C++ SPCurve::last_segment方法代码示例

void spdc_concat_colors_and_flush(FreehandBase *dc, gboolean forceclosed)
{
    // Concat RBG
    SPCurve *c = dc->green_curve;
    Inkscape::Preferences *prefs = Inkscape::Preferences::get();
    // Green
    dc->green_curve = new SPCurve();
    while (dc->green_bpaths) {
        sp_canvas_item_destroy(SP_CANVAS_ITEM(dc->green_bpaths->data));
        dc->green_bpaths = g_slist_remove(dc->green_bpaths, dc->green_bpaths->data);
    }

    // Blue
    c->append_continuous(dc->blue_curve, 0.0625);
    dc->blue_curve->reset();
    sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->blue_bpath), NULL);

    // Red
    if (dc->red_curve_is_valid) {
        c->append_continuous(dc->red_curve, 0.0625);
    }
    dc->red_curve->reset();
    sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->red_bpath), NULL);

    if (c->is_empty()) {
        c->unref();
        return;
    }

    // Step A - test, whether we ended on green anchor
    if ( forceclosed || ( dc->green_anchor && dc->green_anchor->active ) ) {
        // We hit green anchor, closing Green-Blue-Red
        dc->desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Path is closed."));
        c->closepath_current();
        // Closed path, just flush
        spdc_flush_white(dc, c);
        c->unref();
        return;
    }

    // Step B - both start and end anchored to same curve
    if ( dc->sa && dc->ea
         && ( dc->sa->curve == dc->ea->curve )
         && ( ( dc->sa != dc->ea )
              || dc->sa->curve->is_closed() ) )
    {
        // We hit bot start and end of single curve, closing paths
        dc->desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Closing path."));
        if (dc->sa->start && !(dc->sa->curve->is_closed()) ) {
            c = reverse_then_unref(c);
        }
        if(prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 1 || 
            prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 2){
            dc->overwrite_curve->append_continuous(c, 0.0625);
            c->unref();
            dc->overwrite_curve->closepath_current();
            if(dc->sa){
                dc->white_curves = g_slist_remove(dc->white_curves, dc->sa->curve);
                dc->white_curves = g_slist_append(dc->white_curves, dc->overwrite_curve);
            }
        }else{
            dc->sa->curve->append_continuous(c, 0.0625);
            c->unref();
            dc->sa->curve->closepath_current();
        }
        spdc_flush_white(dc, NULL);
        return;
    }

    // Step C - test start
    if (dc->sa) {
        SPCurve *s = dc->sa->curve;
        dc->white_curves = g_slist_remove(dc->white_curves, s);
        if(prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 1 || 
            prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 2){
                s = dc->overwrite_curve;
        }
        if (dc->sa->start) {
            s = reverse_then_unref(s);
        }
        s->append_continuous(c, 0.0625);
        c->unref();
        c = s;
    } else /* Step D - test end */ if (dc->ea) {
        SPCurve *e = dc->ea->curve;
        dc->white_curves = g_slist_remove(dc->white_curves, e);
        if (!dc->ea->start) {
            e = reverse_then_unref(e);
        }
        if(prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 1 || 
            prefs->getInt(tool_name(dc) + "/freehand-mode", 0) == 2){
                e = reverse_then_unref(e);
                Geom::CubicBezier const * cubic = dynamic_cast<Geom::CubicBezier const*>(&*e->last_segment());
                SPCurve *lastSeg = new SPCurve();
                if(cubic){
                    lastSeg->moveto((*cubic)[0]);
                    lastSeg->curveto((*cubic)[1],(*cubic)[3],(*cubic)[3]);
                    if( e->get_segment_count() == 1){
                        e = lastSeg;
                    }else{
//.........这里部分代码省略.........

void
LPESimplify::generateHelperPathAndSmooth(Geom::PathVector &result)
{
    if(steps < 1) {
        return;
    }
    Geom::PathVector tmp_path;
    Geom::CubicBezier const *cubic = NULL;
    for (Geom::PathVector::iterator path_it = result.begin(); path_it != result.end(); ++path_it) {
        if (path_it->empty()) {
            continue;
        }

        Geom::Path::iterator curve_it1 = path_it->begin(); // incoming curve
        Geom::Path::iterator curve_it2 = ++(path_it->begin());// outgoing curve
        Geom::Path::iterator curve_endit = path_it->end_default(); // this determines when the loop has to stop
        SPCurve *nCurve = new SPCurve();
        if (path_it->closed()) {
            // if the path is closed, maybe we have to stop a bit earlier because the
            // closing line segment has zerolength.
            const Geom::Curve &closingline =
                path_it->back_closed(); // the closing line segment is always of type
            // Geom::LineSegment.
            if (are_near(closingline.initialPoint(), closingline.finalPoint())) {
                // closingline.isDegenerate() did not work, because it only checks for
                // *exact* zero length, which goes wrong for relative coordinates and
                // rounding errors...
                // the closing line segment has zero-length. So stop before that one!
                curve_endit = path_it->end_open();
            }
        }
        if(helper_size > 0) {
            drawNode(curve_it1->initialPoint());
        }
        nCurve->moveto(curve_it1->initialPoint());
        Geom::Point start = Geom::Point(0,0);
        while (curve_it1 != curve_endit) {
            cubic = dynamic_cast<Geom::CubicBezier const *>(&*curve_it1);
            Geom::Point point_at1 = curve_it1->initialPoint();
            Geom::Point point_at2 = curve_it1->finalPoint();
            Geom::Point point_at3 = curve_it1->finalPoint();
            Geom::Point point_at4 = curve_it1->finalPoint();

            if(start == Geom::Point(0,0)) {
                start = point_at1;
            }

            if (cubic) {
                point_at1 = (*cubic)[1];
                point_at2 = (*cubic)[2];
            }

            if(path_it->closed() && curve_it2 == curve_endit) {
                point_at4 = start;
            }
            if(curve_it2 != curve_endit) {
                cubic = dynamic_cast<Geom::CubicBezier const *>(&*curve_it2);
                if (cubic) {
                    point_at4 = (*cubic)[1];
                }
            }
            Geom::Ray ray1(point_at2, point_at3);
            Geom::Ray ray2(point_at3, point_at4);
            double angle1 = Geom::deg_from_rad(ray1.angle());
            double angle2 = Geom::deg_from_rad(ray2.angle());
            if((smooth_angles  >= std::abs(angle2 - angle1)) && !are_near(point_at4,point_at3) && !are_near(point_at2,point_at3)) {
                double dist = Geom::distance(point_at2,point_at3);
                Geom::Angle angleFixed = ray2.angle();
                angleFixed -= Geom::Angle::from_degrees(180.0);
                point_at2 =  Geom::Point::polar(angleFixed, dist) + point_at3;
            }
            nCurve->curveto(point_at1, point_at2, curve_it1->finalPoint());
            cubic = dynamic_cast<Geom::CubicBezier const *>(nCurve->last_segment());
            if (cubic) {
                point_at1 = (*cubic)[1];
                point_at2 = (*cubic)[2];
                if(helper_size > 0) {
                    if(!are_near((*cubic)[0],(*cubic)[1])) {
                        drawHandle((*cubic)[1]);
                        drawHandleLine((*cubic)[0],(*cubic)[1]);
                    }
                    if(!are_near((*cubic)[3],(*cubic)[2])) {
                        drawHandle((*cubic)[2]);
                        drawHandleLine((*cubic)[3],(*cubic)[2]);
                    }
                }
            }
            if(helper_size > 0) {
                drawNode(curve_it1->finalPoint());
            }
            ++curve_it1;
            ++curve_it2;
        }
        if (path_it->closed()) {
            nCurve->closepath_current();
        }
        tmp_path.push_back(nCurve->get_pathvector()[0]);
        nCurve->reset();
        delete nCurve;
    }
//.........这里部分代码省略.........