//-----------------------------------------------------------------------------
// 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 SolveSpace::ExportLinesAndMesh(SEdgeList *sel, SBezierList *sbl, SMesh *sm,
Vector u, Vector v, Vector n,
Vector origin, double cameraTan,
VectorFileWriter *out)
{
double s = 1.0 / SS.exportScale;
// Project into the export plane; so when we're done, z doesn't matter,
// and x and y are what goes in the DXF.
SEdge *e;
for(e = sel->l.First(); e; e = sel->l.NextAfter(e)) {
// project into the specified csys, and apply export scale
(e->a) = e->a.InPerspective(u, v, n, origin, cameraTan).ScaledBy(s);
(e->b) = e->b.InPerspective(u, v, n, origin, cameraTan).ScaledBy(s);
}
SBezier *b;
if(sbl) {
for(b = sbl->l.First(); b; b = sbl->l.NextAfter(b)) {
*b = b->InPerspective(u, v, n, origin, cameraTan);
int i;
for(i = 0; i <= b->deg; i++) {
b->ctrl[i] = (b->ctrl[i]).ScaledBy(s);
}
}
}
// If cutter radius compensation is requested, then perform it now
if(fabs(SS.exportOffset) > LENGTH_EPS) {
// assemble those edges into a polygon, and clear the edge list
SPolygon sp;
ZERO(&sp);
sel->AssemblePolygon(&sp, NULL);
sel->Clear();
SPolygon compd;
ZERO(&compd);
sp.normal = Vector::From(0, 0, -1);
sp.FixContourDirections();
sp.OffsetInto(&compd, SS.exportOffset*s);
sp.Clear();
compd.MakeEdgesInto(sel);
compd.Clear();
}
// Now the triangle mesh; project, then build a BSP to perform
// occlusion testing and generated the shaded surfaces.
SMesh smp;
ZERO(&smp);
if(sm) {
Vector l0 = (SS.lightDir[0]).WithMagnitude(1),
l1 = (SS.lightDir[1]).WithMagnitude(1);
STriangle *tr;
for(tr = sm->l.First(); tr; tr = sm->l.NextAfter(tr)) {
STriangle tt = *tr;
tt.a = (tt.a).InPerspective(u, v, n, origin, cameraTan).ScaledBy(s);
tt.b = (tt.b).InPerspective(u, v, n, origin, cameraTan).ScaledBy(s);
tt.c = (tt.c).InPerspective(u, v, n, origin, cameraTan).ScaledBy(s);
// And calculate lighting for the triangle
Vector n = tt.Normal().WithMagnitude(1);
double lighting = SS.ambientIntensity +
max(0, (SS.lightIntensity[0])*(n.Dot(l0))) +
max(0, (SS.lightIntensity[1])*(n.Dot(l1)));
double r = min(1, REDf (tt.meta.color)*lighting),
g = min(1, GREENf(tt.meta.color)*lighting),
b = min(1, BLUEf (tt.meta.color)*lighting);
tt.meta.color = RGBf(r, g, b);
smp.AddTriangle(&tt);
}
}
// Use the BSP routines to generate the split triangles in paint order.
SBsp3 *bsp = SBsp3::FromMesh(&smp);
SMesh sms;
ZERO(&sms);
bsp->GenerateInPaintOrder(&sms);
// And cull the back-facing triangles
STriangle *tr;
sms.l.ClearTags();
for(tr = sms.l.First(); tr; tr = sms.l.NextAfter(tr)) {
Vector n = tr->Normal();
if(n.z < 0) {
tr->tag = 1;
}
}
sms.l.RemoveTagged();
// And now we perform hidden line removal if requested
SEdgeList hlrd;
ZERO(&hlrd);
if(sm && !SS.GW.showHdnLines) {
SKdNode *root = SKdNode::From(&smp);
// Generate the edges where a curved surface turns from front-facing
// to back-facing.
if(SS.GW.showEdges) {
root->MakeCertainEdgesInto(sel, SKdNode::TURNING_EDGES,
false, NULL, NULL);
}
root->ClearTags();
int cnt = 1234;
SEdge *se;
for(se = sel->l.First(); se; se = sel->l.NextAfter(se)) {
if(se->auxA == Style::CONSTRAINT) {
// Constraints should not get hidden line removed; they're
// always on top.
hlrd.AddEdge(se->a, se->b, se->auxA);
continue;
}
SEdgeList out;
ZERO(&out);
// Split the original edge against the mesh
out.AddEdge(se->a, se->b, se->auxA);
root->OcclusionTestLine(*se, &out, cnt);
// the occlusion test splits unnecessarily; so fix those
out.MergeCollinearSegments(se->a, se->b);
cnt++;
// And add the results to our output
SEdge *sen;
for(sen = out.l.First(); sen; sen = out.l.NextAfter(sen)) {
hlrd.AddEdge(sen->a, sen->b, sen->auxA);
}
out.Clear();
}
sel = &hlrd;
}
// We kept the line segments and Beziers separate until now; but put them
// all together, and also project everything into the xy plane, since not
// all export targets ignore the z component of the points.
for(e = sel->l.First(); e; e = sel->l.NextAfter(e)) {
SBezier sb = SBezier::From(e->a, e->b);
sb.auxA = e->auxA;
sbl->l.Add(&sb);
}
for(b = sbl->l.First(); b; b = sbl->l.NextAfter(b)) {
for(int i = 0; i <= b->deg; i++) {
b->ctrl[i].z = 0;
}
}
// If possible, then we will assemble these output curves into loops. They
// will then get exported as closed paths.
SBezierLoopSetSet sblss;
ZERO(&sblss);
SBezierList leftovers;
ZERO(&leftovers);
SSurface srf = SSurface::FromPlane(Vector::From(0, 0, 0),
Vector::From(1, 0, 0),
Vector::From(0, 1, 0));
SPolygon spxyz;
ZERO(&spxyz);
bool allClosed;
SEdge notClosedAt;
sbl->l.ClearTags();
sblss.FindOuterFacesFrom(sbl, &spxyz, &srf,
SS.ChordTolMm()*s,
&allClosed, ¬ClosedAt,
NULL, NULL,
&leftovers);
for(b = leftovers.l.First(); b; b = leftovers.l.NextAfter(b)) {
sblss.AddOpenPath(b);
}
// Now write the lines and triangles to the output file
out->Output(&sblss, &sms);
leftovers.Clear();
spxyz.Clear();
sblss.Clear();
smp.Clear();
sms.Clear();
hlrd.Clear();
}
void SPolygon::UvGridTriangulateInto(SMesh *mesh, SSurface *srf) {
SEdgeList orig;
ZERO(&orig);
MakeEdgesInto(&orig);
SEdgeList holes;
ZERO(&holes);
normal = Vector::From(0, 0, 1);
FixContourDirections();
// Build a rectangular grid, with horizontal and vertical lines in the
// uv plane. The spacing of these lines is adaptive, so calculate that.
List<double> li, lj;
ZERO(&li);
ZERO(&lj);
double v = 0;
li.Add(&v);
srf->MakeTriangulationGridInto(&li, 0, 1, true);
lj.Add(&v);
srf->MakeTriangulationGridInto(&lj, 0, 1, false);
// Now iterate over each quad in the grid. If it's outside the polygon,
// or if it intersects the polygon, then we discard it. Otherwise we
// generate two triangles in the mesh, and cut it out of our polygon.
int i, j;
for(i = 0; i < (li.n - 1); i++) {
for(j = 0; j < (lj.n - 1); j++) {
double us = li.elem[i], uf = li.elem[i+1],
vs = lj.elem[j], vf = lj.elem[j+1];
Vector a = Vector::From(us, vs, 0),
b = Vector::From(us, vf, 0),
c = Vector::From(uf, vf, 0),
d = Vector::From(uf, vs, 0);
if(orig.AnyEdgeCrossings(a, b, NULL) ||
orig.AnyEdgeCrossings(b, c, NULL) ||
orig.AnyEdgeCrossings(c, d, NULL) ||
orig.AnyEdgeCrossings(d, a, NULL))
{
continue;
}
// There's no intersections, so it doesn't matter which point
// we decide to test.
if(!this->ContainsPoint(a)) {
continue;
}
// Add the quad to our mesh
STriangle tr;
ZERO(&tr);
tr.a = a;
tr.b = b;
tr.c = c;
mesh->AddTriangle(&tr);
tr.a = a;
tr.b = c;
tr.c = d;
mesh->AddTriangle(&tr);
holes.AddEdge(a, b);
holes.AddEdge(b, c);
holes.AddEdge(c, d);
holes.AddEdge(d, a);
}
}
holes.CullExtraneousEdges();
SPolygon hp;
ZERO(&hp);
holes.AssemblePolygon(&hp, NULL, true);
SContour *sc;
for(sc = hp.l.First(); sc; sc = hp.l.NextAfter(sc)) {
l.Add(sc);
}
orig.Clear();
holes.Clear();
li.Clear();
lj.Clear();
hp.l.Clear();
UvTriangulateInto(mesh, srf);
}
void SolveSpace::ExportViewOrWireframeTo(char *filename, bool wireframe) {
int i;
SEdgeList edges;
ZERO(&edges);
SBezierList beziers;
ZERO(&beziers);
SMesh *sm = NULL;
if(SS.GW.showShaded) {
Group *g = SK.GetGroup(SS.GW.activeGroup);
g->GenerateDisplayItems();
sm = &(g->displayMesh);
}
if(sm && sm->IsEmpty()) {
sm = NULL;
}
for(i = 0; i < SK.entity.n; i++) {
Entity *e = &(SK.entity.elem[i]);
if(!e->IsVisible()) continue;
if(e->construction) continue;
if(SS.exportPwlCurves || (sm && !SS.GW.showHdnLines) ||
fabs(SS.exportOffset) > LENGTH_EPS)
{
// We will be doing hidden line removal, which we can't do on
// exact curves; so we need things broken down to pwls. Same
// problem with cutter radius compensation.
e->GenerateEdges(&edges);
} else {
e->GenerateBezierCurves(&beziers);
}
}
if(SS.GW.showEdges) {
Group *g = SK.GetGroup(SS.GW.activeGroup);
g->GenerateDisplayItems();
SEdgeList *selr = &(g->displayEdges);
SEdge *se;
for(se = selr->l.First(); se; se = selr->l.NextAfter(se)) {
edges.AddEdge(se->a, se->b, Style::SOLID_EDGE);
}
}
if(SS.GW.showConstraints) {
Constraint *c;
for(c = SK.constraint.First(); c; c = SK.constraint.NextAfter(c)) {
c->GetEdges(&edges);
}
}
if(wireframe) {
VectorFileWriter *out = VectorFileWriter::ForFile(filename);
if(out) {
ExportWireframeCurves(&edges, &beziers, out);
}
} else {
Vector u = SS.GW.projRight,
v = SS.GW.projUp,
n = u.Cross(v),
origin = SS.GW.offset.ScaledBy(-1);
VectorFileWriter *out = VectorFileWriter::ForFile(filename);
if(out) {
ExportLinesAndMesh(&edges, &beziers, sm,
u, v, n, origin, SS.CameraTangent()*SS.GW.scale,
out);
}
if(out && !out->HasCanvasSize()) {
// These file formats don't have a canvas size, so they just
// get exported in the raw coordinate system. So indicate what
// that was on-screen.
SS.justExportedInfo.draw = true;
SS.justExportedInfo.pt = origin;
SS.justExportedInfo.u = u;
SS.justExportedInfo.v = v;
InvalidateGraphics();
}
}
edges.Clear();
beziers.Clear();
}
