1 #define __SP_BOX3D_C__
3 /*
4 * SVG <box3d> implementation
5 *
6 * Authors:
7 * Maximilian Albert <Anhalter42@gmx.de>
8 * Lauris Kaplinski <lauris@kaplinski.com>
9 * bulia byak <buliabyak@users.sf.net>
10 *
11 * Copyright (C) 2007 Authors
12 * Copyright (C) 1999-2002 Lauris Kaplinski
13 * Copyright (C) 2000-2001 Ximian, Inc.
14 *
15 * Released under GNU GPL, read the file 'COPYING' for more information
16 */
18 #include <glibmm/i18n.h>
19 #include "attributes.h"
20 #include "xml/document.h"
21 #include "xml/repr.h"
23 #include "box3d.h"
24 #include "box3d-side.h"
25 #include "box3d-context.h"
26 #include "proj_pt.h"
27 #include "transf_mat_3x4.h"
28 #include "perspective-line.h"
29 #include "inkscape.h"
30 #include "persp3d.h"
31 #include "line-geometry.h"
32 #include "persp3d-reference.h"
33 #include "uri.h"
34 #include <2geom/line.h>
35 #include "sp-guide.h"
36 #include "sp-namedview.h"
37 #include "preferences.h"
39 #include "desktop.h"
40 #include "desktop-handles.h"
41 #include "macros.h"
43 static void box3d_class_init(SPBox3DClass *klass);
44 static void box3d_init(SPBox3D *box3d);
46 static void box3d_build(SPObject *object, SPDocument *document, Inkscape::XML::Node *repr);
47 static void box3d_release(SPObject *object);
48 static void box3d_set(SPObject *object, unsigned int key, const gchar *value);
49 static void box3d_update(SPObject *object, SPCtx *ctx, guint flags);
50 static Inkscape::XML::Node *box3d_write(SPObject *object, Inkscape::XML::Document *doc, Inkscape::XML::Node *repr, guint flags);
52 static gchar *box3d_description(SPItem *item);
53 static Geom::Matrix box3d_set_transform(SPItem *item, Geom::Matrix const &xform);
54 static void box3d_convert_to_guides(SPItem *item);
56 static void box3d_ref_changed(SPObject *old_ref, SPObject *ref, SPBox3D *box);
58 static SPGroupClass *parent_class;
60 static gint counter = 0;
62 GType
63 box3d_get_type(void)
64 {
65 static GType type = 0;
67 if (!type) {
68 GTypeInfo info = {
69 sizeof(SPBox3DClass),
70 NULL, /* base_init */
71 NULL, /* base_finalize */
72 (GClassInitFunc) box3d_class_init,
73 NULL, /* class_finalize */
74 NULL, /* class_data */
75 sizeof(SPBox3D),
76 16, /* n_preallocs */
77 (GInstanceInitFunc) box3d_init,
78 NULL, /* value_table */
79 };
80 type = g_type_register_static(SP_TYPE_GROUP, "SPBox3D", &info, (GTypeFlags) 0);
81 }
83 return type;
84 }
86 static void
87 box3d_class_init(SPBox3DClass *klass)
88 {
89 SPObjectClass *sp_object_class = (SPObjectClass *) klass;
90 SPItemClass *item_class = (SPItemClass *) klass;
92 parent_class = (SPGroupClass *) g_type_class_ref(SP_TYPE_GROUP);
94 sp_object_class->build = box3d_build;
95 sp_object_class->release = box3d_release;
96 sp_object_class->set = box3d_set;
97 sp_object_class->write = box3d_write;
98 sp_object_class->update = box3d_update;
100 item_class->description = box3d_description;
101 item_class->set_transform = box3d_set_transform;
102 item_class->convert_to_guides = box3d_convert_to_guides;
103 }
105 static void
106 box3d_init(SPBox3D *box)
107 {
108 box->persp_href = NULL;
109 box->persp_ref = new Persp3DReference(SP_OBJECT(box));
110 }
112 static void
113 box3d_build(SPObject *object, SPDocument *document, Inkscape::XML::Node *repr)
114 {
115 if (((SPObjectClass *) (parent_class))->build) {
116 ((SPObjectClass *) (parent_class))->build(object, document, repr);
117 }
119 SPBox3D *box = SP_BOX3D (object);
120 box->my_counter = counter++;
122 /* we initialize the z-orders to zero so that they are updated during dragging */
123 for (int i = 0; i < 6; ++i) {
124 box->z_orders[i] = 0;
125 }
127 // TODO: Create/link to the correct perspective
129 SPDocument *doc = SP_OBJECT_DOCUMENT(box);
130 if (!doc)
131 return;
133 box->persp_ref->changedSignal().connect(sigc::bind(sigc::ptr_fun(box3d_ref_changed), box));
135 object->readAttr( "inkscape:perspectiveID");
136 object->readAttr( "inkscape:corner0");
137 object->readAttr( "inkscape:corner7");
138 }
140 /**
141 * Virtual release of SPBox3D members before destruction.
142 */
143 static void
144 box3d_release(SPObject *object)
145 {
146 SPBox3D *box = (SPBox3D *) object;
148 if (box->persp_href) {
149 g_free(box->persp_href);
150 }
152 // We have to store this here because the Persp3DReference gets destroyed below, but we need to
153 // access it to call persp3d_remove_box(), which cannot be called earlier because the reference
154 // needs to be destroyed first.
155 Persp3D *persp = box3d_get_perspective(box);
157 if (box->persp_ref) {
158 box->persp_ref->detach();
159 delete box->persp_ref;
160 box->persp_ref = NULL;
161 }
163 if (persp) {
164 persp3d_remove_box (persp, box);
165 /*
166 // TODO: This deletes a perspective when the last box referring to it is gone. Eventually,
167 // it would be nice to have this but currently it crashes when undoing/redoing box deletion
168 // Reason: When redoing a box deletion, the associated perspective is deleted twice, first
169 // by the following code and then again by the redo mechanism! Perhaps we should perform
170 // deletion of the perspective from another location "outside" the undo/redo mechanism?
171 if (persp->perspective_impl->boxes.empty()) {
172 SPDocument *doc = SP_OBJECT_DOCUMENT(box);
173 persp->deleteObject();
174 doc->setCurrentPersp3D(persp3d_document_first_persp(doc));
175 }
176 */
177 }
179 if (((SPObjectClass *) parent_class)->release)
180 ((SPObjectClass *) parent_class)->release(object);
181 }
183 static void
184 box3d_set(SPObject *object, unsigned int key, const gchar *value)
185 {
186 SPBox3D *box = SP_BOX3D(object);
188 switch (key) {
189 case SP_ATTR_INKSCAPE_BOX3D_PERSPECTIVE_ID:
190 if ( value && box->persp_href && ( strcmp(value, box->persp_href) == 0 ) ) {
191 /* No change, do nothing. */
192 } else {
193 if (box->persp_href) {
194 g_free(box->persp_href);
195 box->persp_href = NULL;
196 }
197 if (value) {
198 box->persp_href = g_strdup(value);
200 // Now do the attaching, which emits the changed signal.
201 try {
202 box->persp_ref->attach(Inkscape::URI(value));
203 } catch (Inkscape::BadURIException &e) {
204 g_warning("%s", e.what());
205 box->persp_ref->detach();
206 }
207 } else {
208 // Detach, which emits the changed signal.
209 box->persp_ref->detach();
210 }
211 }
213 // FIXME: Is the following update doubled by some call in either persp3d.cpp or vanishing_point_new.cpp?
214 box3d_position_set(box);
215 break;
216 case SP_ATTR_INKSCAPE_BOX3D_CORNER0:
217 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
218 box->orig_corner0 = Proj::Pt3(value);
219 box->save_corner0 = box->orig_corner0;
220 box3d_position_set(box);
221 }
222 break;
223 case SP_ATTR_INKSCAPE_BOX3D_CORNER7:
224 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
225 box->orig_corner7 = Proj::Pt3(value);
226 box->save_corner7 = box->orig_corner7;
227 box3d_position_set(box);
228 }
229 break;
230 default:
231 if (((SPObjectClass *) (parent_class))->set) {
232 ((SPObjectClass *) (parent_class))->set(object, key, value);
233 }
234 break;
235 }
236 }
238 /**
239 * Gets called when (re)attached to another perspective.
240 */
241 static void
242 box3d_ref_changed(SPObject *old_ref, SPObject *ref, SPBox3D *box)
243 {
244 if (old_ref) {
245 sp_signal_disconnect_by_data(old_ref, box);
246 persp3d_remove_box (SP_PERSP3D(old_ref), box);
247 }
248 if ( SP_IS_PERSP3D(ref) && ref != box ) // FIXME: Comparisons sane?
249 {
250 persp3d_add_box (SP_PERSP3D(ref), box);
251 }
252 }
254 static void
255 box3d_update(SPObject *object, SPCtx *ctx, guint flags)
256 {
257 if (flags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG | SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
259 /* FIXME?: Perhaps the display updates of box sides should be instantiated from here, but this
260 causes evil update loops so it's all done from box3d_position_set, which is called from
261 various other places (like the handlers in object-edit.cpp, vanishing-point.cpp, etc. */
263 }
265 // Invoke parent method
266 if (((SPObjectClass *) (parent_class))->update)
267 ((SPObjectClass *) (parent_class))->update(object, ctx, flags);
268 }
271 static Inkscape::XML::Node * box3d_write(SPObject *object, Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags)
272 {
273 SPBox3D *box = SP_BOX3D(object);
275 if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
276 // this is where we end up when saving as plain SVG (also in other circumstances?)
277 // thus we don' set "sodipodi:type" so that the box is only saved as an ordinary svg:g
278 repr = xml_doc->createElement("svg:g");
279 }
281 if (flags & SP_OBJECT_WRITE_EXT) {
283 if (box->persp_href) {
284 repr->setAttribute("inkscape:perspectiveID", box->persp_href);
285 } else {
286 /* box is not yet linked to a perspective; use the document's current perspective */
287 SPDocument *doc = SP_OBJECT_DOCUMENT(object);
288 if (box->persp_ref->getURI()) {
289 gchar *uri_string = box->persp_ref->getURI()->toString();
290 repr->setAttribute("inkscape:perspectiveID", uri_string);
291 g_free(uri_string);
292 } else {
293 //Inkscape::XML::Node *persp_repr = SP_OBJECT_REPR(doc->getCurrentPersp3D());
294 //const gchar *persp_id = persp_repr->attribute("id");
295 //gchar *href = g_strdup_printf("#%s", persp_id);
296 Glib::ustring href = "#";
297 href += doc->getCurrentPersp3D()->getId();
298 repr->setAttribute("inkscape:perspectiveID", href.c_str());
299 //g_free(href);
300 }
301 }
303 gchar *coordstr0 = box->orig_corner0.coord_string();
304 gchar *coordstr7 = box->orig_corner7.coord_string();
305 repr->setAttribute("inkscape:corner0", coordstr0);
306 repr->setAttribute("inkscape:corner7", coordstr7);
307 g_free(coordstr0);
308 g_free(coordstr7);
310 box->orig_corner0.normalize();
311 box->orig_corner7.normalize();
313 box->save_corner0 = box->orig_corner0;
314 box->save_corner7 = box->orig_corner7;
315 }
317 if (((SPObjectClass *) (parent_class))->write) {
318 ((SPObjectClass *) (parent_class))->write(object, xml_doc, repr, flags);
319 }
321 return repr;
322 }
324 static gchar *
325 box3d_description(SPItem *item)
326 {
327 g_return_val_if_fail(SP_IS_BOX3D(item), NULL);
329 return g_strdup(_("<b>3D Box</b>"));
330 }
332 void
333 box3d_position_set (SPBox3D *box)
334 {
335 /* This draws the curve and calls requestDisplayUpdate() for each side (the latter is done in
336 box3d_side_position_set() to avoid update conflicts with the parent box) */
337 for (SPObject *child = SP_OBJECT (box)->first_child(); child != NULL; child = SP_OBJECT_NEXT(child) ) {
338 if (SP_IS_BOX3D_SIDE(child))
339 box3d_side_position_set(SP_BOX3D_SIDE(child));
340 }
341 }
343 static Geom::Matrix
344 box3d_set_transform(SPItem *item, Geom::Matrix const &xform)
345 {
346 SPBox3D *box = SP_BOX3D(item);
348 // We don't apply the transform to the box directly but instead to its perspective (which is
349 // done in sp_selection_apply_affine). Here we only adjust strokes, patterns, etc.
351 Geom::Matrix ret(Geom::Matrix(xform).without_translation());
352 gdouble const sw = hypot(ret[0], ret[1]);
353 gdouble const sh = hypot(ret[2], ret[3]);
355 for (SPObject *child = box->first_child(); child != NULL; child = SP_OBJECT_NEXT(child)) {
356 if (SP_IS_ITEM(child)) {
357 SPItem *childitem = SP_ITEM(child);
359 // Adjust stroke width
360 childitem->adjust_stroke(sqrt(fabs(sw * sh)));
362 // Adjust pattern fill
363 childitem->adjust_pattern(xform);
365 // Adjust gradient fill
366 childitem->adjust_gradient(xform);
368 // Adjust LPE
369 childitem->adjust_livepatheffect(xform);
370 }
371 }
373 return Geom::identity();
374 }
376 Proj::Pt3
377 box3d_get_proj_corner (guint id, Proj::Pt3 const &c0, Proj::Pt3 const &c7) {
378 return Proj::Pt3 ((id & Box3D::X) ? c7[Proj::X] : c0[Proj::X],
379 (id & Box3D::Y) ? c7[Proj::Y] : c0[Proj::Y],
380 (id & Box3D::Z) ? c7[Proj::Z] : c0[Proj::Z],
381 1.0);
382 }
384 Proj::Pt3
385 box3d_get_proj_corner (SPBox3D const *box, guint id) {
386 return Proj::Pt3 ((id & Box3D::X) ? box->orig_corner7[Proj::X] : box->orig_corner0[Proj::X],
387 (id & Box3D::Y) ? box->orig_corner7[Proj::Y] : box->orig_corner0[Proj::Y],
388 (id & Box3D::Z) ? box->orig_corner7[Proj::Z] : box->orig_corner0[Proj::Z],
389 1.0);
390 }
392 Geom::Point
393 box3d_get_corner_screen (SPBox3D const *box, guint id, bool item_coords) {
394 Proj::Pt3 proj_corner (box3d_get_proj_corner (box, id));
395 if (!box3d_get_perspective(box)) {
396 return Geom::Point (NR_HUGE, NR_HUGE);
397 }
398 Geom::Matrix const i2d (SP_ITEM(box)->i2d_affine ());
399 if (item_coords) {
400 return box3d_get_perspective(box)->perspective_impl->tmat.image(proj_corner).affine() * i2d.inverse();
401 } else {
402 return box3d_get_perspective(box)->perspective_impl->tmat.image(proj_corner).affine();
403 }
404 }
406 Proj::Pt3
407 box3d_get_proj_center (SPBox3D *box) {
408 box->orig_corner0.normalize();
409 box->orig_corner7.normalize();
410 return Proj::Pt3 ((box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2,
411 (box->orig_corner0[Proj::Y] + box->orig_corner7[Proj::Y]) / 2,
412 (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2,
413 1.0);
414 }
416 Geom::Point
417 box3d_get_center_screen (SPBox3D *box) {
418 Proj::Pt3 proj_center (box3d_get_proj_center (box));
419 if (!box3d_get_perspective(box)) {
420 return Geom::Point (NR_HUGE, NR_HUGE);
421 }
422 Geom::Matrix const i2d (SP_ITEM(box)->i2d_affine ());
423 return box3d_get_perspective(box)->perspective_impl->tmat.image(proj_center).affine() * i2d.inverse();
424 }
426 /*
427 * To keep the snappoint from jumping randomly between the two lines when the mouse pointer is close to
428 * their intersection, we remember the last snapped line and keep snapping to this specific line as long
429 * as the distance from the intersection to the mouse pointer is less than remember_snap_threshold.
430 */
432 // Should we make the threshold settable in the preferences?
433 static double remember_snap_threshold = 30;
434 static guint remember_snap_index = 0;
436 static Proj::Pt3
437 box3d_snap (SPBox3D *box, int id, Proj::Pt3 const &pt_proj, Proj::Pt3 const &start_pt) {
438 double z_coord = start_pt[Proj::Z];
439 double diff_x = box->save_corner7[Proj::X] - box->save_corner0[Proj::X];
440 double diff_y = box->save_corner7[Proj::Y] - box->save_corner0[Proj::Y];
441 double x_coord = start_pt[Proj::X];
442 double y_coord = start_pt[Proj::Y];
443 Proj::Pt3 A_proj (x_coord, y_coord, z_coord, 1.0);
444 Proj::Pt3 B_proj (x_coord + diff_x, y_coord, z_coord, 1.0);
445 Proj::Pt3 C_proj (x_coord + diff_x, y_coord + diff_y, z_coord, 1.0);
446 Proj::Pt3 D_proj (x_coord, y_coord + diff_y, z_coord, 1.0);
447 Proj::Pt3 E_proj (x_coord - diff_x, y_coord + diff_y, z_coord, 1.0);
449 Persp3DImpl *persp_impl = box3d_get_perspective(box)->perspective_impl;
450 Geom::Point A = persp_impl->tmat.image(A_proj).affine();
451 Geom::Point B = persp_impl->tmat.image(B_proj).affine();
452 Geom::Point C = persp_impl->tmat.image(C_proj).affine();
453 Geom::Point D = persp_impl->tmat.image(D_proj).affine();
454 Geom::Point E = persp_impl->tmat.image(E_proj).affine();
455 Geom::Point pt = persp_impl->tmat.image(pt_proj).affine();
457 // TODO: Replace these lines between corners with lines from a corner to a vanishing point
458 // (this might help to prevent rounding errors if the box is small)
459 Box3D::Line pl1(A, B);
460 Box3D::Line pl2(A, D);
461 Box3D::Line diag1(A, (id == -1 || (!(id & Box3D::X) == !(id & Box3D::Y))) ? C : E);
462 Box3D::Line diag2(A, E); // diag2 is only taken into account if id equals -1, i.e., if we are snapping the center
464 int num_snap_lines = (id != -1) ? 3 : 4;
465 Geom::Point snap_pts[num_snap_lines];
467 snap_pts[0] = pl1.closest_to (pt);
468 snap_pts[1] = pl2.closest_to (pt);
469 snap_pts[2] = diag1.closest_to (pt);
470 if (id == -1) {
471 snap_pts[3] = diag2.closest_to (pt);
472 }
474 gdouble const zoom = inkscape_active_desktop()->current_zoom();
476 // determine the distances to all potential snapping points
477 double snap_dists[num_snap_lines];
478 for (int i = 0; i < num_snap_lines; ++i) {
479 snap_dists[i] = Geom::L2 (snap_pts[i] - pt) * zoom;
480 }
482 // while we are within a given tolerance of the starting point,
483 // keep snapping to the same point to avoid jumping
484 bool within_tolerance = true;
485 for (int i = 0; i < num_snap_lines; ++i) {
486 if (snap_dists[i] > remember_snap_threshold) {
487 within_tolerance = false;
488 break;
489 }
490 }
492 // find the closest snapping point
493 int snap_index = -1;
494 double snap_dist = NR_HUGE;
495 for (int i = 0; i < num_snap_lines; ++i) {
496 if (snap_dists[i] < snap_dist) {
497 snap_index = i;
498 snap_dist = snap_dists[i];
499 }
500 }
502 // snap to the closest point (or the previously remembered one
503 // if we are within tolerance of the starting point)
504 Geom::Point result;
505 if (within_tolerance) {
506 result = snap_pts[remember_snap_index];
507 } else {
508 remember_snap_index = snap_index;
509 result = snap_pts[snap_index];
510 }
511 return box3d_get_perspective(box)->perspective_impl->tmat.preimage (result, z_coord, Proj::Z);
512 }
514 /*create a SPBox3D and append it to the parent*/
516 SPBox3D * SPBox3D::createBox3D(SPItem * parent)
517 {
518 SPBox3D *box3d = 0;
519 Inkscape::XML::Document *xml_doc = parent->document->rdoc;
520 Inkscape::XML::Node *repr = xml_doc->createElement("svg:g");
521 repr->setAttribute("sodipodi:type", "inkscape:box3d");
522 box3d = (SPBox3D *)parent->appendChildRepr(repr);
523 return box3d;
524 }
526 void
527 box3d_set_corner (SPBox3D *box, const guint id, Geom::Point const &new_pos, const Box3D::Axis movement, bool constrained) {
528 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
530 box->orig_corner0.normalize();
531 box->orig_corner7.normalize();
533 /* update corners 0 and 7 according to which handle was moved and to the axes of movement */
534 if (!(movement & Box3D::Z)) {
535 Persp3DImpl *persp_impl = box3d_get_perspective(box)->perspective_impl;
536 Proj::Pt3 pt_proj (persp_impl->tmat.preimage (new_pos, (id < 4) ? box->orig_corner0[Proj::Z] :
537 box->orig_corner7[Proj::Z], Proj::Z));
538 if (constrained) {
539 pt_proj = box3d_snap (box, id, pt_proj, box3d_get_proj_corner (id, box->save_corner0, box->save_corner7));
540 }
542 // normalizing pt_proj is essential because we want to mingle affine coordinates
543 pt_proj.normalize();
544 box->orig_corner0 = Proj::Pt3 ((id & Box3D::X) ? box->save_corner0[Proj::X] : pt_proj[Proj::X],
545 (id & Box3D::Y) ? box->save_corner0[Proj::Y] : pt_proj[Proj::Y],
546 box->save_corner0[Proj::Z],
547 1.0);
548 box->orig_corner7 = Proj::Pt3 ((id & Box3D::X) ? pt_proj[Proj::X] : box->save_corner7[Proj::X],
549 (id & Box3D::Y) ? pt_proj[Proj::Y] : box->save_corner7[Proj::Y],
550 box->save_corner7[Proj::Z],
551 1.0);
552 } else {
553 Persp3D *persp = box3d_get_perspective(box);
554 Persp3DImpl *persp_impl = box3d_get_perspective(box)->perspective_impl;
555 Box3D::PerspectiveLine pl(persp_impl->tmat.image(
556 box3d_get_proj_corner (id, box->save_corner0, box->save_corner7)).affine(),
557 Proj::Z, persp);
558 Geom::Point new_pos_snapped(pl.closest_to(new_pos));
559 Proj::Pt3 pt_proj (persp_impl->tmat.preimage (new_pos_snapped,
560 box3d_get_proj_corner (box, id)[(movement & Box3D::Y) ? Proj::X : Proj::Y],
561 (movement & Box3D::Y) ? Proj::X : Proj::Y));
562 bool corner0_move_x = !(id & Box3D::X) && (movement & Box3D::X);
563 bool corner0_move_y = !(id & Box3D::Y) && (movement & Box3D::Y);
564 bool corner7_move_x = (id & Box3D::X) && (movement & Box3D::X);
565 bool corner7_move_y = (id & Box3D::Y) && (movement & Box3D::Y);
566 // normalizing pt_proj is essential because we want to mingle affine coordinates
567 pt_proj.normalize();
568 box->orig_corner0 = Proj::Pt3 (corner0_move_x ? pt_proj[Proj::X] : box->orig_corner0[Proj::X],
569 corner0_move_y ? pt_proj[Proj::Y] : box->orig_corner0[Proj::Y],
570 (id & Box3D::Z) ? box->orig_corner0[Proj::Z] : pt_proj[Proj::Z],
571 1.0);
572 box->orig_corner7 = Proj::Pt3 (corner7_move_x ? pt_proj[Proj::X] : box->orig_corner7[Proj::X],
573 corner7_move_y ? pt_proj[Proj::Y] : box->orig_corner7[Proj::Y],
574 (id & Box3D::Z) ? pt_proj[Proj::Z] : box->orig_corner7[Proj::Z],
575 1.0);
576 }
577 // FIXME: Should we update the box here? If so, how?
578 }
580 void box3d_set_center (SPBox3D *box, Geom::Point const &new_pos, Geom::Point const &old_pos, const Box3D::Axis movement, bool constrained) {
581 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
583 box->orig_corner0.normalize();
584 box->orig_corner7.normalize();
586 Persp3D *persp = box3d_get_perspective(box);
587 if (!(movement & Box3D::Z)) {
588 double coord = (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2;
589 double radx = (box->orig_corner7[Proj::X] - box->orig_corner0[Proj::X]) / 2;
590 double rady = (box->orig_corner7[Proj::Y] - box->orig_corner0[Proj::Y]) / 2;
592 Proj::Pt3 pt_proj (persp->perspective_impl->tmat.preimage (new_pos, coord, Proj::Z));
593 if (constrained) {
594 Proj::Pt3 old_pos_proj (persp->perspective_impl->tmat.preimage (old_pos, coord, Proj::Z));
595 old_pos_proj.normalize();
596 pt_proj = box3d_snap (box, -1, pt_proj, old_pos_proj);
597 }
598 // normalizing pt_proj is essential because we want to mingle affine coordinates
599 pt_proj.normalize();
600 box->orig_corner0 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] - radx : box->orig_corner0[Proj::X],
601 (movement & Box3D::Y) ? pt_proj[Proj::Y] - rady : box->orig_corner0[Proj::Y],
602 box->orig_corner0[Proj::Z],
603 1.0);
604 box->orig_corner7 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] + radx : box->orig_corner7[Proj::X],
605 (movement & Box3D::Y) ? pt_proj[Proj::Y] + rady : box->orig_corner7[Proj::Y],
606 box->orig_corner7[Proj::Z],
607 1.0);
608 } else {
609 double coord = (box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2;
610 double radz = (box->orig_corner7[Proj::Z] - box->orig_corner0[Proj::Z]) / 2;
612 Box3D::PerspectiveLine pl(old_pos, Proj::Z, persp);
613 Geom::Point new_pos_snapped(pl.closest_to(new_pos));
614 Proj::Pt3 pt_proj (persp->perspective_impl->tmat.preimage (new_pos_snapped, coord, Proj::X));
616 /* normalizing pt_proj is essential because we want to mingle affine coordinates */
617 pt_proj.normalize();
618 box->orig_corner0 = Proj::Pt3 (box->orig_corner0[Proj::X],
619 box->orig_corner0[Proj::Y],
620 pt_proj[Proj::Z] - radz,
621 1.0);
622 box->orig_corner7 = Proj::Pt3 (box->orig_corner7[Proj::X],
623 box->orig_corner7[Proj::Y],
624 pt_proj[Proj::Z] + radz,
625 1.0);
626 }
627 }
629 /*
630 * Manipulates corner1 through corner4 to contain the indices of the corners
631 * from which the perspective lines in the direction of 'axis' emerge
632 */
633 void box3d_corners_for_PLs (const SPBox3D * box, Proj::Axis axis,
634 Geom::Point &corner1, Geom::Point &corner2, Geom::Point &corner3, Geom::Point &corner4)
635 {
636 Persp3D *persp = box3d_get_perspective(box);
637 g_return_if_fail (persp);
638 Persp3DImpl *persp_impl = persp->perspective_impl;
639 //box->orig_corner0.normalize();
640 //box->orig_corner7.normalize();
641 double coord = (box->orig_corner0[axis] > box->orig_corner7[axis]) ?
642 box->orig_corner0[axis] :
643 box->orig_corner7[axis];
645 Proj::Pt3 c1, c2, c3, c4;
646 // FIXME: This can certainly be done more elegantly/efficiently than by a case-by-case analysis.
647 switch (axis) {
648 case Proj::X:
649 c1 = Proj::Pt3 (coord, box->orig_corner0[Proj::Y], box->orig_corner0[Proj::Z], 1.0);
650 c2 = Proj::Pt3 (coord, box->orig_corner7[Proj::Y], box->orig_corner0[Proj::Z], 1.0);
651 c3 = Proj::Pt3 (coord, box->orig_corner7[Proj::Y], box->orig_corner7[Proj::Z], 1.0);
652 c4 = Proj::Pt3 (coord, box->orig_corner0[Proj::Y], box->orig_corner7[Proj::Z], 1.0);
653 break;
654 case Proj::Y:
655 c1 = Proj::Pt3 (box->orig_corner0[Proj::X], coord, box->orig_corner0[Proj::Z], 1.0);
656 c2 = Proj::Pt3 (box->orig_corner7[Proj::X], coord, box->orig_corner0[Proj::Z], 1.0);
657 c3 = Proj::Pt3 (box->orig_corner7[Proj::X], coord, box->orig_corner7[Proj::Z], 1.0);
658 c4 = Proj::Pt3 (box->orig_corner0[Proj::X], coord, box->orig_corner7[Proj::Z], 1.0);
659 break;
660 case Proj::Z:
661 c1 = Proj::Pt3 (box->orig_corner7[Proj::X], box->orig_corner7[Proj::Y], coord, 1.0);
662 c2 = Proj::Pt3 (box->orig_corner7[Proj::X], box->orig_corner0[Proj::Y], coord, 1.0);
663 c3 = Proj::Pt3 (box->orig_corner0[Proj::X], box->orig_corner0[Proj::Y], coord, 1.0);
664 c4 = Proj::Pt3 (box->orig_corner0[Proj::X], box->orig_corner7[Proj::Y], coord, 1.0);
665 break;
666 default:
667 return;
668 }
669 corner1 = persp_impl->tmat.image(c1).affine();
670 corner2 = persp_impl->tmat.image(c2).affine();
671 corner3 = persp_impl->tmat.image(c3).affine();
672 corner4 = persp_impl->tmat.image(c4).affine();
673 }
675 /* Auxiliary function: Checks whether the half-line from A to B crosses the line segment joining C and D */
676 static bool
677 box3d_half_line_crosses_joining_line (Geom::Point const &A, Geom::Point const &B,
678 Geom::Point const &C, Geom::Point const &D) {
679 Geom::Point n0 = (B - A).ccw();
680 double d0 = dot(n0,A);
682 Geom::Point n1 = (D - C).ccw();
683 double d1 = dot(n1,C);
685 Geom::Line lineAB(A,B);
686 Geom::Line lineCD(C,D);
688 Geom::OptCrossing inters = Geom::OptCrossing(); // empty by default
689 try
690 {
691 inters = Geom::intersection(lineAB, lineCD);
692 }
693 catch (Geom::InfiniteSolutions e)
694 {
695 // We're probably dealing with parallel lines, so they don't really cross
696 return false;
697 }
699 if (!inters) {
700 return false;
701 }
703 Geom::Point E = lineAB.pointAt((*inters).ta); // the point of intersection
705 if ((dot(C,n0) < d0) == (dot(D,n0) < d0)) {
706 // C and D lie on the same side of the line AB
707 return false;
708 }
709 if ((dot(A,n1) < d1) != (dot(B,n1) < d1)) {
710 // A and B lie on different sides of the line CD
711 return true;
712 } else if (Geom::distance(E,A) < Geom::distance(E,B)) {
713 // The line CD passes on the "wrong" side of A
714 return false;
715 }
717 // The line CD passes on the "correct" side of A
718 return true;
719 }
721 static bool
722 box3d_XY_axes_are_swapped (SPBox3D *box) {
723 Persp3D *persp = box3d_get_perspective(box);
724 g_return_val_if_fail(persp, false);
725 Box3D::PerspectiveLine l1(box3d_get_corner_screen(box, 3, false), Proj::X, persp);
726 Box3D::PerspectiveLine l2(box3d_get_corner_screen(box, 3, false), Proj::Y, persp);
727 Geom::Point v1(l1.direction());
728 Geom::Point v2(l2.direction());
729 v1.normalize();
730 v2.normalize();
732 return (v1[Geom::X]*v2[Geom::Y] - v1[Geom::Y]*v2[Geom::X] > 0);
733 }
735 static inline void
736 box3d_aux_set_z_orders (int z_orders[6], int a, int b, int c, int d, int e, int f) {
737 z_orders[0] = a;
738 z_orders[1] = b;
739 z_orders[2] = c;
740 z_orders[3] = d;
741 z_orders[4] = e;
742 z_orders[5] = f;
743 }
745 static inline void
746 box3d_swap_z_orders (int z_orders[6]) {
747 int tmp;
748 for (int i = 0; i < 3; ++i) {
749 tmp = z_orders[i];
750 z_orders[i] = z_orders[5-i];
751 z_orders[5-i] = tmp;
752 }
753 }
755 /*
756 * In standard perspective we have:
757 * 2 = front face
758 * 1 = top face
759 * 0 = left face
760 * 3 = right face
761 * 4 = bottom face
762 * 5 = rear face
763 */
765 /* All VPs infinite */
766 static void
767 box3d_set_new_z_orders_case0 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis) {
768 Persp3D *persp = box3d_get_perspective(box);
769 Geom::Point xdir(persp3d_get_infinite_dir(persp, Proj::X));
770 Geom::Point ydir(persp3d_get_infinite_dir(persp, Proj::Y));
771 Geom::Point zdir(persp3d_get_infinite_dir(persp, Proj::Z));
773 bool swapped = box3d_XY_axes_are_swapped(box);
775 switch(central_axis) {
776 case Box3D::X:
777 if (!swapped) {
778 box3d_aux_set_z_orders (z_orders, 2, 0, 4, 1, 3, 5);
779 } else {
780 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 2, 4, 0);
781 }
782 break;
783 case Box3D::Y:
784 if (!swapped) {
785 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 4, 0, 5);
786 } else {
787 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
788 }
789 break;
790 case Box3D::Z:
791 if (!swapped) {
792 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
793 } else {
794 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 1, 0, 2);
795 }
796 break;
797 case Box3D::NONE:
798 if (!swapped) {
799 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
800 } else {
801 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 4, 3, 2);
802 }
803 break;
804 default:
805 g_assert_not_reached();
806 break;
807 }
808 }
810 /* Precisely one finite VP */
811 static void
812 box3d_set_new_z_orders_case1 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis, Box3D::Axis fin_axis) {
813 Persp3D *persp = box3d_get_perspective(box);
814 Geom::Point vp(persp3d_get_VP(persp, Box3D::toProj(fin_axis)).affine());
816 // note: in some of the case distinctions below we rely upon the fact that oaxis1 and oaxis2 are ordered
817 Box3D::Axis oaxis1 = Box3D::get_remaining_axes(fin_axis).first;
818 Box3D::Axis oaxis2 = Box3D::get_remaining_axes(fin_axis).second;
819 int inside1 = 0;
820 int inside2 = 0;
821 inside1 = box3d_pt_lies_in_PL_sector (box, vp, 3, 3 ^ oaxis2, oaxis1);
822 inside2 = box3d_pt_lies_in_PL_sector (box, vp, 3, 3 ^ oaxis1, oaxis2);
824 bool swapped = box3d_XY_axes_are_swapped(box);
826 switch(central_axis) {
827 case Box3D::X:
828 if (!swapped) {
829 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
830 } else {
831 box3d_aux_set_z_orders (z_orders, 5, 3, 1, 0, 2, 4);
832 }
833 break;
834 case Box3D::Y:
835 if (inside2 > 0) {
836 box3d_aux_set_z_orders (z_orders, 1, 2, 3, 0, 5, 4);
837 } else if (inside2 < 0) {
838 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 4, 0, 5);
839 } else {
840 if (!swapped) {
841 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
842 } else {
843 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
844 }
845 }
846 break;
847 case Box3D::Z:
848 if (inside2) {
849 if (!swapped) {
850 box3d_aux_set_z_orders (z_orders, 2, 1, 3, 0, 4, 5);
851 } else {
852 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 0, 1, 2);
853 }
854 } else if (inside1) {
855 if (!swapped) {
856 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
857 } else {
858 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 1, 0, 2);
859 }
860 } else {
861 // "regular" case
862 if (!swapped) {
863 box3d_aux_set_z_orders (z_orders, 0, 1, 2, 5, 4, 3);
864 } else {
865 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 0, 2, 1);
866 }
867 }
868 break;
869 case Box3D::NONE:
870 if (!swapped) {
871 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 5, 0, 1);
872 } else {
873 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 3, 2, 4);
874 }
875 break;
876 default:
877 g_assert_not_reached();
878 }
879 }
881 /* Precisely 2 finite VPs */
882 static void
883 box3d_set_new_z_orders_case2 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis, Box3D::Axis /*infinite_axis*/) {
884 Persp3D *persp = box3d_get_perspective(box);
886 Geom::Point c3(box3d_get_corner_screen(box, 3, false));
887 Geom::Point xdir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::X));
888 Geom::Point ydir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::Y));
889 Geom::Point zdir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::Z));
891 bool swapped = box3d_XY_axes_are_swapped(box);
893 int insidexy = box3d_VP_lies_in_PL_sector (box, Proj::X, 3, 3 ^ Box3D::Z, Box3D::Y);
894 //int insidexz = box3d_VP_lies_in_PL_sector (box, Proj::X, 3, 3 ^ Box3D::Y, Box3D::Z);
896 int insideyx = box3d_VP_lies_in_PL_sector (box, Proj::Y, 3, 3 ^ Box3D::Z, Box3D::X);
897 int insideyz = box3d_VP_lies_in_PL_sector (box, Proj::Y, 3, 3 ^ Box3D::X, Box3D::Z);
899 //int insidezx = box3d_VP_lies_in_PL_sector (box, Proj::Z, 3, 3 ^ Box3D::Y, Box3D::X);
900 int insidezy = box3d_VP_lies_in_PL_sector (box, Proj::Z, 3, 3 ^ Box3D::X, Box3D::Y);
902 switch(central_axis) {
903 case Box3D::X:
904 if (!swapped) {
905 if (insidezy == -1) {
906 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
907 } else if (insidexy == 1) {
908 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 5, 1, 3);
909 } else {
910 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
911 }
912 } else {
913 if (insideyz == -1) {
914 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 0, 2, 4);
915 } else {
916 if (!swapped) {
917 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 2, 4, 0);
918 } else {
919 if (insidexy == 0) {
920 box3d_aux_set_z_orders (z_orders, 3, 5, 1, 0, 2, 4);
921 } else {
922 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 0, 2, 4);
923 }
924 }
925 }
926 }
927 break;
928 case Box3D::Y:
929 if (!swapped) {
930 if (insideyz == 1) {
931 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 0, 5, 4);
932 } else {
933 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
934 }
935 } else {
936 if (insideyx == 1) {
937 box3d_aux_set_z_orders (z_orders, 4, 0, 5, 1, 3, 2);
938 } else {
939 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
940 }
941 }
942 break;
943 case Box3D::Z:
944 if (!swapped) {
945 if (insidezy == 1) {
946 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 4, 3, 5);
947 } else if (insidexy == -1) {
948 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 5, 4, 3);
949 } else {
950 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 5, 3, 4);
951 }
952 } else {
953 box3d_aux_set_z_orders (z_orders, 3, 4, 5, 1, 0, 2);
954 }
955 break;
956 case Box3D::NONE:
957 if (!swapped) {
958 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
959 } else {
960 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 4, 3, 2);
961 }
962 break;
963 default:
964 g_assert_not_reached();
965 break;
966 }
967 }
969 /*
970 * It can happen that during dragging the box is everted.
971 * In this case the opposite sides in this direction need to be swapped
972 */
973 static Box3D::Axis
974 box3d_everted_directions (SPBox3D *box) {
975 Box3D::Axis ev = Box3D::NONE;
977 box->orig_corner0.normalize();
978 box->orig_corner7.normalize();
980 if (box->orig_corner0[Proj::X] < box->orig_corner7[Proj::X])
981 ev = (Box3D::Axis) (ev ^ Box3D::X);
982 if (box->orig_corner0[Proj::Y] < box->orig_corner7[Proj::Y])
983 ev = (Box3D::Axis) (ev ^ Box3D::Y);
984 if (box->orig_corner0[Proj::Z] > box->orig_corner7[Proj::Z]) // FIXME: Remove the need to distinguish signs among the cases
985 ev = (Box3D::Axis) (ev ^ Box3D::Z);
987 return ev;
988 }
990 static void
991 box3d_swap_sides(int z_orders[6], Box3D::Axis axis) {
992 int pos1 = -1;
993 int pos2 = -1;
995 for (int i = 0; i < 6; ++i) {
996 if (!(Box3D::int_to_face(z_orders[i]) & axis)) {
997 if (pos1 == -1) {
998 pos1 = i;
999 } else {
1000 pos2 = i;
1001 break;
1002 }
1003 }
1004 }
1006 int tmp = z_orders[pos1];
1007 z_orders[pos1] = z_orders[pos2];
1008 z_orders[pos2] = tmp;
1009 }
1012 bool
1013 box3d_recompute_z_orders (SPBox3D *box) {
1014 Persp3D *persp = box3d_get_perspective(box);
1016 if (!persp)
1017 return false;
1019 int z_orders[6];
1021 Geom::Point c3(box3d_get_corner_screen(box, 3, false));
1023 // determine directions from corner3 to the VPs
1024 int num_finite = 0;
1025 Box3D::Axis axis_finite = Box3D::NONE;
1026 Box3D::Axis axis_infinite = Box3D::NONE;
1027 Geom::Point dirs[3];
1028 for (int i = 0; i < 3; ++i) {
1029 dirs[i] = persp3d_get_PL_dir_from_pt(persp, c3, Box3D::toProj(Box3D::axes[i]));
1030 if (persp3d_VP_is_finite(persp->perspective_impl, Proj::axes[i])) {
1031 num_finite++;
1032 axis_finite = Box3D::axes[i];
1033 } else {
1034 axis_infinite = Box3D::axes[i];
1035 }
1036 }
1038 // determine the "central" axis (if there is one)
1039 Box3D::Axis central_axis = Box3D::NONE;
1040 if(Box3D::lies_in_sector(dirs[0], dirs[1], dirs[2])) {
1041 central_axis = Box3D::Z;
1042 } else if(Box3D::lies_in_sector(dirs[1], dirs[2], dirs[0])) {
1043 central_axis = Box3D::X;
1044 } else if(Box3D::lies_in_sector(dirs[2], dirs[0], dirs[1])) {
1045 central_axis = Box3D::Y;
1046 }
1048 switch (num_finite) {
1049 case 0:
1050 // TODO: Remark: In this case (and maybe one of the others, too) the z-orders for all boxes
1051 // coincide, hence only need to be computed once in a more central location.
1052 box3d_set_new_z_orders_case0(box, z_orders, central_axis);
1053 break;
1054 case 1:
1055 box3d_set_new_z_orders_case1(box, z_orders, central_axis, axis_finite);
1056 break;
1057 case 2:
1058 case 3:
1059 box3d_set_new_z_orders_case2(box, z_orders, central_axis, axis_infinite);
1060 break;
1061 default:
1062 /*
1063 * For each VP F, check wether the half-line from the corner3 to F crosses the line segment
1064 * joining the other two VPs. If this is the case, it determines the "central" corner from
1065 * which the visible sides can be deduced. Otherwise, corner3 is the central corner.
1066 */
1067 // FIXME: We should eliminate the use of Geom::Point altogether
1068 Box3D::Axis central_axis = Box3D::NONE;
1069 Geom::Point vp_x = persp3d_get_VP(persp, Proj::X).affine();
1070 Geom::Point vp_y = persp3d_get_VP(persp, Proj::Y).affine();
1071 Geom::Point vp_z = persp3d_get_VP(persp, Proj::Z).affine();
1072 Geom::Point vpx(vp_x[Geom::X], vp_x[Geom::Y]);
1073 Geom::Point vpy(vp_y[Geom::X], vp_y[Geom::Y]);
1074 Geom::Point vpz(vp_z[Geom::X], vp_z[Geom::Y]);
1076 Geom::Point c3 = box3d_get_corner_screen(box, 3, false);
1077 Geom::Point corner3(c3[Geom::X], c3[Geom::Y]);
1079 if (box3d_half_line_crosses_joining_line (corner3, vpx, vpy, vpz)) {
1080 central_axis = Box3D::X;
1081 } else if (box3d_half_line_crosses_joining_line (corner3, vpy, vpz, vpx)) {
1082 central_axis = Box3D::Y;
1083 } else if (box3d_half_line_crosses_joining_line (corner3, vpz, vpx, vpy)) {
1084 central_axis = Box3D::Z;
1085 }
1087 unsigned int central_corner = 3 ^ central_axis;
1088 if (central_axis == Box3D::Z) {
1089 central_corner = central_corner ^ Box3D::XYZ;
1090 }
1091 if (box3d_XY_axes_are_swapped(box)) {
1092 central_corner = central_corner ^ Box3D::XYZ;
1093 }
1095 Geom::Point c1(box3d_get_corner_screen(box, 1, false));
1096 Geom::Point c2(box3d_get_corner_screen(box, 2, false));
1097 Geom::Point c7(box3d_get_corner_screen(box, 7, false));
1099 Geom::Point corner1(c1[Geom::X], c1[Geom::Y]);
1100 Geom::Point corner2(c2[Geom::X], c2[Geom::Y]);
1101 Geom::Point corner7(c7[Geom::X], c7[Geom::Y]);
1102 // FIXME: At present we don't use the information about central_corner computed above.
1103 switch (central_axis) {
1104 case Box3D::Y:
1105 if (!box3d_half_line_crosses_joining_line(vpz, vpy, corner3, corner2)) {
1106 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
1107 } else {
1108 // degenerate case
1109 box3d_aux_set_z_orders (z_orders, 2, 1, 3, 0, 5, 4);
1110 }
1111 break;
1113 case Box3D::Z:
1114 if (box3d_half_line_crosses_joining_line(vpx, vpz, corner3, corner1)) {
1115 // degenerate case
1116 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
1117 } else if (box3d_half_line_crosses_joining_line(vpx, vpy, corner3, corner7)) {
1118 // degenerate case
1119 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 5, 3, 4);
1120 } else {
1121 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 3, 4, 5);
1122 }
1123 break;
1125 case Box3D::X:
1126 if (box3d_half_line_crosses_joining_line(vpz, vpx, corner3, corner1)) {
1127 // degenerate case
1128 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 4, 5, 3);
1129 } else {
1130 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 5, 1, 3);
1131 }
1132 break;
1134 case Box3D::NONE:
1135 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
1136 break;
1138 default:
1139 g_assert_not_reached();
1140 break;
1141 } // end default case
1142 }
1144 // TODO: If there are still errors in z-orders of everted boxes, we need to choose a variable corner
1145 // instead of the hard-coded corner #3 in the computations above
1146 Box3D::Axis ev = box3d_everted_directions(box);
1147 for (int i = 0; i < 3; ++i) {
1148 if (ev & Box3D::axes[i]) {
1149 box3d_swap_sides(z_orders, Box3D::axes[i]);
1150 }
1151 }
1153 // Check whether anything actually changed
1154 for (int i = 0; i < 6; ++i) {
1155 if (box->z_orders[i] != z_orders[i]) {
1156 for (int j = i; j < 6; ++j) {
1157 box->z_orders[j] = z_orders[j];
1158 }
1159 return true;
1160 }
1161 }
1162 return false;
1163 }
1165 static std::map<int, Box3DSide *>
1166 box3d_get_sides (SPBox3D *box) {
1167 std::map<int, Box3DSide *> sides;
1168 for (SPObject *side = box->first_child(); side != NULL; side = SP_OBJECT_NEXT(side)) {
1170 if (SP_IS_BOX3D_SIDE(side)){
1171 Box3DSide *bside = SP_BOX3D_SIDE(side);
1172 sides[Box3D::face_to_int(bside->getFaceId())] = bside;
1173 }
1174 }
1175 sides.erase(-1);
1176 return sides;
1177 }
1180 // TODO: Check whether the box is everted in any direction and swap the sides opposite to this direction
1181 void
1182 box3d_set_z_orders (SPBox3D *box) {
1183 // For efficiency reasons, we only set the new z-orders if something really changed
1184 if (box3d_recompute_z_orders (box)) {
1185 std::map<int, Box3DSide *> sides = box3d_get_sides(box);
1186 std::map<int, Box3DSide *>::iterator side;
1187 for (unsigned int i = 0; i < 6; ++i) {
1188 side = sides.find(box->z_orders[i]);
1189 if (side != sides.end()) {
1190 SP_ITEM((*side).second)->lowerToBottom();
1191 }
1192 }
1193 }
1194 }
1196 /*
1197 * Auxiliary function for z-order recomputing:
1198 * Determines whether \a pt lies in the sector formed by the two PLs from the corners with IDs
1199 * \a i21 and \a id2 to the VP in direction \a axis. If the VP is infinite, we say that \a pt
1200 * lies in the sector if it lies between the two (parallel) PLs.
1201 * \ret * 0 if \a pt doesn't lie in the sector
1202 * * 1 if \a pt lies in the sector and either VP is finite of VP is infinite and the direction
1203 * from the edge between the two corners to \a pt points towards the VP
1204 * * -1 otherwise
1205 */
1206 // TODO: Maybe it would be useful to have a similar method for projective points pt because then we
1207 // can use it for VPs and perhaps merge the case distinctions during z-order recomputation.
1208 int
1209 box3d_pt_lies_in_PL_sector (SPBox3D const *box, Geom::Point const &pt, int id1, int id2, Box3D::Axis axis) {
1210 Persp3D *persp = box3d_get_perspective(box);
1212 // the two corners
1213 Geom::Point c1(box3d_get_corner_screen(box, id1, false));
1214 Geom::Point c2(box3d_get_corner_screen(box, id2, false));
1216 int ret = 0;
1217 if (persp3d_VP_is_finite(persp->perspective_impl, Box3D::toProj(axis))) {
1218 Geom::Point vp(persp3d_get_VP(persp, Box3D::toProj(axis)).affine());
1219 Geom::Point v1(c1 - vp);
1220 Geom::Point v2(c2 - vp);
1221 Geom::Point w(pt - vp);
1222 ret = static_cast<int>(Box3D::lies_in_sector(v1, v2, w));
1223 } else {
1224 Box3D::PerspectiveLine pl1(c1, Box3D::toProj(axis), persp);
1225 Box3D::PerspectiveLine pl2(c2, Box3D::toProj(axis), persp);
1226 if (pl1.lie_on_same_side(pt, c2) && pl2.lie_on_same_side(pt, c1)) {
1227 // test whether pt lies "towards" or "away from" the VP
1228 Box3D::Line edge(c1,c2);
1229 Geom::Point c3(box3d_get_corner_screen(box, id1 ^ axis, false));
1230 if (edge.lie_on_same_side(pt, c3)) {
1231 ret = 1;
1232 } else {
1233 ret = -1;
1234 }
1235 }
1236 }
1237 return ret;
1238 }
1240 int
1241 box3d_VP_lies_in_PL_sector (SPBox3D const *box, Proj::Axis vpdir, int id1, int id2, Box3D::Axis axis) {
1242 Persp3D *persp = box3d_get_perspective(box);
1244 if (!persp3d_VP_is_finite(persp->perspective_impl, vpdir)) {
1245 return 0;
1246 } else {
1247 return box3d_pt_lies_in_PL_sector(box, persp3d_get_VP(persp, vpdir).affine(), id1, id2, axis);
1248 }
1249 }
1251 /* swap the coordinates of corner0 and corner7 along the specified axis */
1252 static void
1253 box3d_swap_coords(SPBox3D *box, Proj::Axis axis, bool smaller = true) {
1254 box->orig_corner0.normalize();
1255 box->orig_corner7.normalize();
1256 if ((box->orig_corner0[axis] < box->orig_corner7[axis]) != smaller) {
1257 double tmp = box->orig_corner0[axis];
1258 box->orig_corner0[axis] = box->orig_corner7[axis];
1259 box->orig_corner7[axis] = tmp;
1260 }
1261 // Should we also swap the coordinates of save_corner0 and save_corner7?
1262 }
1264 /* ensure that the coordinates of corner0 and corner7 are in the correct order (to prevent everted boxes) */
1265 void
1266 box3d_relabel_corners(SPBox3D *box) {
1267 box3d_swap_coords(box, Proj::X, false);
1268 box3d_swap_coords(box, Proj::Y, false);
1269 box3d_swap_coords(box, Proj::Z, true);
1270 }
1272 static void
1273 box3d_check_for_swapped_coords(SPBox3D *box, Proj::Axis axis, bool smaller) {
1274 box->orig_corner0.normalize();
1275 box->orig_corner7.normalize();
1277 if ((box->orig_corner0[axis] < box->orig_corner7[axis]) != smaller) {
1278 box->swapped = (Box3D::Axis) (box->swapped | Proj::toAffine(axis));
1279 } else {
1280 box->swapped = (Box3D::Axis) (box->swapped & ~Proj::toAffine(axis));
1281 }
1282 }
1284 static void
1285 box3d_exchange_coords(SPBox3D *box) {
1286 box->orig_corner0.normalize();
1287 box->orig_corner7.normalize();
1289 for (int i = 0; i < 3; ++i) {
1290 if (box->swapped & Box3D::axes[i]) {
1291 double tmp = box->orig_corner0[i];
1292 box->orig_corner0[i] = box->orig_corner7[i];
1293 box->orig_corner7[i] = tmp;
1294 }
1295 }
1296 }
1298 void
1299 box3d_check_for_swapped_coords(SPBox3D *box) {
1300 box3d_check_for_swapped_coords(box, Proj::X, false);
1301 box3d_check_for_swapped_coords(box, Proj::Y, false);
1302 box3d_check_for_swapped_coords(box, Proj::Z, true);
1304 box3d_exchange_coords(box);
1305 }
1307 static void
1308 box3d_extract_boxes_rec(SPObject *obj, std::list<SPBox3D *> &boxes) {
1309 if (SP_IS_BOX3D(obj)) {
1310 boxes.push_back(SP_BOX3D(obj));
1311 } else if (SP_IS_GROUP(obj)) {
1312 for (SPObject *child = obj->first_child(); child != NULL; child = SP_OBJECT_NEXT(child) ) {
1313 box3d_extract_boxes_rec(child, boxes);
1314 }
1315 }
1316 }
1318 std::list<SPBox3D *>
1319 box3d_extract_boxes(SPObject *obj) {
1320 std::list<SPBox3D *> boxes;
1321 box3d_extract_boxes_rec(obj, boxes);
1322 return boxes;
1323 }
1325 Persp3D *
1326 box3d_get_perspective(SPBox3D const *box) {
1327 return box->persp_ref->getObject();
1328 }
1330 void
1331 box3d_switch_perspectives(SPBox3D *box, Persp3D *old_persp, Persp3D *new_persp, bool recompute_corners) {
1332 if (recompute_corners) {
1333 box->orig_corner0.normalize();
1334 box->orig_corner7.normalize();
1335 double z0 = box->orig_corner0[Proj::Z];
1336 double z7 = box->orig_corner7[Proj::Z];
1337 Geom::Point corner0_screen = box3d_get_corner_screen(box, 0, false);
1338 Geom::Point corner7_screen = box3d_get_corner_screen(box, 7, false);
1340 box->orig_corner0 = new_persp->perspective_impl->tmat.preimage(corner0_screen, z0, Proj::Z);
1341 box->orig_corner7 = new_persp->perspective_impl->tmat.preimage(corner7_screen, z7, Proj::Z);
1342 }
1344 persp3d_remove_box (old_persp, box);
1345 persp3d_add_box (new_persp, box);
1347 //gchar *href = g_strdup_printf("#%s", SP_OBJECT_REPR(new_persp)->attribute("id"));
1348 Glib::ustring href = "#";
1349 href += new_persp->getId();
1350 //SP_OBJECT_REPR(box)->setAttribute("inkscape:perspectiveID", href.c_str());
1351 static_cast<SPObject *>(box)->setAttribute("inkscape:perspectiveID", href.c_str());
1352 //g_free(href);
1353 }
1355 /* Converts the 3D box to an ordinary SPGroup, adds it to the XML tree at the same position as
1356 the original box and deletes the latter */
1357 SPGroup *
1358 box3d_convert_to_group(SPBox3D *box) {
1359 SPDocument *doc = SP_OBJECT_DOCUMENT(box);
1360 Inkscape::XML::Document *xml_doc = sp_document_repr_doc(doc);
1362 // remember position of the box
1363 int pos = static_cast<SPObject *>(box)->getPosition();
1365 // remember important attributes
1366 //Inkscape::XML::Node *repr_source = SP_OBJECT_REPR(box);
1367 gchar const *id = static_cast<SPObject *>(box)->getAttribute("id");
1368 gchar const *style = static_cast<SPObject *>(box)->getAttribute("style");
1369 gchar const *mask = static_cast<SPObject *>(box)->getAttribute("mask");
1370 gchar const *clip_path = static_cast<SPObject *>(box)->getAttribute("clip-path");
1372 // create a new group and add the sides (converted to ordinary paths) as its children
1373 Inkscape::XML::Node *grepr = xml_doc->createElement("svg:g");
1375 Inkscape::XML::Node *repr;
1376 for (SPObject *child = SP_OBJECT(box)->first_child(); child != NULL; child = SP_OBJECT_NEXT(child) ) {
1377 if (SP_IS_BOX3D_SIDE(child)) {
1378 repr = box3d_side_convert_to_path(SP_BOX3D_SIDE(child));
1379 grepr->appendChild(repr);
1380 } else {
1381 g_warning("Non-side item encountered as child of a 3D box.");
1382 }
1383 }
1385 // add the new group to the box's parent and set remembered position
1386 SPObject *parent = SP_OBJECT_PARENT(box);
1387 parent->appendChild(grepr);
1388 grepr->setPosition(pos);
1389 grepr->setAttribute("style", style);
1390 if (mask)
1391 grepr->setAttribute("mask", mask);
1392 if (clip_path)
1393 grepr->setAttribute("clip-path", clip_path);
1395 SP_OBJECT(box)->deleteObject(true);
1397 grepr->setAttribute("id", id);
1399 return SP_GROUP(doc->getObjectByRepr(grepr));
1400 }
1402 static inline void
1403 box3d_push_back_corner_pair(SPBox3D *box, std::list<std::pair<Geom::Point, Geom::Point> > &pts, int c1, int c2) {
1404 pts.push_back(std::make_pair(box3d_get_corner_screen(box, c1, false),
1405 box3d_get_corner_screen(box, c2, false)));
1406 }
1408 void
1409 box3d_convert_to_guides(SPItem *item) {
1410 SPBox3D *box = SP_BOX3D(item);
1411 Inkscape::Preferences *prefs = Inkscape::Preferences::get();
1413 if (!prefs->getBool("/tools/shapes/3dbox/convertguides", true)) {
1414 SP_ITEM(box)->convert_to_guides();
1415 return;
1416 }
1418 std::list<std::pair<Geom::Point, Geom::Point> > pts;
1420 /* perspective lines in X direction */
1421 box3d_push_back_corner_pair(box, pts, 0, 1);
1422 box3d_push_back_corner_pair(box, pts, 2, 3);
1423 box3d_push_back_corner_pair(box, pts, 4, 5);
1424 box3d_push_back_corner_pair(box, pts, 6, 7);
1426 /* perspective lines in Y direction */
1427 box3d_push_back_corner_pair(box, pts, 0, 2);
1428 box3d_push_back_corner_pair(box, pts, 1, 3);
1429 box3d_push_back_corner_pair(box, pts, 4, 6);
1430 box3d_push_back_corner_pair(box, pts, 5, 7);
1432 /* perspective lines in Z direction */
1433 box3d_push_back_corner_pair(box, pts, 0, 4);
1434 box3d_push_back_corner_pair(box, pts, 1, 5);
1435 box3d_push_back_corner_pair(box, pts, 2, 6);
1436 box3d_push_back_corner_pair(box, pts, 3, 7);
1438 sp_guide_pt_pairs_to_guides(inkscape_active_desktop(), pts);
1439 }
1441 /*
1442 Local Variables:
1443 mode:c++
1444 c-file-style:"stroustrup"
1445 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1446 indent-tabs-mode:nil
1447 fill-column:99
1448 End:
1449 */
1450 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :