Code

Super duper mega (fun!) commit: replaced encoding=utf-8 with fileencoding=utf-8 in...
[inkscape.git] / src / live_effects / lpe-powerstroke.cpp
index 447b8566410cab3c0ff44986cd31cd1a8d902810..5dc170e84f106abfe09d0e30d62e9c26e8440591 100644 (file)
@@ -19,6 +19,7 @@
 #include <2geom/piecewise.h>
 #include <2geom/sbasis-geometric.h>
 #include <2geom/transforms.h>
+#include <2geom/bezier-utils.h>
 
 
 /// @TODO  Move this to 2geom
@@ -44,12 +45,12 @@ public:
     virtual ~Linear() {};
 
     virtual Path interpolateToPath(std::vector<Point> points) {
-        Path strokepath;
-        strokepath.start( points.at(0) );
+        Path path;
+        path.start( points.at(0) );
         for (unsigned int i = 1 ; i < points.size(); ++i) {
-            strokepath.appendNew<Geom::LineSegment>(points.at(i));
+            path.appendNew<Geom::LineSegment>(points.at(i));
         }
-        return strokepath;
+        return path;
     };
 
 private:
@@ -57,6 +58,68 @@ private:
     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
 
@@ -70,6 +133,8 @@ LPEPowerStroke::LPEPowerStroke(LivePathEffectObject *lpeobject) :
 {
     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) );
 }
@@ -84,10 +149,10 @@ void
 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);
 }
 
@@ -102,41 +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() + 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) {
-        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+1) = Geom::Point(t, offset);
-    }
+    offset_points.set_pwd2(pwd2_in);
+
+    Piecewise<D2<SBasis> > der = unitVector(derivative(pwd2_in));
+    Piecewise<D2<SBasis> > n = rot90(der);
+    offset_points.set_pwd2_normal(n);
 
-    if (sort_points) {
-        sort(ts.begin(), ts.end(), compare_offsets);
+        // 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;
     }
 
-    // create stroke path where points (x,y) = (t, offset)
-    Geom::Interpolate::Linear interpolator;
-    Path strokepath = interpolator.interpolateToPath(ts);
-    Path mirroredpath = strokepath.reverse() * Geom::Scale(1,-1);
-    strokepath.append(mirroredpath, Geom::Path::STITCH_DISCONTINUOUS);
-    strokepath.close();
+    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);
+        }
 
-    D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(strokepath.toPwSb());
-    Piecewise<SBasis> x = Piecewise<SBasis>(patternd2[0]);
-    Piecewise<SBasis> y = Piecewise<SBasis>(patternd2[1]);
+        if (sort_points) {
+            sort(ts.begin(), ts.end(), compare_offsets);
+        }
 
-    Piecewise<D2<SBasis> > der = unitVector(derivative(pwd2_in));
-    Piecewise<D2<SBasis> > n   = rot90(der);
+        // 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();
+
+        D2<Piecewise<SBasis> > patternd2 = make_cuts_independent(strokepath.toPwSb());
+        Piecewise<SBasis> x = Piecewise<SBasis>(patternd2[0]);
+        Piecewise<SBasis> y = Piecewise<SBasis>(patternd2[1]);
 
-//    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);
+        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;
 }
 
@@ -154,4 +259,4 @@ LPEPowerStroke::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const &
   fill-column:99
   End:
 */
-// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :