suzanne.soy/solvespace
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

DXF: export non-rational beziers as splines instead of pwl.

Browse Source
This commit is contained in:
EvilSpirit 2015-12-28 14:03:51 +06:00 committed by whitequark
parent c469af6600
commit 3fdfca10f6
1 changed files with 46 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
src/exportvector.cpp
View File

@ -62,6 +62,45 @@ public:
lv.Clear();
}
void makeKnotsFor(DRW_Spline *spline) {
// QCad/LibreCAD require this for some reason.
if(spline->degree == 3) {
spline->nknots = 8;
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(1.0);
spline->knotslist.push_back(1.0);
spline->knotslist.push_back(1.0);
spline->knotslist.push_back(1.0);
} else if(spline->degree == 2) {
spline->nknots = 6;
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(0.0);
spline->knotslist.push_back(1.0);
spline->knotslist.push_back(1.0);
spline->knotslist.push_back(1.0);
} else {
oops();
}
}
void writeSpline(SBezier *sb) {
bool isRational = sb->IsRational();
DRW_Spline spline;
spline.flags = (isRational) ? 0x04 : 0x08;
spline.degree = sb->deg;
spline.ncontrol = sb->deg + 1;
makeKnotsFor(&spline);
for(int i = 0; i <= sb->deg; i++) {
spline.controllist.push_back(new DRW_Coord(sb->ctrl[i].x, sb->ctrl[i].y, 0.0));
if(isRational) spline.weightlist.push_back(sb->weight[i]);
}
dxf->writeSpline(&spline);
}
void writeBezier(SBezier *sb) {
Vector c;
Vector n = Vector::From(0.0, 0.0, 1.0);
@ -78,9 +117,15 @@ public:
if(dtheta < 0.0) swap(theta0, theta1);
writeArc(c, r, theta0, theta1);
} else if(sb->IsRational()) {
// Rational bezier
// We'd like to export rational beziers exactly, but the resulting DXF
// files can only be read by AutoCAD; LibreCAD/QCad simply do not
// implement the feature. So, export as piecewise linear for compatiblity.
writeBezierAsPwl(sb);
} else {
// Any other curve
writeBezierAsPwl(sb);
writeSpline(sb);
}
}
};