1 /** @file
2 * @brief LPE perspective path effect implementation.
3 */
4 /* Authors:
5 * Maximilian Albert <maximilian.albert@gmail.com>
6 * Johan Engelen <j.b.c.engelen@utwente.nl>
7 *
8 * Copyright (C) 2007-2008 Authors
9 *
10 * Released under GNU GPL, read the file 'COPYING' for more information
11 */
13 #include "persp3d.h"
14 //#include "transf_mat_3x4.h"
15 #include "document.h"
17 #include "live_effects/lpe-perspective_path.h"
18 #include "sp-item-group.h"
20 #include "inkscape.h"
22 #include <2geom/path.h>
24 namespace Inkscape {
25 namespace LivePathEffect {
27 namespace PP {
29 class KnotHolderEntityOffset : public LPEKnotHolderEntity
30 {
31 public:
32 virtual void knot_set(Geom::Point const &p, Geom::Point const &origin, guint state);
33 virtual Geom::Point knot_get();
34 };
36 } // namespace PP
38 LPEPerspectivePath::LPEPerspectivePath(LivePathEffectObject *lpeobject) :
39 Effect(lpeobject),
40 // initialise your parameters here:
41 scalex(_("Scale x"), _("Scale factor in x direction"), "scalex", &wr, this, 1.0),
42 scaley(_("Scale y"), _("Scale factor in y direction"), "scaley", &wr, this, 1.0),
43 offsetx(_("Offset x"), _("Offset in x direction"), "offsetx", &wr, this, 0.0),
44 offsety(_("Offset y"), _("Offset in y direction"), "offsety", &wr, this, 0.0),
45 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)
46 {
47 // register all your parameters here, so Inkscape knows which parameters this effect has:
48 registerParameter( dynamic_cast<Parameter *>(&scalex) );
49 registerParameter( dynamic_cast<Parameter *>(&scaley) );
50 registerParameter( dynamic_cast<Parameter *>(&offsetx) );
51 registerParameter( dynamic_cast<Parameter *>(&offsety) );
52 registerParameter( dynamic_cast<Parameter *>(&uses_plane_xy) );
54 registerKnotHolderHandle(new PP::KnotHolderEntityOffset(), _("Adjust the origin"));
56 concatenate_before_pwd2 = true; // don't split the path into its subpaths
58 Persp3D *persp = persp3d_document_first_persp(inkscape_active_document());
60 Proj::TransfMat3x4 pmat = persp->tmat;
62 pmat.copy_tmat(tmat);
63 }
65 LPEPerspectivePath::~LPEPerspectivePath()
66 {
68 }
70 void
71 LPEPerspectivePath::doBeforeEffect (SPLPEItem *lpeitem)
72 {
73 original_bbox(lpeitem, true);
74 }
76 Geom::Piecewise<Geom::D2<Geom::SBasis> >
77 LPEPerspectivePath::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
78 {
79 using namespace Geom;
81 Piecewise<D2<SBasis> > path_a_pw = pwd2_in;
83 // FIXME: the minus sign is there because the SVG coordinate system goes down;
84 // remove this once we have unified coordinate systems
85 path_a_pw = path_a_pw + Geom::Point(offsetx, -offsety);
87 D2<Piecewise<SBasis> > B = make_cuts_independent(path_a_pw);
88 Piecewise<SBasis> preimage[4];
90 //Geom::Point orig = Geom::Point(bounds_X.min(), bounds_Y.middle());
91 //orig = Geom::Point(orig[X], sp_document_height(inkscape_active_document()) - orig[Y]);
93 //double offset = uses_plane_xy ? boundingbox_X.extent() : 0.0;
95 orig = Point(uses_plane_xy ? boundingbox_X.max() : boundingbox_X.min(), boundingbox_Y.middle());
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 namespace PP {
141 // TODO: make this more generic
142 static LPEPerspectivePath *
143 get_effect(SPItem *item)
144 {
145 Effect *effect = sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item));
146 if (effect->effectType() != PERSPECTIVE_PATH) {
147 g_print ("Warning: Effect is not of type LPEPerspectivePath!\n");
148 return NULL;
149 }
150 return static_cast<LPEPerspectivePath *>(effect);
151 }
153 void
154 KnotHolderEntityOffset::knot_set(Geom::Point const &p, Geom::Point const &origin, guint /*state*/)
155 {
156 using namespace Geom;
158 LPEPerspectivePath* lpe = get_effect(item);
160 Geom::Point const s = snap_knot_position(p);
162 lpe->offsetx.param_set_value((s - origin)[Geom::X]);
163 lpe->offsety.param_set_value(-(s - origin)[Geom::Y]); // additional minus sign is due to coordinate system flipping
165 // FIXME: this should not directly ask for updating the item. It should write to SVG, which triggers updating.
166 sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true);
167 }
169 Geom::Point
170 KnotHolderEntityOffset::knot_get()
171 {
172 LPEPerspectivePath* lpe = get_effect(item);
173 return lpe->orig + Geom::Point(lpe->offsetx, -lpe->offsety);
174 }
176 } // namespace PP
178 } //namespace LivePathEffect
179 } /* namespace Inkscape */
181 /*
182 Local Variables:
183 mode:c++
184 c-file-style:"stroustrup"
185 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
186 indent-tabs-mode:nil
187 fill-column:99
188 End:
189 */
190 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :