e72f1aac15026d7b57f63ca547c997f329b7849a
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"
22 #include "xml/repr.h"
24 #include <2geom/path.h>
25 #include <2geom/piecewise.h>
26 #include <2geom/sbasis.h>
27 #include <2geom/sbasis-geometric.h>
28 #include <2geom/bezier-to-sbasis.h>
29 #include <2geom/sbasis-to-bezier.h>
30 #include <2geom/d2.h>
31 #include <2geom/matrix.h>
34 #include "ui/widget/scalar.h"
35 #include "libnr/nr-values.h"
37 namespace Inkscape {
38 namespace LivePathEffect {
40 using namespace Geom;
42 LPECurveStitch::LPECurveStitch(LivePathEffectObject *lpeobject) :
43 Effect(lpeobject),
44 strokepath(_("Stroke path"), _("The path that will be used as stitch."), "strokepath", &wr, this, "M0,0 L1,0"),
45 nrofpaths(_("Number of paths"), _("The number of paths that will be generated."), "count", &wr, this, 5),
46 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),
47 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),
48 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),
49 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),
50 prop_scale(_("Scale width"), _("Scaling of the width of the stroke path"), "prop_scale", &wr, this, 1),
51 scale_y_rel(_("Scale width relative"), _("Scale the width of the stroke path relative to its length"), "scale_y_rel", &wr, this, false)
52 {
53 registerParameter( dynamic_cast<Parameter *>(&nrofpaths) );
54 registerParameter( dynamic_cast<Parameter *>(&startpoint_edge_variation) );
55 registerParameter( dynamic_cast<Parameter *>(&startpoint_spacing_variation) );
56 registerParameter( dynamic_cast<Parameter *>(&endpoint_edge_variation) );
57 registerParameter( dynamic_cast<Parameter *>(&endpoint_spacing_variation) );
58 registerParameter( dynamic_cast<Parameter *>(&strokepath) );
59 registerParameter( dynamic_cast<Parameter *>(&prop_scale) );
60 registerParameter( dynamic_cast<Parameter *>(&scale_y_rel) );
62 nrofpaths.param_make_integer();
63 nrofpaths.param_set_range(2, NR_HUGE);
65 prop_scale.param_set_digits(3);
66 prop_scale.param_set_increments(0.01, 0.10);
67 }
69 LPECurveStitch::~LPECurveStitch()
70 {
72 }
74 std::vector<Geom::Path>
75 LPECurveStitch::doEffect_path (std::vector<Geom::Path> & path_in)
76 {
77 if (path_in.size() >= 2) {
78 startpoint_edge_variation.resetRandomizer();
79 endpoint_edge_variation.resetRandomizer();
80 startpoint_spacing_variation.resetRandomizer();
81 endpoint_spacing_variation.resetRandomizer();
83 D2<Piecewise<SBasis> > stroke = make_cuts_independant(strokepath);
84 Interval bndsStroke = bounds_exact(stroke[0]);
85 gdouble scaling = bndsStroke.max() - bndsStroke.min();
86 Interval bndsStrokeY = bounds_exact(stroke[1]);
87 Point stroke_origin(bndsStroke.min(), (bndsStrokeY.max()+bndsStrokeY.min())/2);
89 std::vector<Geom::Path> path_out;
91 // do this for all permutations (ii,jj) if there are more than 2 paths? realllly cool!
92 for (int ii = 0 ; ii < path_in.size() - 1; ii++)
93 for (int jj = ii+1; jj < path_in.size(); jj++)
94 {
95 Piecewise<D2<SBasis> > A = arc_length_parametrization(Piecewise<D2<SBasis> >(path_in[ii].toPwSb()),2,.1);
96 Piecewise<D2<SBasis> > B = arc_length_parametrization(Piecewise<D2<SBasis> >(path_in[jj].toPwSb()),2,.1);
97 Interval bndsA = A.domain();
98 Interval bndsB = B.domain();
99 gdouble incrementA = (bndsA.max()-bndsA.min()) / (nrofpaths-1);
100 gdouble incrementB = (bndsB.max()-bndsB.min()) / (nrofpaths-1);
101 gdouble tA = bndsA.min();
102 gdouble tB = bndsB.min();
103 gdouble tAclean = tA; // the tA without spacing_variation
104 gdouble tBclean = tB; // the tB without spacing_variation
106 for (int i = 0; i < nrofpaths; i++) {
107 Point start = A(tA);
108 Point end = B(tB);
109 if (startpoint_edge_variation.get_value() != 0)
110 start = start + (startpoint_edge_variation - startpoint_edge_variation.get_value()/2) * (end - start);
111 if (endpoint_edge_variation.get_value() != 0)
112 end = end + (endpoint_edge_variation - endpoint_edge_variation.get_value()/2)* (end - start);
114 if (!Geom::are_near(start,end)) {
115 gdouble scaling_y = 1.0;
116 if (scale_y_rel.get_value()) {
117 scaling_y = (L2(end-start)/scaling)*prop_scale;
118 } else {
119 scaling_y = prop_scale;
120 }
122 Matrix transform;
123 transform.setXAxis( (end-start) / scaling );
124 transform.setYAxis( rot90(unit_vector(end-start)) * scaling_y);
125 transform.setTranslation( start );
126 Piecewise<D2<SBasis> > pwd2_out = (strokepath-stroke_origin) * transform;
128 // add stuff to one big pw<d2<sbasis> > and then outside the loop convert to path?
129 // No: this way, the separate result paths are kept separate which might come in handy some time!
130 std::vector<Geom::Path> result = Geom::path_from_piecewise(pwd2_out, LPE_CONVERSION_TOLERANCE);
131 path_out.push_back(result[0]);
132 }
133 gdouble svA = startpoint_spacing_variation - startpoint_spacing_variation.get_value()/2;
134 gdouble svB = endpoint_spacing_variation - endpoint_spacing_variation.get_value()/2;
135 tAclean += incrementA;
136 tBclean += incrementB;
137 tA = tAclean + incrementA * svA;
138 tB = tBclean + incrementB * svB;
139 if (tA > bndsA.max())
140 tA = bndsA.max();
141 if (tB > bndsB.max())
142 tB = bndsB.max();
143 }
144 }
146 return path_out;
147 } else {
148 return path_in;
149 }
150 }
152 void
153 LPECurveStitch::resetDefaults(SPItem * item)
154 {
155 if (!SP_IS_PATH(item)) return;
157 using namespace Geom;
159 // set the stroke path to run horizontally in the middle of the bounding box of the original path
160 Piecewise<D2<SBasis> > pwd2;
161 std::vector<Geom::Path> temppath = SVGD_to_2GeomPath( SP_OBJECT_REPR(item)->attribute("inkscape:original-d"));
162 for (unsigned int i=0; i < temppath.size(); i++) {
163 pwd2.concat( temppath[i].toPwSb() );
164 }
166 D2<Piecewise<SBasis> > d2pw = make_cuts_independant(pwd2);
167 Interval bndsX = bounds_exact(d2pw[0]);
168 Interval bndsY = bounds_exact(d2pw[1]);
169 Point start(bndsX.min(), (bndsY.max()+bndsY.min())/2);
170 Point end(bndsX.max(), (bndsY.max()+bndsY.min())/2);
172 if ( !Geom::are_near(start,end) ) {
173 Geom::Path path;
174 path.start( start );
175 path.appendNew<Geom::LineSegment>( end );
176 strokepath.param_set_and_write_new_value( path.toPwSb() );
177 } else {
178 // bounding box is too small to make decent path. set to default default. :-)
179 strokepath.param_set_and_write_default();
180 }
181 }
183 void
184 LPECurveStitch::transform_multiply(Geom::Matrix const& postmul, bool set)
185 {
186 // only take translations into account
187 if (postmul.isTranslation()) {
188 strokepath.param_transform_multiply(postmul, set);
189 } else if (!scale_y_rel.get_value()) {
190 // this basically means that for this transformation, the result should be the same as normal scaling the result path
191 // don't know how to do this yet.
192 // Geom::Matrix new_postmul;
193 //new_postmul.setIdentity();
194 // new_postmul.setTranslation(postmul.translation());
195 // Effect::transform_multiply(new_postmul, set);
196 }
197 }
199 } //namespace LivePathEffect
200 } /* namespace Inkscape */
202 /*
203 Local Variables:
204 mode:c++
205 c-file-style:"stroustrup"
206 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
207 indent-tabs-mode:nil
208 fill-column:99
209 End:
210 */
211 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :