//-----------------------------------------------------------------------------
// An export helper function. We start with a list of Bezier curves, and
// assemble them into loops. We find the outer loops, and find the outer loops'
// inner loops, and group them accordingly.
//-----------------------------------------------------------------------------
void SBezierLoopSetSet::FindOuterFacesFrom(SBezierList *sbl, SPolygon *spxyz,
SSurface *srfuv,
double chordTol,
bool *allClosed, SEdge *notClosedAt,
bool *allCoplanar, Vector *notCoplanarAt,
SBezierList *openContours)
{
SSurface srfPlane;
if(!srfuv) {
Vector p, u, v;
*allCoplanar =
sbl->GetPlaneContainingBeziers(&p, &u, &v, notCoplanarAt);
if(!*allCoplanar) {
// Don't even try to assemble them into loops if they're not
// all coplanar.
if(openContours) {
SBezier *sb;
for(sb = sbl->l.First(); sb; sb = sbl->l.NextAfter(sb)) {
openContours->l.Add(sb);
}
}
return;
}
// All the curves lie in a plane through p with basis vectors u and v.
srfPlane = SSurface::FromPlane(p, u, v);
srfuv = &srfPlane;
}
int i, j;
// Assemble the Bezier trim curves into closed loops; we also get the
// piecewise linearization of the curves (in the SPolygon spxyz), as a
// calculation aid for the loop direction.
SBezierLoopSet sbls = SBezierLoopSet::From(sbl, spxyz, chordTol,
allClosed, notClosedAt,
openContours);
if(sbls.l.n != spxyz->l.n) return;
// Convert the xyz piecewise linear to uv piecewise linear.
SPolygon spuv;
ZERO(&spuv);
SContour *sc;
for(sc = spxyz->l.First(); sc; sc = spxyz->l.NextAfter(sc)) {
spuv.AddEmptyContour();
SPoint *pt;
for(pt = sc->l.First(); pt; pt = sc->l.NextAfter(pt)) {
double u, v;
srfuv->ClosestPointTo(pt->p, &u, &v);
spuv.l.elem[spuv.l.n - 1].AddPoint(Vector::From(u, v, 0));
}
}
spuv.normal = Vector::From(0, 0, 1); // must be, since it's in xy plane now
static const int OUTER_LOOP = 10;
static const int INNER_LOOP = 20;
static const int USED_LOOP = 30;
// Fix the contour directions; we do this properly, in uv space, so it
// works for curved surfaces too (important for STEP export).
spuv.FixContourDirections();
for(i = 0; i < spuv.l.n; i++) {
SContour *contour = &(spuv.l.elem[i]);
SBezierLoop *bl = &(sbls.l.elem[i]);
if(contour->tag) {
// This contour got reversed in the polygon to make the directions
// consistent, so the same must be necessary for the Bezier loop.
bl->Reverse();
}
if(contour->IsClockwiseProjdToNormal(spuv.normal)) {
bl->tag = INNER_LOOP;
} else {
bl->tag = OUTER_LOOP;
}
}
bool loopsRemaining = true;
while(loopsRemaining) {
loopsRemaining = false;
for(i = 0; i < sbls.l.n; i++) {
SBezierLoop *loop = &(sbls.l.elem[i]);
if(loop->tag != OUTER_LOOP) continue;
// Check if this contour contains any outer loops; if it does, then
// we should do those "inner outer loops" first; otherwise we
// will steal their holes, since their holes also lie inside this
// contour.
for(j = 0; j < sbls.l.n; j++) {
SBezierLoop *outer = &(sbls.l.elem[j]);
if(i == j) continue;
if(outer->tag != OUTER_LOOP) continue;
Vector p = spuv.l.elem[j].AnyEdgeMidpoint();
if(spuv.l.elem[i].ContainsPointProjdToNormal(spuv.normal, p)) {
break;
}
}
if(j < sbls.l.n) {
// It does, can't do this one yet.
continue;
}
SBezierLoopSet outerAndInners;
ZERO(&outerAndInners);
loopsRemaining = true;
loop->tag = USED_LOOP;
outerAndInners.l.Add(loop);
int auxA = 0;
if(loop->l.n > 0) auxA = loop->l.elem[0].auxA;
for(j = 0; j < sbls.l.n; j++) {
SBezierLoop *inner = &(sbls.l.elem[j]);
if(inner->tag != INNER_LOOP) continue;
if(inner->l.n < 1) continue;
if(inner->l.elem[0].auxA != auxA) continue;
Vector p = spuv.l.elem[j].AnyEdgeMidpoint();
if(spuv.l.elem[i].ContainsPointProjdToNormal(spuv.normal, p)) {
outerAndInners.l.Add(inner);
inner->tag = USED_LOOP;
}
}
outerAndInners.point = srfuv->PointAt(0, 0);
outerAndInners.normal = srfuv->NormalAt(0, 0);
l.Add(&outerAndInners);
}
}
// If we have poorly-formed loops--for example, overlapping zero-area
// stuff--then we can end up with leftovers. We use this function to
// group stuff into closed paths for export when possible, so it's bad
// to screw up on that stuff. So just add them onto the open curve list.
// Very ugly, but better than losing curves.
for(i = 0; i < sbls.l.n; i++) {
SBezierLoop *loop = &(sbls.l.elem[i]);
if(loop->tag == USED_LOOP) continue;
if(openContours) {
SBezier *sb;
for(sb = loop->l.First(); sb; sb = loop->l.NextAfter(sb)) {
openContours->l.Add(sb);
}
}
loop->Clear();
// but don't free the used loops, since we shallow-copied them to
// ourself
}
sbls.l.Clear(); // not sbls.Clear(), since that would deep-clear
spuv.Clear();
}
void SolveSpaceUI::MenuAnalyze(int id) {
SS.GW.GroupSelection();
#define gs (SS.GW.gs)
switch(id) {
case GraphicsWindow::MNU_STEP_DIM:
if(gs.constraints == 1 && gs.n == 0) {
Constraint *c = SK.GetConstraint(gs.constraint[0]);
if(c->HasLabel() && !c->reference) {
SS.TW.shown.dimFinish = c->valA;
SS.TW.shown.dimSteps = 10;
SS.TW.shown.dimIsDistance =
(c->type != Constraint::ANGLE) &&
(c->type != Constraint::LENGTH_RATIO) &&
(c->type != Constraint::LENGTH_DIFFERENCE);
SS.TW.shown.constraint = c->h;
SS.TW.shown.screen = TextWindow::SCREEN_STEP_DIMENSION;
// The step params are specified in the text window,
// so force that to be shown.
SS.GW.ForceTextWindowShown();
SS.ScheduleShowTW();
SS.GW.ClearSelection();
} else {
Error("Constraint must have a label, and must not be "
"a reference dimension.");
}
} else {
Error("Bad selection for step dimension; select a constraint.");
}
break;
case GraphicsWindow::MNU_NAKED_EDGES: {
SS.nakedEdges.Clear();
Group *g = SK.GetGroup(SS.GW.activeGroup);
SMesh *m = &(g->displayMesh);
SKdNode *root = SKdNode::From(m);
bool inters, leaks;
root->MakeCertainEdgesInto(&(SS.nakedEdges),
SKdNode::NAKED_OR_SELF_INTER_EDGES, true, &inters, &leaks);
InvalidateGraphics();
const char *intersMsg = inters ?
"The mesh is self-intersecting (NOT okay, invalid)." :
"The mesh is not self-intersecting (okay, valid).";
const char *leaksMsg = leaks ?
"The mesh has naked edges (NOT okay, invalid)." :
"The mesh is watertight (okay, valid).";
std::string cntMsg = ssprintf("\n\nThe model contains %d triangles, from "
"%d surfaces.", g->displayMesh.l.n, g->runningShell.surface.n);
if(SS.nakedEdges.l.n == 0) {
Message("%s\n\n%s\n\nZero problematic edges, good.%s",
intersMsg, leaksMsg, cntMsg.c_str());
} else {
Error("%s\n\n%s\n\n%d problematic edges, bad.%s",
intersMsg, leaksMsg, SS.nakedEdges.l.n, cntMsg.c_str());
}
break;
}
case GraphicsWindow::MNU_INTERFERENCE: {
SS.nakedEdges.Clear();
SMesh *m = &(SK.GetGroup(SS.GW.activeGroup)->displayMesh);
SKdNode *root = SKdNode::From(m);
bool inters, leaks;
root->MakeCertainEdgesInto(&(SS.nakedEdges),
SKdNode::SELF_INTER_EDGES, false, &inters, &leaks);
InvalidateGraphics();
if(inters) {
Error("%d edges interfere with other triangles, bad.",
SS.nakedEdges.l.n);
} else {
Message("The assembly does not interfere, good.");
}
break;
}
case GraphicsWindow::MNU_VOLUME: {
SMesh *m = &(SK.GetGroup(SS.GW.activeGroup)->displayMesh);
double vol = 0;
int i;
for(i = 0; i < m->l.n; i++) {
STriangle tr = m->l.elem[i];
// Translate to place vertex A at (x, y, 0)
Vector trans = Vector::From(tr.a.x, tr.a.y, 0);
tr.a = (tr.a).Minus(trans);
tr.b = (tr.b).Minus(trans);
tr.c = (tr.c).Minus(trans);
// Rotate to place vertex B on the y-axis. Depending on
// whether the triangle is CW or CCW, C is either to the
// right or to the left of the y-axis. This handles the
// sign of our normal.
Vector u = Vector::From(-tr.b.y, tr.b.x, 0);
u = u.WithMagnitude(1);
Vector v = Vector::From(tr.b.x, tr.b.y, 0);
v = v.WithMagnitude(1);
Vector n = Vector::From(0, 0, 1);
tr.a = (tr.a).DotInToCsys(u, v, n);
tr.b = (tr.b).DotInToCsys(u, v, n);
tr.c = (tr.c).DotInToCsys(u, v, n);
n = tr.Normal().WithMagnitude(1);
// Triangles on edge don't contribute
if(fabs(n.z) < LENGTH_EPS) continue;
// The plane has equation p dot n = a dot n
double d = (tr.a).Dot(n);
// nx*x + ny*y + nz*z = d
// nz*z = d - nx*x - ny*y
double A = -n.x/n.z, B = -n.y/n.z, C = d/n.z;
double mac = tr.c.y/tr.c.x, mbc = (tr.c.y - tr.b.y)/tr.c.x;
double xc = tr.c.x, yb = tr.b.y;
// I asked Maple for
// int(int(A*x + B*y +C, y=mac*x..(mbc*x + yb)), x=0..xc);
double integral =
(1.0/3)*(
A*(mbc-mac)+
(1.0/2)*B*(mbc*mbc-mac*mac)
)*(xc*xc*xc)+
(1.0/2)*(A*yb+B*yb*mbc+C*(mbc-mac))*xc*xc+
C*yb*xc+
(1.0/2)*B*yb*yb*xc;
vol += integral;
}
std::string msg = ssprintf("The volume of the solid model is:\n\n"" %.3f %s^3",
vol / pow(SS.MmPerUnit(), 3),
SS.UnitName());
if(SS.viewUnits == SolveSpaceUI::UNIT_MM) {
msg += ssprintf("\n %.2f mL", vol/(10*10*10));
}
msg += "\n\nCurved surfaces have been approximated as triangles.\n"
"This introduces error, typically of around 1%.";
Message("%s", msg.c_str());
break;
}
case GraphicsWindow::MNU_AREA: {
Group *g = SK.GetGroup(SS.GW.activeGroup);
if(g->polyError.how != Group::POLY_GOOD) {
Error("This group does not contain a correctly-formed "
"2d closed area. It is open, not coplanar, or self-"
"intersecting.");
break;
}
SEdgeList sel = {};
g->polyLoops.MakeEdgesInto(&sel);
SPolygon sp = {};
sel.AssemblePolygon(&sp, NULL, true);
sp.normal = sp.ComputeNormal();
sp.FixContourDirections();
double area = sp.SignedArea();
double scale = SS.MmPerUnit();
Message("The area of the region sketched in this group is:\n\n"
" %.3f %s^2\n\n"
"Curves have been approximated as piecewise linear.\n"
"This introduces error, typically of around 1%%.",
area / (scale*scale),
SS.UnitName());
sel.Clear();
sp.Clear();
break;
}
case GraphicsWindow::MNU_SHOW_DOF:
// This works like a normal solve, except that it calculates
// which variables are free/bound at the same time.
SS.GenerateAll(SolveSpaceUI::GENERATE_ALL, true);
break;
case GraphicsWindow::MNU_TRACE_PT:
if(gs.points == 1 && gs.n == 1) {
SS.traced.point = gs.point[0];
SS.GW.ClearSelection();
} else {
Error("Bad selection for trace; select a single point.");
}
break;
case GraphicsWindow::MNU_STOP_TRACING: {
std::string exportFile;
if(GetSaveFile(&exportFile, "", CsvFileFilter)) {
FILE *f = ssfopen(exportFile, "wb");
if(f) {
int i;
SContour *sc = &(SS.traced.path);
for(i = 0; i < sc->l.n; i++) {
Vector p = sc->l.elem[i].p;
double s = SS.exportScale;
fprintf(f, "%.10f, %.10f, %.10f\r\n",
p.x/s, p.y/s, p.z/s);
}
fclose(f);
} else {
Error("Couldn't write to '%s'", exportFile.c_str());
}
}
// Clear the trace, and stop tracing
SS.traced.point = Entity::NO_ENTITY;
SS.traced.path.l.Clear();
InvalidateGraphics();
break;
}
default: oops();
}
}
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();
}