kindred/create
1
1
Fork 0
Code Issues 37 Pull Requests Actions Packages Projects 9 Releases 2 Wiki Activity

Sketcher: BSpline simplified endpoint tangency/perpendicularity solver implementation

Browse Source 
=====================================================================================

Support for tangency/perpendicularity using angle via point for BSpline with appropriate
endpoint multiplicity so that the endpoints goes thru the first and last poles (control points).

Warning: Not applicable to periodic BSplines.
Warning: Not applicable to any non-periodic BSpline with inappropriate endpoint conditions.
This commit is contained in:
Abdullah Tahiri
2017-01-14 23:29:32 +01:00
parent 9bf1e8f4f4
commit e53dc90c9a
2 changed files with 58 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

44
src/Mod/Sketcher/App/planegcs/Geo.cpp
View File

@@ -611,7 +611,49 @@ ArcOfParabola* ArcOfParabola::Copy()
DeriVector2 BSpline::CalculateNormal(Point& p, double* derivparam)
{
// place holder
DeriVector2 ret = DeriVector2();
DeriVector2 ret;
if (mult[0] > degree && mult[mult.size()-1] > degree) {
// if endpoints thru end poles
if(*p.x == *start.x && *p.y == *start.y) {
// and you are asking about the normal at start point
// then tangency is defined by first to second poles
DeriVector2 endpt(this->poles[1], derivparam);
DeriVector2 spt(this->poles[0], derivparam);
DeriVector2 npt(this->poles[2], derivparam); // next pole to decide normal direction
DeriVector2 tg = endpt.subtr(spt);
DeriVector2 nv = npt.subtr(spt);
if ( tg.scalarProd(nv) > 0 )
ret = tg.rotate90cw();
else
ret = tg.rotate90ccw();
}
else if(*p.x == *end.x && *p.y == *end.y) {
// and you are asking about the normal at end point
// then tangency is defined by last to last but one poles
DeriVector2 endpt(this->poles[poles.size()-1], derivparam);
DeriVector2 spt(this->poles[poles.size()-2], derivparam);
DeriVector2 npt(this->poles[poles.size()-3], derivparam); // next pole to decide normal direction
DeriVector2 tg = endpt.subtr(spt);
DeriVector2 nv = npt.subtr(spt);
if ( tg.scalarProd(nv) > 0 )
ret = tg.rotate90ccw();
else
ret = tg.rotate90cw();
} else {
// another point and we have no clue until we implement De Boor
ret = DeriVector2();
}
}
else {
// either periodic or abnormal endpoint multiplicity, we have no clue so currently unsupported
ret = DeriVector2();
}
return ret;
}