The following sample code demonstrates how determine the maximum Z coordinate value of a surface or polysurface given some X,Y coordinate.
CRhinoCommand::result CCommandTest::RunCommand( const CRhinoCommandContext& context )
{
double x = 0.0, y = 0.0;
ON_wString sx, sy, sz;
// Pick a brep to evaluate
CRhinoGetObject go;
go.SetCommandPrompt( L"Select surface or polysurface to evaluate" );
go.SetGeometryFilter( CRhinoGetObject::surface_object|CRhinoGetObject::polysrf_object );
go.GetObjects( 1, 1 );
if( go.CommandResult() != success )
return go.CommandResult();
// Get the brep geometry
const CRhinoObjRef& ref = go.Object(0);
const ON_Brep* brep = ref.Brep();
if( !brep )
return failure;
// Prompt for an X coordinate value
CRhinoGetNumber gn;
gn.SetCommandPrompt( L"Value of X coordinate" );
gn.SetDefaultNumber( x );
gn.GetNumber();
if( gn.CommandResult() != success )
return gn.CommandResult();
x = gn.Number();
RhinoFormatNumber( x, sx );
// Prompt for a Y coordinate value
gn.SetCommandPrompt( L"Value of Y coordinate" );
gn.SetDefaultNumber( y );
gn.GetNumber();
if( gn.CommandResult() != success )
return gn.CommandResult();
y = gn.Number();
RhinoFormatNumber( y, sy );
// Now that we have all of the input, we want to intersect
// a line curve with the brep. To determine the magnitude of
// the line, we will first get the brep's bounding box.
ON_BoundingBox bbox;
if( !brep->GetTightBoundingBox(bbox) )
return failure;
// Calculate the height of the bounding box
ON_3dVector v = bbox.Corner(0,0,1) - bbox.Corner(0,0,0);
// Starting point of line
ON_3dPoint p0( x, y, 0.0 );
// Ending point of line. To make sure the line
// completely intersects the brep, we will double
// the height.
ON_3dPoint p1( x, y, v.Length() * 2 );
// Create the line curve
ON_LineCurve line( p0, p1 );
// Intersect the line with the brep
ON_SimpleArray<ON_Curve*> curves;
ON_3dPointArray points;
bool rc = RhinoCurveBrepIntersect( line, *brep, context.m_doc.AbsoluteTolerance(), curves, points );
if( false == rc || 0 == points.Count() )
{
RhinoApp().Print( L"No maximum surface Z coordinate at %s,%s found.\n", sx, sy );
return nothing;
}
// Because it is possible that our line might intersect
// the brep in more than one place, find the intersection
// point that is farthest from our input coordinate.
int i;
ON_3dPoint pt = p0;
for( i = 0; i < points.Count(); i++ )
{
if( p0.DistanceTo(points[i]) > p0.DistanceTo(pt) )
pt = points[i];
}
// Print results
RhinoFormatNumber( pt.z, sz );
RhinoApp().Print( L"Maximum surface Z coordinate at %s,%s is %s.\n", sx, sy, sz );
// Optional, add a point object
context.m_doc.AddPointObject( pt );
// Delete any overlap intersection curves that might have been calculated
for( i = 0; i < curves.Count(); i++ )
{
delete curves[i];
curves[i] = 0;
}
context.m_doc.Redraw();
return success;
}
public override IRhinoCommand.result RunCommand(IRhinoCommandContext context)
{
// Pick a brep to evaluate
MRhinoGetObject go = new MRhinoGetObject();
go.SetCommandPrompt( "Select surface or polysurface to evaluate" );
go.SetGeometryFilter( IRhinoGetObject.GEOMETRY_TYPE_FILTER.surface_object |
IRhinoGetObject.GEOMETRY_TYPE_FILTER.polysrf_object );
go.GetObjects( 1, 1 );
if( go.CommandResult() != IRhinoCommand.result.success )
return go.CommandResult();
// Get the brep geometry
IRhinoObjRef objref = go.Object(0);
IOnBrep brep = objref.Brep();
if( brep == null )
return IRhinoCommand.result.failure;
double x = 0.0, y = 0.0;
// Prompt for an X coordinate value
MRhinoGetNumber gn = new MRhinoGetNumber();
gn.SetCommandPrompt( "Value of X coordinate" );
gn.SetDefaultNumber( x );
gn.GetNumber();
if( gn.CommandResult() != IRhinoCommand.result.success )
return gn.CommandResult();
x = gn.Number();
string sx = "";
RhUtil.RhinoFormatNumber( x, ref sx);
// Prompt for a Y coordinate value
gn.SetCommandPrompt( "Value of Y coordinate" );
gn.SetDefaultNumber( y );
gn.GetNumber();
if( gn.CommandResult() != IRhinoCommand.result.success )
return gn.CommandResult();
y = gn.Number();
string sy = "";
RhUtil.RhinoFormatNumber( y, ref sy );
// Now that we have all of the input, we want to intersect
// a line curve with the brep. To determine the magnitude of
// the line, we will first get the brep's bounding box.
OnBoundingBox bbox = new OnBoundingBox();
if( !brep.GetTightBoundingBox( ref bbox) )
return IRhinoCommand.result.failure;
// Calculate the height of the bounding box
On3dVector v = bbox.Corner(0,0,1) - bbox.Corner(0,0,0);
// Starting point of line
On3dPoint p0 = new On3dPoint( x, y, 0.0 );
// Ending point of line. To make sure the line completely
// intersects the brep, we will double the height.
On3dPoint p1 = new On3dPoint( x, y, v.Length() * 2 );
// Create the line curve
OnLineCurve line = new OnLineCurve( p0, p1 );
// Intersect the line with the brep
OnCurve[] curves = null;
On3dPointArray points = null;
bool rc = RhUtil.RhinoCurveBrepIntersect( line, brep,
context.m_doc.AbsoluteTolerance(), out curves, out points);
if( false == rc || points == null || points.Count() == 0 )
{
string msg = string.Format("No maximum surface Z coordinate at {0},{1} found.\n", sx, sy );
RhUtil.RhinoApp().Print( msg );
return IRhinoCommand.result.nothing;
}
// Because it is possible that our line might intersect
// the brep in more than one place, find the intersection
// point that is farthest from our input coordinate.
On3dPoint pt = new On3dPoint(p0);
for( int i = 0; i < points.Count(); i++ )
{
On3dPoint testPt = points[i];
if( p0.DistanceTo(testPt) > p0.DistanceTo(pt) )
pt.Set(testPt.x, testPt.y, testPt.z );
}
// Print results
string sz = "";
RhUtil.RhinoFormatNumber( pt.z, ref sz );
string msg2 = string.Format("Maximum surface Z coordinate at {0},{1} is {2}.\n", sx, sy, sz);
RhUtil.RhinoApp().Print( msg2 );
// Optional, add a point object
context.m_doc.AddPointObject( pt );
context.m_doc.Redraw();
return IRhinoCommand.result.success;
}
Public Overrides Function RunCommand(ByVal context As RMA.Rhino.IRhinoCommandContext) _
As RMA.Rhino.IRhinoCommand.result
' Pick a brep to evaluate
Dim go As New MRhinoGetObject()
go.SetCommandPrompt("Select surface or polysurface to evaluate")
go.SetGeometryFilter(IRhinoGetObject.GEOMETRY_TYPE_FILTER.surface_object Or _
IRhinoGetObject.GEOMETRY_TYPE_FILTER.polysrf_object)
go.GetObjects(1, 1)
If (go.CommandResult() <> IRhinoCommand.result.success) Then
Return go.CommandResult()
End If
' Get the brep geometry
Dim objref As IRhinoObjRef = go.Object(0)
Dim brep As IOnBrep = objref.Brep()
If (brep Is Nothing) Then
Return IRhinoCommand.result.failure
End If
Dim x As Double = 0.0, y As Double = 0.0
' Prompt for an X coordinate value
Dim gn As New MRhinoGetNumber()
gn.SetCommandPrompt("Value of X coordinate")
gn.SetDefaultNumber(x)
gn.GetNumber()
If (gn.CommandResult() <> IRhinoCommand.result.success) Then
Return gn.CommandResult()
End If
x = gn.Number()
Dim sx As String = ""
RhUtil.RhinoFormatNumber(x, sx)
' Prompt for a Y coordinate value
gn.SetCommandPrompt("Value of Y coordinate")
gn.SetDefaultNumber(y)
gn.GetNumber()
If (gn.CommandResult() <> IRhinoCommand.result.success) Then
Return gn.CommandResult()
End If
y = gn.Number()
Dim sy As String = ""
RhUtil.RhinoFormatNumber(y, sy)
' Now that we have all of the input, we want to intersect
' a line curve with the brep. To determine the magnitude of
' the line, we will first get the brep's bounding box.
Dim bbox As New OnBoundingBox()
If (Not brep.GetTightBoundingBox(bbox)) Then
Return IRhinoCommand.result.failure
End If
' Calculate the height of the bounding box
Dim v As On3dVector = bbox.Corner(0, 0, 1) - bbox.Corner(0, 0, 0)
' Starting point of line
Dim p0 As New On3dPoint(x, y, 0.0)
' Ending point of line. To make sure the line completely
' intersects the brep, we will double the height.
Dim p1 As New On3dPoint(x, y, v.Length() * 2)
' Create the line curve
Dim line As New OnLineCurve(p0, p1)
' Intersect the line with the brep
Dim curves() As OnCurve = Nothing
Dim points As On3dPointArray = Nothing
Dim rc As Boolean = RhUtil.RhinoCurveBrepIntersect(line, brep, _
context.m_doc.AbsoluteTolerance(), curves, points)
If (False = rc OrElse points Is Nothing OrElse points.Count() = 0) Then
Dim msg As String = String.Format("No maximum surface Z coordinate at {0},{1} found.\n", sx, sy)
RhUtil.RhinoApp().Print(msg)
Return IRhinoCommand.result.nothing
End If
' Because it is possible that our line might intersect
' the brep in more than one place, find the intersection
' point that is farthest from our input coordinate.
Dim pt As New On3dPoint(p0)
For i As Integer = 0 To points.Count - 1
Dim testPt As On3dPoint = points(i)
If (p0.DistanceTo(testPt) > p0.DistanceTo(pt)) Then
pt.Set(testPt.x, testPt.y, testPt.z)
End If
Next
' Print results
Dim sz As String = ""
RhUtil.RhinoFormatNumber(pt.z, sz)
Dim msg2 As String = String.Format("Maximum surface Z coordinate at {0},{1} is {2}.\n", sx, sy, sz)
RhUtil.RhinoApp().Print(msg2)
' Optional, add a point object
context.m_doc.AddPointObject(pt)
context.m_doc.Redraw()
Return IRhinoCommand.result.success
End Function