ON_2dVector ON_Ellipse::GradientAt(
const ON_2dPoint& p // coordinates in plane
) const
{
ON_2dVector g;
if ( radius[0] != 0.0 && radius[1] != 0.0 ) {
g.x = 2.0*p.x/(radius[0]*radius[0]);
g.y = 2.0*p.y/(radius[1]*radius[1]);
}
else {
g.Zero();
}
return g;
}
ON_2dVector ON_Circle::GradientAt(
const ON_2dPoint& p // coordinates in plane
) const
{
ON_2dVector g;
if ( radius != 0.0 ) {
const double rr = 2.0/(radius*radius);
g.x = rr*p.x;
g.y = rr*p.y;
}
else {
g.Zero();
}
return g;
}
unsigned
NurbsTools::getClosestPoint (const ON_2dPoint &p, const ON_2dVector &dir, const vector_vec2d &data,
unsigned &idxcp)
{
if (data.empty ())
throw std::runtime_error ("[NurbsTools::getClosestPoint(2d)] Data empty.\n");
unsigned idx (0);
idxcp = 0;
double dist2 (0.0);
double dist2cp (DBL_MAX);
for (unsigned i = 0; i < data.size (); i++)
{
ON_2dVector v = (data[i] - p);
double d2 = ON_DotProduct(v, v);
if (d2 < dist2cp)
{
idxcp = i;
dist2cp = d2;
}
if (NEAR_ZERO(d2, SMALL_FASTF))
return i;
v.Unitize();
double d1 = ON_DotProduct(dir, v);
if (d1 / d2 > dist2)
{
idx = i;
dist2 = d1 / d2;
}
}
return idx;
}
CRhinoCommand::result CCommandSampleIntepCrvOnSrf::RunCommand( const CRhinoCommandContext& context )
{
CRhinoGetObject go;
go.SetCommandPrompt( L"Select surface to draw curve on" );
go.SetGeometryFilter( CRhinoObject::surface_object);
go.GetObjects( 1, 1 );
if( go.CommandResult() != CRhinoCommand::success )
return go.CommandResult();
const CRhinoObject* obj = go.Object(0).Object();
const ON_BrepFace* face = go.Object(0).Face();
if( 0 == obj || 0 == face )
return CRhinoCommand::failure;
ON_SimpleArray<ON_2dPoint> points2d(25);
CRhinoGetPoint gp;
gp.Constrain( *face, obj->Attributes().m_wire_density );
for(;;)
{
gp.ClearCommandOptions();
if( points2d.Count() < 1 )
gp.SetCommandPrompt( L"Start of curve" );
else if( points2d.Count() == 1 )
gp.SetCommandPrompt( L"Next point" );
else
gp.SetCommandPrompt( L"Next point. Press Enter when done" );
gp.AcceptUndo( points2d.Count() > 0 );
gp.AcceptNothing();
CRhinoGet::result res = gp.GetPoint();
if( res == CRhinoGet::cancel)
return CRhinoCommand::cancel;
else if ( res == CRhinoGet::undo)
{
points2d.Remove(); // remove last point
continue;
}
else if( res == CRhinoGet::point)
{
ON_2dPoint pt;
if( gp.PointOnSurface(&pt.x, &pt.y) )
{
int count = points2d.Count();
if( count > 0 )
{
ON_2dVector v = *points2d.At(count-1) - pt;
if ( v.IsTiny())
continue;
}
points2d.Append( pt );
}
continue;
}
break;
}
const int count = points2d.Count();
if( count > 1)
{
// Check for closed curve
int is_closed = 0;
if( count > 3 )
{
ON_2dPoint pt = points2d[0];
if( pt.DistanceTo(points2d[count-1]) < ON_SQRT_EPSILON )
is_closed = 1;
}
double tol = context.m_doc.AbsoluteTolerance();
ON_Curve* crv = RhinoInterpolatePointsOnSurface( *face, points2d, is_closed, tol, 1 );
if( crv )
{
CRhinoCurveObject* crv_obj = new CRhinoCurveObject();
crv_obj->SetCurve( crv );
context.m_doc.AddObject( crv_obj );
context.m_doc.Redraw();
}
return CRhinoCommand::success;
}
return CRhinoCommand::success;
}
