Code

simplify code that puts anchors at start and end of paths in draw context.
[inkscape.git] / src / draw-context.cpp
1 #define __SP_DRAW_CONTEXT_C__
3 /*
4  * Generic drawing context
5  *
6  * Author:
7  *   Lauris Kaplinski <lauris@kaplinski.com>
8  *
9  * Copyright (C) 2000 Lauris Kaplinski
10  * Copyright (C) 2000-2001 Ximian, Inc.
11  * Copyright (C) 2002 Lauris Kaplinski
12  *
13  * Released under GNU GPL, read the file 'COPYING' for more information
14  */
16 #define DRAW_VERBOSE
18 #ifdef HAVE_CONFIG_H
19 # include "config.h"
20 #endif
21 #include <gdk/gdkkeysyms.h>
23 #include "display/canvas-bpath.h"
24 #include "xml/repr.h"
25 #include "svg/svg.h"
26 #include <glibmm/i18n.h>
27 #include "libnr/n-art-bpath.h"
28 #include "display/curve.h"
29 #include "desktop.h"
30 #include "desktop-affine.h"
31 #include "desktop-handles.h"
32 #include "desktop-style.h"
33 #include "document.h"
34 #include "draw-anchor.h"
35 #include "macros.h"
36 #include "message-stack.h"
37 #include "pen-context.h"
38 #include "prefs-utils.h"
39 #include "selection.h"
40 #include "selection-chemistry.h"
41 #include "snap.h"
42 #include "sp-path.h"
43 #include "sp-namedview.h"
45 static void sp_draw_context_class_init(SPDrawContextClass *klass);
46 static void sp_draw_context_init(SPDrawContext *dc);
47 static void sp_draw_context_dispose(GObject *object);
49 static void sp_draw_context_setup(SPEventContext *ec);
50 static void sp_draw_context_set(SPEventContext *ec, gchar const *key, gchar const *value);
51 static void sp_draw_context_finish(SPEventContext *ec);
53 static gint sp_draw_context_root_handler(SPEventContext *event_context, GdkEvent *event);
55 static void spdc_selection_changed(Inkscape::Selection *sel, SPDrawContext *dc);
56 static void spdc_selection_modified(Inkscape::Selection *sel, guint flags, SPDrawContext *dc);
58 static void spdc_attach_selection(SPDrawContext *dc, Inkscape::Selection *sel);
60 static void spdc_flush_white(SPDrawContext *dc, SPCurve *gc);
62 static void spdc_reset_white(SPDrawContext *dc);
63 static void spdc_free_colors(SPDrawContext *dc);
66 static SPEventContextClass *draw_parent_class;
69 GType
70 sp_draw_context_get_type(void)
71 {
72     static GType type = 0;
73     if (!type) {
74         GTypeInfo info = {
75             sizeof(SPDrawContextClass),
76             NULL, NULL,
77             (GClassInitFunc) sp_draw_context_class_init,
78             NULL, NULL,
79             sizeof(SPDrawContext),
80             4,
81             (GInstanceInitFunc) sp_draw_context_init,
82             NULL,   /* value_table */
83         };
84         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPDrawContext", &info, (GTypeFlags)0);
85     }
86     return type;
87 }
89 static void
90 sp_draw_context_class_init(SPDrawContextClass *klass)
91 {
92     GObjectClass *object_class;
93     SPEventContextClass *ec_class;
95     object_class = (GObjectClass *)klass;
96     ec_class = (SPEventContextClass *) klass;
98     draw_parent_class = (SPEventContextClass*)g_type_class_peek_parent(klass);
100     object_class->dispose = sp_draw_context_dispose;
102     ec_class->setup = sp_draw_context_setup;
103     ec_class->set = sp_draw_context_set;
104     ec_class->finish = sp_draw_context_finish;
105     ec_class->root_handler = sp_draw_context_root_handler;
108 static void
109 sp_draw_context_init(SPDrawContext *dc)
111     dc->attach = FALSE;
113     dc->red_color = 0xff00007f;
114     dc->blue_color = 0x0000ff7f;
115     dc->green_color = 0x00ff007f;
116     dc->red_curve_is_valid = false;
118     dc->waiting_LPE = Inkscape::LivePathEffect::INVALID_LPE;
120     new (&dc->sel_changed_connection) sigc::connection();
121     new (&dc->sel_modified_connection) sigc::connection();
124 static void
125 sp_draw_context_dispose(GObject *object)
127     SPDrawContext *dc = SP_DRAW_CONTEXT(object);
129     dc->sel_changed_connection.~connection();
130     dc->sel_modified_connection.~connection();
132     if (dc->grab) {
133         sp_canvas_item_ungrab(dc->grab, GDK_CURRENT_TIME);
134         dc->grab = NULL;
135     }
137     if (dc->selection) {
138         dc->selection = NULL;
139     }
141     spdc_free_colors(dc);
143     G_OBJECT_CLASS(draw_parent_class)->dispose(object);
146 static void
147 sp_draw_context_setup(SPEventContext *ec)
149     SPDrawContext *dc = SP_DRAW_CONTEXT(ec);
150     SPDesktop *dt = ec->desktop;
152     if (((SPEventContextClass *) draw_parent_class)->setup) {
153         ((SPEventContextClass *) draw_parent_class)->setup(ec);
154     }
156     dc->selection = sp_desktop_selection(dt);
158     /* Connect signals to track selection changes */
159     dc->sel_changed_connection = dc->selection->connectChanged(
160         sigc::bind(sigc::ptr_fun(&spdc_selection_changed), dc)
161     );
162     dc->sel_modified_connection = dc->selection->connectModified(
163         sigc::bind(sigc::ptr_fun(&spdc_selection_modified), dc)
164     );
166     /* Create red bpath */
167     dc->red_bpath = sp_canvas_bpath_new(sp_desktop_sketch(ec->desktop), NULL);
168     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->red_bpath), dc->red_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
169     /* Create red curve */
170     dc->red_curve = new SPCurve(4);
172     /* Create blue bpath */
173     dc->blue_bpath = sp_canvas_bpath_new(sp_desktop_sketch(ec->desktop), NULL);
174     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->blue_bpath), dc->blue_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
175     /* Create blue curve */
176     dc->blue_curve = new SPCurve(8);
178     /* Create green curve */
179     dc->green_curve = new SPCurve(64);
180     /* No green anchor by default */
181     dc->green_anchor = NULL;
182     dc->green_closed = FALSE;
184     dc->attach = TRUE;
185     spdc_attach_selection(dc, dc->selection);
188 static void
189 sp_draw_context_finish(SPEventContext *ec)
191     SPDrawContext *dc = SP_DRAW_CONTEXT(ec);
193     dc->sel_changed_connection.disconnect();
194     dc->sel_modified_connection.disconnect();
196     if (dc->grab) {
197         sp_canvas_item_ungrab(dc->grab, GDK_CURRENT_TIME);
198     }
200     if (dc->selection) {
201         dc->selection = NULL;
202     }
204     spdc_free_colors(dc);
207 static void
208 sp_draw_context_set(SPEventContext */*ec*/, const gchar */*key*/, const gchar */*value*/)
212 gint
213 sp_draw_context_root_handler(SPEventContext *ec, GdkEvent *event)
215     gint ret = FALSE;
217     switch (event->type) {
218         case GDK_KEY_PRESS:
219             switch (get_group0_keyval (&event->key)) {
220                 case GDK_Up:
221                 case GDK_Down:
222                 case GDK_KP_Up:
223                 case GDK_KP_Down:
224                     // prevent the zoom field from activation
225                     if (!MOD__CTRL_ONLY) {
226                         ret = TRUE;
227                     }
228                     break;
229                 default:
230             break;
231         }
232         break;
233     default:
234         break;
235     }
237     if (!ret) {
238         if (((SPEventContextClass *) draw_parent_class)->root_handler) {
239             ret = ((SPEventContextClass *) draw_parent_class)->root_handler(ec, event);
240         }
241     }
243     return ret;
246 /*
247  * If we have an item and a waiting LPE, apply the effect to the item
248  */
249 void
250 spdc_check_for_and_apply_waiting_LPE(SPDrawContext *dc, SPItem *item)
252     using namespace Inkscape::LivePathEffect;
254     // TODO: sort this out as soon as we use automatic LPE application for other things than spiro mode, too
255     if (item) {
256         if (prefs_get_int_attribute("tools.freehand", "spiro-spline-mode", 0)) {
257             Effect::createAndApply(SPIRO, dc->desktop->doc(), item);
258             return;
259         }
260         if (dc->waiting_LPE != INVALID_LPE) {
261             Effect::createAndApply(dc->waiting_LPE, dc->desktop->doc(), item);
262         }
263     }
266 /*
267  * Selection handlers
268  */
270 static void
271 spdc_selection_changed(Inkscape::Selection *sel, SPDrawContext *dc)
273     spdc_check_for_and_apply_waiting_LPE(dc, sel->singleItem());
275     if (dc->attach) {
276         spdc_attach_selection(dc, sel);
277     }
280 /* fixme: We have to ensure this is not delayed (Lauris) */
282 static void
283 spdc_selection_modified(Inkscape::Selection *sel, guint /*flags*/, SPDrawContext *dc)
285     if (dc->attach) {
286         spdc_attach_selection(dc, sel);
287     }
290 static void
291 spdc_attach_selection(SPDrawContext *dc, Inkscape::Selection */*sel*/)
293     /* We reset white and forget white/start/end anchors */
294     spdc_reset_white(dc);
295     dc->sa = NULL;
296     dc->ea = NULL;
298     SPItem *item = dc->selection ? dc->selection->singleItem() : NULL;
300     if ( item && SP_IS_PATH(item) ) {
301         /* Create new white data */
302         /* Item */
303         dc->white_item = item;
304         /* Curve list */
305         /* We keep it in desktop coordinates to eliminate calculation errors */
306         SPCurve *norm = sp_path_get_curve_for_edit (SP_PATH(item));
307         norm->transform(sp_item_i2d_affine(dc->white_item));
308         g_return_if_fail( norm != NULL );
309         dc->white_curves = g_slist_reverse(norm->split());
310         norm->unref();
311         /* Anchor list */
312         for (GSList *l = dc->white_curves; l != NULL; l = l->next) {
313             SPCurve *c;
314             c = (SPCurve*)l->data;
315             g_return_if_fail( c->get_length() > 1 );
316             if ( !c->is_closed() ) {
317                 SPDrawAnchor *a;
318                 a = sp_draw_anchor_new(dc, c, TRUE, c->first_point());
319                 dc->white_anchors = g_slist_prepend(dc->white_anchors, a);
320                 a = sp_draw_anchor_new(dc, c, FALSE, c->last_point());
321                 dc->white_anchors = g_slist_prepend(dc->white_anchors, a);
322             }
323         }
324         /* fixme: recalculate active anchor? */
325     }
329 /**
330  *  Snaps node or handle to PI/rotationsnapsperpi degree increments.
331  *
332  *  \param dc draw context
333  *  \param p cursor point (to be changed by snapping)
334  *  \param o origin point
335  *  \param state  keyboard state to check if ctrl was pressed
336 */
338 void spdc_endpoint_snap_rotation(SPEventContext const *const ec, NR::Point &p, NR::Point const o,
339                                  guint state)
341     /* Control must be down for this snap to work */
342     if ((state & GDK_CONTROL_MASK) == 0) {
343         return;
344     }
346     unsigned const snaps = abs(prefs_get_int_attribute("options.rotationsnapsperpi", "value", 12));
347     /* 0 means no snapping. */
349     /* mirrored by fabs, so this corresponds to 15 degrees */
350     NR::Point best; /* best solution */
351     double bn = NR_HUGE; /* best normal */
352     double bdot = 0;
353     NR::Point v = NR::Point(0, 1);
354     double const r00 = cos(M_PI / snaps), r01 = sin(M_PI / snaps);
355     double const r10 = -r01, r11 = r00;
357     NR::Point delta = p - o;
359     for (unsigned i = 0; i < snaps; i++) {
360         double const ndot = fabs(dot(v,NR::rot90(delta)));
361         NR::Point t(r00*v[NR::X] + r01*v[NR::Y],
362                     r10*v[NR::X] + r11*v[NR::Y]);
363         if (ndot < bn) {
364             /* I think it is better numerically to use the normal, rather than the dot product
365              * to assess solutions, but I haven't proven it. */
366             bn = ndot;
367             best = v;
368             bdot = dot(v, delta);
369         }
370         v = t;
371     }
373     if (fabs(bdot) > 0) {
374         p = o + bdot * best;
376         /* Snap it along best vector */
377         SnapManager &m = SP_EVENT_CONTEXT_DESKTOP(ec)->namedview->snap_manager;
378         m.setup(SP_EVENT_CONTEXT_DESKTOP(ec), NULL);
379         m.constrainedSnapReturnByRef( Inkscape::Snapper::SNAPPOINT_NODE, p, Inkscape::Snapper::ConstraintLine(best));
380     }
384 void spdc_endpoint_snap_free(SPEventContext const * const ec, NR::Point& p, guint const state)
386     /* Shift disables this snap */
387     if (state & GDK_SHIFT_MASK) {
388         return;
389     }
391     SnapManager &m = SP_EVENT_CONTEXT_DESKTOP(ec)->namedview->snap_manager;
392     m.setup(SP_EVENT_CONTEXT_DESKTOP(ec), NULL);
393     m.freeSnapReturnByRef(Inkscape::Snapper::SNAPPOINT_NODE, p);
396 static SPCurve *
397 reverse_then_unref(SPCurve *orig)
399     SPCurve *ret = orig->create_reverse();
400     orig->unref();
401     return ret;
404 /**
405  * Concats red, blue and green.
406  * If any anchors are defined, process these, optionally removing curves from white list
407  * Invoke _flush_white to write result back to object.
408  */
409 void
410 spdc_concat_colors_and_flush(SPDrawContext *dc, gboolean forceclosed)
412     /* Concat RBG */
413     SPCurve *c = dc->green_curve;
415     /* Green */
416     dc->green_curve = new SPCurve(64);
417     while (dc->green_bpaths) {
418         gtk_object_destroy(GTK_OBJECT(dc->green_bpaths->data));
419         dc->green_bpaths = g_slist_remove(dc->green_bpaths, dc->green_bpaths->data);
420     }
421     /* Blue */
422     c->append_continuous(dc->blue_curve, 0.0625);
423     dc->blue_curve->reset();
424     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->blue_bpath), NULL);
425     /* Red */
426     if (dc->red_curve_is_valid) {
427         c->append_continuous(dc->red_curve, 0.0625);
428     }
429     dc->red_curve->reset();
430     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->red_bpath), NULL);
432     if (c->is_empty()) {
433         c->unref();
434         return;
435     }
437     /* Step A - test, whether we ended on green anchor */
438     if ( forceclosed || ( dc->green_anchor && dc->green_anchor->active ) ) {
439         // We hit green anchor, closing Green-Blue-Red
440         SP_EVENT_CONTEXT_DESKTOP(dc)->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Path is closed."));
441         c->closepath_current();
442         /* Closed path, just flush */
443         spdc_flush_white(dc, c);
444         c->unref();
445         return;
446     }
448     /* Step B - both start and end anchored to same curve */
449     if ( dc->sa && dc->ea
450          && ( dc->sa->curve == dc->ea->curve )
451          && ( ( dc->sa != dc->ea )
452               || dc->sa->curve->is_closed() ) )
453     {
454         // We hit bot start and end of single curve, closing paths
455         SP_EVENT_CONTEXT_DESKTOP(dc)->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Closing path."));
456         if (dc->sa->start && !(dc->sa->curve->is_closed()) ) {
457             c = reverse_then_unref(c);
458         }
459         dc->sa->curve->append_continuous(c, 0.0625);
460         c->unref();
461         dc->sa->curve->closepath_current();
462         spdc_flush_white(dc, NULL);
463         return;
464     }
466     /* Step C - test start */
467     if (dc->sa) {
468         SPCurve *s = dc->sa->curve;
469         dc->white_curves = g_slist_remove(dc->white_curves, s);
470         if (dc->sa->start) {
471             s = reverse_then_unref(s);
472         }
473         s->append_continuous(c, 0.0625);
474         c->unref();
475         c = s;
476     } else /* Step D - test end */ if (dc->ea) {
477         SPCurve *e = dc->ea->curve;
478         dc->white_curves = g_slist_remove(dc->white_curves, e);
479         if (!dc->ea->start) {
480             e = reverse_then_unref(e);
481         }
482         c->append_continuous(e, 0.0625);
483         e->unref();
484     }
487     spdc_flush_white(dc, c);
489     c->unref();
492 static char const *
493 tool_name(SPDrawContext *dc)
495     return ( SP_IS_PEN_CONTEXT(dc)
496              ? "tools.freehand.pen"
497              : "tools.freehand.pencil" );
500 /*
501  * Flushes white curve(s) and additional curve into object
502  *
503  * No cleaning of colored curves - this has to be done by caller
504  * No rereading of white data, so if you cannot rely on ::modified, do it in caller
505  *
506  */
508 static void
509 spdc_flush_white(SPDrawContext *dc, SPCurve *gc)
511     SPCurve *c;
513     if (dc->white_curves) {
514         g_assert(dc->white_item);
515         c = SPCurve::concat(dc->white_curves);
516         g_slist_free(dc->white_curves);
517         dc->white_curves = NULL;
518         if (gc) {
519             c->append(gc, FALSE);
520         }
521     } else if (gc) {
522         c = gc;
523         c->ref();
524     } else {
525         return;
526     }
528     /* Now we have to go back to item coordinates at last */
529     c->transform(( dc->white_item
530                             ? sp_item_dt2i_affine(dc->white_item)
531                             : sp_desktop_dt2root_affine(SP_EVENT_CONTEXT_DESKTOP(dc)) ));
533     SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
534     SPDocument *doc = sp_desktop_document(desktop);
535     Inkscape::XML::Document *xml_doc = sp_document_repr_doc(doc);
537     if ( c && !c->is_empty() ) {
538         /* We actually have something to write */
540         bool has_lpe = false;
541         Inkscape::XML::Node *repr;
542         if (dc->white_item) {
543             repr = SP_OBJECT_REPR(dc->white_item);
544             has_lpe = sp_lpe_item_has_path_effect_recursive(SP_LPE_ITEM(dc->white_item));
545         } else {
546             repr = xml_doc->createElement("svg:path");
547             /* Set style */
548             sp_desktop_apply_style_tool(desktop, repr, tool_name(dc), false);
549         }
551         gchar *str = sp_svg_write_path( c->get_pathvector() );
552         g_assert( str != NULL );
553         if (has_lpe)
554             repr->setAttribute("inkscape:original-d", str);
555         else
556             repr->setAttribute("d", str);
557         g_free(str);
559         if (!dc->white_item) {
560             /* Attach repr */
561             SPItem *item = SP_ITEM(desktop->currentLayer()->appendChildRepr(repr));
562             dc->selection->set(repr);
563             Inkscape::GC::release(repr);
564             item->transform = i2i_affine(desktop->currentRoot(), desktop->currentLayer());
565             item->updateRepr();
566         }
568         sp_document_done(doc, SP_IS_PEN_CONTEXT(dc)? SP_VERB_CONTEXT_PEN : SP_VERB_CONTEXT_PENCIL, 
569                          _("Draw path"));
571         // When quickly drawing several subpaths with Shift, the next subpath may be finished and
572         // flushed before the selection_modified signal is fired by the previous change, which
573         // results in the tool losing all of the selected path's curve except that last subpath. To
574         // fix this, we force the selection_modified callback now, to make sure the tool's curve is
575         // in sync immediately.
576         spdc_selection_modified(sp_desktop_selection(desktop), 0, dc);
577     }
579     c->unref();
581     /* Flush pending updates */
582     sp_document_ensure_up_to_date(doc);
585 /**
586  * Returns FIRST active anchor (the activated one).
587  */
588 SPDrawAnchor *
589 spdc_test_inside(SPDrawContext *dc, NR::Point p)
591     SPDrawAnchor *active = NULL;
593     /* Test green anchor */
594     if (dc->green_anchor) {
595         active = sp_draw_anchor_test(dc->green_anchor, p, TRUE);
596     }
598     for (GSList *l = dc->white_anchors; l != NULL; l = l->next) {
599         SPDrawAnchor *na = sp_draw_anchor_test((SPDrawAnchor *) l->data, p, !active);
600         if ( !active && na ) {
601             active = na;
602         }
603     }
605     return active;
608 static void
609 spdc_reset_white(SPDrawContext *dc)
611     if (dc->white_item) {
612         /* We do not hold refcount */
613         dc->white_item = NULL;
614     }
615     while (dc->white_curves) {
616         reinterpret_cast<SPCurve *>(dc->white_curves->data)->unref();
617         dc->white_curves = g_slist_remove(dc->white_curves, dc->white_curves->data);
618     }
619     while (dc->white_anchors) {
620         sp_draw_anchor_destroy((SPDrawAnchor *) dc->white_anchors->data);
621         dc->white_anchors = g_slist_remove(dc->white_anchors, dc->white_anchors->data);
622     }
625 static void
626 spdc_free_colors(SPDrawContext *dc)
628     /* Red */
629     if (dc->red_bpath) {
630         gtk_object_destroy(GTK_OBJECT(dc->red_bpath));
631         dc->red_bpath = NULL;
632     }
633     if (dc->red_curve) {
634         dc->red_curve = dc->red_curve->unref();
635     }
636     /* Blue */
637     if (dc->blue_bpath) {
638         gtk_object_destroy(GTK_OBJECT(dc->blue_bpath));
639         dc->blue_bpath = NULL;
640     }
641     if (dc->blue_curve) {
642         dc->blue_curve = dc->blue_curve->unref();
643     }
644     /* Green */
645     while (dc->green_bpaths) {
646         gtk_object_destroy(GTK_OBJECT(dc->green_bpaths->data));
647         dc->green_bpaths = g_slist_remove(dc->green_bpaths, dc->green_bpaths->data);
648     }
649     if (dc->green_curve) {
650         dc->green_curve = dc->green_curve->unref();
651     }
652     if (dc->green_anchor) {
653         dc->green_anchor = sp_draw_anchor_destroy(dc->green_anchor);
654     }
655     /* White */
656     if (dc->white_item) {
657         /* We do not hold refcount */
658         dc->white_item = NULL;
659     }
660     while (dc->white_curves) {
661         reinterpret_cast<SPCurve *>(dc->white_curves->data)->unref();
662         dc->white_curves = g_slist_remove(dc->white_curves, dc->white_curves->data);
663     }
664     while (dc->white_anchors) {
665         sp_draw_anchor_destroy((SPDrawAnchor *) dc->white_anchors->data);
666         dc->white_anchors = g_slist_remove(dc->white_anchors, dc->white_anchors->data);
667     }
671 /*
672   Local Variables:
673   mode:c++
674   c-file-style:"stroustrup"
675   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
676   indent-tabs-mode:nil
677   fill-column:99
678   End:
679 */
680 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :