C++ Group::GenerateDisplayItems方法代码示例

void Group::GenerateDisplayItems(void) {
    // This is potentially slow (since we've got to triangulate a shell, or
    // to find the emphasized edges for a mesh), so we will run it only
    // if its inputs have changed.
    if(displayDirty) {
        Group *pg = RunningMeshGroup();
        if(pg && thisMesh.IsEmpty() && thisShell.IsEmpty()) {
            // We don't contribute any new solid model in this group, so our
            // display items are identical to the previous group's; which means
            // that we can just display those, and stop ourselves from
            // recalculating for those every time we get a change in this group.
            //
            // Note that this can end up recursing multiple times (if multiple
            // groups that contribute no solid model exist in sequence), but
            // that's okay.
            pg->GenerateDisplayItems();

            displayMesh.Clear();
            displayMesh.MakeFromCopyOf(&(pg->displayMesh));

            displayEdges.Clear();
            displayOutlines.Clear();
            if(SS.GW.showEdges) {
                SEdge *se;
                SEdgeList *src = &(pg->displayEdges);
                for(se = src->l.First(); se; se = src->l.NextAfter(se)) {
                    displayEdges.l.Add(se);
                }
                displayOutlines.MakeFromCopyOf(&pg->displayOutlines);
            }
        } else {
            // We do contribute new solid model, so we have to triangulate the
            // shell, and edge-find the mesh.
            displayMesh.Clear();
            runningShell.TriangulateInto(&displayMesh);
            STriangle *t;
            for(t = runningMesh.l.First(); t; t = runningMesh.l.NextAfter(t)) {
                STriangle trn = *t;
                Vector n = trn.Normal();
                trn.an = n;
                trn.bn = n;
                trn.cn = n;
                displayMesh.AddTriangle(&trn);
            }

            displayEdges.Clear();
            displayOutlines.Clear();

            if(SS.GW.showEdges) {
                if(runningMesh.l.n > 0) {
                    // Triangle mesh only; no shell or emphasized edges.
                    runningMesh.MakeCertainEdgesAndOutlinesInto(
                        &displayEdges, &displayOutlines, SKdNode::EMPHASIZED_EDGES);
                } else {
                    displayMesh.MakeCertainEdgesAndOutlinesInto(
                        &displayEdges, &displayOutlines, SKdNode::SHARP_EDGES);
                }
            }
        }

        displayDirty = false;
    }
}

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();
}

void GraphicsWindow::LoopOverPoints(const std::vector<Entity *> &entities,
                                    const std::vector<hEntity> &faces,
                                    Point2d *pmax, Point2d *pmin, double *wmin,
                                    bool usePerspective, bool includeMesh) {

    int i, j;
    for(Entity *e : entities) {
        if(e->IsPoint()) {
            HandlePointForZoomToFit(e->PointGetNum(), pmax, pmin, wmin, usePerspective);
        } else if(e->type == Entity::CIRCLE) {
            // Lots of entities can extend outside the bbox of their points,
            // but circles are particularly bad. We want to get things halfway
            // reasonable without the mesh, because a zoom to fit is used to
            // set the zoom level to set the chord tol.
            double r = e->CircleGetRadiusNum();
            Vector c = SK.GetEntity(e->point[0])->PointGetNum();
            Quaternion q = SK.GetEntity(e->normal)->NormalGetNum();
            for(j = 0; j < 4; j++) {
                Vector p = (j == 0) ? (c.Plus(q.RotationU().ScaledBy( r))) :
                           (j == 1) ? (c.Plus(q.RotationU().ScaledBy(-r))) :
                           (j == 2) ? (c.Plus(q.RotationV().ScaledBy( r))) :
                                      (c.Plus(q.RotationV().ScaledBy(-r)));
                HandlePointForZoomToFit(p, pmax, pmin, wmin, usePerspective);
            }
        } else {
            // We have to iterate children points, because we can select entites without points
            for(int i = 0; i < MAX_POINTS_IN_ENTITY; i++) {
                if(e->point[i].v == 0) break;
                Vector p = SK.GetEntity(e->point[i])->PointGetNum();
                HandlePointForZoomToFit(p, pmax, pmin, wmin, usePerspective);
            }
        }
    }

    if(!includeMesh && faces.empty()) return;

    Group *g = SK.GetGroup(activeGroup);
    g->GenerateDisplayItems();
    for(i = 0; i < g->displayMesh.l.n; i++) {
        STriangle *tr = &(g->displayMesh.l.elem[i]);
        if(!includeMesh) {
            bool found = false;
            for(const hEntity &face : faces) {
                if(face.v != tr->meta.face) continue;
                found = true;
                break;
            }
            if(!found) continue;
        }
        HandlePointForZoomToFit(tr->a, pmax, pmin, wmin, usePerspective);
        HandlePointForZoomToFit(tr->b, pmax, pmin, wmin, usePerspective);
        HandlePointForZoomToFit(tr->c, pmax, pmin, wmin, usePerspective);
    }
    if(!includeMesh) return;
    for(i = 0; i < g->polyLoops.l.n; i++) {
        SContour *sc = &(g->polyLoops.l.elem[i]);
        for(j = 0; j < sc->l.n; j++) {
            HandlePointForZoomToFit(sc->l.elem[j].p, pmax, pmin, wmin, usePerspective);
        }
    }
}

void SolveSpace::ExportSectionTo(char *filename) {
    Vector gn = (SS.GW.projRight).Cross(SS.GW.projUp);
    gn = gn.WithMagnitude(1);

    Group *g = SK.GetGroup(SS.GW.activeGroup);
    g->GenerateDisplayItems();
    if(g->displayMesh.IsEmpty()) {
        Error("No solid model present; draw one with extrudes and revolves, "
              "or use Export 2d View to export bare lines and curves.");
        return;
    }
    
    // The plane in which the exported section lies; need this because we'll
    // reorient from that plane into the xy plane before exporting.
    Vector origin, u, v, n;
    double d;

    SS.GW.GroupSelection();
#define gs (SS.GW.gs)
    if((gs.n == 0 && g->activeWorkplane.v != Entity::FREE_IN_3D.v)) {
        Entity *wrkpl = SK.GetEntity(g->activeWorkplane);
        origin = wrkpl->WorkplaneGetOffset();
        n = wrkpl->Normal()->NormalN();
        u = wrkpl->Normal()->NormalU();
        v = wrkpl->Normal()->NormalV();
    } else if(gs.n == 1 && gs.faces == 1) {
        Entity *face = SK.GetEntity(gs.entity[0]);
        origin = face->FaceGetPointNum();
        n = face->FaceGetNormalNum();
        if(n.Dot(gn) < 0) n = n.ScaledBy(-1);
        u = n.Normal(0);
        v = n.Normal(1);
    } else if(gs.n == 3 && gs.vectors == 2 && gs.points == 1) {
        Vector ut = SK.GetEntity(gs.entity[0])->VectorGetNum(),
               vt = SK.GetEntity(gs.entity[1])->VectorGetNum();
        ut = ut.WithMagnitude(1);
        vt = vt.WithMagnitude(1);

        if(fabs(SS.GW.projUp.Dot(vt)) < fabs(SS.GW.projUp.Dot(ut))) {
            SWAP(Vector, ut, vt);
        }
        if(SS.GW.projRight.Dot(ut) < 0) ut = ut.ScaledBy(-1);
        if(SS.GW.projUp.   Dot(vt) < 0) vt = vt.ScaledBy(-1);

        origin = SK.GetEntity(gs.point[0])->PointGetNum();
        n = ut.Cross(vt);
        u = ut.WithMagnitude(1);
        v = (n.Cross(u)).WithMagnitude(1);
    } else {
        Error("Bad selection for export section. Please select:\n\n"
              "    * nothing, with an active workplane "
                        "(workplane is section plane)\n"
              "    * a face (section plane through face)\n"
              "    * a point and two line segments "
                        "(plane through point and parallel to lines)\n");
        return;
    }
    SS.GW.ClearSelection();

    n = n.WithMagnitude(1);
    d = origin.Dot(n);

    SEdgeList el;
    ZERO(&el);
    SBezierList bl;
    ZERO(&bl);

    // If there's a mesh, then grab the edges from it.
    g->runningMesh.MakeEdgesInPlaneInto(&el, n, d);

    // If there's a shell, then grab the edges and possibly Beziers.
    g->runningShell.MakeSectionEdgesInto(n, d,
       &el, 
       (SS.exportPwlCurves || fabs(SS.exportOffset) > LENGTH_EPS) ? NULL : &bl);

    // All of these are solid model edges, so use the appropriate style.
    SEdge *se;
    for(se = el.l.First(); se; se = el.l.NextAfter(se)) {
        se->auxA = Style::SOLID_EDGE;
    }
    SBezier *sb;
    for(sb = bl.l.First(); sb; sb = bl.l.NextAfter(sb)) {
        sb->auxA = Style::SOLID_EDGE;
    }

    el.CullExtraneousEdges();
    bl.CullIdenticalBeziers();

    // And write the edges.
    VectorFileWriter *out = VectorFileWriter::ForFile(filename);
    if(out) {
        // parallel projection (no perspective), and no mesh
        ExportLinesAndMesh(&el, &bl, NULL,
                           u, v, n, origin, 0,
                           out);
    }
    el.Clear();
    bl.Clear();
}