void SShell::MakeFromRevolutionOf(SBezierLoopSet *sbls, Vector pt, Vector axis, RgbaColor color, Group *group)
{
SBezierLoop *sbl;
int i0 = surface.n, i;
// Normalize the axis direction so that the direction of revolution
// ends up parallel to the normal of the sketch, on the side of the
// axis where the sketch is.
Vector pto;
double md = VERY_NEGATIVE;
for(sbl = sbls->l.First(); sbl; sbl = sbls->l.NextAfter(sbl)) {
SBezier *sb;
for(sb = sbl->l.First(); sb; sb = sbl->l.NextAfter(sb)) {
// Choose the point farthest from the axis; we'll get garbage
// if we choose a point that lies on the axis, for example.
// (And our surface will be self-intersecting if the sketch
// spans the axis, so don't worry about that.)
Vector p = sb->Start();
double d = p.DistanceToLine(pt, axis);
if(d > md) {
md = d;
pto = p;
}
}
}
Vector ptc = pto.ClosestPointOnLine(pt, axis),
up = (pto.Minus(ptc)).WithMagnitude(1),
vp = (sbls->normal).Cross(up);
if(vp.Dot(axis) < 0) {
axis = axis.ScaledBy(-1);
}
// Now we actually build and trim the surfaces.
for(sbl = sbls->l.First(); sbl; sbl = sbls->l.NextAfter(sbl)) {
int i, j;
SBezier *sb, *prev;
List<Revolved> hsl = {};
for(sb = sbl->l.First(); sb; sb = sbl->l.NextAfter(sb)) {
Revolved revs;
for(j = 0; j < 4; j++) {
if(sb->deg == 1 &&
(sb->ctrl[0]).DistanceToLine(pt, axis) < LENGTH_EPS &&
(sb->ctrl[1]).DistanceToLine(pt, axis) < LENGTH_EPS)
{
// This is a line on the axis of revolution; it does
// not contribute a surface.
revs.d[j].v = 0;
} else {
SSurface ss = SSurface::FromRevolutionOf(sb, pt, axis,
(PI/2)*j,
(PI/2)*(j+1));
ss.color = color;
if(sb->entity != 0) {
hEntity he;
he.v = sb->entity;
hEntity hface = group->Remap(he, Group::REMAP_LINE_TO_FACE);
if(SK.entity.FindByIdNoOops(hface) != NULL) {
ss.face = hface.v;
}
}
revs.d[j] = surface.AddAndAssignId(&ss);
}
}
hsl.Add(&revs);
}
for(i = 0; i < sbl->l.n; i++) {
Revolved revs = hsl.elem[i],
revsp = hsl.elem[WRAP(i-1, sbl->l.n)];
sb = &(sbl->l.elem[i]);
prev = &(sbl->l.elem[WRAP(i-1, sbl->l.n)]);
for(j = 0; j < 4; j++) {
SCurve sc;
Quaternion qs = Quaternion::From(axis, (PI/2)*j);
// we want Q*(x - p) + p = Q*x + (p - Q*p)
Vector ts = pt.Minus(qs.Rotate(pt));
// If this input curve generate a surface, then trim that
// surface with the rotated version of the input curve.
if(revs.d[j].v) {
sc = {};
sc.isExact = true;
sc.exact = sb->TransformedBy(ts, qs, 1.0);
(sc.exact).MakePwlInto(&(sc.pts));
sc.surfA = revs.d[j];
sc.surfB = revs.d[WRAP(j-1, 4)];
hSCurve hcb = curve.AddAndAssignId(&sc);
STrimBy stb;
stb = STrimBy::EntireCurve(this, hcb, true);
(surface.FindById(sc.surfA))->trim.Add(&stb);
stb = STrimBy::EntireCurve(this, hcb, false);
(surface.FindById(sc.surfB))->trim.Add(&stb);
}
// And if this input curve and the one after it both generated
// surfaces, then trim both of those by the appropriate
// circle.
if(revs.d[j].v && revsp.d[j].v) {
SSurface *ss = surface.FindById(revs.d[j]);
sc = {};
sc.isExact = true;
sc.exact = SBezier::From(ss->ctrl[0][0],
ss->ctrl[0][1],
ss->ctrl[0][2]);
sc.exact.weight[1] = ss->weight[0][1];
(sc.exact).MakePwlInto(&(sc.pts));
sc.surfA = revs.d[j];
sc.surfB = revsp.d[j];
hSCurve hcc = curve.AddAndAssignId(&sc);
STrimBy stb;
stb = STrimBy::EntireCurve(this, hcc, false);
(surface.FindById(sc.surfA))->trim.Add(&stb);
stb = STrimBy::EntireCurve(this, hcc, true);
(surface.FindById(sc.surfB))->trim.Add(&stb);
}
}
}
hsl.Clear();
}
for(i = i0; i < surface.n; i++) {
SSurface *srf = &(surface.elem[i]);
// Revolution of a line; this is potentially a plane, which we can
// rewrite to have degree (1, 1).
if(srf->degm == 1 && srf->degn == 2) {
// close start, far start, far finish
Vector cs, fs, ff;
double d0, d1;
d0 = (srf->ctrl[0][0]).DistanceToLine(pt, axis);
d1 = (srf->ctrl[1][0]).DistanceToLine(pt, axis);
if(d0 > d1) {
cs = srf->ctrl[1][0];
fs = srf->ctrl[0][0];
ff = srf->ctrl[0][2];
} else {
cs = srf->ctrl[0][0];
fs = srf->ctrl[1][0];
ff = srf->ctrl[1][2];
}
// origin close, origin far
Vector oc = cs.ClosestPointOnLine(pt, axis),
of = fs.ClosestPointOnLine(pt, axis);
if(oc.Equals(of)) {
// This is a plane, not a (non-degenerate) cone.
Vector oldn = srf->NormalAt(0.5, 0.5);
Vector u = fs.Minus(of), v;
v = (axis.Cross(u)).WithMagnitude(1);
double vm = (ff.Minus(of)).Dot(v);
v = v.ScaledBy(vm);
srf->degm = 1;
srf->degn = 1;
srf->ctrl[0][0] = of;
srf->ctrl[0][1] = of.Plus(u);
srf->ctrl[1][0] = of.Plus(v);
srf->ctrl[1][1] = of.Plus(u).Plus(v);
srf->weight[0][0] = 1;
srf->weight[0][1] = 1;
srf->weight[1][0] = 1;
srf->weight[1][1] = 1;
if(oldn.Dot(srf->NormalAt(0.5, 0.5)) < 0) {
swap(srf->ctrl[0][0], srf->ctrl[1][0]);
swap(srf->ctrl[0][1], srf->ctrl[1][1]);
}
continue;
}
if(fabs(d0 - d1) < LENGTH_EPS) {
// This is a cylinder; so transpose it so that we'll recognize
// it as a surface of extrusion.
SSurface sn = *srf;
// Transposing u and v flips the normal, so reverse u to
// flip it again and put it back where we started.
sn.degm = 2;
sn.degn = 1;
int dm, dn;
for(dm = 0; dm <= 1; dm++) {
for(dn = 0; dn <= 2; dn++) {
sn.ctrl [dn][dm] = srf->ctrl [1-dm][dn];
sn.weight[dn][dm] = srf->weight[1-dm][dn];
}
}
*srf = sn;
continue;
}
}
}
}
//-----------------------------------------------------------------------------
// Trim this surface against the specified shell, in the way that's appropriate
// for the specified Boolean operation type (and which operand we are). We
// also need a pointer to the shell that contains our own surface, since that
// contains our original trim curves.
//-----------------------------------------------------------------------------
SSurface SSurface::MakeCopyTrimAgainst(SShell *parent,
SShell *sha, SShell *shb,
SShell *into,
int type)
{
bool opA = (parent == sha);
SShell *agnst = opA ? shb : sha;
SSurface ret;
// The returned surface is identical, just the trim curves change
ret = *this;
ret.trim = {};
// First, build a list of the existing trim curves; update them to use
// the split curves.
STrimBy *stb;
for(stb = trim.First(); stb; stb = trim.NextAfter(stb)) {
STrimBy stn = *stb;
stn.curve = (parent->curve.FindById(stn.curve))->newH;
ret.trim.Add(&stn);
}
if(type == SShell::AS_DIFFERENCE && !opA) {
// The second operand of a Boolean difference gets turned inside out
ret.Reverse();
}
// Build up our original trim polygon; remember the coordinates could
// be changed if we just flipped the surface normal, and we are using
// the split curves (not the original curves).
SEdgeList orig = {};
ret.MakeEdgesInto(into, &orig, AS_UV);
ret.trim.Clear();
// which means that we can't necessarily use the old BSP...
SBspUv *origBsp = SBspUv::From(&orig, &ret);
// And now intersect the other shell against us
SEdgeList inter = {};
SSurface *ss;
for(ss = agnst->surface.First(); ss; ss = agnst->surface.NextAfter(ss)) {
SCurve *sc;
for(sc = into->curve.First(); sc; sc = into->curve.NextAfter(sc)) {
if(sc->source != SCurve::FROM_INTERSECTION) continue;
if(opA) {
if(sc->surfA.v != h.v || sc->surfB.v != ss->h.v) continue;
} else {
if(sc->surfB.v != h.v || sc->surfA.v != ss->h.v) continue;
}
int i;
for(i = 1; i < sc->pts.n; i++) {
Vector a = sc->pts.elem[i-1].p,
b = sc->pts.elem[i].p;
Point2d auv, buv;
ss->ClosestPointTo(a, &(auv.x), &(auv.y));
ss->ClosestPointTo(b, &(buv.x), &(buv.y));
int c = (ss->bsp) ? ss->bsp->ClassifyEdge(auv, buv, ss) : SBspUv::OUTSIDE;
if(c != SBspUv::OUTSIDE) {
Vector ta = Vector::From(0, 0, 0);
Vector tb = Vector::From(0, 0, 0);
ret.ClosestPointTo(a, &(ta.x), &(ta.y));
ret.ClosestPointTo(b, &(tb.x), &(tb.y));
Vector tn = ret.NormalAt(ta.x, ta.y);
Vector sn = ss->NormalAt(auv.x, auv.y);
// We are subtracting the portion of our surface that
// lies in the shell, so the in-plane edge normal should
// point opposite to the surface normal.
bool bkwds = true;
if((tn.Cross(b.Minus(a))).Dot(sn) < 0) bkwds = !bkwds;
if(type == SShell::AS_DIFFERENCE && !opA) bkwds = !bkwds;
if(bkwds) {
inter.AddEdge(tb, ta, sc->h.v, 1);
} else {
inter.AddEdge(ta, tb, sc->h.v, 0);
}
}
}
}
}
// Record all the points where more than two edges join, which I will call
// the choosing points. If two edges join at a non-choosing point, then
// they must either both be kept or both be discarded (since that would
// otherwise create an open contour).
SPointList choosing = {};
SEdge *se;
for(se = orig.l.First(); se; se = orig.l.NextAfter(se)) {
choosing.IncrementTagFor(se->a);
choosing.IncrementTagFor(se->b);
}
for(se = inter.l.First(); se; se = inter.l.NextAfter(se)) {
choosing.IncrementTagFor(se->a);
choosing.IncrementTagFor(se->b);
}
SPoint *sp;
for(sp = choosing.l.First(); sp; sp = choosing.l.NextAfter(sp)) {
if(sp->tag == 2) {
sp->tag = 1;
} else {
sp->tag = 0;
}
}
choosing.l.RemoveTagged();
// The list of edges to trim our new surface, a combination of edges from
// our original and intersecting edge lists.
SEdgeList final = {};
while(orig.l.n > 0) {
SEdgeList chain = {};
FindChainAvoiding(&orig, &chain, &choosing);
// Arbitrarily choose an edge within the chain to classify; they
// should all be the same, though.
se = &(chain.l.elem[chain.l.n/2]);
Point2d auv = (se->a).ProjectXy(),
buv = (se->b).ProjectXy();
Vector pt, enin, enout, surfn;
ret.EdgeNormalsWithinSurface(auv, buv, &pt, &enin, &enout, &surfn,
se->auxA, into, sha, shb);
int indir_shell, outdir_shell, indir_orig, outdir_orig;
indir_orig = SShell::INSIDE;
outdir_orig = SShell::OUTSIDE;
agnst->ClassifyEdge(&indir_shell, &outdir_shell,
ret.PointAt(auv), ret.PointAt(buv), pt,
enin, enout, surfn);
if(KeepEdge(type, opA, indir_shell, outdir_shell,
indir_orig, outdir_orig))
{
for(se = chain.l.First(); se; se = chain.l.NextAfter(se)) {
final.AddEdge(se->a, se->b, se->auxA, se->auxB);
}
}
chain.Clear();
}
void SSurface::IntersectAgainst(SSurface *b, SShell *agnstA, SShell *agnstB,
SShell *into)
{
Vector amax, amin, bmax, bmin;
GetAxisAlignedBounding(&amax, &amin);
b->GetAxisAlignedBounding(&bmax, &bmin);
if(Vector::BoundingBoxesDisjoint(amax, amin, bmax, bmin)) {
// They cannot possibly intersect, no curves to generate
return;
}
Vector alongt, alongb;
SBezier oft, ofb;
bool isExtdt = this->IsExtrusion(&oft, &alongt),
isExtdb = b->IsExtrusion(&ofb, &alongb);
if(degm == 1 && degn == 1 && b->degm == 1 && b->degn == 1) {
// Line-line intersection; it's a plane or nothing.
Vector na = NormalAt(0, 0).WithMagnitude(1),
nb = b->NormalAt(0, 0).WithMagnitude(1);
double da = na.Dot(PointAt(0, 0)),
db = nb.Dot(b->PointAt(0, 0));
Vector dl = na.Cross(nb);
if(dl.Magnitude() < LENGTH_EPS) return; // parallel planes
dl = dl.WithMagnitude(1);
Vector p = Vector::AtIntersectionOfPlanes(na, da, nb, db);
// Trim it to the region 0 <= {u,v} <= 1 for each plane; not strictly
// necessary, since line will be split and excess edges culled, but
// this improves speed and robustness.
int i;
double tmax = VERY_POSITIVE, tmin = VERY_NEGATIVE;
for(i = 0; i < 2; i++) {
SSurface *s = (i == 0) ? this : b;
Vector tu, tv;
s->TangentsAt(0, 0, &tu, &tv);
double up, vp, ud, vd;
s->ClosestPointTo(p, &up, &vp);
ud = (dl.Dot(tu)) / tu.MagSquared();
vd = (dl.Dot(tv)) / tv.MagSquared();
// so u = up + t*ud
// v = vp + t*vd
if(ud > LENGTH_EPS) {
tmin = max(tmin, -up/ud);
tmax = min(tmax, (1 - up)/ud);
} else if(ud < -LENGTH_EPS) {
tmax = min(tmax, -up/ud);
tmin = max(tmin, (1 - up)/ud);
} else {
if(up < -LENGTH_EPS || up > 1 + LENGTH_EPS) {
// u is constant, and outside [0, 1]
tmax = VERY_NEGATIVE;
}
}
if(vd > LENGTH_EPS) {
tmin = max(tmin, -vp/vd);
tmax = min(tmax, (1 - vp)/vd);
} else if(vd < -LENGTH_EPS) {
tmax = min(tmax, -vp/vd);
tmin = max(tmin, (1 - vp)/vd);
} else {
if(vp < -LENGTH_EPS || vp > 1 + LENGTH_EPS) {
// v is constant, and outside [0, 1]
tmax = VERY_NEGATIVE;
}
}
}
if(tmax > tmin + LENGTH_EPS) {
SBezier bezier = SBezier::From(p.Plus(dl.ScaledBy(tmin)),
p.Plus(dl.ScaledBy(tmax)));
AddExactIntersectionCurve(&bezier, b, agnstA, agnstB, into);
}
} else if((degm == 1 && degn == 1 && isExtdb) ||
(b->degm == 1 && b->degn == 1 && isExtdt))
{
// The intersection between a plane and a surface of extrusion
SSurface *splane, *sext;
if(degm == 1 && degn == 1) {
splane = this;
sext = b;
} else {
splane = b;
sext = this;
}
Vector n = splane->NormalAt(0, 0).WithMagnitude(1), along;
double d = n.Dot(splane->PointAt(0, 0));
SBezier bezier;
(void)sext->IsExtrusion(&bezier, &along);
if(fabs(n.Dot(along)) < LENGTH_EPS) {
// Direction of extrusion is parallel to plane; so intersection
// is zero or more lines. Build a line within the plane, and
// normal to the direction of extrusion, and intersect that line
// against the surface; each intersection point corresponds to
// a line.
Vector pm, alu, p0, dp;
// a point halfway along the extrusion
pm = ((sext->ctrl[0][0]).Plus(sext->ctrl[0][1])).ScaledBy(0.5);
alu = along.WithMagnitude(1);
dp = (n.Cross(along)).WithMagnitude(1);
// n, alu, and dp form an orthogonal csys; set n component to
// place it on the plane, alu component to lie halfway along
// extrusion, and dp component doesn't matter so zero
p0 = n.ScaledBy(d).Plus(alu.ScaledBy(pm.Dot(alu)));
List<SInter> inters = {};
sext->AllPointsIntersecting(p0, p0.Plus(dp), &inters,
/*asSegment=*/false, /*trimmed=*/false, /*inclTangent=*/true);
SInter *si;
for(si = inters.First(); si; si = inters.NextAfter(si)) {
Vector al = along.ScaledBy(0.5);
SBezier bezier;
bezier = SBezier::From((si->p).Minus(al), (si->p).Plus(al));
AddExactIntersectionCurve(&bezier, b, agnstA, agnstB, into);
}
inters.Clear();
} else {
// Direction of extrusion is not parallel to plane; so
// intersection is projection of extruded curve into our plane.
int i;
for(i = 0; i <= bezier.deg; i++) {
Vector p0 = bezier.ctrl[i],
p1 = p0.Plus(along);
bezier.ctrl[i] =
Vector::AtIntersectionOfPlaneAndLine(n, d, p0, p1, NULL);
}
AddExactIntersectionCurve(&bezier, b, agnstA, agnstB, into);
}
} else if(isExtdt && isExtdb &&
sqrt(fabs(alongt.Dot(alongb))) >
sqrt(alongt.Magnitude() * alongb.Magnitude()) - LENGTH_EPS)
{
// Two surfaces of extrusion along the same axis. So they might
// intersect along some number of lines parallel to the axis.
Vector axis = alongt.WithMagnitude(1);
List<SInter> inters = {};
List<Vector> lv = {};
double a_axis0 = ( ctrl[0][0]).Dot(axis),
a_axis1 = ( ctrl[0][1]).Dot(axis),
b_axis0 = (b->ctrl[0][0]).Dot(axis),
b_axis1 = (b->ctrl[0][1]).Dot(axis);
if(a_axis0 > a_axis1) swap(a_axis0, a_axis1);
if(b_axis0 > b_axis1) swap(b_axis0, b_axis1);
double ab_axis0 = max(a_axis0, b_axis0),
ab_axis1 = min(a_axis1, b_axis1);
if(fabs(ab_axis0 - ab_axis1) < LENGTH_EPS) {
// The line would be zero-length
return;
}
Vector axis0 = axis.ScaledBy(ab_axis0),
axis1 = axis.ScaledBy(ab_axis1),
axisc = (axis0.Plus(axis1)).ScaledBy(0.5);
oft.MakePwlInto(&lv);
int i;
for(i = 0; i < lv.n - 1; i++) {
Vector pa = lv.elem[i], pb = lv.elem[i+1];
pa = pa.Minus(axis.ScaledBy(pa.Dot(axis)));
pb = pb.Minus(axis.ScaledBy(pb.Dot(axis)));
pa = pa.Plus(axisc);
pb = pb.Plus(axisc);
b->AllPointsIntersecting(pa, pb, &inters,
/*asSegment=*/true,/*trimmed=*/false, /*inclTangent=*/false);
}
SInter *si;
for(si = inters.First(); si; si = inters.NextAfter(si)) {
Vector p = (si->p).Minus(axis.ScaledBy((si->p).Dot(axis)));
double ub, vb;
b->ClosestPointTo(p, &ub, &vb, /*mustConverge=*/true);
SSurface plane;
plane = SSurface::FromPlane(p, axis.Normal(0), axis.Normal(1));
b->PointOnSurfaces(this, &plane, &ub, &vb);
p = b->PointAt(ub, vb);
SBezier bezier;
bezier = SBezier::From(p.Plus(axis0), p.Plus(axis1));
AddExactIntersectionCurve(&bezier, b, agnstA, agnstB, into);
}
inters.Clear();
lv.Clear();
} else {
// Try intersecting the surfaces numerically, by a marching algorithm.
// First, we find all the intersections between a surface and the
// boundary of the other surface.
SPointList spl = {};
int a;
for(a = 0; a < 2; a++) {
SShell *shA = (a == 0) ? agnstA : agnstB;
SSurface *srfA = (a == 0) ? this : b,
*srfB = (a == 0) ? b : this;
SEdgeList el = {};
srfA->MakeEdgesInto(shA, &el, MakeAs::XYZ, NULL);
SEdge *se;
for(se = el.l.First(); se; se = el.l.NextAfter(se)) {
List<SInter> lsi = {};
srfB->AllPointsIntersecting(se->a, se->b, &lsi,
/*asSegment=*/true, /*trimmed=*/true, /*inclTangent=*/false);
if(lsi.n == 0) continue;
// Find the other surface that this curve trims.
hSCurve hsc = { (uint32_t)se->auxA };
SCurve *sc = shA->curve.FindById(hsc);
hSSurface hother = (sc->surfA.v == srfA->h.v) ?
sc->surfB : sc->surfA;
SSurface *other = shA->surface.FindById(hother);
SInter *si;
for(si = lsi.First(); si; si = lsi.NextAfter(si)) {
Vector p = si->p;
double u, v;
srfB->ClosestPointTo(p, &u, &v);
srfB->PointOnSurfaces(srfA, other, &u, &v);
p = srfB->PointAt(u, v);
if(!spl.ContainsPoint(p)) {
SPoint sp;
sp.p = p;
// We also need the edge normal, so that we know in
// which direction to march.
srfA->ClosestPointTo(p, &u, &v);
Vector n = srfA->NormalAt(u, v);
sp.auxv = n.Cross((se->b).Minus(se->a));
sp.auxv = (sp.auxv).WithMagnitude(1);
spl.l.Add(&sp);
}
}
lsi.Clear();
}
el.Clear();
}
while(spl.l.n >= 2) {
SCurve sc = {};
sc.surfA = h;
sc.surfB = b->h;
sc.isExact = false;
sc.source = SCurve::Source::INTERSECTION;
Vector start = spl.l.elem[0].p,
startv = spl.l.elem[0].auxv;
spl.l.ClearTags();
spl.l.elem[0].tag = 1;
spl.l.RemoveTagged();
// Our chord tolerance is whatever the user specified
double maxtol = SS.ChordTolMm();
int maxsteps = max(300, SS.GetMaxSegments()*3);
// The curve starts at our starting point.
SCurvePt padd = {};
padd.vertex = true;
padd.p = start;
sc.pts.Add(&padd);
Point2d pa, pb;
Vector np, npc = Vector::From(0, 0, 0);
bool fwd = false;
// Better to start with a too-small step, so that we don't miss
// features of the curve entirely.
double tol, step = maxtol;
for(a = 0; a < maxsteps; a++) {
ClosestPointTo(start, &pa);
b->ClosestPointTo(start, &pb);
Vector na = NormalAt(pa).WithMagnitude(1),
nb = b->NormalAt(pb).WithMagnitude(1);
if(a == 0) {
Vector dp = nb.Cross(na);
if(dp.Dot(startv) < 0) {
// We want to march in the more inward direction.
fwd = true;
} else {
fwd = false;
}
}
int i;
for(i = 0; i < 20; i++) {
Vector dp = nb.Cross(na);
if(!fwd) dp = dp.ScaledBy(-1);
dp = dp.WithMagnitude(step);
np = start.Plus(dp);
npc = ClosestPointOnThisAndSurface(b, np);
tol = (npc.Minus(np)).Magnitude();
if(tol > maxtol*0.8) {
step *= 0.90;
} else {
step /= 0.90;
}
if((tol < maxtol) && (tol > maxtol/2)) {
// If we meet the chord tolerance test, and we're
// not too fine, then we break out.
break;
}
}
SPoint *sp;
for(sp = spl.l.First(); sp; sp = spl.l.NextAfter(sp)) {
if((sp->p).OnLineSegment(start, npc, 2*SS.ChordTolMm())) {
sp->tag = 1;
a = maxsteps;
npc = sp->p;
}
}
padd.p = npc;
padd.vertex = (a == maxsteps);
sc.pts.Add(&padd);
start = npc;
}
spl.l.RemoveTagged();
// And now we split and insert the curve
SCurve split = sc.MakeCopySplitAgainst(agnstA, agnstB, this, b);
sc.Clear();
into->curve.AddAndAssignId(&split);
}
spl.Clear();
}
}
void Group::GenerateShellAndMesh(void) {
bool prevBooleanFailed = booleanFailed;
booleanFailed = false;
Group *srcg = this;
thisShell.Clear();
thisMesh.Clear();
runningShell.Clear();
runningMesh.Clear();
// Don't attempt a lathe or extrusion unless the source section is good:
// planar and not self-intersecting.
bool haveSrc = true;
if(type == EXTRUDE || type == LATHE) {
Group *src = SK.GetGroup(opA);
if(src->polyError.how != POLY_GOOD) {
haveSrc = false;
}
}
if(type == TRANSLATE || type == ROTATE) {
// A step and repeat gets merged against the group's prevous group,
// not our own previous group.
srcg = SK.GetGroup(opA);
GenerateForStepAndRepeat<SShell>(&(srcg->thisShell), &thisShell);
GenerateForStepAndRepeat<SMesh> (&(srcg->thisMesh), &thisMesh);
} else if(type == EXTRUDE && haveSrc) {
Group *src = SK.GetGroup(opA);
Vector translate = Vector::From(h.param(0), h.param(1), h.param(2));
Vector tbot, ttop;
if(subtype == ONE_SIDED) {
tbot = Vector::From(0, 0, 0); ttop = translate.ScaledBy(2);
} else {
tbot = translate.ScaledBy(-1); ttop = translate.ScaledBy(1);
}
SBezierLoopSetSet *sblss = &(src->bezierLoops);
SBezierLoopSet *sbls;
for(sbls = sblss->l.First(); sbls; sbls = sblss->l.NextAfter(sbls)) {
int is = thisShell.surface.n;
// Extrude this outer contour (plus its inner contours, if present)
thisShell.MakeFromExtrusionOf(sbls, tbot, ttop, color);
// And for any plane faces, annotate the model with the entity for
// that face, so that the user can select them with the mouse.
Vector onOrig = sbls->point;
int i;
for(i = is; i < thisShell.surface.n; i++) {
SSurface *ss = &(thisShell.surface.elem[i]);
hEntity face = Entity::NO_ENTITY;
Vector p = ss->PointAt(0, 0),
n = ss->NormalAt(0, 0).WithMagnitude(1);
double d = n.Dot(p);
if(i == is || i == (is + 1)) {
// These are the top and bottom of the shell.
if(fabs((onOrig.Plus(ttop)).Dot(n) - d) < LENGTH_EPS) {
face = Remap(Entity::NO_ENTITY, REMAP_TOP);
ss->face = face.v;
}
if(fabs((onOrig.Plus(tbot)).Dot(n) - d) < LENGTH_EPS) {
face = Remap(Entity::NO_ENTITY, REMAP_BOTTOM);
ss->face = face.v;
}
continue;
}
// So these are the sides
if(ss->degm != 1 || ss->degn != 1) continue;
Entity *e;
for(e = SK.entity.First(); e; e = SK.entity.NextAfter(e)) {
if(e->group.v != opA.v) continue;
if(e->type != Entity::LINE_SEGMENT) continue;
Vector a = SK.GetEntity(e->point[0])->PointGetNum(),
b = SK.GetEntity(e->point[1])->PointGetNum();
a = a.Plus(ttop);
b = b.Plus(ttop);
// Could get taken backwards, so check all cases.
if((a.Equals(ss->ctrl[0][0]) && b.Equals(ss->ctrl[1][0])) ||
(b.Equals(ss->ctrl[0][0]) && a.Equals(ss->ctrl[1][0])) ||
(a.Equals(ss->ctrl[0][1]) && b.Equals(ss->ctrl[1][1])) ||
(b.Equals(ss->ctrl[0][1]) && a.Equals(ss->ctrl[1][1])))
{
face = Remap(e->h, REMAP_LINE_TO_FACE);
ss->face = face.v;
break;
}
}
}
}
} else if(type == LATHE && haveSrc) {
Group *src = SK.GetGroup(opA);
Vector pt = SK.GetEntity(predef.origin)->PointGetNum(),
axis = SK.GetEntity(predef.entityB)->VectorGetNum();
axis = axis.WithMagnitude(1);
SBezierLoopSetSet *sblss = &(src->bezierLoops);
SBezierLoopSet *sbls;
for(sbls = sblss->l.First(); sbls; sbls = sblss->l.NextAfter(sbls)) {
thisShell.MakeFromRevolutionOf(sbls, pt, axis, color, this);
}
} else if(type == LINKED) {
// The imported shell or mesh are copied over, with the appropriate
// transformation applied. We also must remap the face entities.
Vector offset = {
SK.GetParam(h.param(0))->val,
SK.GetParam(h.param(1))->val,
SK.GetParam(h.param(2))->val };
Quaternion q = {
SK.GetParam(h.param(3))->val,
SK.GetParam(h.param(4))->val,
SK.GetParam(h.param(5))->val,
SK.GetParam(h.param(6))->val };
thisMesh.MakeFromTransformationOf(&impMesh, offset, q, scale);
thisMesh.RemapFaces(this, 0);
thisShell.MakeFromTransformationOf(&impShell, offset, q, scale);
thisShell.RemapFaces(this, 0);
}
if(srcg->meshCombine != COMBINE_AS_ASSEMBLE) {
thisShell.MergeCoincidentSurfaces();
}
// So now we've got the mesh or shell for this group. Combine it with
// the previous group's mesh or shell with the requested Boolean, and
// we're done.
Group *prevg = srcg->RunningMeshGroup();
if(prevg->runningMesh.IsEmpty() && thisMesh.IsEmpty() && !forceToMesh) {
SShell *prevs = &(prevg->runningShell);
GenerateForBoolean<SShell>(prevs, &thisShell, &runningShell,
srcg->meshCombine);
if(srcg->meshCombine != COMBINE_AS_ASSEMBLE) {
runningShell.MergeCoincidentSurfaces();
}
// If the Boolean failed, then we should note that in the text screen
// for this group.
booleanFailed = runningShell.booleanFailed;
if(booleanFailed != prevBooleanFailed) {
SS.ScheduleShowTW();
}
} else {
SMesh prevm, thism;
prevm = {};
thism = {};
prevm.MakeFromCopyOf(&(prevg->runningMesh));
prevg->runningShell.TriangulateInto(&prevm);
thism.MakeFromCopyOf(&thisMesh);
thisShell.TriangulateInto(&thism);
SMesh outm = {};
GenerateForBoolean<SMesh>(&prevm, &thism, &outm, srcg->meshCombine);
// And make sure that the output mesh is vertex-to-vertex.
SKdNode *root = SKdNode::From(&outm);
root->SnapToMesh(&outm);
root->MakeMeshInto(&runningMesh);
outm.Clear();
thism.Clear();
prevm.Clear();
}
displayDirty = true;
}
//-----------------------------------------------------------------------------
// Does the given point lie on our shell? There are many cases; inside and
// outside are obvious, but then there's all the edge-on-edge and edge-on-face
// possibilities.
//
// To calculate, we intersect a ray through p with our shell, and classify
// using the closest intersection point. If the ray hits a surface on edge,
// then just reattempt in a different random direction.
//-----------------------------------------------------------------------------
bool SShell::ClassifyEdge(int *indir, int *outdir,
Vector ea, Vector eb,
Vector p,
Vector edge_n_in, Vector edge_n_out, Vector surf_n)
{
List<SInter> l;
ZERO(&l);
srand(0);
// First, check for edge-on-edge
int edge_inters = 0;
Vector inter_surf_n[2], inter_edge_n[2];
SSurface *srf;
for(srf = surface.First(); srf; srf = surface.NextAfter(srf)) {
if(srf->LineEntirelyOutsideBbox(ea, eb, true)) continue;
SEdgeList *sel = &(srf->edges);
SEdge *se;
for(se = sel->l.First(); se; se = sel->l.NextAfter(se)) {
if((ea.Equals(se->a) && eb.Equals(se->b)) ||
(eb.Equals(se->a) && ea.Equals(se->b)) ||
p.OnLineSegment(se->a, se->b))
{
if(edge_inters < 2) {
// Edge-on-edge case
Point2d pm;
srf->ClosestPointTo(p, &pm, false);
// A vector normal to the surface, at the intersection point
inter_surf_n[edge_inters] = srf->NormalAt(pm);
// A vector normal to the intersecting edge (but within the
// intersecting surface) at the intersection point, pointing
// out.
inter_edge_n[edge_inters] =
(inter_surf_n[edge_inters]).Cross((se->b).Minus((se->a)));
}
edge_inters++;
}
}
}
if(edge_inters == 2) {
// TODO, make this use the appropriate curved normals
double dotp[2];
for(int i = 0; i < 2; i++) {
dotp[i] = edge_n_out.DirectionCosineWith(inter_surf_n[i]);
}
if(fabs(dotp[1]) < DOTP_TOL) {
SWAP(double, dotp[0], dotp[1]);
SWAP(Vector, inter_surf_n[0], inter_surf_n[1]);
SWAP(Vector, inter_edge_n[0], inter_edge_n[1]);
}
int coinc = (surf_n.Dot(inter_surf_n[0])) > 0 ? COINC_SAME : COINC_OPP;
if(fabs(dotp[0]) < DOTP_TOL && fabs(dotp[1]) < DOTP_TOL) {
// This is actually an edge on face case, just that the face
// is split into two pieces joining at our edge.
*indir = coinc;
*outdir = coinc;
} else if(fabs(dotp[0]) < DOTP_TOL && dotp[1] > DOTP_TOL) {
if(edge_n_out.Dot(inter_edge_n[0]) > 0) {
*indir = coinc;
*outdir = OUTSIDE;
} else {
*indir = INSIDE;
*outdir = coinc;
}
} else if(fabs(dotp[0]) < DOTP_TOL && dotp[1] < -DOTP_TOL) {
if(edge_n_out.Dot(inter_edge_n[0]) > 0) {
*indir = coinc;
*outdir = INSIDE;
} else {
*indir = OUTSIDE;
*outdir = coinc;
}
} else if(dotp[0] > DOTP_TOL && dotp[1] > DOTP_TOL) {
*indir = INSIDE;
*outdir = OUTSIDE;
} else if(dotp[0] < -DOTP_TOL && dotp[1] < -DOTP_TOL) {
*indir = OUTSIDE;
*outdir = INSIDE;
} else {
// Edge is tangent to the shell at shell's edge, so can't be
// a boundary of the surface.
return false;
}
return true;
}
if(edge_inters != 0) dbp("bad, edge_inters=%d", edge_inters);
// Next, check for edge-on-surface. The ray-casting for edge-inside-shell
// would catch this too, but test separately, for speed (since many edges
// are on surface) and for numerical stability, so we don't pick up
// the additional error from the line intersection.
for(srf = surface.First(); srf; srf = surface.NextAfter(srf)) {
if(srf->LineEntirelyOutsideBbox(ea, eb, true)) continue;
Point2d puv;
srf->ClosestPointTo(p, &(puv.x), &(puv.y), false);
Vector pp = srf->PointAt(puv);
if((pp.Minus(p)).Magnitude() > LENGTH_EPS) continue;
Point2d dummy = { 0, 0 };
int c = srf->bsp->ClassifyPoint(puv, dummy, srf);
if(c == SBspUv::OUTSIDE) continue;
// Edge-on-face (unless edge-on-edge above superceded)
Point2d pin, pout;
srf->ClosestPointTo(p.Plus(edge_n_in), &pin, false);
srf->ClosestPointTo(p.Plus(edge_n_out), &pout, false);
Vector surf_n_in = srf->NormalAt(pin),
surf_n_out = srf->NormalAt(pout);
*indir = ClassifyRegion(edge_n_in, surf_n_in, surf_n);
*outdir = ClassifyRegion(edge_n_out, surf_n_out, surf_n);
return true;
}
// Edge is not on face or on edge; so it's either inside or outside
// the shell, and we'll determine which by raycasting.
int cnt = 0;
for(;;) {
// Cast a ray in a random direction (two-sided so that we test if
// the point lies on a surface, but use only one side for in/out
// testing)
Vector ray = Vector::From(Random(1), Random(1), Random(1));
AllPointsIntersecting(
p.Minus(ray), p.Plus(ray), &l, false, true, false);
// no intersections means it's outside
*indir = OUTSIDE;
*outdir = OUTSIDE;
double dmin = VERY_POSITIVE;
bool onEdge = false;
edge_inters = 0;
SInter *si;
for(si = l.First(); si; si = l.NextAfter(si)) {
double t = ((si->p).Minus(p)).DivPivoting(ray);
if(t*ray.Magnitude() < -LENGTH_EPS) {
// wrong side, doesn't count
continue;
}
double d = ((si->p).Minus(p)).Magnitude();
// We actually should never hit this case; it should have been
// handled above.
if(d < LENGTH_EPS && si->onEdge) {
edge_inters++;
}
if(d < dmin) {
dmin = d;
// Edge does not lie on surface; either strictly inside
// or strictly outside
if((si->surfNormal).Dot(ray) > 0) {
*indir = INSIDE;
*outdir = INSIDE;
} else {
*indir = OUTSIDE;
*outdir = OUTSIDE;
}
onEdge = si->onEdge;
}
}
l.Clear();
// If the point being tested lies exactly on an edge of the shell,
// then our ray always lies on edge, and that's okay. Otherwise
// try again in a different random direction.
if(!onEdge) break;
if(cnt++ > 5) {
dbp("can't find a ray that doesn't hit on edge!");
dbp("on edge = %d, edge_inters = %d", onEdge, edge_inters);
SS.nakedEdges.AddEdge(ea, eb);
break;
}
}
return true;
}