8dbd9feb153335edcc6e8651c1da8e334b8da671
1 #define INKSCAPE_LPE_CURVESTITCH_CPP
2 /** \file
3 * LPE Curve Stitching implementation, used as an example for a base starting class
4 * when implementing new LivePathEffects.
5 *
6 */
7 /*
8 * Authors:
9 * Johan Engelen
10 *
11 * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
12 *
13 * Released under GNU GPL, read the file 'COPYING' for more information
14 */
16 #include "live_effects/lpe-curvestitch.h"
17 #include "display/curve.h"
18 #include <libnr/n-art-bpath.h>
19 #include "sp-item.h"
20 #include "sp-path.h"
21 #include "live_effects/n-art-bpath-2geom.h"
23 #include <2geom/path.h>
24 #include <2geom/piecewise.h>
25 #include <2geom/sbasis.h>
26 #include <2geom/sbasis-geometric.h>
27 #include <2geom/bezier-to-sbasis.h>
28 #include <2geom/sbasis-to-bezier.h>
29 #include <2geom/d2.h>
30 #include <2geom/matrix.h>
33 #include "ui/widget/scalar.h"
34 #include "libnr/nr-values.h"
36 namespace Inkscape {
37 namespace LivePathEffect {
39 using namespace Geom;
41 LPECurveStitch::LPECurveStitch(LivePathEffectObject *lpeobject) :
42 Effect(lpeobject),
43 strokepath(_("Stroke path"), _("The path that will be used as stitch."), "strokepath", &wr, this, "M0,0 L1,0"),
44 nrofpaths(_("Number of paths"), _("The number of paths that will be generated."), "count", &wr, this, 5),
45 startpoint_edge_variation(_("Start edge variance"), _("The amount of random jitter to move the start points of the stitches inside & outside the guide path"), "startpoint_edge_variation", &wr, this, 0),
46 startpoint_spacing_variation(_("Start spacing variance"), _("The amount of random shifting to move the start points of the stitches back & forth along the guide path"), "startpoint_spacing_variation", &wr, this, 0),
47 endpoint_edge_variation(_("End edge variance"), _("The amount of randomness that moves the end points of the stitches inside & outside the guide path"), "endpoint_edge_variation", &wr, this, 0),
48 endpoint_spacing_variation(_("End spacing variance"), _("The amount of random shifting to move the end points of the stitches back & forth along the guide path"), "endpoint_spacing_variation", &wr, this, 0),
49 prop_scale(_("Scale width"), _("Scaling of the width of the stroke path"), "prop_scale", &wr, this, 1),
50 scale_y_rel(_("Scale width relative"), _("Scale the width of the stroke path relative to its length"), "scale_y_rel", &wr, this, false)
51 {
52 registerParameter( dynamic_cast<Parameter *>(&nrofpaths) );
53 registerParameter( dynamic_cast<Parameter *>(&startpoint_edge_variation) );
54 registerParameter( dynamic_cast<Parameter *>(&startpoint_spacing_variation) );
55 registerParameter( dynamic_cast<Parameter *>(&endpoint_edge_variation) );
56 registerParameter( dynamic_cast<Parameter *>(&endpoint_spacing_variation) );
57 registerParameter( dynamic_cast<Parameter *>(&strokepath) );
58 registerParameter( dynamic_cast<Parameter *>(&prop_scale) );
59 registerParameter( dynamic_cast<Parameter *>(&scale_y_rel) );
61 nrofpaths.param_make_integer();
62 nrofpaths.param_set_range(2, NR_HUGE);
64 prop_scale.param_set_digits(3);
65 prop_scale.param_set_increments(0.01, 0.10);
66 }
68 LPECurveStitch::~LPECurveStitch()
69 {
71 }
73 std::vector<Geom::Path>
74 LPECurveStitch::doEffect_path (std::vector<Geom::Path> & path_in)
75 {
76 if (path_in.size() >= 2) {
77 startpoint_edge_variation.resetRandomizer();
78 endpoint_edge_variation.resetRandomizer();
79 startpoint_spacing_variation.resetRandomizer();
80 endpoint_spacing_variation.resetRandomizer();
82 D2<Piecewise<SBasis> > stroke = make_cuts_independant(strokepath);
83 Interval bndsStroke = bounds_exact(stroke[0]);
84 gdouble scaling = bndsStroke.max() - bndsStroke.min();
85 Interval bndsStrokeY = bounds_exact(stroke[1]);
86 Point stroke_origin(bndsStroke.min(), (bndsStrokeY.max()+bndsStrokeY.min())/2);
88 std::vector<Geom::Path> path_out;
90 // do this for all permutations (ii,jj) if there are more than 2 paths? realllly cool!
91 for (int ii = 0 ; ii < path_in.size() - 1; ii++)
92 for (int jj = ii+1; jj < path_in.size(); jj++)
93 {
94 Piecewise<D2<SBasis> > A = arc_length_parametrization(Piecewise<D2<SBasis> >(path_in[ii].toPwSb()),2,.1);
95 Piecewise<D2<SBasis> > B = arc_length_parametrization(Piecewise<D2<SBasis> >(path_in[jj].toPwSb()),2,.1);
96 Interval bndsA = A.domain();
97 Interval bndsB = B.domain();
98 gdouble incrementA = (bndsA.max()-bndsA.min()) / (nrofpaths-1);
99 gdouble incrementB = (bndsB.max()-bndsB.min()) / (nrofpaths-1);
100 gdouble tA = bndsA.min();
101 gdouble tB = bndsB.min();
102 gdouble tAclean = tA; // the tA without spacing_variation
103 gdouble tBclean = tB; // the tB without spacing_variation
105 for (int i = 0; i < nrofpaths; i++) {
106 Point start = A(tA);
107 Point end = B(tB);
108 if (startpoint_edge_variation.get_value() != 0)
109 start = start + (startpoint_edge_variation - startpoint_edge_variation.get_value()/2) * (end - start);
110 if (endpoint_edge_variation.get_value() != 0)
111 end = end + (endpoint_edge_variation - endpoint_edge_variation.get_value()/2)* (end - start);
113 if (!Geom::are_near(start,end)) {
114 gdouble scaling_y = 1.0;
115 if (scale_y_rel.get_value()) {
116 scaling_y = (L2(end-start)/scaling)*prop_scale;
117 } else {
118 scaling_y = prop_scale;
119 }
121 Matrix transform;
122 transform.setXAxis( (end-start) / scaling );
123 transform.setYAxis( rot90(unit_vector(end-start)) * scaling_y);
124 transform.setTranslation( start );
125 Piecewise<D2<SBasis> > pwd2_out = (strokepath-stroke_origin) * transform;
127 // add stuff to one big pw<d2<sbasis> > and then outside the loop convert to path?
128 // No: this way, the separate result paths are kept separate which might come in handy some time!
129 std::vector<Geom::Path> result = Geom::path_from_piecewise(pwd2_out, LPE_CONVERSION_TOLERANCE);
130 path_out.push_back(result[0]);
131 }
132 gdouble svA = startpoint_spacing_variation - startpoint_spacing_variation.get_value()/2;
133 gdouble svB = endpoint_spacing_variation - endpoint_spacing_variation.get_value()/2;
134 tAclean += incrementA;
135 tBclean += incrementB;
136 tA = tAclean + incrementA * svA;
137 tB = tBclean + incrementB * svB;
138 if (tA > bndsA.max())
139 tA = bndsA.max();
140 if (tB > bndsB.max())
141 tB = bndsB.max();
142 }
143 }
145 return path_out;
146 } else {
147 return path_in;
148 }
149 }
151 void
152 LPECurveStitch::resetDefaults(SPItem * item)
153 {
154 if (!SP_IS_PATH(item)) return;
156 using namespace Geom;
158 // set the stroke path to run horizontally in the middle of the bounding box of the original path
159 Piecewise<D2<SBasis> > pwd2;
160 std::vector<Geom::Path> temppath = SVGD_to_2GeomPath( SP_OBJECT_REPR(item)->attribute("inkscape:original-d"));
161 for (unsigned int i=0; i < temppath.size(); i++) {
162 pwd2.concat( temppath[i].toPwSb() );
163 }
165 D2<Piecewise<SBasis> > d2pw = make_cuts_independant(pwd2);
166 Interval bndsX = bounds_exact(d2pw[0]);
167 Interval bndsY = bounds_exact(d2pw[1]);
168 Point start(bndsX.min(), (bndsY.max()+bndsY.min())/2);
169 Point end(bndsX.max(), (bndsY.max()+bndsY.min())/2);
171 if ( !Geom::are_near(start,end) ) {
172 Geom::Path path;
173 path.start( start );
174 path.appendNew<Geom::LineSegment>( end );
175 strokepath.param_set_and_write_new_value( path.toPwSb() );
176 } else {
177 // bounding box is too small to make decent path. set to default default. :-)
178 strokepath.param_set_and_write_default();
179 }
180 }
182 void
183 LPECurveStitch::transform_multiply(Geom::Matrix const& postmul, bool set)
184 {
185 // only take translations into account
186 if (postmul.isTranslation()) {
187 strokepath.param_transform_multiply(postmul, set);
188 } else if (!scale_y_rel.get_value()) {
189 // this basically means that for this transformation, the result should be the same as normal scaling the result path
190 // don't know how to do this yet.
191 // Geom::Matrix new_postmul;
192 //new_postmul.setIdentity();
193 // new_postmul.setTranslation(postmul.translation());
194 // Effect::transform_multiply(new_postmul, set);
195 }
196 }
198 } //namespace LivePathEffect
199 } /* namespace Inkscape */
201 /*
202 Local Variables:
203 mode:c++
204 c-file-style:"stroustrup"
205 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
206 indent-tabs-mode:nil
207 fill-column:99
208 End:
209 */
210 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :