C++ SPCurve::copy方法代码示例

// Create path for rendering shape on screen
void SPGenericEllipse::set_shape()
{
    // std::cout << "SPGenericEllipse::set_shape: Entrance" << std::endl;
    if (hasBrokenPathEffect()) {
        g_warning("The ellipse shape has unknown LPE on it! Convert to path to make it editable preserving the appearance; editing it as ellipse will remove the bad LPE");

        if (this->getRepr()->attribute("d")) {
            // unconditionally read the curve from d, if any, to preserve appearance
            Geom::PathVector pv = sp_svg_read_pathv(this->getRepr()->attribute("d"));
            SPCurve *cold = new SPCurve(pv);
            this->setCurveInsync(cold, TRUE);
            cold->unref();
        }

        return;
    }
    if (Geom::are_near(this->rx.computed, 0) || Geom::are_near(this->ry.computed, 0)) {
        return;
    }

    this->normalize();

    SPCurve *curve = NULL;

    // For simplicity, we use a circle with center (0, 0) and radius 1 for our calculations.
    Geom::Circle circle(0, 0, 1);

    if (!this->_isSlice()) {
        start = 0.0;
        end = 2.0*M_PI;
    }
    double incr = end - start; // arc angle
    if (incr < 0.0) incr += 2.0*M_PI;    

    int numsegs = 1 + int(incr*2.0/M_PI); // number of arc segments
    if (numsegs > 4) numsegs = 4;

    incr = incr/numsegs; // limit arc angle to less than 90 degrees
    Geom::Path path(Geom::Point::polar(start));
    Geom::EllipticalArc* arc;
    for (int seg = 0; seg < numsegs; seg++) {
        arc = circle.arc(Geom::Point::polar(start + seg*incr), Geom::Point::polar(start + (seg + 0.5)*incr), Geom::Point::polar(start + (seg + 1.0)*incr));
        path.append(*arc);
        delete arc;
    }
    Geom::PathBuilder pb;
    pb.append(path);
    if (this->_isSlice() && this->_closed) {
        pb.lineTo(Geom::Point(0, 0));
    }
    if (this->_closed) {
        pb.closePath();
    } else {
        pb.flush();
    }
    curve = new SPCurve(pb.peek());

    // gchar *str = sp_svg_write_path(curve->get_pathvector());
    // std::cout << "  path: " << str << std::endl;
    // g_free(str);

    // Stretching / moving the calculated shape to fit the actual dimensions.
    Geom::Affine aff = Geom::Scale(rx.computed, ry.computed) * Geom::Translate(cx.computed, cy.computed);
    curve->transform(aff);

    /* Reset the shape's curve to the "original_curve"
     * This is very important for LPEs to work properly! (the bbox might be recalculated depending on the curve in shape)*/
    this->setCurveInsync(curve, TRUE);
    this->setCurveBeforeLPE(curve);

    if (hasPathEffect() && pathEffectsEnabled()) {
        SPCurve *c_lpe = curve->copy();
        bool success = this->performPathEffect(c_lpe);

        if (success) {
            this->setCurveInsync(c_lpe, TRUE);
        }

        c_lpe->unref();
    }

    curve->unref();
    // std::cout << "SPGenericEllipse::set_shape: Exit" << std::endl;
}

void SPStar::set_shape() {
    // perhaps we should convert all our shapes into LPEs without source path
    // and with knotholders for parameters, then this situation will be handled automatically
    // by disabling the entire stack (including the shape LPE)
    if (hasBrokenPathEffect()) {
        g_warning ("The star shape has unknown LPE on it! Convert to path to make it editable preserving the appearance; editing it as star will remove the bad LPE");

        if (this->getRepr()->attribute("d")) {
            // unconditionally read the curve from d, if any, to preserve appearance
            Geom::PathVector pv = sp_svg_read_pathv(this->getRepr()->attribute("d"));
            SPCurve *cold = new SPCurve(pv);
            this->setCurveInsync( cold, TRUE);
            this->setCurveBeforeLPE(cold);
            cold->unref();
        }

        return;
    }

    SPCurve *c = new SPCurve ();

    bool not_rounded = (fabs (this->rounded) < 1e-4);

    // note that we pass randomized=true to sp_star_get_xy, because the curve must be randomized;
    // other places that call that function (e.g. the knotholder) need the exact point

    // draw 1st segment
    c->moveto(sp_star_get_xy (this, SP_STAR_POINT_KNOT1, 0, true));

    if (this->flatsided == false) {
        if (not_rounded) {
            c->lineto(sp_star_get_xy (this, SP_STAR_POINT_KNOT2, 0, true));
        } else {
            c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, NEXT),
                sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, 0, PREV),
                sp_star_get_xy (this, SP_STAR_POINT_KNOT2, 0, true));
        }
    }

    // draw all middle segments
    for (gint i = 1; i < sides; i++) {
        if (not_rounded) {
            c->lineto(sp_star_get_xy (this, SP_STAR_POINT_KNOT1, i, true));
        } else {
            if (this->flatsided == false) {
                c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, i - 1, NEXT),
                        sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, PREV),
                        sp_star_get_xy (this, SP_STAR_POINT_KNOT1, i, true));
            } else {
                c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i - 1, NEXT),
                        sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, PREV),
                        sp_star_get_xy (this, SP_STAR_POINT_KNOT1, i, true));
            }
        }

        if (this->flatsided == false) {
            if (not_rounded) {
                       c->lineto(sp_star_get_xy (this, SP_STAR_POINT_KNOT2, i, true));
            } else {
                c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, NEXT),
                    sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, i, PREV),
                    sp_star_get_xy (this, SP_STAR_POINT_KNOT2, i, true));
            }
        }
    }

    // draw last segment
	if (!not_rounded) {
		if (this->flatsided == false) {
			c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, sides - 1, NEXT),
				sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, PREV),
				sp_star_get_xy (this, SP_STAR_POINT_KNOT1, 0, true));
		} else {
			c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, sides - 1, NEXT),
				sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, PREV),
				sp_star_get_xy (this, SP_STAR_POINT_KNOT1, 0, true));
		}
	}

    c->closepath();

    /* Reset the shape'scurve to the "original_curve"
     * This is very important for LPEs to work properly! (the bbox might be recalculated depending on the curve in shape)*/
    this->setCurveInsync( c, TRUE);
    this->setCurveBeforeLPE( c );

    if (hasPathEffect() && pathEffectsEnabled()) {
        SPCurve *c_lpe = c->copy();
        bool success = this->performPathEffect(c_lpe);

        if (success) {
            this->setCurveInsync( c_lpe, TRUE);
        } 

        c_lpe->unref();
    }

    c->unref();
}

void Box3DSide::set_shape() {
    if (!this->document->getRoot()) {
        // avoid a warning caused by sp_document_height() (which is called from sp_item_i2d_affine() below)
        // when reading a file containing 3D boxes
        return;
    }

    SPObject *parent = this->parent;

    if (!SP_IS_BOX3D(parent)) {
        g_warning("Parent of 3D box side is not a 3D box.\n");
        return;
    }

    SPBox3D *box = SP_BOX3D(parent);

    Persp3D *persp = box3d_side_perspective(this);

    if (!persp) {
        return;
    }

    // TODO: Draw the correct quadrangle here
    //       To do this, determine the perspective of the box, the orientation of the side (e.g., XY-FRONT)
    //       compute the coordinates of the corners in P^3, project them onto the canvas, and draw the
    //       resulting path.

    unsigned int corners[4];
    box3d_side_compute_corner_ids(this, corners);

    SPCurve *c = new SPCurve();

    if (!box3d_get_corner_screen(box, corners[0]).isFinite() ||
        !box3d_get_corner_screen(box, corners[1]).isFinite() ||
        !box3d_get_corner_screen(box, corners[2]).isFinite() ||
        !box3d_get_corner_screen(box, corners[3]).isFinite() )
    {
        g_warning ("Trying to draw a 3D box side with invalid coordinates.\n");
        return;
    }

    c->moveto(box3d_get_corner_screen(box, corners[0]));
    c->lineto(box3d_get_corner_screen(box, corners[1]));
    c->lineto(box3d_get_corner_screen(box, corners[2]));
    c->lineto(box3d_get_corner_screen(box, corners[3]));
    c->closepath();

    /* Reset the this'scurve to the "original_curve"
     * This is very important for LPEs to work properly! (the bbox might be recalculated depending on the curve in shape)*/
    this->setCurveInsync( c, TRUE);

    if (hasPathEffect() && pathEffectsEnabled()) {
        SPCurve *c_lpe = c->copy();
        bool success = this->performPathEffect(c_lpe);

        if (success) {
            this->setCurveInsync(c_lpe, TRUE);
        }

        c_lpe->unref();
    }

    c->unref();
}