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using System;
using System.Collections.Generic;
using System.Linq;
using Rhino;
using Rhino.Commands;
using Rhino.Geometry;
using Rhino.Geometry.Intersect;
using Rhino.Input;
using Rhino.Input.Custom;
using Rhino.DocObjects;
namespace examples_cs
{
public class FurthestZOnSurfaceCommand : Command
{
public override string EnglishName { get { return "csFurthestZOnSurfaceGivenXY"; } }
protected override Result RunCommand(RhinoDoc doc, RunMode mode)
{
#region user input
// select a surface
var gs = new GetObject();
gs.SetCommandPrompt("select surface");
gs.GeometryFilter = ObjectType.Surface;
gs.DisablePreSelect();
gs.SubObjectSelect = false;
gs.Get();
if (gs.CommandResult() != Result.Success)
return gs.CommandResult();
// get the brep
var brep = gs.Object(0).Brep();
if (brep == null)
return Result.Failure;
// get X and Y
double x = 0.0, y = 0.0;
var rc = RhinoGet.GetNumber("value of X coordinate", true, ref x);
if (rc != Result.Success)
return rc;
rc = RhinoGet.GetNumber("value of Y coordinate", true, ref y);
if (rc != Result.Success)
return rc;
#endregion
// an earlier version of this sample used a curve-brep intersection to find Z
//var maxZ = maxZIntersectionMethod(brep, x, y, doc.ModelAbsoluteTolerance);
// projecting points is another way to find Z
var max_z = MaxZProjectionMethod(brep, x, y, doc.ModelAbsoluteTolerance);
if (max_z != null)
{
RhinoApp.WriteLine("Maximum surface Z coordinate at X={0}, Y={1} is {2}", x, y, max_z);
doc.Objects.AddPoint(new Point3d(x, y, max_z.Value));
doc.Views.Redraw();
}
else
RhinoApp.WriteLine("no maximum surface Z coordinate at X={0}, Y={1} found.", x, y);
return Result.Success;
}
private static double? MaxZProjectionMethod(Brep brep, double x, double y, double tolerance)
{
double? max_z = null;
var breps = new List<Brep> {brep};
var points = new List<Point3d> {new Point3d(x, y, 0)};
// grab all the points projected in Z dir. Aggregate finds furthest Z from XY plane
try {
max_z = (from pt in Intersection.ProjectPointsToBreps(breps, points, new Vector3d(0, 0, 1), tolerance) select pt.Z)
// Here you might be tempted to use .Max() to get the largest Z value but that doesn't work because
// Z might be negative. This custom aggregate returns the max Z independant of the sign. If it had a name
// it could be MaxAbs()
.Aggregate((z1, z2) => Math.Abs(z1) > Math.Abs(z2) ? z1 : z2);
} catch (InvalidOperationException) {/*Sequence contains no elements*/}
return max_z;
}
private double? MaxZIntersectionMethod(Brep brep, double x, double y, double tolerance)
{
double? max_z = null;
var bbox = brep.GetBoundingBox(true);
var max_dist_from_xy = (from corner in bbox.GetCorners() select corner.Z)
// furthest Z from XY plane.
// Here you might be tempted to use .Max() to get the largest Z value but that doesn't work because
// Z might be negative. This custom aggregate returns the max Z independant of the sign. If it had a name
// it could be MaxAbs()
.Aggregate((z1, z2) => Math.Abs(z1) > Math.Abs(z2) ? z1 : z2);
// multiply distance by 2 to make sure line intersects completely
var line_curve = new LineCurve(new Point3d(x, y, 0), new Point3d(x, y, max_dist_from_xy*2));
Curve[] overlap_curves;
Point3d[] inter_points;
if (Intersection.CurveBrep(line_curve, brep, tolerance, out overlap_curves, out inter_points))
{
if (overlap_curves.Length > 0 || inter_points.Length > 0)
{
// grab all the points resulting frem the intersection.
// 1st set: points from overlapping curves,
// 2nd set: points when there was no overlap
// .Aggregate: furthest Z from XY plane.
max_z = (from c in overlap_curves select Math.Abs(c.PointAtEnd.Z) > Math.Abs(c.PointAtStart.Z) ? c.PointAtEnd.Z : c.PointAtStart.Z)
.Union
(from p in inter_points select p.Z)
// Here you might be tempted to use .Max() to get the largest Z value but that doesn't work because
// Z might be negative. This custom aggregate returns the max Z independant of the sign. If it had a name
// it could be MaxAbs()
.Aggregate((z1, z2) => Math.Abs(z1) > Math.Abs(z2) ? z1 : z2);
}
}
return max_z;
}
}
}