Code

Packaging. New Brazilian Portuguese NSH file. Set trunk package date to 2011.
[inkscape.git] / src / live_effects / lpe-sketch.cpp
index 9b49122fe3b4b322abd3fcaf87b2e05fc92dd00a..f03bac811ef530278f04e6baf1e716cda3707399 100644 (file)
-#define INKSCAPE_LPE_SKETCH_CPP\r
-/** \file\r
- * LPE <sketch> implementation\r
- */\r
-/*\r
- * Authors:\r
- *   Johan Engelen\r
-*\r
-* Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>\r
- *\r
- * Released under GNU GPL, read the file 'COPYING' for more information\r
- */\r
-\r
-#include "live_effects/lpe-sketch.h"\r
-#include "display/curve.h"\r
-#include <libnr/n-art-bpath.h>\r
-\r
-// You might need to include other 2geom files. You can add them here:\r
-#include <2geom/path.h>\r
-#include <2geom/sbasis.h>\r
-#include <2geom/sbasis-geometric.h>\r
-#include <2geom/bezier-to-sbasis.h>\r
-#include <2geom/sbasis-to-bezier.h>\r
-#include <2geom/d2.h>\r
-#include <2geom/sbasis-math.h>\r
-#include <2geom/piecewise.h>\r
-#include <2geom/crossing.h>\r
-#include <2geom/path-intersection.h>\r
-\r
-namespace Inkscape {\r
-namespace LivePathEffect {\r
-\r
-LPESketch::LPESketch(LivePathEffectObject *lpeobject) :\r
-    Effect(lpeobject),\r
-    // initialise your parameters here:\r
-    //testpointA(_("Test Point A"), _("Test A"), "ptA", &wr, this, Geom::Point(100,100)),\r
-    nbiter_approxstrokes(_("Nb of iterations"), _("Draw that many approximating strokes sequences."), "nbiter_approxstrokes", &wr, this, 5),\r
-    strokelength(_("Max stroke length"), _("Maximal length of approximated strokes."), "strokelength", &wr, this, 100.),\r
-    strokelength_rdm(_("Randomness"), _("Random variation of stroke length (relative to max. length)."), "strokelength_rdm", &wr, this, .3),\r
-    strokeoverlap(_("Max. overlap"), _("How much successive strokes should overlap (relative to max. length)."), "strokeoverlap", &wr, this, .3),\r
-    strokeoverlap_rdm(_("Randomness"), _("Random variation of overlap (relative to max. overlap)"), "strokeoverlap_rdm", &wr, this, .3),\r
-    ends_tolerance(_("Max. ends tolerance"), _("Max. distance between original and approximated paths ends (relative to max. length)."), "ends_tolerance", &wr, this, .1),\r
-    parallel_offset(_("Average offset"), _("Average distance to original stroke(try 0.)."), "parallel_offset", &wr, this, 5.),\r
-    tremble_size(_("Max. tremble"), _("Maximal tremble magnitude."), "tremble_size", &wr, this, 5.),\r
-    tremble_frequency(_("Tremble frequency"), _("Typical nb of tremble 'period' in a stroke."), "tremble_frequency", &wr, this, 1.),\r
-    nbtangents(_("Nb of construction Lines"), _("How many construction lines (tangents) to draw?"), "nbtangents", &wr, this, 5),\r
-    tgtscale(_("Scale"), _("Scale factor relating curvature and length of construction lines(try 5*avarage offset) )"), "tgtscale", &wr, this, 10.0),\r
-    tgtlength(_("Max. length"), _("Max. length of construction lines."), "tgtlength", &wr, this, 100.0),\r
-    tgtlength_rdm(_("Randomness"), _("Random variation of construction lines length."), "tgtlength_rdm", &wr, this, .3)\r
-{\r
-    // register all your parameters here, so Inkscape knows which parameters this effect has:\r
-    //Add some comment in the UI:  *warning* the precise output of this effect might change in future releases!\r
-    //convert to path if you want to keep exact output unchanged in future releases...\r
-    //registerParameter( dynamic_cast<Parameter *>(&testpointA) );\r
-    registerParameter( dynamic_cast<Parameter *>(&nbiter_approxstrokes) );\r
-    registerParameter( dynamic_cast<Parameter *>(&strokelength) );\r
-    registerParameter( dynamic_cast<Parameter *>(&strokelength_rdm) );\r
-    registerParameter( dynamic_cast<Parameter *>(&strokeoverlap) );\r
-    registerParameter( dynamic_cast<Parameter *>(&strokeoverlap_rdm) );\r
-    registerParameter( dynamic_cast<Parameter *>(&ends_tolerance) );\r
-    registerParameter( dynamic_cast<Parameter *>(&parallel_offset) );\r
-    registerParameter( dynamic_cast<Parameter *>(&tremble_size) );\r
-    registerParameter( dynamic_cast<Parameter *>(&tremble_frequency) );\r
-    registerParameter( dynamic_cast<Parameter *>(&nbtangents) );\r
-    registerParameter( dynamic_cast<Parameter *>(&tgtscale) );\r
-    registerParameter( dynamic_cast<Parameter *>(&tgtlength) );\r
-    registerParameter( dynamic_cast<Parameter *>(&tgtlength_rdm) );\r
-\r
-\r
-    nbiter_approxstrokes.param_make_integer();\r
-    nbiter_approxstrokes.param_set_range(0, NR_HUGE);\r
-    strokelength.param_set_range(1, NR_HUGE);\r
-    strokelength.param_set_increments(1., 5.);\r
-    strokelength_rdm.param_set_range(0, 1.);\r
-    strokeoverlap.param_set_range(0, 1.);\r
-    strokeoverlap.param_set_increments(0.1, 0.30);\r
-    ends_tolerance.param_set_range(0., 1.);\r
-    parallel_offset.param_set_range(0, NR_HUGE);\r
-    tremble_frequency.param_set_range(0.01, 100.);\r
-    tremble_frequency.param_set_increments(.5, 1.5);\r
-    strokeoverlap_rdm.param_set_range(0, 1.);\r
-\r
-    nbtangents.param_make_integer();\r
-    nbtangents.param_set_range(0, NR_HUGE);\r
-    tgtscale.param_set_range(0, NR_HUGE);\r
-    tgtscale.param_set_increments(.1, .5);\r
-    tgtlength.param_set_range(0, NR_HUGE);\r
-    tgtlength.param_set_increments(1., 5.);\r
-    tgtlength_rdm.param_set_range(0, 1.);\r
-}\r
-\r
-LPESketch::~LPESketch()\r
-{\r
-\r
-}\r
-\r
-/*\r
-Geom::Piecewise<Geom::D2<Geom::SBasis> >\r
-addLinearEnds (Geom::Piecewise<Geom::D2<Geom::SBasis> > & m){\r
-    using namespace Geom;\r
-    Piecewise<D2<SBasis> > output;\r
-    Piecewise<D2<SBasis> > start;\r
-    Piecewise<D2<SBasis> > end;\r
-    double x,y,vx,vy;\r
-\r
-    x  = m.segs.front()[0].at0();\r
-    y  = m.segs.front()[1].at0();\r
-    vx = m.segs.front()[0][1][0]+Tri(m.segs.front()[0][0]);\r
-    vy = m.segs.front()[1][1][0]+Tri(m.segs.front()[1][0]);\r
-    start = Piecewise<D2<SBasis> >(D2<SBasis>(Linear (x-vx,x),Linear (y-vy,y)));\r
-    start.offsetDomain(m.cuts.front()-1.);\r
-\r
-    x  = m.segs.back()[0].at1();\r
-    y  = m.segs.back()[1].at1();\r
-    vx = -m.segs.back()[0][1][1]+Tri(m.segs.back()[0][0]);;\r
-    vy = -m.segs.back()[1][1][1]+Tri(m.segs.back()[1][0]);;\r
-    end = Piecewise<D2<SBasis> >(D2<SBasis>(Linear (x,x+vx),Linear (y,y+vy)));\r
-    //end.offsetDomain(m.cuts.back());\r
-\r
-    output = start;\r
-    output.concat(m);\r
-    output.concat(end);\r
-    return output;\r
-}\r
-*/\r
-\r
-//TODO: does this already exist in 2Geom? if not, move this there...\r
-std::vector<Geom::Piecewise<Geom::D2<Geom::SBasis> > > \r
-split_at_discontinuities (Geom::Piecewise<Geom::D2<Geom::SBasis> > & pwsbin, double tol = .0001)\r
-{\r
-    using namespace Geom;\r
-    std::vector<Piecewise<D2<SBasis> > > ret;\r
-    unsigned piece_start = 0;\r
-    for (unsigned i=0; i<pwsbin.segs.size(); i++){\r
-        if (i==(pwsbin.segs.size()-1) || L2(pwsbin.segs[i].at1()- pwsbin.segs[i+1].at0()) > tol){\r
-            Piecewise<D2<SBasis> > piece;\r
-            piece.cuts.push_back(pwsbin.cuts[piece_start]);\r
-            for (unsigned j = piece_start; j<i+1; j++){\r
-                piece.segs.push_back(pwsbin.segs[j]);\r
-                piece.cuts.push_back(pwsbin.cuts[j+1]);                \r
-            }\r
-            ret.push_back(piece);\r
-            piece_start = i+1;\r
-        }\r
-    }\r
-    return ret;\r
-}\r
-\r
-//This returns a random perturbation. Notice the domain is [s0,s0+first multiple of period>s1]...\r
-Geom::Piecewise<Geom::D2<Geom::SBasis> > \r
-LPESketch::computePerturbation (double s0, double s1){\r
-    using namespace Geom;\r
-    Piecewise<D2<SBasis> >res;\r
-    \r
-    //global offset for this stroke.\r
-    double offsetX = parallel_offset-parallel_offset.get_value();\r
-    double offsetY = parallel_offset-parallel_offset.get_value();\r
-    Point A,dA,B,dB,offset = Point(offsetX,offsetY);\r
-    //start point A\r
-    for (unsigned dim=0; dim<2; dim++){\r
-        A[dim]  = offset[dim] + 2*tremble_size-tremble_size.get_value();\r
-        dA[dim] = 2*tremble_size-tremble_size.get_value();\r
-    }\r
-    //compute howmany deg 3 sbasis to concat according to frequency.\r
-    unsigned count = unsigned((s1-s0)/strokelength*tremble_frequency)+1; \r
-    for (unsigned i=0; i<count; i++){\r
-        D2<SBasis> perturb = D2<SBasis>();\r
-        for (unsigned dim=0; dim<2; dim++){\r
-            B[dim] = offset[dim] + 2*tremble_size-tremble_size.get_value();\r
-            perturb[dim].push_back(Linear(A[dim],B[dim]));\r
-            dA[dim] = dA[dim]-B[dim]+A[dim];\r
-            dB[dim] = 2*tremble_size-tremble_size.get_value();\r
-            perturb[dim].push_back(Linear(dA[dim],dB[dim]));\r
-        }\r
-        A = B;\r
-        dA = B-A-dB;\r
-        res.concat(Piecewise<D2<SBasis> >(perturb));\r
-    }\r
-    res.setDomain(Interval(s0,s0+count*strokelength/tremble_frequency));\r
-    return res;\r
-}\r
-\r
-\r
-// Main effect body...\r
-Geom::Piecewise<Geom::D2<Geom::SBasis> >\r
-LPESketch::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > & pwd2_in)\r
-{\r
-    using namespace Geom;\r
-    Piecewise<D2<SBasis> > output;\r
-\r
-\r
-    //init random parameters.\r
-    parallel_offset.resetRandomizer();\r
-    strokelength_rdm.resetRandomizer();\r
-    strokeoverlap_rdm.resetRandomizer();\r
-    tgtlength_rdm.resetRandomizer();\r
-\r
-    // some variables for futur use.\r
-    // notations will be : t = path time, s = distance from start along the path.\r
-    Piecewise<SBasis> pathlength;\r
-    std::vector<double> times;  \r
-    double total_length;\r
-\r
-    //TODO: split Construction Lines/Approximated Strokes into two separate effects?\r
-\r
-    //----- Approximated Strokes.\r
-    //TODO: choose length & offset according to curvature?\r
-    \r
-    //TODO: retrieve components from path, dont merge to separate afterward! + know if closed!\r
-    std::vector<Piecewise<D2<SBasis> > > pieces_in = split_at_discontinuities (pwd2_in);\r
-\r
-    //work separately on each component.\r
-    for (unsigned pieceidx = 0; pieceidx < pieces_in.size(); pieceidx++){\r
-\r
-        Piecewise<D2<SBasis> > piece = pieces_in[pieceidx];\r
-        Piecewise<SBasis> piecelength = arcLengthSb(piece,.1);\r
-        pathlength.concat(piecelength);\r
-        \r
-        total_length = piecelength.segs.back().at1()-piecelength.segs.front().at0();\r
-\r
-        //TODO: better check this on the Geom::Path.\r
-        bool closed = piece.segs.front().at0() == piece.segs.back().at1(); \r
-        if (closed){ \r
-            piece.concat(piece);\r
-            piecelength.concat(piecelength+total_length);\r
-        }\r
-\r
-        for (unsigned i = 0; i<nbiter_approxstrokes; i++){\r
-            //Basic steps: \r
-            //- Choose a rdm seg [s0,s1], find coresponding [t0,t1], \r
-            //- Pick a rdm perturbation delta(s), collect 'piece(t)+delta(s(t))' over [t0,t1] into output.\r
-\r
-            // pick a point where to start the stroke (s0 = dist from start).\r
-            double s1=0.,s0 = ends_tolerance*strokelength+0.0001;//the root finder might miss 0.  \r
-            double t1, t0;\r
-            double s0_initial = s0;\r
-            bool done = false;// was the end of the component reached?\r
-\r
-            while (!done){\r
-                // if the start point is already too far... do nothing. (this should not happen!)\r
-                assert (s0>=0);//this should not happen!!\r
-                if (!closed && s1>total_length - ends_tolerance.get_value()*strokelength) break;\r
-                if ( closed && s0>total_length + s0_initial) break;\r
-\r
-                times = roots(piecelength-s0);  \r
-                if (times.size()==0) break;//we should not be there.\r
-                t0 = times[0];\r
-                \r
-                // pick a new end point (s1 = s0 + strokelength).\r
-                s1 = s0 + strokelength*(1-strokelength_rdm);\r
-                // don't let it go beyond the end of the orgiginal path.\r
-                // TODO/FIXME: this might result in short strokes near the end...\r
-                if (!closed && s1>total_length-ends_tolerance.get_value()*strokelength){\r
-                    done = true;\r
-                    //!!the root solver might miss s1==total_length...\r
-                    if (s1>total_length){s1 = total_length - ends_tolerance*strokelength-0.0001;}\r
-                }\r
-                if (closed && s1>total_length + s0_initial){\r
-                    done = true;\r
-                    if (closed && s1>2*total_length){s1 = 2*total_length - strokeoverlap*(1-strokeoverlap_rdm)*strokelength-0.0001;}\r
-                }\r
-                times = roots(piecelength-s1);  \r
-                if (times.size()==0) break;//we should not be there.\r
-                t1 = times[0];\r
-                \r
-                //pick a rdm perturbation, and collect the perturbed piece into output.\r
-                Piecewise<D2<SBasis> > pwperturb = computePerturbation(s0,s1);\r
-                pwperturb = compose(pwperturb,portion(piecelength,t0,t1));\r
-                output.concat(portion(piece,t0,t1)+pwperturb);\r
-                \r
-                //step points: s0 = s1 - overlap.\r
-                //TODO: make sure this has to end?\r
-                s0 = s1 - strokeoverlap*(1-strokeoverlap_rdm)*strokelength;\r
-            }\r
-        }\r
-    }\r
-\r
-\r
-    //----- Construction lines.\r
-    //TODO: choose places according to curvature?.\r
-\r
-    //at this point we have:\r
-    //pathlength = arcLengthSb(pwd2_in,.1);\r
-    total_length = pathlength.segs.back().at1();\r
-    Piecewise<D2<SBasis> > m = pwd2_in;\r
-    Piecewise<D2<SBasis> > v = derivative(pwd2_in);\r
-    Piecewise<D2<SBasis> > a = derivative(v);\r
-    for (unsigned i=0; i<nbtangents; i++){\r
-        // pick a point where to draw a tangent (s = dist from start along path).\r
-        double s = total_length * ( i + tgtlength_rdm ) / (nbtangents+1.);\r
-        times = roots(pathlength-s);\r
-        assert(times.size()>0);//there should be one and only one solution!\r
-        double t = times[0];\r
-        Point m_t = m(t), v_t = v(t), a_t = a(t);\r
-        //Compute tgt length according to curvature (not exceeding tgtlength) so that  \r
-        //  dist to origninal curve ~ 4 * (parallel_offset+tremble_size).\r
-        //TODO: put this 4 as a parameter in the UI...\r
-        //TODO: what if with v=0?\r
-        double l = tgtlength*(1-tgtlength_rdm)/v_t.length();\r
-        double r = pow(v_t.length(),3)/cross(a_t,v_t);\r
-        r = sqrt((2*fabs(r)-tgtscale)*tgtscale)/v_t.length();\r
-        l=(r<l)?r:l;\r
-        //collect the tgt segment into output.\r
-        D2<SBasis> tgt = D2<SBasis>();\r
-        for (unsigned dim=0; dim<2; dim++){\r
-            tgt[dim] = SBasis(Linear(m_t[dim]-v_t[dim]*l, m_t[dim]+v_t[dim]*l));\r
-        }\r
-        output.concat(Piecewise<D2<SBasis> >(tgt));\r
-    }\r
-\r
-// // -------- Pleins et delies vs courbure ou direction...\r
-//     Piecewise<D2<SBasis> > a = derivative(v);\r
-//     Piecewise<SBasis> a_cross_n = cross(a,n);\r
-//     Piecewise<SBasis> v_dot_n = dot(v,n);\r
-//     //Piecewise<D2<SBasis> > rfrac = sectionize(D2<Piecewise<SBasis> >(a_cross_n,v_dot_n));\r
-//     //Piecewise<SBasis> h = atan2(rfrac)*para1;\r
-//     Piecewise<SBasis> h = reciprocal(curvature(piece))*para1;\r
-//\r
-// //    Piecewise<D2<SBasis> > dir = Piecewise<D2<SBasis> >(D2<SBasis>(Linear(0),Linear(-1)));\r
-// //    Piecewise<SBasis> h = dot(n,dir)+1.;\r
-// //    h *= h*(para1/4.);\r
-//\r
-//     n = rot90(n);\r
-//     output = piece+h*n;\r
-//     output.concat(piece-h*n);\r
-//\r
-// //-----------\r
-\r
-    //output.concat(m);\r
-    return output;\r
-}\r
-\r
-/* ######################## */\r
-\r
-} //namespace LivePathEffect (setq default-directory "c:/Documents And Settings/jf/Mes Documents/InkscapeSVN")\r
-} /* namespace Inkscape */\r
-\r
-/*\r
-  Local Variables:\r
-  mode:c++\r
-  c-file-style:"stroustrup"\r
-  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))\r
-  indent-tabs-mode:nil\r
-  fill-column:99\r
-  End:\r
-*/\r
-// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :\r
+/** @file
+ * @brief LPE sketch effect implementation
+ */
+/* Authors:
+ *   Jean-Francois Barraud <jf.barraud@gmail.com>
+ *   Johan Engelen <j.b.c.engelen@utwente.nl>
+ *
+ * Copyright (C) 2007 Authors
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include "live_effects/lpe-sketch.h"
+
+// You might need to include other 2geom files. You can add them here:
+#include <2geom/path.h>
+#include <2geom/sbasis.h>
+#include <2geom/sbasis-geometric.h>
+#include <2geom/sbasis-math.h>
+#include <2geom/bezier-to-sbasis.h>
+#include <2geom/sbasis-to-bezier.h>
+#include <2geom/d2.h>
+#include <2geom/sbasis-math.h>
+#include <2geom/piecewise.h>
+#include <2geom/crossing.h>
+#include <2geom/path-intersection.h>
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+LPESketch::LPESketch(LivePathEffectObject *lpeobject) :
+    Effect(lpeobject),
+    // initialise your parameters here:
+    //testpointA(_("Test Point A"), _("Test A"), "ptA", &wr, this, Geom::Point(100,100)),
+    nbiter_approxstrokes(_("Strokes:"), _("Draw that many approximating strokes"), "nbiter_approxstrokes", &wr, this, 5),
+    strokelength(_("Max stroke length:"),
+                 _("Maximum length of approximating strokes"), "strokelength", &wr, this, 100.),
+    strokelength_rdm(_("Stroke length variation:"),
+                     _("Random variation of stroke length (relative to maximum length)"), "strokelength_rdm", &wr, this, .3),
+    strokeoverlap(_("Max. overlap:"),
+                  _("How much successive strokes should overlap (relative to maximum length)"), "strokeoverlap", &wr, this, .3),
+    strokeoverlap_rdm(_("Overlap variation:"),
+                      _("Random variation of overlap (relative to maximum overlap)"), "strokeoverlap_rdm", &wr, this, .3),
+    ends_tolerance(_("Max. end tolerance:"),
+                   _("Maximum distance between ends of original and approximating paths (relative to maximum length)"), "ends_tolerance", &wr, this, .1),
+    parallel_offset(_("Average offset:"),
+                    _("Average distance each stroke is away from the original path"), "parallel_offset", &wr, this, 5.),
+    tremble_size(_("Max. tremble:"),
+                 _("Maximum tremble magnitude"), "tremble_size", &wr, this, 5.),
+    tremble_frequency(_("Tremble frequency:"),
+                      _("Average number of tremble periods in a stroke"), "tremble_frequency", &wr, this, 1.)
+#ifdef LPE_SKETCH_USE_CONSTRUCTION_LINES
+    ,nbtangents(_("Construction lines:"),
+               _("How many construction lines (tangents) to draw"), "nbtangents", &wr, this, 5),
+    tgtscale(_("Scale:"),
+             _("Scale factor relating curvature and length of construction lines (try 5*offset)"), "tgtscale", &wr, this, 10.0),
+    tgtlength(_("Max. length:"), _("Maximum length of construction lines"), "tgtlength", &wr, this, 100.0),
+    tgtlength_rdm(_("Length variation:"), _("Random variation of the length of construction lines"), "tgtlength_rdm", &wr, this, .3),
+    tgt_places_rdmness(_("Placement randomness:"), _("0: evenly distributed construction lines, 1: purely random placement"), "tgt_places_rdmness", &wr, this, 1.)
+#ifdef LPE_SKETCH_USE_CURVATURE
+    ,min_curvature(_("k_min:"), _("min curvature"), "k_min", &wr, this, 4.0)
+    ,max_curvature(_("k_max:"), _("max curvature"), "k_max", &wr, this, 1000.0)
+#endif
+#endif
+{
+    // register all your parameters here, so Inkscape knows which parameters this effect has:
+    //Add some comment in the UI:  *warning* the precise output of this effect might change in future releases!
+    //convert to path if you want to keep exact output unchanged in future releases...
+    //registerParameter( dynamic_cast<Parameter *>(&testpointA) );
+    registerParameter( dynamic_cast<Parameter *>(&nbiter_approxstrokes) );
+    registerParameter( dynamic_cast<Parameter *>(&strokelength) );
+    registerParameter( dynamic_cast<Parameter *>(&strokelength_rdm) );
+    registerParameter( dynamic_cast<Parameter *>(&strokeoverlap) );
+    registerParameter( dynamic_cast<Parameter *>(&strokeoverlap_rdm) );
+    registerParameter( dynamic_cast<Parameter *>(&ends_tolerance) );
+    registerParameter( dynamic_cast<Parameter *>(&parallel_offset) );
+    registerParameter( dynamic_cast<Parameter *>(&tremble_size) );
+    registerParameter( dynamic_cast<Parameter *>(&tremble_frequency) );
+#ifdef LPE_SKETCH_USE_CONSTRUCTION_LINES
+    registerParameter( dynamic_cast<Parameter *>(&nbtangents) );
+    registerParameter( dynamic_cast<Parameter *>(&tgt_places_rdmness) );
+    registerParameter( dynamic_cast<Parameter *>(&tgtscale) );
+    registerParameter( dynamic_cast<Parameter *>(&tgtlength) );
+    registerParameter( dynamic_cast<Parameter *>(&tgtlength_rdm) );
+#ifdef LPE_SKETCH_USE_CURVATURE
+    registerParameter( dynamic_cast<Parameter *>(&min_curvature) );
+    registerParameter( dynamic_cast<Parameter *>(&max_curvature) );
+#endif
+#endif
+
+    nbiter_approxstrokes.param_make_integer();
+    nbiter_approxstrokes.param_set_range(0, NR_HUGE);
+    strokelength.param_set_range(1, NR_HUGE);
+    strokelength.param_set_increments(1., 5.);
+    strokelength_rdm.param_set_range(0, 1.);
+    strokeoverlap.param_set_range(0, 1.);
+    strokeoverlap.param_set_increments(0.1, 0.30);
+    ends_tolerance.param_set_range(0., 1.);
+    parallel_offset.param_set_range(0, NR_HUGE);
+    tremble_frequency.param_set_range(0.01, 100.);
+    tremble_frequency.param_set_increments(.5, 1.5);
+    strokeoverlap_rdm.param_set_range(0, 1.);
+
+#ifdef LPE_SKETCH_USE_CONSTRUCTION_LINES
+    nbtangents.param_make_integer();
+    nbtangents.param_set_range(0, NR_HUGE);
+    tgtscale.param_set_range(0, NR_HUGE);
+    tgtscale.param_set_increments(.1, .5);
+    tgtlength.param_set_range(0, NR_HUGE);
+    tgtlength.param_set_increments(1., 5.);
+    tgtlength_rdm.param_set_range(0, 1.);
+    tgt_places_rdmness.param_set_range(0, 1.);
+    //this is not very smart, but required to avoid having lot of tangents stacked on short components.
+    //Nota: we could specify a density instead of an absolute number, but this would be scale dependant.
+    concatenate_before_pwd2 = true;
+#endif
+}
+
+LPESketch::~LPESketch()
+{
+
+}
+
+/*
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+addLinearEnds (Geom::Piecewise<Geom::D2<Geom::SBasis> > & m){
+    using namespace Geom;
+    Piecewise<D2<SBasis> > output;
+    Piecewise<D2<SBasis> > start;
+    Piecewise<D2<SBasis> > end;
+    double x,y,vx,vy;
+
+    x  = m.segs.front()[0].at0();
+    y  = m.segs.front()[1].at0();
+    vx = m.segs.front()[0][1][0]+Tri(m.segs.front()[0][0]);
+    vy = m.segs.front()[1][1][0]+Tri(m.segs.front()[1][0]);
+    start = Piecewise<D2<SBasis> >(D2<SBasis>(Linear (x-vx,x),Linear (y-vy,y)));
+    start.offsetDomain(m.cuts.front()-1.);
+
+    x  = m.segs.back()[0].at1();
+    y  = m.segs.back()[1].at1();
+    vx = -m.segs.back()[0][1][1]+Tri(m.segs.back()[0][0]);;
+    vy = -m.segs.back()[1][1][1]+Tri(m.segs.back()[1][0]);;
+    end = Piecewise<D2<SBasis> >(D2<SBasis>(Linear (x,x+vx),Linear (y,y+vy)));
+    //end.offsetDomain(m.cuts.back());
+
+    output = start;
+    output.concat(m);
+    output.concat(end);
+    return output;
+}
+*/
+
+
+
+//This returns a random perturbation. Notice the domain is [s0,s0+first multiple of period>s1]...
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+LPESketch::computePerturbation (double s0, double s1){
+    using namespace Geom;
+    Piecewise<D2<SBasis> >res;
+
+    //global offset for this stroke.
+    double offsetX = 2*parallel_offset-parallel_offset.get_value();
+    double offsetY = 2*parallel_offset-parallel_offset.get_value();
+    Point A,dA,B,dB,offset = Point(offsetX,offsetY);
+    //start point A
+    for (unsigned dim=0; dim<2; dim++){
+        A[dim]  = offset[dim] + 2*tremble_size-tremble_size.get_value();
+        dA[dim] = 2*tremble_size-tremble_size.get_value();
+    }
+    //compute howmany deg 3 sbasis to concat according to frequency.
+
+    unsigned count = unsigned((s1-s0)/strokelength*tremble_frequency)+1; 
+    //unsigned count = unsigned((s1-s0)/tremble_frequency)+1; 
+
+    for (unsigned i=0; i<count; i++){
+        D2<SBasis> perturb = D2<SBasis>(SBasis(2, Linear()), SBasis(2, Linear()));
+        for (unsigned dim=0; dim<2; dim++){
+            B[dim] = offset[dim] + 2*tremble_size-tremble_size.get_value();
+            perturb[dim][0] = Linear(A[dim],B[dim]);
+            dA[dim] = dA[dim]-B[dim]+A[dim];
+            //avoid dividing by 0. Very short strokes will have ends parallel to the curve...
+            if ( s1-s0 > 1e-2)
+                dB[dim] = -(2*tremble_size-tremble_size.get_value())/(s0-s1)-B[dim]+A[dim];
+            else
+                dB[dim] = -(2*tremble_size-tremble_size.get_value())-B[dim]+A[dim];
+            perturb[dim][1] = Linear(dA[dim],dB[dim]);
+        }
+        dA = B-A-dB;
+        A = B;
+        //dA = B-A-dB;
+        res.concat(Piecewise<D2<SBasis> >(perturb));
+    }
+    res.setDomain(Interval(s0,s0+count*strokelength/tremble_frequency));
+    //res.setDomain(Interval(s0,s0+count*tremble_frequency));
+    return res;
+}
+
+
+// Main effect body...
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+LPESketch::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
+{
+    using namespace Geom;
+    //If the input path is empty, do nothing.
+    //Note: this happens when duplicating a 3d box... dunno why.
+    if (pwd2_in.size()==0) return pwd2_in;
+
+    Piecewise<D2<SBasis> > output;
+
+    // some variables for futur use (for construction lines; compute arclength only once...)
+    // notations will be : t = path time, s = distance from start along the path.
+    Piecewise<SBasis> pathlength;
+    double total_length = 0;
+
+    //TODO: split Construction Lines/Approximated Strokes into two separate effects?
+
+    //----- Approximated Strokes.
+    std::vector<Piecewise<D2<SBasis> > > pieces_in = split_at_discontinuities (pwd2_in);
+
+    //work separately on each component.
+    for (unsigned pieceidx = 0; pieceidx < pieces_in.size(); pieceidx++){
+
+        Piecewise<D2<SBasis> > piece = pieces_in[pieceidx];
+        Piecewise<SBasis> piecelength = arcLengthSb(piece,.1);
+        double piece_total_length = piecelength.segs.back().at1()-piecelength.segs.front().at0();
+        pathlength.concat(piecelength + total_length);
+        total_length += piece_total_length;
+
+
+        //TODO: better check this on the Geom::Path.
+        bool closed = piece.segs.front().at0() == piece.segs.back().at1();
+        if (closed){
+            piece.concat(piece);
+            piecelength.concat(piecelength+piece_total_length);
+        }
+
+        for (unsigned i = 0; i<nbiter_approxstrokes; i++){
+            //Basic steps:
+            //- Choose a rdm seg [s0,s1], find coresponding [t0,t1],
+            //- Pick a rdm perturbation delta(s), collect 'piece(t)+delta(s(t))' over [t0,t1] into output.
+
+            // pick a point where to start the stroke (s0 = dist from start).
+            double s1=0.,s0 = ends_tolerance*strokelength+0.0001;//the root finder might miss 0.
+            double t1, t0;
+            double s0_initial = s0;
+            bool done = false;// was the end of the component reached?
+
+            while (!done){
+                // if the start point is already too far... do nothing. (this should not happen!)
+                if (!closed && s1>piece_total_length - ends_tolerance.get_value()*strokelength) break;
+                if ( closed && s0>piece_total_length + s0_initial) break;
+
+                std::vector<double> times;
+                times = roots(piecelength-s0);
+                t0 = times.at(0);//there should be one and only one solution!!
+
+                // pick a new end point (s1 = s0 + strokelength).
+                s1 = s0 + strokelength*(1-strokelength_rdm);
+                // don't let it go beyond the end of the orgiginal path.
+                // TODO/FIXME: this might result in short strokes near the end...
+                if (!closed && s1>piece_total_length-ends_tolerance.get_value()*strokelength){
+                    done = true;
+                    //!!the root solver might miss s1==piece_total_length...
+                    if (s1>piece_total_length){s1 = piece_total_length - ends_tolerance*strokelength-0.0001;}
+                }
+                if (closed && s1>piece_total_length + s0_initial){
+                    done = true;
+                    if (closed && s1>2*piece_total_length){
+                        s1 = 2*piece_total_length - strokeoverlap*(1-strokeoverlap_rdm)*strokelength-0.0001;
+                    }
+                }
+                times = roots(piecelength-s1);
+                if (times.size()==0) break;//we should not be there.
+                t1 = times[0];
+
+                //pick a rdm perturbation, and collect the perturbed piece into output.
+                Piecewise<D2<SBasis> > pwperturb = computePerturbation(s0-0.01,s1+0.01);
+                pwperturb = compose(pwperturb,portion(piecelength,t0,t1));
+
+                output.concat(portion(piece,t0,t1)+pwperturb);
+
+                //step points: s0 = s1 - overlap.
+                //TODO: make sure this has to end?
+                s0 = s1 - strokeoverlap*(1-strokeoverlap_rdm)*(s1-s0);
+            }
+        }
+    }
+
+#ifdef LPE_SKETCH_USE_CONSTRUCTION_LINES
+
+    //----- Construction lines.
+    //TODO: choose places according to curvature?.
+
+    //at this point we should have:
+    //pathlength = arcLengthSb(pwd2_in,.1);
+    //total_length = pathlength.segs.back().at1()-pathlength.segs.front().at0();
+    Piecewise<D2<SBasis> > m = pwd2_in;
+    Piecewise<D2<SBasis> > v = derivative(pwd2_in);
+    Piecewise<D2<SBasis> > a = derivative(v);
+
+#ifdef LPE_SKETCH_USE_CURVATURE
+    //---- curvature experiment...(enable
+    Piecewise<SBasis> k = curvature(pwd2_in);
+    OptInterval k_bnds = bounds_exact(abs(k));
+    double k_min = k_bnds->min() + k_bnds->extent() * min_curvature;
+    double k_max = k_bnds->min() + k_bnds->extent() * max_curvature;
+
+    Piecewise<SBasis> bump;
+    //SBasis bump_seg = SBasis( 2, Linear(0) );
+    //bump_seg[1] = Linear( 4. );
+    SBasis bump_seg = SBasis( 1, Linear(1) );
+    bump.push_cut( k_bnds->min() - 1 );
+    bump.push( Linear(0), k_min );
+    bump.push(bump_seg,k_max);
+    bump.push( Linear(0), k_bnds->max()+1 );
+        
+    Piecewise<SBasis> repartition = compose( bump, k );
+    repartition = integral(repartition);
+    //-------------------------------
+#endif
+
+    for (unsigned i=0; i<nbtangents; i++){
+
+        // pick a point where to draw a tangent (s = dist from start along path).
+#ifdef LPE_SKETCH_USE_CURVATURE
+        double proba = repartition.firstValue()+ (rand()%100)/100.*(repartition.lastValue()-repartition.firstValue());
+        std::vector<double> times;
+        times = roots(repartition - proba);
+        double t = times.at(0);//there should be one and only one solution!
+#else
+        //double s = total_length * ( i + tgtlength_rdm ) / (nbtangents+1.);
+        double reg_place = total_length * ( i + .5) / ( nbtangents );
+        double rdm_place = total_length * tgt_places_rdmness;
+        double s = ( 1.- tgt_places_rdmness.get_value() ) * reg_place  +  rdm_place ;
+        std::vector<double> times;
+        times = roots(pathlength-s);
+        double t = times.at(0);//there should be one and only one solution!
+#endif
+        Point m_t = m(t), v_t = v(t), a_t = a(t);
+        //Compute tgt length according to curvature (not exceeding tgtlength) so that
+        //  dist to origninal curve ~ 4 * (parallel_offset+tremble_size).
+        //TODO: put this 4 as a parameter in the UI...
+        //TODO: what if with v=0?
+        double l = tgtlength*(1-tgtlength_rdm)/v_t.length();
+        double r = pow(v_t.length(),3)/cross(a_t,v_t);
+        r = sqrt((2*fabs(r)-tgtscale)*tgtscale)/v_t.length();
+        l=(r<l)?r:l;
+        //collect the tgt segment into output.
+        D2<SBasis> tgt = D2<SBasis>();
+        for (unsigned dim=0; dim<2; dim++){
+            tgt[dim] = SBasis(Linear(m_t[dim]-v_t[dim]*l, m_t[dim]+v_t[dim]*l));
+        }
+        output.concat(Piecewise<D2<SBasis> >(tgt));
+    }
+#endif
+
+    return output;
+}
+
+void
+LPESketch::doBeforeEffect (SPLPEItem */*lpeitem*/)
+{
+    //init random parameters.
+    parallel_offset.resetRandomizer();
+    strokelength_rdm.resetRandomizer();
+    strokeoverlap_rdm.resetRandomizer();
+    ends_tolerance.resetRandomizer();
+    tremble_size.resetRandomizer();
+#ifdef LPE_SKETCH_USE_CONSTRUCTION_LINES
+    tgtlength_rdm.resetRandomizer();
+    tgt_places_rdmness.resetRandomizer();
+#endif
+}
+
+/* ######################## */
+
+} //namespace LivePathEffect (setq default-directory "c:/Documents And Settings/jf/Mes Documents/InkscapeSVN")
+} /* namespace Inkscape */
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :