C++ PathVector::empty方法代码示例

// FIXME: why is 'transform' argument not used?
void
PrintLatex::print_pathvector(SVGOStringStream &os, Geom::PathVector const &pathv_in, const Geom::Affine & /*transform*/)
{
    if (pathv_in.empty())
        return;

//    Geom::Affine tf=transform;   // why was this here?
    Geom::Affine tf_stack=m_tr_stack.top(); // and why is transform argument not used?
    Geom::PathVector pathv = pathv_in * tf_stack; // generates new path, which is a bit slow, but this doesn't have to be performance optimized

    os << "\\newpath\n";

    for(Geom::PathVector::const_iterator it = pathv.begin(); it != pathv.end(); ++it) {

        os << "\\moveto(" << it->initialPoint()[Geom::X] << "," << it->initialPoint()[Geom::Y] << ")\n";

        for(Geom::Path::const_iterator cit = it->begin(); cit != it->end_open(); ++cit) {
            print_2geomcurve(os, *cit);
        }

        if (it->closed()) {
            os << "\\closepath\n";
        }

    }
}

/** Feeds path-creating calls to the cairo context translating them from the PathVector
 *  One must have done cairo_new_path(ct); before calling this function. */
void
feed_pathvector_to_cairo (cairo_t *ct, Geom::PathVector const &pathv)
{
    if (pathv.empty())
        return;

    for(Geom::PathVector::const_iterator it = pathv.begin(); it != pathv.end(); ++it) {
        feed_path_to_cairo(ct, *it);
    }
}

int main(int argc, char **argv) {
    if (argc > 1) {
        SVGPathTestPrinter sink;
        Geom::parse_svg_path(&*argv[1], sink);
        std::cout << "Try real pathsink:" << std::endl;
        Geom::PathVector testpath = Geom::parse_svg_path(&*argv[1]);
        std::cout << "Geom::PathVector length: " << testpath.size() << std::endl;
        if ( !testpath.empty() )
        	std::cout << "Path curves: " << testpath.front().size() << std::endl;
        std::cout << "success!" << std::endl;
    }
    return 0;
};

Geom::OptRect
bounds_exact_transformed(Geom::PathVector const & pv, Geom::Affine const & t)
{
    if (pv.empty())
        return Geom::OptRect();

    Geom::Point initial = pv.front().initialPoint() * t;
    Geom::Rect bbox(initial, initial);        // obtain well defined bbox as starting point to unionWith

    for (Geom::PathVector::const_iterator it = pv.begin(); it != pv.end(); ++it) {
        bbox.expandTo(it->initialPoint() * t);

        // don't loop including closing segment, since that segment can never increase the bbox
        for (Geom::Path::const_iterator cit = it->begin(); cit != it->end_open(); ++cit) {
            Geom::Curve const &c = *cit;

            unsigned order = 0;
            if (Geom::BezierCurve const* b = dynamic_cast<Geom::BezierCurve const*>(&c)) {
                order = b->order();
            }

            if (order == 1) { // line segment
                bbox.expandTo(c.finalPoint() * t);

            // TODO: we can make the case for quadratics faster by degree elevating them to
            // cubic and then taking the bbox of that.

            } else if (order == 3) { // cubic bezier
                Geom::CubicBezier const &cubic_bezier = static_cast<Geom::CubicBezier const&>(c);
                Geom::Point c0 = cubic_bezier[0] * t;
                Geom::Point c1 = cubic_bezier[1] * t;
                Geom::Point c2 = cubic_bezier[2] * t;
                Geom::Point c3 = cubic_bezier[3] * t;
                cubic_bbox(c0[0], c0[1], c1[0], c1[1], c2[0], c2[1], c3[0], c3[1], bbox);
            } else {
                // should handle all not-so-easy curves:
                Geom::Curve *ctemp = cit->transformed(t);
                bbox.unionWith( ctemp->boundsExact());
                delete ctemp;
            }
        }
    }
    //return Geom::bounds_exact(pv * t);
    return bbox;
}

Geom::OptRect
bounds_exact_transformed(Geom::PathVector const & pv, Geom::Affine const & t)
{
    if (pv.empty())
        return Geom::OptRect();

    Geom::Point initial = pv.front().initialPoint() * t;
    Geom::Rect bbox(initial, initial);        // obtain well defined bbox as starting point to unionWith

    for (Geom::PathVector::const_iterator it = pv.begin(); it != pv.end(); ++it) {
        bbox.expandTo(it->initialPoint() * t);

        // don't loop including closing segment, since that segment can never increase the bbox
        for (Geom::Path::const_iterator cit = it->begin(); cit != it->end_open(); ++cit) {
            Geom::Curve const &c = *cit;

            if( is_straight_curve(c) )
            {
                bbox.expandTo( c.finalPoint() * t );
            }
            else if(Geom::CubicBezier const *cubic_bezier = dynamic_cast<Geom::CubicBezier const  *>(&c))
            {
                Geom::Point c0 = (*cubic_bezier)[0] * t;
                Geom::Point c1 = (*cubic_bezier)[1] * t;
                Geom::Point c2 = (*cubic_bezier)[2] * t;
                Geom::Point c3 = (*cubic_bezier)[3] * t;
                cubic_bbox( c0[0], c0[1],
                            c1[0], c1[1],
                            c2[0], c2[1],
                            c3[0], c3[1],
                            bbox );
            }
            else
            {
                // should handle all not-so-easy curves:
                Geom::Curve *ctemp = cit->transformed(t);
                bbox.unionWith( ctemp->boundsExact());
                delete ctemp;
            }
        }
    }
    //return Geom::bounds_exact(pv * t);
    return bbox;
}

/* Calculates...
   and returns ... in *wind and the distance to ... in *dist.
   Returns bounding box in *bbox if bbox!=NULL.
 */
void
pathv_matrix_point_bbox_wind_distance (Geom::PathVector const & pathv, Geom::Affine const &m, Geom::Point const &pt,
                         Geom::Rect *bbox, int *wind, Geom::Coord *dist,
                         Geom::Coord tolerance, Geom::Rect const *viewbox)
{
    if (pathv.empty()) {
        if (wind) *wind = 0;
        if (dist) *dist = Geom::infinity();
        return;
    }

    // remember last point of last curve
    Geom::Point p0(0,0);

    // remembering the start of subpath
    Geom::Point p_start(0,0);
    bool start_set = false;

    for (Geom::PathVector::const_iterator it = pathv.begin(); it != pathv.end(); ++it) {

        if (start_set) { // this is a new subpath
            if (wind && (p0 != p_start)) // for correct fill picking, each subpath must be closed
                geom_line_wind_distance (p0[X], p0[Y], p_start[X], p_start[Y], pt, wind, dist);
        }
        p0 = it->initialPoint() * m;
        p_start = p0;
        start_set = true;
        if (bbox) {
            bbox->expandTo(p0);
        }

        // loop including closing segment if path is closed
        for (Geom::Path::const_iterator cit = it->begin(); cit != it->end_default(); ++cit) {
            geom_curve_bbox_wind_distance(*cit, m, pt, bbox, wind, dist, tolerance, viewbox, p0);
        }
    }

    if (start_set) { 
        if (wind && (p0 != p_start)) // for correct picking, each subpath must be closed
            geom_line_wind_distance (p0[X], p0[Y], p_start[X], p_start[Y], pt, wind, dist);
    }
}

//.........这里部分代码省略.........
                            POINTFX const *p=polyCurve->apfx;
                            POINTFX const *endp=p+polyCurve->cpfx;

                            switch (polyCurve->wType) {
                            case TT_PRIM_LINE:
                                while ( p != endp )
                                    path_builder.lineTo(pointfx_to_nrpoint(*p++, scale));
                                break;

                            case TT_PRIM_QSPLINE:
                                {
                                    g_assert(polyCurve->cpfx >= 2);

                                    // The list of points specifies one or more control points and ends with the end point.
                                    // The intermediate points (on the curve) are the points between the control points.
                                    Geom::Point this_control = pointfx_to_nrpoint(*p++, scale);
                                    while ( p+1 != endp ) { // Process all "midpoints" (all points except the last)
                                        Geom::Point new_control = pointfx_to_nrpoint(*p++, scale);
                                        path_builder.quadTo(this_control, (new_control+this_control)/2);
                                        this_control = new_control;
                                    }
                                    Geom::Point end = pointfx_to_nrpoint(*p++, scale);
                                    path_builder.quadTo(this_control, end);
                                }
                                break;

                            case 3:  // TT_PRIM_CSPLINE
                                g_assert(polyCurve->cpfx % 3 == 0);
                                while ( p != endp ) {
                                    path_builder.curveTo(pointfx_to_nrpoint(p[0], scale),
                                                         pointfx_to_nrpoint(p[1], scale),
                                                         pointfx_to_nrpoint(p[2], scale));
                                    p += 3;
                                }
                                break;
                            }
                            curveOffset += sizeof(TTPOLYCURVE)+sizeof(POINTFX)*(polyCurve->cpfx-1);
                        }
                    }
                    polyOffset += polyHeader->cb;
                }
                doAdd=true;
            }
            delete [] buffer;
        }
#else
        if (FT_Load_Glyph (theFace, glyph_id, FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING | FT_LOAD_NO_BITMAP)) {
            // shit happened
        } else {
            if ( FT_HAS_HORIZONTAL(theFace) ) {
                n_g.h_advance=((double)theFace->glyph->metrics.horiAdvance)/((double)theFace->units_per_EM);
                n_g.h_width=((double)theFace->glyph->metrics.width)/((double)theFace->units_per_EM);
            } else {
                n_g.h_width=n_g.h_advance=((double)(theFace->bbox.xMax-theFace->bbox.xMin))/((double)theFace->units_per_EM);
            }
            if ( FT_HAS_VERTICAL(theFace) ) {
                n_g.v_advance=((double)theFace->glyph->metrics.vertAdvance)/((double)theFace->units_per_EM);
                n_g.v_width=((double)theFace->glyph->metrics.height)/((double)theFace->units_per_EM);
            } else {
                n_g.v_width=n_g.v_advance=((double)theFace->height)/((double)theFace->units_per_EM);
            }
            if ( theFace->glyph->format == ft_glyph_format_outline ) {
                FT_Outline_Funcs ft2_outline_funcs = {
                    ft2_move_to,
                    ft2_line_to,
                    ft2_conic_to,
                    ft2_cubic_to,
                    0, 0
                };
                FT2GeomData user(path_builder, 1.0/((double)theFace->units_per_EM));
                FT_Outline_Decompose (&theFace->glyph->outline, &ft2_outline_funcs, &user);
            }
            doAdd=true;
        }
#endif
        path_builder.finish();

        if ( doAdd ) {
            Geom::PathVector pv = path_builder.peek();
            // close all paths
            for (Geom::PathVector::iterator i = pv.begin(); i != pv.end(); ++i) {
                i->close();
            }
            if ( !pv.empty() ) {
                n_g.pathvector = new Geom::PathVector(pv);
                Geom::OptRect bounds = bounds_exact(*n_g.pathvector);
                if (bounds) {
                    n_g.bbox[0] = bounds->left();
                    n_g.bbox[1] = bounds->top();
                    n_g.bbox[2] = bounds->right();
                    n_g.bbox[3] = bounds->bottom();
                }
            }
            glyphs[nbGlyph]=n_g;
            id_to_no[glyph_id]=nbGlyph;
            nbGlyph++;
        }
    } else {
    }
}