1 #define INKSCAPE_LPE_PERSPECTIVE_PATH_CPP
2 /** \file
3 * LPE <perspective_path> implementation, used as an example for a base starting class
4 * when implementing new LivePathEffects.
5 *
6 * In vi, three global search-and-replaces will let you rename everything
7 * in this and the .h file:
8 *
9 * :%s/PERSPECTIVE_PATH/YOURNAME/g
10 * :%s/PerspectivePath/Yourname/g
11 * :%s/perspective_path/yourname/g
12 */
13 /*
14 * Authors:
15 * Johan Engelen
16 * Maximilian Albert
17 *
18 * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
19 * Copyright (C) Maximilian Albert 2008 <maximilian.albert@gmail.com>
20 *
21 * Released under GNU GPL, read the file 'COPYING' for more information
22 */
24 #include "persp3d.h"
25 //#include "transf_mat_3x4.h"
26 #include "document.h"
28 #include "live_effects/lpe-perspective_path.h"
29 #include "sp-item-group.h"
31 #include "inkscape.h"
33 // You might need to include other 2geom files. You can add them here:
34 #include <2geom/path.h>
36 namespace Inkscape {
37 namespace LivePathEffect {
39 LPEPerspectivePath::LPEPerspectivePath(LivePathEffectObject *lpeobject) :
40 Effect(lpeobject),
41 // initialise your parameters here:
42 scalex(_("Scale x"), _("Scale factor in x direction"), "scalex", &wr, this, 1.0),
43 scaley(_("Scale y"), _("Scale factor in y direction"), "scaley", &wr, this, 1.0),
44 offsetx(_("Offset x"), _("Offset in x direction"), "offsetx", &wr, this, 0.0),
45 offsety(_("Offset y"), _("Offset in y direction"), "offsety", &wr, this, 0.0),
46 uses_plane_xy(_("Uses XY plane?"), _("If true, put the path on the left side of an imaginary box, otherwise on the right side"), "uses_plane_xy", &wr, this, true)
47 {
48 // register all your parameters here, so Inkscape knows which parameters this effect has:
49 registerParameter( dynamic_cast<Parameter *>(&scalex) );
50 registerParameter( dynamic_cast<Parameter *>(&scaley) );
51 registerParameter( dynamic_cast<Parameter *>(&offsetx) );
52 registerParameter( dynamic_cast<Parameter *>(&offsety) );
53 registerParameter( dynamic_cast<Parameter *>(&uses_plane_xy) );
55 concatenate_before_pwd2 = true; // don't split the path into its subpaths
57 Persp3D *persp = persp3d_document_first_persp(inkscape_active_document());
59 Proj::TransfMat3x4 pmat = persp->tmat;
61 pmat.copy_tmat(tmat);
62 }
64 LPEPerspectivePath::~LPEPerspectivePath()
65 {
67 }
69 void
70 LPEPerspectivePath::doBeforeEffect (SPLPEItem *lpeitem)
71 {
72 original_bbox(lpeitem, true);
73 }
75 Geom::Piecewise<Geom::D2<Geom::SBasis> >
76 LPEPerspectivePath::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
77 {
78 using namespace Geom;
80 Piecewise<D2<SBasis> > path_a_pw = pwd2_in;
82 // FIXME: the minus sign is there because the SVG coordinate system goes down;
83 // remove this once we have unified coordinate systems
84 path_a_pw = path_a_pw + Geom::Point(offsetx, -offsety);
86 D2<Piecewise<SBasis> > B = make_cuts_independant(path_a_pw);
87 Piecewise<SBasis> preimage[4];
89 Geom::Point orig = Geom::Point(uses_plane_xy ? boundingbox_X.max() : boundingbox_X.min(),
90 boundingbox_Y.middle());
92 //Geom::Point orig = Geom::Point(bounds_X.min(), bounds_Y.middle());
93 //orig = Geom::Point(orig[X], sp_document_height(inkscape_active_document()) - orig[Y]);
95 //double offset = uses_plane_xy ? boundingbox_X.extent() : 0.0;
97 /**
98 g_print ("Orig: (%8.2f, %8.2f)\n", orig[X], orig[Y]);
100 g_print ("B[1] - orig[1]: %8.2f\n", (B[1] - orig[1])[0].valueAt(0));
101 g_print ("B[0] - orig[0]: %8.2f\n", (B[0] - orig[0])[0].valueAt(0));
102 **/
104 if (uses_plane_xy) {
105 preimage[0] = (-B[0] + orig[0]) * scalex / 200.0;
106 preimage[1] = ( B[1] - orig[1]) * scaley / 400.0;
107 preimage[2] = B[0] - B[0]; // hack!
108 } else {
109 preimage[0] = B[0] - B[0]; // hack!
110 preimage[1] = (B[1] - orig[1]) * scaley / 400.0;
111 preimage[2] = (B[0] - orig[0]) * scalex / 200.0;
112 }
114 /* set perspective origin to first point of path */
115 tmat[0][3] = orig[0];
116 tmat[1][3] = orig[1];
118 /**
119 g_print ("preimage[1]: %8.2f\n", preimage[1][0].valueAt(0));
120 g_print ("preimage[2]: %8.2f\n", preimage[2][0].valueAt(0));
121 **/
123 Piecewise<SBasis> res[3];
124 for (int j = 0; j < 3; ++j) {
125 res[j] =
126 preimage[0] * tmat[j][0]
127 + preimage[1] * tmat[j][1]
128 + preimage[2] * tmat[j][2]
129 + tmat[j][3];
130 }
131 D2<Piecewise<SBasis> > result(divide(res[0],res[2], 3),
132 divide(res[1],res[2], 3));
134 Piecewise<D2<SBasis> > output = sectionize(result);
136 return output;
137 }
139 /* ######################## */
141 } //namespace LivePathEffect
142 } /* namespace Inkscape */
144 /*
145 Local Variables:
146 mode:c++
147 c-file-style:"stroustrup"
148 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
149 indent-tabs-mode:nil
150 fill-column:99
151 End:
152 */
153 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :