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index cb45e0518faba0f4d4052534c44fc070ce680444..6109ea498f77ea546af3c4be4faf59e353ad4b44 100644 (file)
#include <2geom/path.h>
#include <2geom/piecewise.h>
#include <2geom/sbasis-geometric.h>
-#include <2geom/svg-elliptical-arc.h>
#include <2geom/transforms.h>
+#include <2geom/bezier-utils.h>
+
+
+/// @TODO Move this to 2geom
+namespace Geom {
+namespace Interpolate {
+
+class Interpolator {
+public:
+ Interpolator() {};
+ virtual ~Interpolator() {};
+
+// virtual Piecewise<D2<SBasis> > interpolateToPwD2Sb(std::vector<Point> points) = 0;
+ virtual Path interpolateToPath(std::vector<Point> points) = 0;
+
+private:
+ Interpolator(const Interpolator&);
+ Interpolator& operator=(const Interpolator&);
+};
+
+class Linear : public Interpolator {
+public:
+ Linear() {};
+ virtual ~Linear() {};
+
+ virtual Path interpolateToPath(std::vector<Point> points) {
+ Path path;
+ path.start( points.at(0) );
+ for (unsigned int i = 1 ; i < points.size(); ++i) {
+ path.appendNew<Geom::LineSegment>(points.at(i));
+ }
+ return path;
+ };
+
+private:
+ Linear(const Linear&);
+ Linear& operator=(const Linear&);
+};
+
+// this class is terrible
+class CubicBezierFit : public Interpolator {
+public:
+ CubicBezierFit() {};
+ virtual ~CubicBezierFit() {};
+
+ virtual Path interpolateToPath(std::vector<Point> points) {
+ unsigned int n_points = points.size();
+ // worst case gives us 2 segment per point
+ int max_segs = 8*n_points;
+ Geom::Point * b = g_new(Geom::Point, max_segs);
+ Geom::Point * points_array = g_new(Geom::Point, 4*n_points);
+ for (unsigned i = 0; i < n_points; ++i) {
+ points_array[i] = points.at(i);
+ }
+
+ double tolerance_sq = 0; // this value is just a random guess
+
+ int const n_segs = Geom::bezier_fit_cubic_r(b, points_array, n_points,
+ tolerance_sq, max_segs);
+
+ Geom::Path fit;
+ if ( n_segs > 0)
+ {
+ fit.start(b[0]);
+ for (int c = 0; c < n_segs; c++) {
+ fit.appendNew<Geom::CubicBezier>(b[4*c+1], b[4*c+2], b[4*c+3]);
+ }
+ }
+ g_free(b);
+ g_free(points_array);
+ return fit;
+ };
+
+private:
+ CubicBezierFit(const CubicBezierFit&);
+ CubicBezierFit& operator=(const CubicBezierFit&);
+};
+
+/// @todo invent name for this class
+class CubicBezierJohan : public Interpolator {
+public:
+ CubicBezierJohan() {};
+ virtual ~CubicBezierJohan() {};
+
+ virtual Path interpolateToPath(std::vector<Point> points) {
+ Path fit;
+ fit.start(points.at(0));
+ for (unsigned int i = 1; i < points.size(); ++i) {
+ Point p0 = points.at(i-1);
+ Point p1 = points.at(i);
+ Point dx = Point(p1[X] - p0[X], 0);
+ fit.appendNew<CubicBezier>(p0+0.2*dx, p1-0.2*dx, p1);
+ }
+ return fit;
+ };
+
+private:
+ CubicBezierJohan(const CubicBezierJohan&);
+ CubicBezierJohan& operator=(const CubicBezierJohan&);
+};
+
+} //namespace Interpolate
+} //namespace Geom
namespace Inkscape {
namespace LivePathEffect {
{
show_orig_path = true;
+ /// @todo offset_points are initialized with empty path, is that bug-save?
+
registerParameter( dynamic_cast<Parameter *>(&offset_points) );
registerParameter( dynamic_cast<Parameter *>(&sort_points) );
}
LPEPowerStroke::doOnApply(SPLPEItem *lpeitem)
{
std::vector<Geom::Point> points;
- points.push_back( *(SP_SHAPE(lpeitem)->curve->first_point()) );
- Geom::Path const *path = SP_SHAPE(lpeitem)->curve->first_path();
- points.push_back( path->pointAt(path->size()/2) );
- points.push_back( *(SP_SHAPE(lpeitem)->curve->last_point()) );
+ Geom::Path::size_type size = SP_SHAPE(lpeitem)->curve->get_pathvector().front().size_open();
+ points.push_back( Geom::Point(0,0) );
+ points.push_back( Geom::Point(0.5*size,0) );
+ points.push_back( Geom::Point(size,0) );
offset_points.param_set_and_write_new_value(points);
}
-static void append_half_circle(Geom::Piecewise<Geom::D2<Geom::SBasis> > &pwd2,
- Geom::Point const center, Geom::Point const &dir) {
- using namespace Geom;
-
- double r = L2(dir);
- SVGEllipticalArc cap(center + dir, r, r, angle_between(Point(1,0), dir), false, false, center - dir);
- Piecewise<D2<SBasis> > cap_pwd2(cap.toSBasis());
- pwd2.continuousConcat(cap_pwd2);
-}
-
static bool compare_offsets (Geom::Point first, Geom::Point second)
{
- return first[Geom::X] <= second[Geom::X];
+ return first[Geom::X] < second[Geom::X];
}
@@ -73,44 +167,81 @@ LPEPowerStroke::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const &
{
using namespace Geom;
- // perhaps use std::list instead of std::vector?
- std::vector<Geom::Point> ts(offset_points.data().size());
+ offset_points.set_pwd2(pwd2_in);
- for (unsigned int i; i < ts.size(); ++i) {
- double t = nearest_point(offset_points.data().at(i), pwd2_in);
- double offset = L2(pwd2_in.valueAt(t) - offset_points.data().at(i));
- ts.at(i) = Geom::Point(t, offset);
- }
- if (sort_points) {
- sort(ts.begin(), ts.end(), compare_offsets);
- }
+ Piecewise<D2<SBasis> > der = unitVector(derivative(pwd2_in));
+ Piecewise<D2<SBasis> > n = rot90(der);
+ offset_points.set_pwd2_normal(n);
- // create stroke path where points (x,y) = (t, offset)
- Path strokepath;
- strokepath.start( Point(pwd2_in.domain().min(),0) );
- for (unsigned int i = 0 ; i < ts.size(); ++i) {
- strokepath.appendNew<Geom::LineSegment>(ts.at(i));
+ // see if we should treat the path as being closed.
+ bool closed_path = false;
+ if ( are_near(pwd2_in.firstValue(), pwd2_in.lastValue()) ) {
+ closed_path = true;
}
- strokepath.appendNew<Geom::LineSegment>( Point(pwd2_in.domain().max(), 0) );
- for (unsigned int i = 0; i < ts.size(); ++i) {
- Geom::Point temp = ts.at(ts.size() - 1 - i);
- strokepath.appendNew<Geom::LineSegment>( Geom::Point(temp[X], - temp[Y]) );
- }
- strokepath.close();
- D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(strokepath.toPwSb());
- Piecewise<SBasis> x = Piecewise<SBasis>(patternd2[0]);
- Piecewise<SBasis> y = Piecewise<SBasis>(patternd2[1]);
+ Piecewise<D2<SBasis> > output;
+ if (!closed_path) {
+ // perhaps use std::list instead of std::vector?
+ std::vector<Geom::Point> ts(offset_points.data().size() + 2);
+ // first and last point coincide with input path (for now at least)
+ ts.front() = Point(pwd2_in.domain().min(),0);
+ ts.back() = Point(pwd2_in.domain().max(),0);
+ for (unsigned int i = 0; i < offset_points.data().size(); ++i) {
+ ts.at(i+1) = offset_points.data().at(i);
+ }
- Piecewise<D2<SBasis> > der = unitVector(derivative(pwd2_in));
- Piecewise<D2<SBasis> > n = rot90(der);
+ if (sort_points) {
+ sort(ts.begin(), ts.end(), compare_offsets);
+ }
+
+ // create stroke path where points (x,y) := (t, offset)
+ Geom::Interpolate::CubicBezierJohan interpolator;
+ Path strokepath = interpolator.interpolateToPath(ts);
+ Path mirroredpath = strokepath.reverse() * Geom::Scale(1,-1);
+
+ strokepath.append(mirroredpath, Geom::Path::STITCH_DISCONTINUOUS);
+ strokepath.close();
-// output = pwd2_in + n * offset;
-// append_half_circle(output, pwd2_in.lastValue(), n.lastValue() * offset);
-// output.continuousConcat(reverse(pwd2_in - n * offset));
-// append_half_circle(output, pwd2_in.firstValue(), -n.firstValue() * offset);
+ D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(strokepath.toPwSb());
+ Piecewise<SBasis> x = Piecewise<SBasis>(patternd2[0]);
+ Piecewise<SBasis> y = Piecewise<SBasis>(patternd2[1]);
+
+ output = compose(pwd2_in,x) + y*compose(n,x);
+ } else {
+ // path is closed
+
+ // perhaps use std::list instead of std::vector?
+ std::vector<Geom::Point> ts = offset_points.data();
+ if (sort_points) {
+ sort(ts.begin(), ts.end(), compare_offsets);
+ }
+ // add extra points for interpolation between first and last point
+ Point first_point = ts.front();
+ Point last_point = ts.back();
+ ts.insert(ts.begin(), last_point - Point(pwd2_in.domain().extent() ,0));
+ ts.push_back( first_point + Point(pwd2_in.domain().extent() ,0) );
+ // create stroke path where points (x,y) := (t, offset)
+ Geom::Interpolate::CubicBezierJohan interpolator;
+ Path strokepath = interpolator.interpolateToPath(ts);
+
+ // output 2 separate paths
+ D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(strokepath.toPwSb());
+ Piecewise<SBasis> x = Piecewise<SBasis>(patternd2[0]);
+ Piecewise<SBasis> y = Piecewise<SBasis>(patternd2[1]);
+ // find time values for which x lies outside path domain
+ // and only take portion of x and y that lies within those time values
+ std::vector< double > rtsmin = roots (x - pwd2_in.domain().min());
+ std::vector< double > rtsmax = roots (x - pwd2_in.domain().max());
+ if ( !rtsmin.empty() && !rtsmax.empty() ) {
+ x = portion(x, rtsmin.at(0), rtsmax.at(0));
+ y = portion(y, rtsmin.at(0), rtsmax.at(0));
+ }
+ output = compose(pwd2_in,x) + y*compose(n,x);
+ x = reverse(x);
+ y = reverse(y);
+ output.concat(compose(pwd2_in,x) - y*compose(n,x));
+ }
- Piecewise<D2<SBasis> > output = compose(pwd2_in,x) + y*compose(n,x);
return output;
}