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/geom.h"
36 #include "desktop.h"
37 #include "macros.h"
39 static void box3d_class_init(SPBox3DClass *klass);
40 static void box3d_init(SPBox3D *box3d);
42 static void box3d_build(SPObject *object, SPDocument *document, Inkscape::XML::Node *repr);
43 static void box3d_release(SPObject *object);
44 static void box3d_set(SPObject *object, unsigned int key, const gchar *value);
45 static void box3d_update(SPObject *object, SPCtx *ctx, guint flags);
46 static Inkscape::XML::Node *box3d_write(SPObject *object, Inkscape::XML::Node *repr, guint flags);
48 static gchar *box3d_description(SPItem *item);
49 static NR::Matrix box3d_set_transform(SPItem *item, NR::Matrix const &xform);
51 static void box3d_ref_changed(SPObject *old_ref, SPObject *ref, SPBox3D *box);
52 static void box3d_ref_modified(SPObject *href, guint flags, SPBox3D *box);
53 //static void box3d_ref_changed(SPObject *old_ref, SPObject *ref, Persp3D *persp);
54 //static void box3d_ref_modified(SPObject *href, guint flags, Persp3D *persp);
56 static SPGroupClass *parent_class;
58 static gint counter = 0;
60 GType
61 box3d_get_type(void)
62 {
63 static GType type = 0;
65 if (!type) {
66 GTypeInfo info = {
67 sizeof(SPBox3DClass),
68 NULL, /* base_init */
69 NULL, /* base_finalize */
70 (GClassInitFunc) box3d_class_init,
71 NULL, /* class_finalize */
72 NULL, /* class_data */
73 sizeof(SPBox3D),
74 16, /* n_preallocs */
75 (GInstanceInitFunc) box3d_init,
76 NULL, /* value_table */
77 };
78 type = g_type_register_static(SP_TYPE_GROUP, "SPBox3D", &info, (GTypeFlags) 0);
79 }
81 return type;
82 }
84 static void
85 box3d_class_init(SPBox3DClass *klass)
86 {
87 SPObjectClass *sp_object_class = (SPObjectClass *) klass;
88 SPItemClass *item_class = (SPItemClass *) klass;
90 parent_class = (SPGroupClass *) g_type_class_ref(SP_TYPE_GROUP);
92 sp_object_class->build = box3d_build;
93 sp_object_class->release = box3d_release;
94 sp_object_class->set = box3d_set;
95 sp_object_class->write = box3d_write;
96 sp_object_class->update = box3d_update;
98 item_class->description = box3d_description;
99 item_class->set_transform = box3d_set_transform;
100 }
102 static void
103 box3d_init(SPBox3D *box)
104 {
105 box->persp_href = NULL;
106 box->persp_ref = new Persp3DReference(SP_OBJECT(box));
107 new (&box->modified_connection) sigc::connection();
108 }
110 static void
111 box3d_build(SPObject *object, SPDocument *document, Inkscape::XML::Node *repr)
112 {
113 if (((SPObjectClass *) (parent_class))->build) {
114 ((SPObjectClass *) (parent_class))->build(object, document, repr);
115 }
117 SPBox3D *box = SP_BOX3D (object);
118 box->my_counter = counter++;
120 /* we initialize the z-orders to zero so that they are updated during dragging */
121 for (int i = 0; i < 6; ++i) {
122 box->z_orders[i] = 0;
123 }
125 // TODO: Create/link to the correct perspective
127 SPDocument *doc = SP_OBJECT_DOCUMENT(box);
128 if (!doc) {
129 g_print ("No document for the box!!!!\n");
130 return;
131 }
132 /**
133 if (!box->persp3d) {
134 g_print ("Box seems to be newly created since no perspective is referenced yet. We reference the current perspective.\n");
135 box->persp3d = doc->current_persp3d;
136 }
137 **/
139 box->persp_ref->changedSignal().connect(sigc::bind(sigc::ptr_fun(box3d_ref_changed), box));
141 sp_object_read_attr(object, "inkscape:perspectiveID");
142 sp_object_read_attr(object, "inkscape:corner0");
143 sp_object_read_attr(object, "inkscape:corner7");
144 }
146 /**
147 * Virtual release of SPBox3D members before destruction.
148 */
149 static void
150 box3d_release(SPObject *object)
151 {
152 SPBox3D *box = (SPBox3D *) object;
154 if (box->persp_href) {
155 g_free(box->persp_href);
156 }
157 if (box->persp_ref) {
158 box->persp_ref->detach();
159 delete box->persp_ref;
160 box->persp_ref = NULL;
161 }
163 box->modified_connection.disconnect();
164 box->modified_connection.~connection();
166 //persp3d_remove_box (box->persp_ref->getObject(), box);
168 if (((SPObjectClass *) parent_class)->release)
169 ((SPObjectClass *) parent_class)->release(object);
170 }
172 static void
173 box3d_set(SPObject *object, unsigned int key, const gchar *value)
174 {
175 SPBox3D *box = SP_BOX3D(object);
177 switch (key) {
178 case SP_ATTR_INKSCAPE_BOX3D_PERSPECTIVE_ID:
179 if ( value && box->persp_href && ( strcmp(value, box->persp_href) == 0 ) ) {
180 /* No change, do nothing. */
181 } else {
182 if (box->persp_href) {
183 g_free(box->persp_href);
184 box->persp_href = NULL;
185 }
186 if (value) {
187 box->persp_href = g_strdup(value);
189 // Now do the attaching, which emits the changed signal.
190 try {
191 box->persp_ref->attach(Inkscape::URI(value));
192 } catch (Inkscape::BadURIException &e) {
193 g_warning("%s", e.what());
194 box->persp_ref->detach();
195 }
196 } else {
197 // Detach, which emits the changed signal.
198 box->persp_ref->detach();
199 // TODO: Clean this up (also w.r.t the surrounding if construct)
200 /***
201 g_print ("No perspective given. Attaching to current perspective instead.\n");
202 g_free(box->persp_href);
203 Inkscape::XML::Node *repr = SP_OBJECT_REPR(inkscape_active_document()->current_persp3d);
204 box->persp_href = g_strdup(repr->attribute("id"));
205 box->persp_ref->attach(Inkscape::URI(box->persp_href));
206 ***/
207 }
208 }
210 // FIXME: Is the following update doubled by some call in either persp3d.cpp or vanishing_point_new.cpp?
211 box3d_position_set(box);
212 break;
213 case SP_ATTR_INKSCAPE_BOX3D_CORNER0:
214 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
215 box->orig_corner0 = Proj::Pt3(value);
216 box->save_corner0 = box->orig_corner0;
217 box3d_position_set(box);
218 }
219 break;
220 case SP_ATTR_INKSCAPE_BOX3D_CORNER7:
221 if (value && strcmp(value, "0 : 0 : 0 : 0")) {
222 box->orig_corner7 = Proj::Pt3(value);
223 box->save_corner7 = box->orig_corner7;
224 box3d_position_set(box);
225 }
226 break;
227 default:
228 if (((SPObjectClass *) (parent_class))->set) {
229 ((SPObjectClass *) (parent_class))->set(object, key, value);
230 }
231 break;
232 }
233 //object->updateRepr(); // This ensures correct update of the box after undo/redo. FIXME: Why is this not present in sp-rect.cpp and similar files?
234 }
236 /**
237 * Gets called when (re)attached to another perspective.
238 */
239 static void
240 box3d_ref_changed(SPObject *old_ref, SPObject *ref, SPBox3D *box)
241 {
242 if (old_ref) {
243 sp_signal_disconnect_by_data(old_ref, box);
244 persp3d_remove_box (SP_PERSP3D(old_ref), box);
245 }
246 if ( SP_IS_PERSP3D(ref) && ref != box ) // FIXME: Comparisons sane?
247 {
248 box->modified_connection.disconnect();
249 box->modified_connection = ref->connectModified(sigc::bind(sigc::ptr_fun(&box3d_ref_modified), box));
250 box3d_ref_modified(ref, 0, box);
251 persp3d_add_box (SP_PERSP3D(ref), box);
252 }
253 }
255 static void
256 box3d_update(SPObject *object, SPCtx *ctx, guint flags)
257 {
258 if (flags & (SP_OBJECT_MODIFIED_FLAG | SP_OBJECT_STYLE_MODIFIED_FLAG | SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
260 /* FIXME?: Perhaps the display updates of box sides should be instantiated from here, but this
261 causes evil update loops so it's all done from box3d_position_set, which is called from
262 various other places (like the handlers in object-edit.cpp, vanishing-point.cpp, etc. */
264 }
266 // Invoke parent method
267 if (((SPObjectClass *) (parent_class))->update)
268 ((SPObjectClass *) (parent_class))->update(object, ctx, flags);
269 }
272 static Inkscape::XML::Node *box3d_write(SPObject *object, Inkscape::XML::Node *repr, guint flags)
273 {
274 SPBox3D *box = SP_BOX3D(object);
276 if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
277 g_print ("Do we ever end up here?\n");
278 Inkscape::XML::Document *xml_doc = sp_document_repr_doc(SP_OBJECT_DOCUMENT(object));
279 repr = xml_doc->createElement("svg:g");
280 repr->setAttribute("sodipodi:type", "inkscape:box3d");
281 }
283 if (flags & SP_OBJECT_WRITE_EXT) {
285 if (box->persp_href) {
286 repr->setAttribute("inkscape:perspectiveID", box->persp_href);
287 } else {
288 /* box is not yet linked to a perspective; use the document's current perspective */
289 SPDocument *doc = inkscape_active_document();
290 if (box->persp_ref->getURI()) {
291 gchar *uri_string = box->persp_ref->getURI()->toString();
292 repr->setAttribute("inkscape:perspectiveID", uri_string);
293 g_free(uri_string);
294 } else if (doc) {
295 //persp3d_add_box (doc->current_persp3d, box);
296 Inkscape::XML::Node *persp_repr = SP_OBJECT_REPR(doc->current_persp3d);
297 const gchar *persp_id = persp_repr->attribute("id");
298 gchar *href = g_strdup_printf("#%s", persp_id);
299 repr->setAttribute("inkscape:perspectiveID", href);
300 g_free(href);
301 } else {
302 g_print ("No active document while creating perspective!!!\n");
303 }
304 }
306 gchar *coordstr0 = box->orig_corner0.coord_string();
307 gchar *coordstr7 = box->orig_corner7.coord_string();
308 repr->setAttribute("inkscape:corner0", coordstr0);
309 repr->setAttribute("inkscape:corner7", coordstr7);
310 g_free(coordstr0);
311 g_free(coordstr7);
313 box->orig_corner0.normalize();
314 box->orig_corner7.normalize();
316 box->save_corner0 = box->orig_corner0;
317 box->save_corner7 = box->orig_corner7;
318 }
320 if (((SPObjectClass *) (parent_class))->write) {
321 ((SPObjectClass *) (parent_class))->write(object, repr, flags);
322 }
324 return repr;
325 }
327 static gchar *
328 box3d_description(SPItem *item)
329 {
330 g_return_val_if_fail(SP_IS_BOX3D(item), NULL);
332 return g_strdup(_("<b>3D Box</b>"));
333 }
335 void
336 box3d_position_set (SPBox3D *box)
337 {
338 /* This draws the curve and calls requestDisplayUpdate() for each side (the latter is done in
339 box3d_side_position_set() to avoid update conflicts with the parent box) */
340 for (SPObject *child = sp_object_first_child(SP_OBJECT (box)); child != NULL; child = SP_OBJECT_NEXT(child) ) {
341 box3d_side_position_set (SP_BOX3D_SIDE (child));
342 }
343 }
345 static NR::Matrix
346 box3d_set_transform(SPItem */*item*/, NR::Matrix const &xform)
347 {
348 /* check whether we need to unlink any boxes from their perspectives */
349 std::set<Persp3D *> p_sel = persp3d_currently_selected_persps(inkscape_active_event_context());
350 Persp3D *persp;
351 Persp3D *transf_persp;
352 for (std::set<Persp3D *>::iterator p = p_sel.begin(); p != p_sel.end(); ++p) {
353 persp = (*p);
354 if (!persp3d_has_all_boxes_in_selection (persp)) {
355 std::list<SPBox3D *> sel = persp3d_selected_boxes (persp);
357 /* create a new perspective as a copy of the current one and link the selected boxes to it */
358 transf_persp = persp3d_create_xml_element (SP_OBJECT_DOCUMENT(persp), persp);
360 for (std::list<SPBox3D *>::iterator b = sel.begin(); b != sel.end(); ++b) {
361 box3d_switch_perspectives(*b, persp, transf_persp);
362 }
363 } else {
364 transf_persp = persp;
365 }
367 /* concatenate the affine transformation with the perspective mapping; this
368 function also triggers repr updates of boxes and the perspective itself */
369 persp3d_apply_affine_transformation(transf_persp, xform);
370 }
372 /***
373 // FIXME: We somehow have to apply the transformation to strokes, patterns, and gradients. How?
374 NR::Matrix ret(NR::transform(xform));
375 gdouble const sw = hypot(ret[0], ret[1]);
376 gdouble const sh = hypot(ret[2], ret[3]);
378 SPItem *sideitem = NULL;
379 for (SPObject *side = sp_object_first_child(box); side != NULL; side = SP_OBJECT_NEXT(side)) {
380 sideitem = SP_ITEM(side);
382 // Adjust stroke width
383 sp_item_adjust_stroke(sideitem, sqrt(fabs(sw * sh)));
385 // Adjust pattern fill
386 sp_item_adjust_pattern(sideitem, xform);
388 // Adjust gradient fill
389 sp_item_adjust_gradient(sideitem, xform);
390 }
391 ***/
393 return NR::identity();
394 }
397 /**
398 * Gets called when persp(?) repr contents change: i.e. parameter change.
399 */
400 static void
401 box3d_ref_modified(SPObject */*href*/, guint /*flags*/, SPBox3D */*box*/)
402 {
403 /***
404 g_print ("FIXME: box3d_ref_modified was called. What should we do?\n");
405 g_print ("Here is at least the the href's id: %s\n", SP_OBJECT_REPR(href)->attribute("id"));
406 g_print (" ... and the box's, too: %s\n", SP_OBJECT_REPR(box)->attribute("id"));
407 ***/
409 }
411 Proj::Pt3
412 box3d_get_proj_corner (guint id, Proj::Pt3 const &c0, Proj::Pt3 const &c7) {
413 return Proj::Pt3 ((id & Box3D::X) ? c7[Proj::X] : c0[Proj::X],
414 (id & Box3D::Y) ? c7[Proj::Y] : c0[Proj::Y],
415 (id & Box3D::Z) ? c7[Proj::Z] : c0[Proj::Z],
416 1.0);
417 }
419 Proj::Pt3
420 box3d_get_proj_corner (SPBox3D const *box, guint id) {
421 return Proj::Pt3 ((id & Box3D::X) ? box->orig_corner7[Proj::X] : box->orig_corner0[Proj::X],
422 (id & Box3D::Y) ? box->orig_corner7[Proj::Y] : box->orig_corner0[Proj::Y],
423 (id & Box3D::Z) ? box->orig_corner7[Proj::Z] : box->orig_corner0[Proj::Z],
424 1.0);
425 }
427 NR::Point
428 box3d_get_corner_screen (SPBox3D const *box, guint id) {
429 Proj::Pt3 proj_corner (box3d_get_proj_corner (box, id));
430 if (!box->persp_ref->getObject()) {
431 //g_print ("No perspective present in box!! Should we simply use the currently active perspective?\n");
432 return NR::Point (NR_HUGE, NR_HUGE);
433 }
434 return box->persp_ref->getObject()->tmat.image(proj_corner).affine();
435 }
437 Proj::Pt3
438 box3d_get_proj_center (SPBox3D *box) {
439 box->orig_corner0.normalize();
440 box->orig_corner7.normalize();
441 return Proj::Pt3 ((box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2,
442 (box->orig_corner0[Proj::Y] + box->orig_corner7[Proj::Y]) / 2,
443 (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2,
444 1.0);
445 }
447 NR::Point
448 box3d_get_center_screen (SPBox3D *box) {
449 Proj::Pt3 proj_center (box3d_get_proj_center (box));
450 if (!box->persp_ref->getObject()) {
451 //g_print ("No perspective present in box!! Should we simply use the currently active perspective?\n");
452 return NR::Point (NR_HUGE, NR_HUGE);
453 }
454 return box->persp_ref->getObject()->tmat.image(proj_center).affine();
455 }
457 /*
458 * To keep the snappoint from jumping randomly between the two lines when the mouse pointer is close to
459 * their intersection, we remember the last snapped line and keep snapping to this specific line as long
460 * as the distance from the intersection to the mouse pointer is less than remember_snap_threshold.
461 */
463 // Should we make the threshold settable in the preferences?
464 static double remember_snap_threshold = 30;
465 //static guint remember_snap_index = 0;
466 static guint remember_snap_index_center = 0;
468 static Proj::Pt3
469 box3d_snap (SPBox3D *box, int id, Proj::Pt3 const &pt_proj, Proj::Pt3 const &start_pt) {
470 double z_coord = start_pt[Proj::Z];
471 double diff_x = box->save_corner7[Proj::X] - box->save_corner0[Proj::X];
472 double diff_y = box->save_corner7[Proj::Y] - box->save_corner0[Proj::Y];
473 double x_coord = start_pt[Proj::X];
474 double y_coord = start_pt[Proj::Y];
475 Proj::Pt3 A_proj (x_coord, y_coord, z_coord, 1.0);
476 Proj::Pt3 B_proj (x_coord + diff_x, y_coord, z_coord, 1.0);
477 Proj::Pt3 C_proj (x_coord + diff_x, y_coord + diff_y, z_coord, 1.0);
478 Proj::Pt3 D_proj (x_coord, y_coord + diff_y, z_coord, 1.0);
479 Proj::Pt3 E_proj (x_coord - diff_x, y_coord + diff_y, z_coord, 1.0);
481 NR::Point A = box->persp_ref->getObject()->tmat.image(A_proj).affine();
482 NR::Point B = box->persp_ref->getObject()->tmat.image(B_proj).affine();
483 NR::Point C = box->persp_ref->getObject()->tmat.image(C_proj).affine();
484 NR::Point D = box->persp_ref->getObject()->tmat.image(D_proj).affine();
485 NR::Point E = box->persp_ref->getObject()->tmat.image(E_proj).affine();
486 NR::Point pt = box->persp_ref->getObject()->tmat.image(pt_proj).affine();
488 // TODO: Replace these lines between corners with lines from a corner to a vanishing point
489 // (this might help to prevent rounding errors if the box is small)
490 Box3D::Line pl1(A, B);
491 Box3D::Line pl2(A, D);
492 Box3D::Line diag1(A, (id == -1 || (!(id & Box3D::X) == !(id & Box3D::Y))) ? C : E);
493 Box3D::Line diag2(A, E); // diag2 is only taken into account if id equals -1, i.e., if we are snapping the center
495 int num_snap_lines = (id != -1) ? 3 : 4;
496 NR::Point snap_pts[num_snap_lines];
498 snap_pts[0] = pl1.closest_to (pt);
499 snap_pts[1] = pl2.closest_to (pt);
500 snap_pts[2] = diag1.closest_to (pt);
501 if (id == -1) {
502 snap_pts[3] = diag2.closest_to (pt);
503 }
505 gdouble const zoom = inkscape_active_desktop()->current_zoom();
507 // determine the distances to all potential snapping points
508 double snap_dists[num_snap_lines];
509 for (int i = 0; i < num_snap_lines; ++i) {
510 snap_dists[i] = NR::L2 (snap_pts[i] - pt) * zoom;
511 }
513 // while we are within a given tolerance of the starting point,
514 // keep snapping to the same point to avoid jumping
515 bool within_tolerance = true;
516 for (int i = 0; i < num_snap_lines; ++i) {
517 if (snap_dists[i] > remember_snap_threshold) {
518 within_tolerance = false;
519 break;
520 }
521 }
523 // find the closest snapping point
524 int snap_index = -1;
525 double snap_dist = NR_HUGE;
526 for (int i = 0; i < num_snap_lines; ++i) {
527 if (snap_dists[i] < snap_dist) {
528 snap_index = i;
529 snap_dist = snap_dists[i];
530 }
531 }
533 // snap to the closest point (or the previously remembered one
534 // if we are within tolerance of the starting point)
535 NR::Point result;
536 if (within_tolerance) {
537 result = snap_pts[remember_snap_index_center];
538 } else {
539 remember_snap_index_center = snap_index;
540 result = snap_pts[snap_index];
541 }
542 return box->persp_ref->getObject()->tmat.preimage (result, z_coord, Proj::Z);
543 }
545 void
546 box3d_set_corner (SPBox3D *box, const guint id, NR::Point const &new_pos, const Box3D::Axis movement, bool constrained) {
547 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
549 box->orig_corner0.normalize();
550 box->orig_corner7.normalize();
552 /* update corners 0 and 7 according to which handle was moved and to the axes of movement */
553 if (!(movement & Box3D::Z)) {
554 Proj::Pt3 pt_proj (box->persp_ref->getObject()->tmat.preimage (new_pos, (id < 4) ? box->orig_corner0[Proj::Z] :
555 box->orig_corner7[Proj::Z],
556 Proj::Z));
557 if (constrained) {
558 pt_proj = box3d_snap (box, id, pt_proj, box3d_get_proj_corner (id, box->save_corner0, box->save_corner7));
559 }
561 // normalizing pt_proj is essential because we want to mingle affine coordinates
562 pt_proj.normalize();
563 box->orig_corner0 = Proj::Pt3 ((id & Box3D::X) ? box->save_corner0[Proj::X] : pt_proj[Proj::X],
564 (id & Box3D::Y) ? box->save_corner0[Proj::Y] : pt_proj[Proj::Y],
565 box->save_corner0[Proj::Z],
566 1.0);
567 box->orig_corner7 = Proj::Pt3 ((id & Box3D::X) ? pt_proj[Proj::X] : box->save_corner7[Proj::X],
568 (id & Box3D::Y) ? pt_proj[Proj::Y] : box->save_corner7[Proj::Y],
569 box->save_corner7[Proj::Z],
570 1.0);
571 } else {
572 Box3D::PerspectiveLine pl(box->persp_ref->getObject()->tmat.image(
573 box3d_get_proj_corner (id, box->save_corner0, box->save_corner7)).affine(),
574 Proj::Z, box->persp_ref->getObject());
575 NR::Point new_pos_snapped(pl.closest_to(new_pos));
576 Proj::Pt3 pt_proj (box->persp_ref->getObject()->
577 tmat.preimage (new_pos_snapped,
578 box3d_get_proj_corner (box, id)[(movement & Box3D::Y) ? Proj::X : Proj::Y],
579 (movement & Box3D::Y) ? Proj::X : Proj::Y));
580 bool corner0_move_x = !(id & Box3D::X) && (movement & Box3D::X);
581 bool corner0_move_y = !(id & Box3D::Y) && (movement & Box3D::Y);
582 bool corner7_move_x = (id & Box3D::X) && (movement & Box3D::X);
583 bool corner7_move_y = (id & Box3D::Y) && (movement & Box3D::Y);
584 // normalizing pt_proj is essential because we want to mingle affine coordinates
585 pt_proj.normalize();
586 box->orig_corner0 = Proj::Pt3 (corner0_move_x ? pt_proj[Proj::X] : box->orig_corner0[Proj::X],
587 corner0_move_y ? pt_proj[Proj::Y] : box->orig_corner0[Proj::Y],
588 (id & Box3D::Z) ? box->orig_corner0[Proj::Z] : pt_proj[Proj::Z],
589 1.0);
590 box->orig_corner7 = Proj::Pt3 (corner7_move_x ? pt_proj[Proj::X] : box->orig_corner7[Proj::X],
591 corner7_move_y ? pt_proj[Proj::Y] : box->orig_corner7[Proj::Y],
592 (id & Box3D::Z) ? pt_proj[Proj::Z] : box->orig_corner7[Proj::Z],
593 1.0);
594 }
595 // FIXME: Should we update the box here? If so, how?
596 }
598 void box3d_set_center (SPBox3D *box, NR::Point const &new_pos, NR::Point const &old_pos, const Box3D::Axis movement, bool constrained) {
599 g_return_if_fail ((movement != Box3D::NONE) && (movement != Box3D::XYZ));
601 if (!(movement & Box3D::Z)) {
602 double coord = (box->orig_corner0[Proj::Z] + box->orig_corner7[Proj::Z]) / 2;
603 double radx = (box->orig_corner7[Proj::X] - box->orig_corner0[Proj::X]) / 2;
604 double rady = (box->orig_corner7[Proj::Y] - box->orig_corner0[Proj::Y]) / 2;
606 Proj::Pt3 pt_proj (box->persp_ref->getObject()->tmat.preimage (new_pos, coord, Proj::Z));
607 if (constrained) {
608 Proj::Pt3 old_pos_proj (box->persp_ref->getObject()->tmat.preimage (old_pos, coord, Proj::Z));
609 pt_proj = box3d_snap (box, -1, pt_proj, old_pos_proj);
610 }
611 // normalizing pt_proj is essential because we want to mingle affine coordinates
612 pt_proj.normalize();
613 box->orig_corner0 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] - radx : box->orig_corner0[Proj::X],
614 (movement & Box3D::Y) ? pt_proj[Proj::Y] - rady : box->orig_corner0[Proj::Y],
615 box->orig_corner0[Proj::Z],
616 1.0);
617 box->orig_corner7 = Proj::Pt3 ((movement & Box3D::X) ? pt_proj[Proj::X] + radx : box->orig_corner7[Proj::X],
618 (movement & Box3D::Y) ? pt_proj[Proj::Y] + rady : box->orig_corner7[Proj::Y],
619 box->orig_corner7[Proj::Z],
620 1.0);
621 } else {
622 double coord = (box->orig_corner0[Proj::X] + box->orig_corner7[Proj::X]) / 2;
623 double radz = (box->orig_corner7[Proj::Z] - box->orig_corner0[Proj::Z]) / 2;
625 Box3D::PerspectiveLine pl(old_pos, Proj::Z, box->persp_ref->getObject());
626 NR::Point new_pos_snapped(pl.closest_to(new_pos));
627 Proj::Pt3 pt_proj (box->persp_ref->getObject()->tmat.preimage (new_pos_snapped, coord, Proj::X));
629 /* normalizing pt_proj is essential because we want to mingle affine coordinates */
630 pt_proj.normalize();
631 box->orig_corner0 = Proj::Pt3 (box->orig_corner0[Proj::X],
632 box->orig_corner0[Proj::Y],
633 pt_proj[Proj::Z] - radz,
634 1.0);
635 box->orig_corner7 = Proj::Pt3 (box->orig_corner7[Proj::X],
636 box->orig_corner7[Proj::Y],
637 pt_proj[Proj::Z] + radz,
638 1.0);
639 }
640 }
642 /*
643 * Manipulates corner1 through corner4 to contain the indices of the corners
644 * from which the perspective lines in the direction of 'axis' emerge
645 */
646 void box3d_corners_for_PLs (const SPBox3D * box, Proj::Axis axis,
647 NR::Point &corner1, NR::Point &corner2, NR::Point &corner3, NR::Point &corner4)
648 {
649 g_return_if_fail (box->persp_ref->getObject());
650 //box->orig_corner0.normalize();
651 //box->orig_corner7.normalize();
652 double coord = (box->orig_corner0[axis] > box->orig_corner7[axis]) ?
653 box->orig_corner0[axis] :
654 box->orig_corner7[axis];
656 Proj::Pt3 c1, c2, c3, c4;
657 // FIXME: This can certainly be done more elegantly/efficiently than by a case-by-case analysis.
658 switch (axis) {
659 case Proj::X:
660 c1 = Proj::Pt3 (coord, box->orig_corner0[Proj::Y], box->orig_corner0[Proj::Z], 1.0);
661 c2 = Proj::Pt3 (coord, box->orig_corner7[Proj::Y], box->orig_corner0[Proj::Z], 1.0);
662 c3 = Proj::Pt3 (coord, box->orig_corner7[Proj::Y], box->orig_corner7[Proj::Z], 1.0);
663 c4 = Proj::Pt3 (coord, box->orig_corner0[Proj::Y], box->orig_corner7[Proj::Z], 1.0);
664 break;
665 case Proj::Y:
666 c1 = Proj::Pt3 (box->orig_corner0[Proj::X], coord, box->orig_corner0[Proj::Z], 1.0);
667 c2 = Proj::Pt3 (box->orig_corner7[Proj::X], coord, box->orig_corner0[Proj::Z], 1.0);
668 c3 = Proj::Pt3 (box->orig_corner7[Proj::X], coord, box->orig_corner7[Proj::Z], 1.0);
669 c4 = Proj::Pt3 (box->orig_corner0[Proj::X], coord, box->orig_corner7[Proj::Z], 1.0);
670 break;
671 case Proj::Z:
672 c1 = Proj::Pt3 (box->orig_corner7[Proj::X], box->orig_corner7[Proj::Y], coord, 1.0);
673 c2 = Proj::Pt3 (box->orig_corner7[Proj::X], box->orig_corner0[Proj::Y], coord, 1.0);
674 c3 = Proj::Pt3 (box->orig_corner0[Proj::X], box->orig_corner0[Proj::Y], coord, 1.0);
675 c4 = Proj::Pt3 (box->orig_corner0[Proj::X], box->orig_corner7[Proj::Y], coord, 1.0);
676 break;
677 default:
678 return;
679 }
680 corner1 = box->persp_ref->getObject()->tmat.image(c1).affine();
681 corner2 = box->persp_ref->getObject()->tmat.image(c2).affine();
682 corner3 = box->persp_ref->getObject()->tmat.image(c3).affine();
683 corner4 = box->persp_ref->getObject()->tmat.image(c4).affine();
684 }
686 /* Auxiliary function: Checks whether the half-line from A to B crosses the line segment joining C and D */
687 static bool
688 box3d_half_line_crosses_joining_line (Geom::Point const &A, Geom::Point const &B,
689 Geom::Point const &C, Geom::Point const &D) {
690 Geom::Point E; // the point of intersection
691 Geom::Point n0 = (B - A).ccw();
692 double d0 = dot(n0,A);
694 Geom::Point n1 = (D - C).ccw();
695 double d1 = dot(n1,C);
696 Geom::IntersectorKind intersects = Geom::line_intersection(n0, d0, n1, d1, E);
697 if (intersects == Geom::coincident || intersects == Geom::parallel) {
698 return false;
699 }
701 if ((dot(C,n0) < d0) == (dot(D,n0) < d0)) {
702 // C and D lie on the same side of the line AB
703 return false;
704 }
705 if ((dot(A,n1) < d1) != (dot(B,n1) < d1)) {
706 // A and B lie on different sides of the line CD
707 return true;
708 } else if (Geom::distance(E,A) < Geom::distance(E,B)) {
709 // The line CD passes on the "wrong" side of A
710 return false;
711 }
713 // The line CD passes on the "correct" side of A
714 return true;
715 }
717 static bool
718 box3d_XY_axes_are_swapped (SPBox3D *box) {
719 Persp3D *persp = box->persp_ref->getObject();
720 g_return_val_if_fail(persp, false);
721 Box3D::PerspectiveLine l1(box3d_get_corner_screen(box, 3), Proj::X, persp);
722 Box3D::PerspectiveLine l2(box3d_get_corner_screen(box, 3), Proj::Y, persp);
723 NR::Point v1(l1.direction());
724 NR::Point v2(l2.direction());
725 v1.normalize();
726 v2.normalize();
728 return (v1[NR::X]*v2[NR::Y] - v1[NR::Y]*v2[NR::X] > 0);
729 }
731 static inline void
732 box3d_aux_set_z_orders (int z_orders[6], int a, int b, int c, int d, int e, int f) {
733 z_orders[0] = a;
734 z_orders[1] = b;
735 z_orders[2] = c;
736 z_orders[3] = d;
737 z_orders[4] = e;
738 z_orders[5] = f;
739 }
741 static inline void
742 box3d_swap_z_orders (int z_orders[6]) {
743 int tmp;
744 for (int i = 0; i < 3; ++i) {
745 tmp = z_orders[i];
746 z_orders[i] = z_orders[5-i];
747 z_orders[5-i] = tmp;
748 }
749 }
751 /*
752 * In der Standard-Perspektive:
753 * 2 = vorne
754 * 1 = oben
755 * 0 = links
756 * 3 = rechts
757 * 4 = unten
758 * 5 = hinten
759 */
761 /* All VPs infinite */
762 static void
763 box3d_set_new_z_orders_case0 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis) {
764 Persp3D *persp = box->persp_ref->getObject();
765 NR::Point xdir(persp3d_get_infinite_dir(persp, Proj::X));
766 NR::Point ydir(persp3d_get_infinite_dir(persp, Proj::Y));
767 NR::Point zdir(persp3d_get_infinite_dir(persp, Proj::Z));
769 bool swapped = box3d_XY_axes_are_swapped(box);
771 //g_print ("3 infinite VPs; ");
772 switch(central_axis) {
773 case Box3D::X:
774 if (!swapped) {
775 //g_print ("central axis X (case a)");
776 box3d_aux_set_z_orders (z_orders, 2, 0, 4, 1, 3, 5);
777 } else {
778 //g_print ("central axis X (case b)");
779 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 2, 4, 0);
780 }
781 break;
782 case Box3D::Y:
783 if (!swapped) {
784 //g_print ("central axis Y (case a)");
785 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 4, 0, 5);
786 } else {
787 //g_print ("central axis Y (case b)");
788 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
789 }
790 break;
791 case Box3D::Z:
792 if (!swapped) {
793 //g_print ("central axis Z (case a)");
794 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
795 } else {
796 //g_print ("central axis Z (case b)");
797 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 1, 0, 2);
798 }
799 break;
800 case Box3D::NONE:
801 if (!swapped) {
802 //g_print ("central axis NONE (case a)");
803 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
804 } else {
805 //g_print ("central axis NONE (case b)");
806 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 4, 3, 2);
807 }
808 break;
809 default:
810 g_assert_not_reached();
811 break;
812 }
813 /**
814 if (swapped) {
815 g_print ("; swapped");
816 }
817 g_print ("\n");
818 **/
819 }
821 /* Precisely one finite VP */
822 static void
823 box3d_set_new_z_orders_case1 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis, Box3D::Axis fin_axis) {
824 Persp3D *persp = box->persp_ref->getObject();
825 NR::Point vp(persp3d_get_VP(persp, Box3D::toProj(fin_axis)).affine());
827 // note: in some of the case distinctions below we rely upon the fact that oaxis1 and oaxis2 are ordered
828 Box3D::Axis oaxis1 = Box3D::get_remaining_axes(fin_axis).first;
829 Box3D::Axis oaxis2 = Box3D::get_remaining_axes(fin_axis).second;
830 //g_print ("oaxis1 = %s, oaxis2 = %s\n", Box3D::string_from_axes(oaxis1), Box3D::string_from_axes(oaxis2));
831 int inside1 = 0;
832 int inside2 = 0;
833 inside1 = box3d_pt_lies_in_PL_sector (box, vp, 3, 3 ^ oaxis2, oaxis1);
834 inside2 = box3d_pt_lies_in_PL_sector (box, vp, 3, 3 ^ oaxis1, oaxis2);
835 //g_print ("inside1 = %d, inside2 = %d\n", inside1, inside2);
837 bool swapped = box3d_XY_axes_are_swapped(box);
839 //g_print ("2 infinite VPs; ");
840 //g_print ("finite axis: %s; ", Box3D::string_from_axes(fin_axis));
841 switch(central_axis) {
842 case Box3D::X:
843 if (!swapped) {
844 //g_print ("central axis X (case a)");
845 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
846 } else {
847 //if (inside2) {
848 //g_print ("central axis X (case b)");
849 box3d_aux_set_z_orders (z_orders, 5, 3, 1, 0, 2, 4);
850 //} else {
851 //g_print ("central axis X (case c)");
852 //box3d_aux_set_z_orders (z_orders, 5, 3, 1, 2, 0, 4);
853 //}
854 }
855 break;
856 case Box3D::Y:
857 if (inside2 > 0) {
858 //g_print ("central axis Y (case a)");
859 box3d_aux_set_z_orders (z_orders, 1, 2, 3, 0, 5, 4);
860 } else if (inside2 < 0) {
861 //g_print ("central axis Y (case b)");
862 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 4, 0, 5);
863 } else {
864 if (!swapped) {
865 //g_print ("central axis Y (case c1)");
866 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
867 } else {
868 //g_print ("central axis Y (case c2)");
869 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
870 }
871 }
872 break;
873 case Box3D::Z:
874 if (inside2) {
875 if (!swapped) {
876 //g_print ("central axis Z (case a1)");
877 box3d_aux_set_z_orders (z_orders, 2, 1, 3, 0, 4, 5);
878 } else {
879 //g_print ("central axis Z (case a2)");
880 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 0, 1, 2);
881 }
882 } else if (inside1) {
883 if (!swapped) {
884 //g_print ("central axis Z (case b1)");
885 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
886 } else {
887 //g_print ("central axis Z (case b2)");
888 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 1, 0, 2);
889 //box3d_aux_set_z_orders (z_orders, 5, 3, 0, 1, 2, 4);
890 }
891 } else {
892 // "regular" case
893 if (!swapped) {
894 //g_print ("central axis Z (case c1)");
895 box3d_aux_set_z_orders (z_orders, 0, 1, 2, 5, 4, 3);
896 } else {
897 //g_print ("central axis Z (case c2)");
898 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 0, 2, 1);
899 //box3d_aux_set_z_orders (z_orders, 5, 3, 4, 0, 2, 1);
900 }
901 }
902 break;
903 case Box3D::NONE:
904 if (!swapped) {
905 //g_print ("central axis NONE (case a)");
906 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 5, 0, 1);
907 } else {
908 //g_print ("central axis NONE (case b)");
909 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 3, 2, 4);
910 //box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
911 }
912 break;
913 default:
914 g_assert_not_reached();
915 }
916 /**
917 if (swapped) {
918 g_print ("; swapped");
919 }
920 g_print ("\n");
921 **/
922 }
924 /* Precisely 2 finite VPs */
925 static void
926 box3d_set_new_z_orders_case2 (SPBox3D *box, int z_orders[6], Box3D::Axis central_axis, Box3D::Axis /*infinite_axis*/) {
927 Persp3D *persp = box->persp_ref->getObject();
929 NR::Point c3(box3d_get_corner_screen(box, 3));
930 NR::Point xdir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::X));
931 NR::Point ydir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::Y));
932 NR::Point zdir(persp3d_get_PL_dir_from_pt(persp, c3, Proj::Z));
934 bool swapped = box3d_XY_axes_are_swapped(box);
936 int insidexy = box3d_VP_lies_in_PL_sector (box, Proj::X, 3, 3 ^ Box3D::Z, Box3D::Y);
937 int insidexz = box3d_VP_lies_in_PL_sector (box, Proj::X, 3, 3 ^ Box3D::Y, Box3D::Z);
939 int insideyx = box3d_VP_lies_in_PL_sector (box, Proj::Y, 3, 3 ^ Box3D::Z, Box3D::X);
940 int insideyz = box3d_VP_lies_in_PL_sector (box, Proj::Y, 3, 3 ^ Box3D::X, Box3D::Z);
942 int insidezx = box3d_VP_lies_in_PL_sector (box, Proj::Z, 3, 3 ^ Box3D::Y, Box3D::X);
943 int insidezy = box3d_VP_lies_in_PL_sector (box, Proj::Z, 3, 3 ^ Box3D::X, Box3D::Y);
945 //g_print ("Insides: xy = %d, xz = %d, yx = %d, yz = %d, zx = %d, zy = %d\n",
946 // insidexy, insidexz, insideyx, insideyz, insidezx, insidezy);
947 (void)insidexz;
948 (void)insideyx;
949 (void)insidezx;
951 //g_print ("1 infinite VP; ");
952 switch(central_axis) {
953 case Box3D::X:
954 if (!swapped) {
955 if (insidezy == -1) {
956 //g_print ("central axis X (case a1)");
957 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
958 } else if (insidexy == 1) {
959 //g_print ("central axis X (case a2)");
960 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 5, 1, 3);
961 } else {
962 //g_print ("central axis X (case a3)");
963 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 1, 3, 5);
964 }
965 } else {
966 if (insideyz == -1) {
967 //g_print ("central axis X (case b1)");
968 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 0, 2, 4);
969 } else {
970 if (!swapped) {
971 //g_print ("central axis X (case b2)");
972 box3d_aux_set_z_orders (z_orders, 3, 1, 5, 2, 4, 0);
973 } else {
974 //g_print ("central axis X (case b3)");
975 box3d_aux_set_z_orders (z_orders, 1, 3, 5, 0, 2, 4);
976 }
977 }
978 }
979 break;
980 case Box3D::Y:
981 if (!swapped) {
982 if (insideyz == 1) {
983 //g_print ("central axis Y (case a1)");
984 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 0, 5, 4);
985 } else {
986 //g_print ("central axis Y (case a2)");
987 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
988 }
989 } else {
990 //g_print ("central axis Y (case b)");
991 box3d_aux_set_z_orders (z_orders, 5, 0, 4, 1, 3, 2);
992 }
993 break;
994 case Box3D::Z:
995 if (!swapped) {
996 if (insidezy == 1) {
997 //g_print ("central axis Z (case a1)");
998 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 4, 3, 5);
999 } else if (insidexy == -1) {
1000 //g_print ("central axis Z (case a2)");
1001 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 5, 4, 3);
1002 } else {
1003 //g_print ("central axis Z (case a3)");
1004 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 5, 3, 4);
1005 }
1006 } else {
1007 //g_print ("central axis Z (case b)");
1008 box3d_aux_set_z_orders (z_orders, 5, 3, 4, 1, 0, 2);
1009 }
1010 break;
1011 case Box3D::NONE:
1012 if (!swapped) {
1013 //g_print ("central axis NONE (case a)");
1014 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
1015 } else {
1016 //g_print ("central axis NONE (case b)");
1017 box3d_aux_set_z_orders (z_orders, 5, 0, 1, 4, 3, 2);
1018 }
1019 break;
1020 default:
1021 g_assert_not_reached();
1022 break;
1023 }
1024 /**
1025 if (swapped) {
1026 g_print ("; swapped");
1027 }
1028 g_print ("\n");
1029 **/
1030 }
1032 /*
1033 * It can happen that during dragging the box is everted.
1034 * In this case the opposite sides in this direction need to be swapped
1035 */
1036 static Box3D::Axis
1037 box3d_everted_directions (SPBox3D *box) {
1038 Box3D::Axis ev = Box3D::NONE;
1040 box->orig_corner0.normalize();
1041 box->orig_corner7.normalize();
1043 if (box->orig_corner0[Proj::X] < box->orig_corner7[Proj::X])
1044 ev = (Box3D::Axis) (ev ^ Box3D::X);
1045 if (box->orig_corner0[Proj::Y] < box->orig_corner7[Proj::Y])
1046 ev = (Box3D::Axis) (ev ^ Box3D::Y);
1047 if (box->orig_corner0[Proj::Z] > box->orig_corner7[Proj::Z]) // FIXME: Remove the need to distinguish signs among the cases
1048 ev = (Box3D::Axis) (ev ^ Box3D::Z);
1050 return ev;
1051 }
1053 static void
1054 box3d_swap_sides(int z_orders[6], Box3D::Axis axis) {
1055 int pos1 = -1;
1056 int pos2 = -1;
1058 for (int i = 0; i < 6; ++i) {
1059 if (!(Box3D::int_to_face(z_orders[i]) & axis)) {
1060 if (pos1 == -1) {
1061 pos1 = i;
1062 } else {
1063 pos2 = i;
1064 break;
1065 }
1066 }
1067 }
1069 int tmp = z_orders[pos1];
1070 z_orders[pos1] = z_orders[pos2];
1071 z_orders[pos2] = tmp;
1072 }
1075 bool
1076 box3d_recompute_z_orders (SPBox3D *box) {
1077 Persp3D *persp = box->persp_ref->getObject();
1079 //g_return_val_if_fail(persp, false);
1080 if (!persp)
1081 return false;
1083 int z_orders[6];
1085 NR::Point c3(box3d_get_corner_screen(box, 3));
1087 // determine directions from corner3 to the VPs
1088 int num_finite = 0;
1089 Box3D::Axis axis_finite = Box3D::NONE;
1090 Box3D::Axis axis_infinite = Box3D::NONE;
1091 NR::Point dirs[3];
1092 for (int i = 0; i < 3; ++i) {
1093 dirs[i] = persp3d_get_PL_dir_from_pt(persp, c3, Box3D::toProj(Box3D::axes[i]));
1094 if (persp3d_VP_is_finite(persp, Proj::axes[i])) {
1095 num_finite++;
1096 axis_finite = Box3D::axes[i];
1097 } else {
1098 axis_infinite = Box3D::axes[i];
1099 }
1100 }
1102 // determine the "central" axis (if there is one)
1103 Box3D::Axis central_axis = Box3D::NONE;
1104 if(Box3D::lies_in_sector(dirs[0], dirs[1], dirs[2])) {
1105 central_axis = Box3D::Z;
1106 } else if(Box3D::lies_in_sector(dirs[1], dirs[2], dirs[0])) {
1107 central_axis = Box3D::X;
1108 } else if(Box3D::lies_in_sector(dirs[2], dirs[0], dirs[1])) {
1109 central_axis = Box3D::Y;
1110 }
1112 switch (num_finite) {
1113 case 0:
1114 // TODO: Remark: In this case (and maybe one of the others, too) the z-orders for all boxes
1115 // coincide, hence only need to be computed once in a more central location.
1116 box3d_set_new_z_orders_case0(box, z_orders, central_axis);
1117 break;
1118 case 1:
1119 box3d_set_new_z_orders_case1(box, z_orders, central_axis, axis_finite);
1120 break;
1121 case 2:
1122 case 3:
1123 box3d_set_new_z_orders_case2(box, z_orders, central_axis, axis_infinite);
1124 break;
1125 default:
1126 /*
1127 * For each VP F, check wether the half-line from the corner3 to F crosses the line segment
1128 * joining the other two VPs. If this is the case, it determines the "central" corner from
1129 * which the visible sides can be deduced. Otherwise, corner3 is the central corner.
1130 */
1131 // FIXME: We should eliminate the use of NR::Point altogether
1132 Box3D::Axis central_axis = Box3D::NONE;
1133 NR::Point vp_x = persp3d_get_VP(persp, Proj::X).affine();
1134 NR::Point vp_y = persp3d_get_VP(persp, Proj::Y).affine();
1135 NR::Point vp_z = persp3d_get_VP(persp, Proj::Z).affine();
1136 Geom::Point vpx(vp_x[NR::X], vp_x[NR::Y]);
1137 Geom::Point vpy(vp_y[NR::X], vp_y[NR::Y]);
1138 Geom::Point vpz(vp_z[NR::X], vp_z[NR::Y]);
1140 NR::Point c3 = box3d_get_corner_screen(box, 3);
1141 Geom::Point corner3(c3[NR::X], c3[NR::Y]);
1143 if (box3d_half_line_crosses_joining_line (corner3, vpx, vpy, vpz)) {
1144 central_axis = Box3D::X;
1145 } else if (box3d_half_line_crosses_joining_line (corner3, vpy, vpz, vpx)) {
1146 central_axis = Box3D::Y;
1147 } else if (box3d_half_line_crosses_joining_line (corner3, vpz, vpx, vpy)) {
1148 central_axis = Box3D::Z;
1149 }
1150 //g_print ("Crossing: %s\n", Box3D::string_from_axes(central_axis));
1152 unsigned int central_corner = 3 ^ central_axis;
1153 if (central_axis == Box3D::Z) {
1154 central_corner = central_corner ^ Box3D::XYZ;
1155 }
1156 if (box3d_XY_axes_are_swapped(box)) {
1157 //g_print ("Axes X and Y are swapped\n");
1158 central_corner = central_corner ^ Box3D::XYZ;
1159 }
1161 NR::Point c1(box3d_get_corner_screen(box, 1));
1162 NR::Point c2(box3d_get_corner_screen(box, 2));
1163 NR::Point c7(box3d_get_corner_screen(box, 7));
1165 Geom::Point corner1(c1[NR::X], c1[NR::Y]);
1166 Geom::Point corner2(c2[NR::X], c2[NR::Y]);
1167 Geom::Point corner7(c7[NR::X], c7[NR::Y]);
1168 // FIXME: At present we don't use the information about central_corner computed above.
1169 switch (central_axis) {
1170 case Box3D::Y:
1171 if (!box3d_half_line_crosses_joining_line(vpz, vpy, corner3, corner2)) {
1172 box3d_aux_set_z_orders (z_orders, 2, 3, 1, 5, 0, 4);
1173 } else {
1174 // degenerate case
1175 //g_print ("Degenerate case #1\n");
1176 box3d_aux_set_z_orders (z_orders, 2, 1, 3, 0, 5, 4);
1177 }
1178 break;
1180 case Box3D::Z:
1181 if (box3d_half_line_crosses_joining_line(vpx, vpz, corner3, corner1)) {
1182 // degenerate case
1183 //g_print ("Degenerate case #2\n");
1184 box3d_aux_set_z_orders (z_orders, 2, 0, 1, 4, 3, 5);
1185 } else if (box3d_half_line_crosses_joining_line(vpx, vpy, corner3, corner7)) {
1186 // degenerate case
1187 //g_print ("Degenerate case #3\n");
1188 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 5, 3, 4);
1189 } else {
1190 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 3, 4, 5);
1191 }
1192 break;
1194 case Box3D::X:
1195 if (box3d_half_line_crosses_joining_line(vpz, vpx, corner3, corner1)) {
1196 // degenerate case
1197 //g_print ("Degenerate case #4\n");
1198 box3d_aux_set_z_orders (z_orders, 2, 1, 0, 4, 5, 3);
1199 } else {
1200 box3d_aux_set_z_orders (z_orders, 2, 4, 0, 5, 1, 3);
1201 }
1202 break;
1204 case Box3D::NONE:
1205 box3d_aux_set_z_orders (z_orders, 2, 3, 4, 1, 0, 5);
1206 break;
1208 default:
1209 g_assert_not_reached();
1210 break;
1211 } // end default case
1212 }
1214 // TODO: If there are still errors in z-orders of everted boxes, we need to choose a variable corner
1215 // instead of the hard-coded corner #3 in the computations above
1216 Box3D::Axis ev = box3d_everted_directions(box);
1217 for (int i = 0; i < 3; ++i) {
1218 if (ev & Box3D::axes[i]) {
1219 box3d_swap_sides(z_orders, Box3D::axes[i]);
1220 }
1221 }
1223 // Check whether anything actually changed
1224 for (int i = 0; i < 6; ++i) {
1225 if (box->z_orders[i] != z_orders[i]) {
1226 for (int j = i; j < 6; ++j) {
1227 box->z_orders[j] = z_orders[j];
1228 }
1229 return true;
1230 }
1231 }
1232 return false;
1233 }
1235 static std::map<int, Box3DSide *>
1236 box3d_get_sides (SPBox3D *box) {
1237 std::map<int, Box3DSide *> sides;
1238 for (SPObject *side = sp_object_first_child(box); side != NULL; side = SP_OBJECT_NEXT(side)) {
1239 sides[Box3D::face_to_int(sp_repr_get_int_attribute(SP_OBJECT_REPR(side),
1240 "inkscape:box3dsidetype", -1))] = SP_BOX3D_SIDE(side);
1241 }
1242 sides.erase(-1);
1243 return sides;
1244 }
1247 // TODO: Check whether the box is everted in any direction and swap the sides opposite to this direction
1248 void
1249 box3d_set_z_orders (SPBox3D *box) {
1250 // For efficiency reasons, we only set the new z-orders if something really changed
1251 if (box3d_recompute_z_orders (box)) {
1252 std::map<int, Box3DSide *> sides = box3d_get_sides(box);
1253 std::map<int, Box3DSide *>::iterator side;
1254 for (unsigned int i = 0; i < 6; ++i) {
1255 side = sides.find(box->z_orders[i]);
1256 if (side != sides.end()) {
1257 SP_ITEM((*side).second)->lowerToBottom();
1258 }
1259 }
1260 /**
1261 g_print ("Resetting z-orders: ");
1262 for (int i = 0; i < 6; ++i) {
1263 g_print ("%d ", box->z_orders[i]);
1264 }
1265 g_print ("\n");
1266 **/
1267 }
1268 }
1270 /*
1271 * Auxiliary function for z-order recomputing:
1272 * Determines whether \a pt lies in the sector formed by the two PLs from the corners with IDs
1273 * \a i21 and \a id2 to the VP in direction \a axis. If the VP is infinite, we say that \a pt
1274 * lies in the sector if it lies between the two (parallel) PLs.
1275 * \ret * 0 if \a pt doesn't lie in the sector
1276 * * 1 if \a pt lies in the sector and either VP is finite of VP is infinite and the direction
1277 * from the edge between the two corners to \a pt points towards the VP
1278 * * -1 otherwise
1279 */
1280 // TODO: Maybe it would be useful to have a similar method for projective points pt because then we
1281 // can use it for VPs and perhaps merge the case distinctions during z-order recomputation.
1282 int
1283 box3d_pt_lies_in_PL_sector (SPBox3D const *box, NR::Point const &pt, int id1, int id2, Box3D::Axis axis) {
1284 Persp3D *persp = box->persp_ref->getObject();
1286 // the two corners
1287 NR::Point c1(box3d_get_corner_screen(box, id1));
1288 NR::Point c2(box3d_get_corner_screen(box, id2));
1290 int ret = 0;
1291 if (persp3d_VP_is_finite(persp, Box3D::toProj(axis))) {
1292 NR::Point vp(persp3d_get_VP(persp, Box3D::toProj(axis)).affine());
1293 NR::Point v1(c1 - vp);
1294 NR::Point v2(c2 - vp);
1295 NR::Point w(pt - vp);
1296 ret = static_cast<int>(Box3D::lies_in_sector(v1, v2, w));
1297 //g_print ("Case 0 - returning %d\n", ret);
1298 } else {
1299 Box3D::PerspectiveLine pl1(c1, Box3D::toProj(axis), persp);
1300 Box3D::PerspectiveLine pl2(c2, Box3D::toProj(axis), persp);
1301 if (pl1.lie_on_same_side(pt, c2) && pl2.lie_on_same_side(pt, c1)) {
1302 // test whether pt lies "towards" or "away from" the VP
1303 Box3D::Line edge(c1,c2);
1304 NR::Point c3(box3d_get_corner_screen(box, id1 ^ axis));
1305 if (edge.lie_on_same_side(pt, c3)) {
1306 ret = 1;
1307 } else {
1308 ret = -1;
1309 }
1310 }
1311 //g_print ("Case 1 - returning %d\n", ret);
1312 }
1313 return ret;
1314 }
1316 int
1317 box3d_VP_lies_in_PL_sector (SPBox3D const *box, Proj::Axis vpdir, int id1, int id2, Box3D::Axis axis) {
1318 Persp3D *persp = box->persp_ref->getObject();
1320 if (!persp3d_VP_is_finite(persp, vpdir)) {
1321 return 0;
1322 } else {
1323 return box3d_pt_lies_in_PL_sector(box, persp3d_get_VP(persp, vpdir).affine(), id1, id2, axis);
1324 }
1325 }
1327 /* swap the coordinates of corner0 and corner7 along the specified axis */
1328 static void
1329 box3d_swap_coords(SPBox3D *box, Proj::Axis axis, bool smaller = true) {
1330 box->orig_corner0.normalize();
1331 box->orig_corner7.normalize();
1332 if ((box->orig_corner0[axis] < box->orig_corner7[axis]) != smaller) {
1333 double tmp = box->orig_corner0[axis];
1334 box->orig_corner0[axis] = box->orig_corner7[axis];
1335 box->orig_corner7[axis] = tmp;
1336 }
1337 // FIXME: Should we also swap the coordinates of save_corner0 and save_corner7?
1338 }
1340 /* ensure that the coordinates of corner0 and corner7 are in the correct order (to prevent everted boxes) */
1341 void
1342 box3d_relabel_corners(SPBox3D *box) {
1343 box3d_swap_coords(box, Proj::X, false);
1344 box3d_swap_coords(box, Proj::Y, false);
1345 box3d_swap_coords(box, Proj::Z, true);
1346 }
1348 void
1349 box3d_switch_perspectives(SPBox3D *box, Persp3D *old_persp, Persp3D *new_persp) {
1350 persp3d_remove_box (old_persp, box);
1351 persp3d_add_box (new_persp, box);
1352 gchar *href = g_strdup_printf("#%s", SP_OBJECT_REPR(new_persp)->attribute("id"));
1353 SP_OBJECT_REPR(box)->setAttribute("inkscape:perspectiveID", href);
1354 g_free(href);
1355 }
1358 /*
1359 Local Variables:
1360 mode:c++
1361 c-file-style:"stroustrup"
1362 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1363 indent-tabs-mode:nil
1364 fill-column:99
1365 End:
1366 */
1367 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :