/* * Can be called recursively. * If optimize_stroke == false, the view Rect is not used. */ static void feed_curve_to_cairo(cairo_t *cr, Geom::Curve const &c, Geom::Affine const & trans, Geom::Rect view, bool optimize_stroke) { if( is_straight_curve(c) ) { Geom::Point end_tr = c.finalPoint() * trans; if (!optimize_stroke) { cairo_line_to(cr, end_tr[0], end_tr[1]); } else { Geom::Rect swept(c.initialPoint()*trans, end_tr); if (swept.intersects(view)) { cairo_line_to(cr, end_tr[0], end_tr[1]); } else { cairo_move_to(cr, end_tr[0], end_tr[1]); } } } else if(Geom::QuadraticBezier const *quadratic_bezier = dynamic_cast<Geom::QuadraticBezier const*>(&c)) { std::vector<Geom::Point> points = quadratic_bezier->points(); points[0] *= trans; points[1] *= trans; points[2] *= trans; Geom::Point b1 = points[0] + (2./3) * (points[1] - points[0]); Geom::Point b2 = b1 + (1./3) * (points[2] - points[0]); if (!optimize_stroke) { cairo_curve_to(cr, b1[0], b1[1], b2[0], b2[1], points[2][0], points[2][1]); } else { Geom::Rect swept(points[0], points[2]); swept.expandTo(points[1]); if (swept.intersects(view)) { cairo_curve_to(cr, b1[0], b1[1], b2[0], b2[1], points[2][0], points[2][1]); } else { cairo_move_to(cr, points[2][0], points[2][1]); } } } else if(Geom::CubicBezier const *cubic_bezier = dynamic_cast<Geom::CubicBezier const*>(&c)) { std::vector<Geom::Point> points = cubic_bezier->points(); //points[0] *= trans; // don't do this one here for fun: it is only needed for optimized strokes points[1] *= trans; points[2] *= trans; points[3] *= trans; if (!optimize_stroke) { cairo_curve_to(cr, points[1][0], points[1][1], points[2][0], points[2][1], points[3][0], points[3][1]); } else { points[0] *= trans; // didn't transform this point yet Geom::Rect swept(points[0], points[3]); swept.expandTo(points[1]); swept.expandTo(points[2]); if (swept.intersects(view)) { cairo_curve_to(cr, points[1][0], points[1][1], points[2][0], points[2][1], points[3][0], points[3][1]); } else { cairo_move_to(cr, points[3][0], points[3][1]); } } } // else if(Geom::SVGEllipticalArc const *svg_elliptical_arc = dynamic_cast<Geom::SVGEllipticalArc *>(c)) { // //TODO: get at the innards and spit them out to cairo // } else { //this case handles sbasis as well as all other curve types Geom::Path sbasis_path = Geom::cubicbezierpath_from_sbasis(c.toSBasis(), 0.1); //recurse to convert the new path resulting from the sbasis to svgd for(Geom::Path::iterator iter = sbasis_path.begin(); iter != sbasis_path.end(); ++iter) { feed_curve_to_cairo(cr, *iter, trans, view, optimize_stroke); } } }
/* * Can be called recursively. * If optimize_stroke == false, the view Rect is not used. */ static void feed_curve_to_cairo(cairo_t *cr, Geom::Curve const &c, Geom::Affine const & trans, Geom::Rect view, bool optimize_stroke) { using Geom::X; using Geom::Y; unsigned order = 0; if (Geom::BezierCurve const* b = dynamic_cast<Geom::BezierCurve const*>(&c)) { order = b->order(); } // handle the three typical curve cases switch (order) { case 1: { Geom::Point end_tr = c.finalPoint() * trans; if (!optimize_stroke) { cairo_line_to(cr, end_tr[0], end_tr[1]); } else { Geom::Rect swept(c.initialPoint()*trans, end_tr); if (swept.intersects(view)) { cairo_line_to(cr, end_tr[0], end_tr[1]); } else { cairo_move_to(cr, end_tr[0], end_tr[1]); } } } break; case 2: { Geom::QuadraticBezier const *quadratic_bezier = static_cast<Geom::QuadraticBezier const*>(&c); std::vector<Geom::Point> points = quadratic_bezier->controlPoints(); points[0] *= trans; points[1] *= trans; points[2] *= trans; // degree-elevate to cubic Bezier, since Cairo doesn't do quadratic Beziers Geom::Point b1 = points[0] + (2./3) * (points[1] - points[0]); Geom::Point b2 = b1 + (1./3) * (points[2] - points[0]); if (!optimize_stroke) { cairo_curve_to(cr, b1[X], b1[Y], b2[X], b2[Y], points[2][X], points[2][Y]); } else { Geom::Rect swept(points[0], points[2]); swept.expandTo(points[1]); if (swept.intersects(view)) { cairo_curve_to(cr, b1[X], b1[Y], b2[X], b2[Y], points[2][X], points[2][Y]); } else { cairo_move_to(cr, points[2][X], points[2][Y]); } } } break; case 3: { Geom::CubicBezier const *cubic_bezier = static_cast<Geom::CubicBezier const*>(&c); std::vector<Geom::Point> points = cubic_bezier->controlPoints(); //points[0] *= trans; // don't do this one here for fun: it is only needed for optimized strokes points[1] *= trans; points[2] *= trans; points[3] *= trans; if (!optimize_stroke) { cairo_curve_to(cr, points[1][X], points[1][Y], points[2][X], points[2][Y], points[3][X], points[3][Y]); } else { points[0] *= trans; // didn't transform this point yet Geom::Rect swept(points[0], points[3]); swept.expandTo(points[1]); swept.expandTo(points[2]); if (swept.intersects(view)) { cairo_curve_to(cr, points[1][X], points[1][Y], points[2][X], points[2][Y], points[3][X], points[3][Y]); } else { cairo_move_to(cr, points[3][X], points[3][Y]); } } } break; default: { if (Geom::EllipticalArc const *a = dynamic_cast<Geom::EllipticalArc const*>(&c)) { //if (!optimize_stroke || a->boundsFast().intersects(view)) { Geom::Affine xform = a->unitCircleTransform() * trans; Geom::Point ang(a->initialAngle().radians(), a->finalAngle().radians()); // Apply the transformation to the current context cairo_matrix_t cm; cm.xx = xform[0]; cm.xy = xform[2]; cm.x0 = xform[4]; cm.yx = xform[1]; cm.yy = xform[3]; cm.y0 = xform[5]; cairo_save(cr); cairo_transform(cr, &cm); // Draw the circle if (a->sweep()) { cairo_arc(cr, 0, 0, 1, ang[0], ang[1]); } else { cairo_arc_negative(cr, 0, 0, 1, ang[0], ang[1]); } // Revert the current context cairo_restore(cr); //} else { // Geom::Point f = a->finalPoint() * trans; // cairo_move_to(cr, f[X], f[Y]); //} } else { // handles sbasis as well as all other curve types // this is very slow Geom::Path sbasis_path = Geom::cubicbezierpath_from_sbasis(c.toSBasis(), 0.1); // recurse to convert the new path resulting from the sbasis to svgd for (Geom::Path::iterator iter = sbasis_path.begin(); iter != sbasis_path.end(); ++iter) { feed_curve_to_cairo(cr, *iter, trans, view, optimize_stroke); } } } break; } }