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 g_print ("No document for the box!!!!\n");
132 return;
133 }
135 box->persp_ref->changedSignal().connect(sigc::bind(sigc::ptr_fun(box3d_ref_changed), box));
137 sp_object_read_attr(object, "inkscape:perspectiveID");
138 sp_object_read_attr(object, "inkscape:corner0");
139 sp_object_read_attr(object, "inkscape:corner7");
140 }
142 /**
143 * Virtual release of SPBox3D members before destruction.
144 */
145 static void
146 box3d_release(SPObject *object)
147 {
148 SPBox3D *box = (SPBox3D *) object;
150 if (box->persp_href) {
151 g_free(box->persp_href);
152 }
153 if (box->persp_ref) {
154 box->persp_ref->detach();
155 delete box->persp_ref;
156 box->persp_ref = NULL;
157 }
159 //persp3d_remove_box (box3d_get_perspective(box), box);
161 if (((SPObjectClass *) parent_class)->release)
162 ((SPObjectClass *) parent_class)->release(object);
163 }
165 static void
166 box3d_set(SPObject *object, unsigned int key, const gchar *value)
167 {
168 SPBox3D *box = SP_BOX3D(object);
170 switch (key) {
171 case SP_ATTR_INKSCAPE_BOX3D_PERSPECTIVE_ID:
172 if ( value && box->persp_href && ( strcmp(value, box->persp_href) == 0 ) ) {
173 /* No change, do nothing. */
174 } else {
175 if (box->persp_href) {
176 g_free(box->persp_href);
177 box->persp_href = NULL;
178 }
179 if (value) {
180 box->persp_href = g_strdup(value);
182 // Now do the attaching, which emits the changed signal.
183 try {
184 box->persp_ref->attach(Inkscape::URI(value));
185 } catch (Inkscape::BadURIException &e) {
186 g_warning("%s", e.what());
187 box->persp_ref->detach();
188 }
189 } else {
190 // Detach, which emits the changed signal.
191 box->persp_ref->detach();
192 }
193 }
195 // FIXME: Is the following update doubled by some call in either persp3d.cpp or vanishing_point_new.cpp?
196 box3d_position_set(box);
197 break;
198 case SP_ATTR_INKSCAPE_BOX3D_CORNER0:
199 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
200 box->orig_corner0 = Proj::Pt3(value);
201 box->save_corner0 = box->orig_corner0;
202 box3d_position_set(box);
203 }
204 break;
205 case SP_ATTR_INKSCAPE_BOX3D_CORNER7:
206 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
207 box->orig_corner7 = Proj::Pt3(value);
208 box->save_corner7 = box->orig_corner7;
209 box3d_position_set(box);
210 }
211 break;
212 default:
213 if (((SPObjectClass *) (parent_class))->set) {
214 ((SPObjectClass *) (parent_class))->set(object, key, value);
215 }
216 break;
217 }
218 }
220 /**
221 * Gets called when (re)attached to another perspective.
222 */
223 static void
224 box3d_ref_changed(SPObject *old_ref, SPObject *ref, SPBox3D *box)
225 {
226 if (old_ref) {
227 sp_signal_disconnect_by_data(old_ref, box);
228 persp3d_remove_box (SP_PERSP3D(old_ref), box);
229 /* Note: This sometimes leads to attempts to remove boxes twice from the list of selected/transformed
230 boxes in a perspectives, but this should be uncritical. */
231 persp3d_remove_box_transform (SP_PERSP3D(old_ref), box);
232 }
233 if ( SP_IS_PERSP3D(ref) && ref != box ) // FIXME: Comparisons sane?
234 {
235 persp3d_add_box (SP_PERSP3D(ref), box);
236 /* Note: This sometimes leads to attempts to add boxes twice to the list of selected/transformed
237 boxes in a perspectives, but this should be uncritical. */
238 persp3d_add_box_transform (SP_PERSP3D(ref), box);
239 }
240 }
242 static void
243 box3d_update(SPObject *object, SPCtx *ctx, guint flags)
244 {
245 if (flags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG | SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
247 /* FIXME?: Perhaps the display updates of box sides should be instantiated from here, but this
248 causes evil update loops so it's all done from box3d_position_set, which is called from
249 various other places (like the handlers in object-edit.cpp, vanishing-point.cpp, etc. */
251 }
253 // Invoke parent method
254 if (((SPObjectClass *) (parent_class))->update)
255 ((SPObjectClass *) (parent_class))->update(object, ctx, flags);
256 }
259 static Inkscape::XML::Node *box3d_write(SPObject *object, Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags)
260 {
261 SPBox3D *box = SP_BOX3D(object);
263 if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
264 // this is where we end up when saving as plain SVG (also in other circumstances?)
265 // thus we don' set "sodipodi:type" so that the box is only saved as an ordinary svg:g
266 repr = xml_doc->createElement("svg:g");
267 }
269 if (flags & SP_OBJECT_WRITE_EXT) {
271 if (box->persp_href) {
272 repr->setAttribute("inkscape:perspectiveID", box->persp_href);
273 } else {
274 /* box is not yet linked to a perspective; use the document's current perspective */
275 SPDocument *doc = SP_OBJECT_DOCUMENT(object);
276 if (box->persp_ref->getURI()) {
277 gchar *uri_string = box->persp_ref->getURI()->toString();
278 repr->setAttribute("inkscape:perspectiveID", uri_string);
279 g_free(uri_string);
280 } else {
281 Inkscape::XML::Node *persp_repr = SP_OBJECT_REPR(doc->current_persp3d);
282 const gchar *persp_id = persp_repr->attribute("id");
283 gchar *href = g_strdup_printf("#%s", persp_id);
284 repr->setAttribute("inkscape:perspectiveID", href);
285 g_free(href);
286 }
287 }
289 gchar *coordstr0 = box->orig_corner0.coord_string();
290 gchar *coordstr7 = box->orig_corner7.coord_string();
291 repr->setAttribute("inkscape:corner0", coordstr0);
292 repr->setAttribute("inkscape:corner7", coordstr7);
293 g_free(coordstr0);
294 g_free(coordstr7);
296 box->orig_corner0.normalize();
297 box->orig_corner7.normalize();
299 box->save_corner0 = box->orig_corner0;
300 box->save_corner7 = box->orig_corner7;
301 }
303 if (((SPObjectClass *) (parent_class))->write) {
304 ((SPObjectClass *) (parent_class))->write(object, xml_doc, repr, flags);
305 }
307 return repr;
308 }
310 static gchar *
311 box3d_description(SPItem *item)
312 {
313 g_return_val_if_fail(SP_IS_BOX3D(item), NULL);
315 return g_strdup(_("<b>3D Box</b>"));
316 }
318 void
319 box3d_position_set (SPBox3D *box)
320 {
321 /* This draws the curve and calls requestDisplayUpdate() for each side (the latter is done in
322 box3d_side_position_set() to avoid update conflicts with the parent box) */
323 for (SPObject *child = sp_object_first_child(SP_OBJECT (box)); child != NULL; child = SP_OBJECT_NEXT(child) ) {
324 if (SP_IS_BOX3D_SIDE(child))
325 box3d_side_position_set(SP_BOX3D_SIDE(child));
326 }
327 }
329 static Geom::Matrix
330 box3d_set_transform(SPItem *item, Geom::Matrix const &xform)
331 {
332 SPBox3D *box = SP_BOX3D(item);
334 /* check whether we need to unlink any boxes from their perspectives */
335 Persp3D *persp = box3d_get_perspective(box);
336 Persp3D *transf_persp;
338 if (sp_desktop_document(inkscape_active_desktop()) == SP_OBJECT_DOCUMENT(item) &&
339 !persp3d_has_all_boxes_in_selection (persp)) {
340 std::list<SPBox3D *> selboxes = sp_desktop_selection(inkscape_active_desktop())->box3DList();
342 /* create a new perspective as a copy of the current one and link the selected boxes to it */
343 transf_persp = persp3d_create_xml_element (SP_OBJECT_DOCUMENT(persp), persp);
345 for (std::list<SPBox3D *>::iterator b = selboxes.begin(); b != selboxes.end(); ++b) {
346 box3d_switch_perspectives(*b, persp, transf_persp);
347 }
348 } else {
349 transf_persp = persp;
350 }
352 /* only transform the perspective once, even if it has several selected boxes */
353 if(!persp3d_was_transformed (transf_persp)) {
354 /* concatenate the affine transformation with the perspective mapping; this
355 function also triggers repr updates of boxes and the perspective itself */
356 persp3d_apply_affine_transformation(transf_persp, xform);
357 }
359 box3d_mark_transformed(box);
361 if (persp3d_all_transformed(transf_persp)) {
362 /* all boxes were transformed; make perspective sensitive for further transformations */
363 persp3d_unset_transforms(transf_persp);
364 }
366 Geom::Matrix ret(Geom::Matrix(xform).without_translation());
367 gdouble const sw = hypot(ret[0], ret[1]);
368 gdouble const sh = hypot(ret[2], ret[3]);
370 for (SPObject *child = sp_object_first_child(box); child != NULL; child = SP_OBJECT_NEXT(child)) {
371 if (SP_IS_ITEM(child)) {
372 SPItem *childitem = SP_ITEM(child);
374 // Adjust stroke width
375 sp_item_adjust_stroke(childitem, sqrt(fabs(sw * sh)));
377 // Adjust pattern fill
378 sp_item_adjust_pattern(childitem, xform);
380 // Adjust gradient fill
381 sp_item_adjust_gradient(childitem, xform);
383 // Adjust LPE
384 sp_item_adjust_livepatheffect(childitem, xform);
385 }
386 }
388 return Geom::identity();
389 }
391 Proj::Pt3
392 box3d_get_proj_corner (guint id, Proj::Pt3 const &c0, Proj::Pt3 const &c7) {
393 return Proj::Pt3 ((id & Box3D::X) ? c7[Proj::X] : c0[Proj::X],
394 (id & Box3D::Y) ? c7[Proj::Y] : c0[Proj::Y],
395 (id & Box3D::Z) ? c7[Proj::Z] : c0[Proj::Z],
396 1.0);
397 }
399 Proj::Pt3
400 box3d_get_proj_corner (SPBox3D const *box, guint id) {
401 return Proj::Pt3 ((id & Box3D::X) ? box->orig_corner7[Proj::X] : box->orig_corner0[Proj::X],
402 (id & Box3D::Y) ? box->orig_corner7[Proj::Y] : box->orig_corner0[Proj::Y],
403 (id & Box3D::Z) ? box->orig_corner7[Proj::Z] : box->orig_corner0[Proj::Z],
404 1.0);
405 }
407 Geom::Point
408 box3d_get_corner_screen (SPBox3D const *box, guint id, bool item_coords) {
409 Proj::Pt3 proj_corner (box3d_get_proj_corner (box, id));
410 if (!box3d_get_perspective(box)) {
411 return Geom::Point (NR_HUGE, NR_HUGE);
412 }
413 Geom::Matrix const i2d (sp_item_i2d_affine (SP_ITEM(box)));
414 if (item_coords) {
415 return box3d_get_perspective(box)->tmat.image(proj_corner).affine() * i2d.inverse();
416 } else {
417 return box3d_get_perspective(box)->tmat.image(proj_corner).affine();
418 }
419 }
421 Proj::Pt3
422 box3d_get_proj_center (SPBox3D *box) {
423 box->orig_corner0.normalize();
424 box->orig_corner7.normalize();
425 return Proj::Pt3 ((box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2,
426 (box->orig_corner0[Proj::Y] + box->orig_corner7[Proj::Y]) / 2,
427 (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2,
428 1.0);
429 }
431 Geom::Point
432 box3d_get_center_screen (SPBox3D *box) {
433 Proj::Pt3 proj_center (box3d_get_proj_center (box));
434 if (!box3d_get_perspective(box)) {
435 return Geom::Point (NR_HUGE, NR_HUGE);
436 }
437 Geom::Matrix const i2d (sp_item_i2d_affine (SP_ITEM(box)));
438 return box3d_get_perspective(box)->tmat.image(proj_center).affine() * i2d.inverse();
439 }
441 /*
442 * To keep the snappoint from jumping randomly between the two lines when the mouse pointer is close to
443 * their intersection, we remember the last snapped line and keep snapping to this specific line as long
444 * as the distance from the intersection to the mouse pointer is less than remember_snap_threshold.
445 */
447 // Should we make the threshold settable in the preferences?
448 static double remember_snap_threshold = 30;
449 static guint remember_snap_index = 0;
451 static Proj::Pt3
452 box3d_snap (SPBox3D *box, int id, Proj::Pt3 const &pt_proj, Proj::Pt3 const &start_pt) {
453 double z_coord = start_pt[Proj::Z];
454 double diff_x = box->save_corner7[Proj::X] - box->save_corner0[Proj::X];
455 double diff_y = box->save_corner7[Proj::Y] - box->save_corner0[Proj::Y];
456 double x_coord = start_pt[Proj::X];
457 double y_coord = start_pt[Proj::Y];
458 Proj::Pt3 A_proj (x_coord, y_coord, z_coord, 1.0);
459 Proj::Pt3 B_proj (x_coord + diff_x, y_coord, z_coord, 1.0);
460 Proj::Pt3 C_proj (x_coord + diff_x, y_coord + diff_y, z_coord, 1.0);
461 Proj::Pt3 D_proj (x_coord, y_coord + diff_y, z_coord, 1.0);
462 Proj::Pt3 E_proj (x_coord - diff_x, y_coord + diff_y, z_coord, 1.0);
464 Persp3D *persp = box3d_get_perspective(box);
465 Geom::Point A = persp->tmat.image(A_proj).affine();
466 Geom::Point B = persp->tmat.image(B_proj).affine();
467 Geom::Point C = persp->tmat.image(C_proj).affine();
468 Geom::Point D = persp->tmat.image(D_proj).affine();
469 Geom::Point E = persp->tmat.image(E_proj).affine();
470 Geom::Point pt = persp->tmat.image(pt_proj).affine();
472 // TODO: Replace these lines between corners with lines from a corner to a vanishing point
473 // (this might help to prevent rounding errors if the box is small)
474 Box3D::Line pl1(A, B);
475 Box3D::Line pl2(A, D);
476 Box3D::Line diag1(A, (id == -1 || (!(id & Box3D::X) == !(id & Box3D::Y))) ? C : E);
477 Box3D::Line diag2(A, E); // diag2 is only taken into account if id equals -1, i.e., if we are snapping the center
479 int num_snap_lines = (id != -1) ? 3 : 4;
480 Geom::Point snap_pts[num_snap_lines];
482 snap_pts[0] = pl1.closest_to (pt);
483 snap_pts[1] = pl2.closest_to (pt);
484 snap_pts[2] = diag1.closest_to (pt);
485 if (id == -1) {
486 snap_pts[3] = diag2.closest_to (pt);
487 }
489 gdouble const zoom = inkscape_active_desktop()->current_zoom();
491 // determine the distances to all potential snapping points
492 double snap_dists[num_snap_lines];
493 for (int i = 0; i < num_snap_lines; ++i) {
494 snap_dists[i] = Geom::L2 (snap_pts[i] - pt) * zoom;
495 }
497 // while we are within a given tolerance of the starting point,
498 // keep snapping to the same point to avoid jumping
499 bool within_tolerance = true;
500 for (int i = 0; i < num_snap_lines; ++i) {
501 if (snap_dists[i] > remember_snap_threshold) {
502 within_tolerance = false;
503 break;
504 }
505 }
507 // find the closest snapping point
508 int snap_index = -1;
509 double snap_dist = NR_HUGE;
510 for (int i = 0; i < num_snap_lines; ++i) {
511 if (snap_dists[i] < snap_dist) {
512 snap_index = i;
513 snap_dist = snap_dists[i];
514 }
515 }
517 // snap to the closest point (or the previously remembered one
518 // if we are within tolerance of the starting point)
519 Geom::Point result;
520 if (within_tolerance) {
521 result = snap_pts[remember_snap_index];
522 } else {
523 remember_snap_index = snap_index;
524 result = snap_pts[snap_index];
525 }
526 return box3d_get_perspective(box)->tmat.preimage (result, z_coord, Proj::Z);
527 }
529 void
530 box3d_set_corner (SPBox3D *box, const guint id, Geom::Point const &new_pos, const Box3D::Axis movement, bool constrained) {
531 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
533 box->orig_corner0.normalize();
534 box->orig_corner7.normalize();
536 /* update corners 0 and 7 according to which handle was moved and to the axes of movement */
537 if (!(movement & Box3D::Z)) {
538 Proj::Pt3 pt_proj (box3d_get_perspective(box)->tmat.preimage (new_pos, (id < 4) ? box->orig_corner0[Proj::Z] :
539 box->orig_corner7[Proj::Z], Proj::Z));
540 if (constrained) {
541 pt_proj = box3d_snap (box, id, pt_proj, box3d_get_proj_corner (id, box->save_corner0, box->save_corner7));
542 }
544 // normalizing pt_proj is essential because we want to mingle affine coordinates
545 pt_proj.normalize();
546 box->orig_corner0 = Proj::Pt3 ((id & Box3D::X) ? box->save_corner0[Proj::X] : pt_proj[Proj::X],
547 (id & Box3D::Y) ? box->save_corner0[Proj::Y] : pt_proj[Proj::Y],
548 box->save_corner0[Proj::Z],
549 1.0);
550 box->orig_corner7 = Proj::Pt3 ((id & Box3D::X) ? pt_proj[Proj::X] : box->save_corner7[Proj::X],
551 (id & Box3D::Y) ? pt_proj[Proj::Y] : box->save_corner7[Proj::Y],
552 box->save_corner7[Proj::Z],
553 1.0);
554 } else {
555 Persp3D *persp = box3d_get_perspective(box);
556 Box3D::PerspectiveLine pl(persp->tmat.image(
557 box3d_get_proj_corner (id, box->save_corner0, box->save_corner7)).affine(),
558 Proj::Z, persp);
559 Geom::Point new_pos_snapped(pl.closest_to(new_pos));
560 Proj::Pt3 pt_proj (persp->tmat.preimage (new_pos_snapped,
561 box3d_get_proj_corner (box, id)[(movement & Box3D::Y) ? Proj::X : Proj::Y],
562 (movement & Box3D::Y) ? Proj::X : Proj::Y));
563 bool corner0_move_x = !(id & Box3D::X) && (movement & Box3D::X);
564 bool corner0_move_y = !(id & Box3D::Y) && (movement & Box3D::Y);
565 bool corner7_move_x = (id & Box3D::X) && (movement & Box3D::X);
566 bool corner7_move_y = (id & Box3D::Y) && (movement & Box3D::Y);
567 // normalizing pt_proj is essential because we want to mingle affine coordinates
568 pt_proj.normalize();
569 box->orig_corner0 = Proj::Pt3 (corner0_move_x ? pt_proj[Proj::X] : box->orig_corner0[Proj::X],
570 corner0_move_y ? pt_proj[Proj::Y] : box->orig_corner0[Proj::Y],
571 (id & Box3D::Z) ? box->orig_corner0[Proj::Z] : pt_proj[Proj::Z],
572 1.0);
573 box->orig_corner7 = Proj::Pt3 (corner7_move_x ? pt_proj[Proj::X] : box->orig_corner7[Proj::X],
574 corner7_move_y ? pt_proj[Proj::Y] : box->orig_corner7[Proj::Y],
575 (id & Box3D::Z) ? pt_proj[Proj::Z] : box->orig_corner7[Proj::Z],
576 1.0);
577 }
578 // FIXME: Should we update the box here? If so, how?
579 }
581 void box3d_set_center (SPBox3D *box, Geom::Point const &new_pos, Geom::Point const &old_pos, const Box3D::Axis movement, bool constrained) {
582 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
584 box->orig_corner0.normalize();
585 box->orig_corner7.normalize();
587 Persp3D *persp = box3d_get_perspective(box);
588 if (!(movement & Box3D::Z)) {
589 double coord = (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2;
590 double radx = (box->orig_corner7[Proj::X] - box->orig_corner0[Proj::X]) / 2;
591 double rady = (box->orig_corner7[Proj::Y] - box->orig_corner0[Proj::Y]) / 2;
593 Proj::Pt3 pt_proj (persp->tmat.preimage (new_pos, coord, Proj::Z));
594 if (constrained) {
595 Proj::Pt3 old_pos_proj (persp->tmat.preimage (old_pos, coord, Proj::Z));
596 old_pos_proj.normalize();
597 pt_proj = box3d_snap (box, -1, pt_proj, old_pos_proj);
598 }
599 // normalizing pt_proj is essential because we want to mingle affine coordinates
600 pt_proj.normalize();
601 box->orig_corner0 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] - radx : box->orig_corner0[Proj::X],
602 (movement & Box3D::Y) ? pt_proj[Proj::Y] - rady : box->orig_corner0[Proj::Y],
603 box->orig_corner0[Proj::Z],
604 1.0);
605 box->orig_corner7 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] + radx : box->orig_corner7[Proj::X],
606 (movement & Box3D::Y) ? pt_proj[Proj::Y] + rady : box->orig_corner7[Proj::Y],
607 box->orig_corner7[Proj::Z],
608 1.0);
609 } else {
610 double coord = (box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2;
611 double radz = (box->orig_corner7[Proj::Z] - box->orig_corner0[Proj::Z]) / 2;
613 Box3D::PerspectiveLine pl(old_pos, Proj::Z, persp);
614 Geom::Point new_pos_snapped(pl.closest_to(new_pos));
615 Proj::Pt3 pt_proj (persp->tmat.preimage (new_pos_snapped, coord, Proj::X));
617 /* normalizing pt_proj is essential because we want to mingle affine coordinates */
618 pt_proj.normalize();
619 box->orig_corner0 = Proj::Pt3 (box->orig_corner0[Proj::X],
620 box->orig_corner0[Proj::Y],
621 pt_proj[Proj::Z] - radz,
622 1.0);
623 box->orig_corner7 = Proj::Pt3 (box->orig_corner7[Proj::X],
624 box->orig_corner7[Proj::Y],
625 pt_proj[Proj::Z] + radz,
626 1.0);
627 }
628 }
630 /*
631 * Manipulates corner1 through corner4 to contain the indices of the corners
632 * from which the perspective lines in the direction of 'axis' emerge
633 */
634 void box3d_corners_for_PLs (const SPBox3D * box, Proj::Axis axis,
635 Geom::Point &corner1, Geom::Point &corner2, Geom::Point &corner3, Geom::Point &corner4)
636 {
637 Persp3D *persp = box3d_get_perspective(box);
638 g_return_if_fail (persp);
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->tmat.image(c1).affine();
670 corner2 = persp->tmat.image(c2).affine();
671 corner3 = persp->tmat.image(c3).affine();
672 corner4 = persp->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, 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 = sp_object_first_child(box); side != NULL; side = SP_OBJECT_NEXT(side)) {
1169 if (SP_IS_BOX3D_SIDE(side))
1170 sides[Box3D::face_to_int(sp_repr_get_int_attribute(SP_OBJECT_REPR(side),
1171 "inkscape:box3dsidetype", -1))] = SP_BOX3D_SIDE(side);
1172 }
1173 sides.erase(-1);
1174 return sides;
1175 }
1178 // TODO: Check whether the box is everted in any direction and swap the sides opposite to this direction
1179 void
1180 box3d_set_z_orders (SPBox3D *box) {
1181 // For efficiency reasons, we only set the new z-orders if something really changed
1182 if (box3d_recompute_z_orders (box)) {
1183 std::map<int, Box3DSide *> sides = box3d_get_sides(box);
1184 std::map<int, Box3DSide *>::iterator side;
1185 for (unsigned int i = 0; i < 6; ++i) {
1186 side = sides.find(box->z_orders[i]);
1187 if (side != sides.end()) {
1188 SP_ITEM((*side).second)->lowerToBottom();
1189 }
1190 }
1191 }
1192 }
1194 /*
1195 * Auxiliary function for z-order recomputing:
1196 * Determines whether \a pt lies in the sector formed by the two PLs from the corners with IDs
1197 * \a i21 and \a id2 to the VP in direction \a axis. If the VP is infinite, we say that \a pt
1198 * lies in the sector if it lies between the two (parallel) PLs.
1199 * \ret * 0 if \a pt doesn't lie in the sector
1200 * * 1 if \a pt lies in the sector and either VP is finite of VP is infinite and the direction
1201 * from the edge between the two corners to \a pt points towards the VP
1202 * * -1 otherwise
1203 */
1204 // TODO: Maybe it would be useful to have a similar method for projective points pt because then we
1205 // can use it for VPs and perhaps merge the case distinctions during z-order recomputation.
1206 int
1207 box3d_pt_lies_in_PL_sector (SPBox3D const *box, Geom::Point const &pt, int id1, int id2, Box3D::Axis axis) {
1208 Persp3D *persp = box3d_get_perspective(box);
1210 // the two corners
1211 Geom::Point c1(box3d_get_corner_screen(box, id1, false));
1212 Geom::Point c2(box3d_get_corner_screen(box, id2, false));
1214 int ret = 0;
1215 if (persp3d_VP_is_finite(persp, Box3D::toProj(axis))) {
1216 Geom::Point vp(persp3d_get_VP(persp, Box3D::toProj(axis)).affine());
1217 Geom::Point v1(c1 - vp);
1218 Geom::Point v2(c2 - vp);
1219 Geom::Point w(pt - vp);
1220 ret = static_cast<int>(Box3D::lies_in_sector(v1, v2, w));
1221 } else {
1222 Box3D::PerspectiveLine pl1(c1, Box3D::toProj(axis), persp);
1223 Box3D::PerspectiveLine pl2(c2, Box3D::toProj(axis), persp);
1224 if (pl1.lie_on_same_side(pt, c2) && pl2.lie_on_same_side(pt, c1)) {
1225 // test whether pt lies "towards" or "away from" the VP
1226 Box3D::Line edge(c1,c2);
1227 Geom::Point c3(box3d_get_corner_screen(box, id1 ^ axis, false));
1228 if (edge.lie_on_same_side(pt, c3)) {
1229 ret = 1;
1230 } else {
1231 ret = -1;
1232 }
1233 }
1234 }
1235 return ret;
1236 }
1238 int
1239 box3d_VP_lies_in_PL_sector (SPBox3D const *box, Proj::Axis vpdir, int id1, int id2, Box3D::Axis axis) {
1240 Persp3D *persp = box3d_get_perspective(box);
1242 if (!persp3d_VP_is_finite(persp, vpdir)) {
1243 return 0;
1244 } else {
1245 return box3d_pt_lies_in_PL_sector(box, persp3d_get_VP(persp, vpdir).affine(), id1, id2, axis);
1246 }
1247 }
1249 /* swap the coordinates of corner0 and corner7 along the specified axis */
1250 static void
1251 box3d_swap_coords(SPBox3D *box, Proj::Axis axis, bool smaller = true) {
1252 box->orig_corner0.normalize();
1253 box->orig_corner7.normalize();
1254 if ((box->orig_corner0[axis] < box->orig_corner7[axis]) != smaller) {
1255 double tmp = box->orig_corner0[axis];
1256 box->orig_corner0[axis] = box->orig_corner7[axis];
1257 box->orig_corner7[axis] = tmp;
1258 }
1259 // Should we also swap the coordinates of save_corner0 and save_corner7?
1260 }
1262 /* ensure that the coordinates of corner0 and corner7 are in the correct order (to prevent everted boxes) */
1263 void
1264 box3d_relabel_corners(SPBox3D *box) {
1265 box3d_swap_coords(box, Proj::X, false);
1266 box3d_swap_coords(box, Proj::Y, false);
1267 box3d_swap_coords(box, Proj::Z, true);
1268 }
1270 static void
1271 box3d_check_for_swapped_coords(SPBox3D *box, Proj::Axis axis, bool smaller) {
1272 box->orig_corner0.normalize();
1273 box->orig_corner7.normalize();
1275 if ((box->orig_corner0[axis] < box->orig_corner7[axis]) != smaller) {
1276 box->swapped = (Box3D::Axis) (box->swapped | Proj::toAffine(axis));
1277 } else {
1278 box->swapped = (Box3D::Axis) (box->swapped & ~Proj::toAffine(axis));
1279 }
1280 }
1282 static void
1283 box3d_exchange_coords(SPBox3D *box) {
1284 box->orig_corner0.normalize();
1285 box->orig_corner7.normalize();
1287 for (int i = 0; i < 3; ++i) {
1288 if (box->swapped & Box3D::axes[i]) {
1289 double tmp = box->orig_corner0[i];
1290 box->orig_corner0[i] = box->orig_corner7[i];
1291 box->orig_corner7[i] = tmp;
1292 }
1293 }
1294 }
1296 void
1297 box3d_check_for_swapped_coords(SPBox3D *box) {
1298 box3d_check_for_swapped_coords(box, Proj::X, false);
1299 box3d_check_for_swapped_coords(box, Proj::Y, false);
1300 box3d_check_for_swapped_coords(box, Proj::Z, true);
1302 box3d_exchange_coords(box);
1303 }
1305 void
1306 box3d_add_to_selection(SPBox3D *box) {
1307 Persp3D *persp = box3d_get_perspective(box);
1308 g_return_if_fail(persp);
1309 persp3d_add_box_transform(persp, box);
1310 }
1312 void
1313 box3d_remove_from_selection(SPBox3D *box) {
1314 Persp3D *persp = box3d_get_perspective(box);
1315 if (!persp) {
1316 /* this can happen if a box is deleted through undo and the persp_ref is already detached;
1317 should we rebuild the boxes of each perspective in this case or is it safe to leave it alone? */
1318 return;
1319 }
1320 persp3d_remove_box_transform(persp, box);
1321 }
1323 void
1324 box3d_mark_transformed(SPBox3D *box) {
1325 Persp3D *persp = box3d_get_perspective(box);
1326 g_return_if_fail(persp);
1327 persp3d_set_box_transformed(persp, box, true);
1328 }
1330 static void
1331 box3d_extract_boxes_rec(SPObject *obj, std::list<SPBox3D *> &boxes) {
1332 if (SP_IS_BOX3D(obj)) {
1333 boxes.push_back(SP_BOX3D(obj));
1334 } else if (SP_IS_GROUP(obj)) {
1335 for (SPObject *child = sp_object_first_child(obj); child != NULL; child = SP_OBJECT_NEXT(child) ) {
1336 box3d_extract_boxes_rec(child, boxes);
1337 }
1338 }
1339 }
1341 std::list<SPBox3D *>
1342 box3d_extract_boxes(SPObject *obj) {
1343 std::list<SPBox3D *> boxes;
1344 box3d_extract_boxes_rec(obj, boxes);
1345 return boxes;
1346 }
1348 Persp3D *
1349 box3d_get_perspective(SPBox3D const *box) {
1350 return box->persp_ref->getObject();
1351 }
1353 void
1354 box3d_switch_perspectives(SPBox3D *box, Persp3D *old_persp, Persp3D *new_persp, bool recompute_corners) {
1355 if (recompute_corners) {
1356 box->orig_corner0.normalize();
1357 box->orig_corner7.normalize();
1358 double z0 = box->orig_corner0[Proj::Z];
1359 double z7 = box->orig_corner7[Proj::Z];
1360 Geom::Point corner0_screen = box3d_get_corner_screen(box, 0, false);
1361 Geom::Point corner7_screen = box3d_get_corner_screen(box, 7, false);
1363 box->orig_corner0 = new_persp->tmat.preimage(corner0_screen, z0, Proj::Z);
1364 box->orig_corner7 = new_persp->tmat.preimage(corner7_screen, z7, Proj::Z);
1365 }
1367 persp3d_remove_box (old_persp, box);
1368 persp3d_add_box (new_persp, box);
1370 persp3d_remove_box_transform (old_persp, box);
1371 persp3d_add_box_transform (new_persp, box);
1373 gchar *href = g_strdup_printf("#%s", SP_OBJECT_REPR(new_persp)->attribute("id"));
1374 SP_OBJECT_REPR(box)->setAttribute("inkscape:perspectiveID", href);
1375 g_free(href);
1376 }
1378 /* Converts the 3D box to an ordinary SPGroup, adds it to the XML tree at the same position as
1379 the original box and deletes the latter */
1380 SPGroup *
1381 box3d_convert_to_group(SPBox3D *box) {
1382 SPDocument *doc = SP_OBJECT_DOCUMENT(box);
1383 Inkscape::XML::Document *xml_doc = sp_document_repr_doc(doc);
1385 // remember position of the box
1386 int pos = SP_OBJECT_REPR(box)->position();
1388 // remember important attributes
1389 Inkscape::XML::Node *repr_source = SP_OBJECT_REPR(box);
1390 gchar const *id = repr_source->attribute("id");
1391 gchar const *style = repr_source->attribute("style");
1392 gchar const *mask = repr_source->attribute("mask");
1393 gchar const *clip_path = repr_source->attribute("clip-path");
1395 // create a new group and add the sides (converted to ordinary paths) as its children
1396 Inkscape::XML::Node *grepr = xml_doc->createElement("svg:g");
1398 Inkscape::XML::Node *repr;
1399 for (SPObject *child = sp_object_first_child(SP_OBJECT(box)); child != NULL; child = SP_OBJECT_NEXT(child) ) {
1400 if (SP_IS_BOX3D_SIDE(child)) {
1401 repr = box3d_side_convert_to_path(SP_BOX3D_SIDE(child));
1402 grepr->appendChild(repr);
1403 } else {
1404 g_warning("Non-side item encountered as child of a 3D box.");
1405 }
1406 }
1408 // add the new group to the box's parent and set remembered position
1409 SPObject *parent = SP_OBJECT_PARENT(box);
1410 SP_OBJECT_REPR(parent)->appendChild(grepr);
1411 grepr->setPosition(pos);
1412 grepr->setAttribute("style", style);
1413 if (mask)
1414 grepr->setAttribute("mask", mask);
1415 if (clip_path)
1416 grepr->setAttribute("clip-path", clip_path);
1418 SP_OBJECT(box)->deleteObject(true);
1420 grepr->setAttribute("id", id);
1422 return SP_GROUP(doc->getObjectByRepr(grepr));
1423 }
1425 static inline void
1426 box3d_push_back_corner_pair(SPBox3D *box, std::list<std::pair<Geom::Point, Geom::Point> > &pts, int c1, int c2) {
1427 pts.push_back(std::make_pair(box3d_get_corner_screen(box, c1, false),
1428 box3d_get_corner_screen(box, c2, false)));
1429 }
1431 void
1432 box3d_convert_to_guides(SPItem *item) {
1433 SPBox3D *box = SP_BOX3D(item);
1434 Inkscape::Preferences *prefs = Inkscape::Preferences::get();
1436 if (!prefs->getBool("/tools/shapes/3dbox/convertguides", true)) {
1437 sp_item_convert_to_guides(SP_ITEM(box));
1438 return;
1439 }
1441 std::list<std::pair<Geom::Point, Geom::Point> > pts;
1443 /* perspective lines in X direction */
1444 box3d_push_back_corner_pair(box, pts, 0, 1);
1445 box3d_push_back_corner_pair(box, pts, 2, 3);
1446 box3d_push_back_corner_pair(box, pts, 4, 5);
1447 box3d_push_back_corner_pair(box, pts, 6, 7);
1449 /* perspective lines in Y direction */
1450 box3d_push_back_corner_pair(box, pts, 0, 2);
1451 box3d_push_back_corner_pair(box, pts, 1, 3);
1452 box3d_push_back_corner_pair(box, pts, 4, 6);
1453 box3d_push_back_corner_pair(box, pts, 5, 7);
1455 /* perspective lines in Z direction */
1456 box3d_push_back_corner_pair(box, pts, 0, 4);
1457 box3d_push_back_corner_pair(box, pts, 1, 5);
1458 box3d_push_back_corner_pair(box, pts, 2, 6);
1459 box3d_push_back_corner_pair(box, pts, 3, 7);
1461 sp_guide_pt_pairs_to_guides(inkscape_active_desktop(), pts);
1462 }
1464 /*
1465 Local Variables:
1466 mode:c++
1467 c-file-style:"stroustrup"
1468 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1469 indent-tabs-mode:nil
1470 fill-column:99
1471 End:
1472 */
1473 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :