///<summary>
/// Get the centroid of a Region.
///</summary>
///<param name="cur">An optional curve used to define the region.</param>
///<returns>A nullable Point3d containing the centroid of the Region.</returns>
public static _AcGe.Point3d? GetCentroid(this _AcDb.Region reg, _AcDb.Curve cur = null)
{
if (cur == null)
{
var idc = new _AcDb.DBObjectCollection();
reg.Explode(idc);
if (idc.Count == 0)
{
return(null);
}
cur = idc[0] as _AcDb.Curve;
}
if (cur == null)
{
return(null);
}
var cs = cur.GetPlane().GetCoordinateSystem();
var o = cs.Origin;
var x = cs.Xaxis;
var y = cs.Yaxis;
var a = reg.AreaProperties(ref o, ref x, ref y);
var pl = new _AcGe.Plane(o, x, y);
return(pl.EvaluatePoint(a.Centroid));
}
static public Plane ToRhino(this _OdGe.Plane plane)
{
var coordSystem = plane.GetCoordinateSystem();
return(new Plane(coordSystem.Origin.ToRhino(),
coordSystem.Xaxis.ToRhino(),
coordSystem.Yaxis.ToRhino()));
}
// DBText extensions
///<summary>
/// Gets the bounds of a DBText object.
///</summary>
///<param name="fac">Optional multiplier to increase/reduce buffer.</param>
///<returns>A collection of points defining the text's extents.</returns>
public static _AcGe.Point3dCollection ExtractBounds(
this _AcDb.DBText txt, double fac = 1.0
)
{
var pts = new _AcGe.Point3dCollection();
if (txt.Bounds.HasValue && txt.Visible)
{
// Create a straight version of the text object
// and copy across all the relevant properties
// (stopped copying AlignmentPoint, as it would
// sometimes cause an eNotApplicable error)
// We'll create the text at the WCS origin
// with no rotation, so it's easier to use its
// extents
var txt2 = new _AcDb.DBText();
txt2.Normal = _AcGe.Vector3d.ZAxis;
txt2.Position = _AcGe.Point3d.Origin;
// Other properties are copied from the original
txt2.TextString = txt.TextString;
txt2.TextStyleId = txt.TextStyleId;
txt2.LineWeight = txt.LineWeight;
txt2.Thickness = txt2.Thickness;
txt2.HorizontalMode = txt.HorizontalMode;
txt2.VerticalMode = txt.VerticalMode;
txt2.WidthFactor = txt.WidthFactor;
txt2.Height = txt.Height;
txt2.IsMirroredInX = txt2.IsMirroredInX;
txt2.IsMirroredInY = txt2.IsMirroredInY;
txt2.Oblique = txt.Oblique;
// Get its bounds if it has them defined
// (which it should, as the original did)
if (txt2.Bounds.HasValue)
{
var maxPt = txt2.Bounds.Value.MaxPoint;
// Only worry about this single case, for now
_AcGe.Matrix3d mat = _AcGe.Matrix3d.Identity;
if (txt.Justify == _AcDb.AttachmentPoint.MiddleCenter)
{
mat = _AcGe.Matrix3d.Displacement((_AcGe.Point3d.Origin - maxPt) * 0.5);
}
// Place all four corners of the bounding box
// in an array
double minX, minY, maxX, maxY;
if (txt.Justify == _AcDb.AttachmentPoint.MiddleCenter)
{
minX = -maxPt.X * 0.5 * fac;
maxX = maxPt.X * 0.5 * fac;
minY = -maxPt.Y * 0.5 * fac;
maxY = maxPt.Y * 0.5 * fac;
}
else
{
minX = 0;
minY = 0;
maxX = maxPt.X * fac;
maxY = maxPt.Y * fac;
}
var bounds =
new _AcGe.Point2d[] {
new _AcGe.Point2d(minX, minY),
new _AcGe.Point2d(minX, maxY),
new _AcGe.Point2d(maxX, maxY),
new _AcGe.Point2d(maxX, minY)
};
// We're going to get each point's WCS coordinates
// using the plane the text is on
var pl = new _AcGe.Plane(txt.Position, txt.Normal);
// Rotate each point and add its WCS location to the
// collection
foreach (_AcGe.Point2d pt in bounds)
{
pts.Add(
pl.EvaluatePoint(
pt.RotateBy(txt.Rotation, _AcGe.Point2d.Origin)
)
);
}
}
}
return(pts);
}
///<summary>
/// Projects the provided Point3d onto the specified coordinate system.
///</summary>
///<param name="ucs">The coordinate system to project onto.</param>
///<returns>A Point2d projection on the plane of the
/// coordinate system.</returns>
public static _AcGe.Point2d ProjectToUcs(this _AcGe.Point3d pt, _AcGe.CoordinateSystem3d ucs)
{
var pl = new _AcGe.Plane(ucs.Origin, ucs.Zaxis);
return(pl.ParameterOf(pt));
}
