 0.98 '---------------- 'Derived parameters Dim c As Double c = hwhm/Sqr(2*Log(2))
'Delete all existing sampled normal roughness models Dim roughCount As Long, curRough As Long For curRough = SurfRoughGetMaxNodeNum To 0 Step -1 If SurfRoughIsValidNode( curRough ) Then If SurfRoughGetType( curRough ) = "SampRanNorm" Then Print "Sampled random normal roughness model at node " & curRough & " deleted." SurfRoughDelete( curRough ) End If End If Next curRough
'Create a new sampled random surface normal (SRSN) roughness model Dim roughNode As Long roughNode = SurfRoughSRSNCreate( "Gaussian Roughness", "HWHM=" & CStr(hwhm) )
'Dynamically size the arrays for the SRSN sample entries Dim angles() As Double ReDim angles( numSamps ) Dim relProbs() As Double ReDim relProbs( numSamps ) Dim curSamp As Long
'Set entries for the gaussian SRSN model For curSamp = 0 To numSamps-1 'Assign angle and gaussian probability with sin(theta) correction factor 'Populate angle sample value If curSamp = 0 Then angles(curSamp) = 1e-6 Else angles(curSamp) = curSamp*(maxAng/(numSamps-1)) End If 'Populate probability value relProbs(curSamp) = Exp(-(angles(curSamp)/c)^2) relProbs(curSamp) = relProbs(curSamp)*Sin(DegToRad(angles(curSamp))) Next curSamp
'Set the entries to the surface roughness node SurfRoughSRSNSetEntries( roughNode, angles(), relProbs() )
'Set the overall probability for the roughness SurfRoughSRSNSetOverallRoughnessProbability( roughNode, overallProb )
'Set the descriptor string SurfRoughSetDescription( roughNode, "Gaussian with HWHM=" & Format$(hwhm,"#0.00") )
'Update the document Update
End Sub
See Also SurfRoughSRSNGetIthProbability SurfRoughSRSNGetOverallRoughnessProbability SurfRoughSRSNSetOverallRoughnessProbability
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