Code

Implementing feature request #1673807: snapping of gradient handles
[inkscape.git] / src / arc-context.cpp
1 #define __SP_ARC_CONTEXT_C__
3 /** \file Ellipse drawing context. */
5 /*
6  * Authors:
7  *   Mitsuru Oka
8  *   Lauris Kaplinski <lauris@kaplinski.com>
9  *   bulia byak <buliabyak@users.sf.net>
10  *
11  * Copyright (C) 2006      Johan Engelen <johan@shouraizou.nl>
12  * Copyright (C) 2002      Mitsuru Oka
13  * Copyright (C) 2000-2002 Lauris Kaplinski
14  * Copyright (C) 2000-2001 Ximian, Inc.
15  *
16  * Released under GNU GPL, read the file 'COPYING' for more information
17  */
19 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22 #include <gdk/gdkkeysyms.h>
24 #include "macros.h"
25 #include <glibmm/i18n.h>
26 #include "display/sp-canvas.h"
27 #include "sp-ellipse.h"
28 #include "document.h"
29 #include "sp-namedview.h"
30 #include "selection.h"
31 #include "desktop-handles.h"
32 #include "snap.h"
33 #include "pixmaps/cursor-ellipse.xpm"
34 #include "sp-metrics.h"
35 #include "xml/repr.h"
36 #include "xml/node-event-vector.h"
37 #include "object-edit.h"
38 #include "prefs-utils.h"
39 #include "message-context.h"
40 #include "desktop.h"
41 #include "desktop-style.h"
42 #include "context-fns.h"
43 #include "verbs.h"
45 #include "arc-context.h"
47 static void sp_arc_context_class_init(SPArcContextClass *klass);
48 static void sp_arc_context_init(SPArcContext *arc_context);
49 static void sp_arc_context_dispose(GObject *object);
51 static void sp_arc_context_setup(SPEventContext *ec);
52 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event);
53 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event);
55 static void sp_arc_drag(SPArcContext *ec, NR::Point pt, guint state);
56 static void sp_arc_finish(SPArcContext *ec);
58 static SPEventContextClass *parent_class;
60 GtkType sp_arc_context_get_type()
61 {
62     static GType type = 0;
63     if (!type) {
64         GTypeInfo info = {
65             sizeof(SPArcContextClass),
66             NULL, NULL,
67             (GClassInitFunc) sp_arc_context_class_init,
68             NULL, NULL,
69             sizeof(SPArcContext),
70             4,
71             (GInstanceInitFunc) sp_arc_context_init,
72             NULL,   /* value_table */
73         };
74         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPArcContext", &info, (GTypeFlags) 0);
75     }
76     return type;
77 }
79 static void sp_arc_context_class_init(SPArcContextClass *klass)
80 {
82     GObjectClass *object_class = (GObjectClass *) klass;
83     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
85     parent_class = (SPEventContextClass*) g_type_class_peek_parent(klass);
87     object_class->dispose = sp_arc_context_dispose;
89     event_context_class->setup = sp_arc_context_setup;
90     event_context_class->root_handler = sp_arc_context_root_handler;
91     event_context_class->item_handler = sp_arc_context_item_handler;
92 }
94 static void sp_arc_context_init(SPArcContext *arc_context)
95 {
96     SPEventContext *event_context = SP_EVENT_CONTEXT(arc_context);
98     event_context->cursor_shape = cursor_ellipse_xpm;
99     event_context->hot_x = 4;
100     event_context->hot_y = 4;
101     event_context->xp = 0;
102     event_context->yp = 0;
103     event_context->tolerance = 0;
104     event_context->within_tolerance = false;
105     event_context->item_to_select = NULL;
107     event_context->shape_repr = NULL;
108     event_context->shape_knot_holder = NULL;
110     arc_context->item = NULL;
112     new (&arc_context->sel_changed_connection) sigc::connection();
115 static void sp_arc_context_dispose(GObject *object)
117     SPEventContext *ec = SP_EVENT_CONTEXT(object);
118     SPArcContext *ac = SP_ARC_CONTEXT(object);
120     ec->enableGrDrag(false);
122     ac->sel_changed_connection.disconnect();
123     ac->sel_changed_connection.~connection();
125     if (ec->shape_knot_holder) {
126         sp_knot_holder_destroy(ec->shape_knot_holder);
127         ec->shape_knot_holder = NULL;
128     }
130     if (ec->shape_repr) { // remove old listener
131         sp_repr_remove_listener_by_data(ec->shape_repr, ec);
132         Inkscape::GC::release(ec->shape_repr);
133         ec->shape_repr = 0;
134     }
136     /* fixme: This is necessary because we do not grab */
137     if (ac->item) {
138         sp_arc_finish(ac);
139     }
141     delete ac->_message_context;
143     G_OBJECT_CLASS(parent_class)->dispose(object);
146 static Inkscape::XML::NodeEventVector ec_shape_repr_events = {
147     NULL, /* child_added */
148     NULL, /* child_removed */
149     ec_shape_event_attr_changed,
150     NULL, /* content_changed */
151     NULL  /* order_changed */
152 };
154 /**
155 \brief  Callback that processes the "changed" signal on the selection;
156 destroys old and creates new knotholder.
157 */
158 void sp_arc_context_selection_changed(Inkscape::Selection * selection, gpointer data)
160     SPArcContext *ac = SP_ARC_CONTEXT(data);
161     SPEventContext *ec = SP_EVENT_CONTEXT(ac);
163     if (ec->shape_knot_holder) { // desktroy knotholder
164         sp_knot_holder_destroy(ec->shape_knot_holder);
165         ec->shape_knot_holder = NULL;
166     }
168     if (ec->shape_repr) { // remove old listener
169         sp_repr_remove_listener_by_data(ec->shape_repr, ec);
170         Inkscape::GC::release(ec->shape_repr);
171         ec->shape_repr = 0;
172     }
174     SPItem *item = selection ? selection->singleItem() : NULL;
175     if (item) {
176         ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
177         Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
178         if (shape_repr) {
179             ec->shape_repr = shape_repr;
180             Inkscape::GC::anchor(shape_repr);
181             sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
182         }
183     }
186 static void sp_arc_context_setup(SPEventContext *ec)
188     SPArcContext *ac = SP_ARC_CONTEXT(ec);
189     Inkscape::Selection *selection = sp_desktop_selection(ec->desktop);
191     if (((SPEventContextClass *) parent_class)->setup) {
192         ((SPEventContextClass *) parent_class)->setup(ec);
193     }
195     SPItem *item = selection->singleItem();
197     if (item) {
198         ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
199         Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
200         if (shape_repr) {
201             ec->shape_repr = shape_repr;
202             Inkscape::GC::anchor(shape_repr);
203             sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
204         }
205     }
207     ac->sel_changed_connection.disconnect();
208     ac->sel_changed_connection = selection->connectChanged(
209         sigc::bind(sigc::ptr_fun(&sp_arc_context_selection_changed), (gpointer) ac)
210         );
212     if (prefs_get_int_attribute("tools.shapes", "selcue", 0) != 0) {
213         ec->enableSelectionCue();
214     }
216     if (prefs_get_int_attribute("tools.shapes", "gradientdrag", 0) != 0) {
217         ec->enableGrDrag();
218     }
220     ac->_message_context = new Inkscape::MessageContext(ec->desktop->messageStack());
223 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event)
225     SPDesktop *desktop = event_context->desktop;
226     gint ret = FALSE;
228     switch (event->type) {
229         case GDK_BUTTON_PRESS:
230             if (event->button.button == 1) {
231                 Inkscape::setup_for_drag_start(desktop, event_context, event);
232                 ret = TRUE;
233             }
234             break;
235             // motion and release are always on root (why?)
236         default:
237             break;
238     }
240     if (((SPEventContextClass *) parent_class)->item_handler) {
241         ret = ((SPEventContextClass *) parent_class)->item_handler(event_context, item, event);
242     }
244     return ret;
247 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event)
249     static bool dragging;
251     SPDesktop *desktop = event_context->desktop;
252     Inkscape::Selection *selection = sp_desktop_selection(desktop);
253     SPArcContext *ac = SP_ARC_CONTEXT(event_context);
255     event_context->tolerance = prefs_get_int_attribute_limited("options.dragtolerance", "value", 0, 0, 100);
257     gint ret = FALSE;
259     switch (event->type) {
260         case GDK_BUTTON_PRESS:
261             if (event->button.button == 1) {
263                 dragging = true;
264                 ac->center = Inkscape::setup_for_drag_start(desktop, event_context, event);
266                 SnapManager const &m = desktop->namedview->snap_manager;                
267                 ac->center = m.freeSnap(Inkscape::Snapper::BBOX_POINT | Inkscape::Snapper::SNAP_POINT, ac->center, ac->item).getPoint();
268                 
269                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
270                                     GDK_KEY_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
271                                     GDK_POINTER_MOTION_MASK | GDK_BUTTON_PRESS_MASK,
272                                     NULL, event->button.time);
273                 ret = TRUE;
274             }
275             break;
276         case GDK_MOTION_NOTIFY:
277             if (dragging && (event->motion.state & GDK_BUTTON1_MASK)) {
279                 if ( event_context->within_tolerance
280                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
281                      && ( abs( (gint) event->motion.y - event_context->yp ) < event_context->tolerance ) ) {
282                     break; // do not drag if we're within tolerance from origin
283                 }
284                 // Once the user has moved farther than tolerance from the original location
285                 // (indicating they intend to draw, not click), then always process the
286                 // motion notify coordinates as given (no snapping back to origin)
287                 event_context->within_tolerance = false;
289                 NR::Point const motion_w(event->motion.x, event->motion.y);
290                 NR::Point motion_dt(desktop->w2d(motion_w));
291                 
292                 SnapManager const &m = desktop->namedview->snap_manager;            
293                 motion_dt = m.freeSnap(Inkscape::Snapper::BBOX_POINT | Inkscape::Snapper::SNAP_POINT, motion_dt, ac->item).getPoint();
294             
295                 
296                 sp_arc_drag(ac, motion_dt, event->motion.state);
297                 ret = TRUE;
298             }
299             break;
300         case GDK_BUTTON_RELEASE:
301             event_context->xp = event_context->yp = 0;
302             if (event->button.button == 1) {
303                 dragging = false;
304                 if (!event_context->within_tolerance) {
305                     // we've been dragging, finish the arc
306                     sp_arc_finish(ac);
307                 } else if (event_context->item_to_select) {
308                     // no dragging, select clicked item if any
309                     if (event->button.state & GDK_SHIFT_MASK) {
310                         selection->toggle(event_context->item_to_select);
311                     } else {
312                         selection->set(event_context->item_to_select);
313                     }
314                 } else {
315                     // click in an empty space
316                     selection->clear();
317                 }
318                 event_context->xp = 0;
319                 event_context->yp = 0;
320                 event_context->item_to_select = NULL;
321                 ret = TRUE;
322             }
323             sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
324             break;
325         case GDK_KEY_PRESS:
326             switch (get_group0_keyval (&event->key)) {
327                 case GDK_Alt_L:
328                 case GDK_Alt_R:
329                 case GDK_Control_L:
330                 case GDK_Control_R:
331                 case GDK_Shift_L:
332                 case GDK_Shift_R:
333                 case GDK_Meta_L:  // Meta is when you press Shift+Alt (at least on my machine)
334                 case GDK_Meta_R:
335                     if (!dragging) {
336                         sp_event_show_modifier_tip(event_context->defaultMessageContext(), event,
337                                                    _("<b>Ctrl</b>: make circle or integer-ratio ellipse, snap arc/segment angle"),
338                                                    _("<b>Shift</b>: draw around the starting point"),
339                                                    NULL);
340                     }
341                     break;
342                 case GDK_Up:
343                 case GDK_Down:
344                 case GDK_KP_Up:
345                 case GDK_KP_Down:
346                     // prevent the zoom field from activation
347                     if (!MOD__CTRL_ONLY)
348                         ret = TRUE;
349                     break;
350                 case GDK_x:
351                 case GDK_X:
352                     if (MOD__ALT_ONLY) {
353                         desktop->setToolboxFocusTo ("altx-arc");
354                         ret = TRUE;
355                     }
356                     break;
357                 case GDK_Escape:
358                     sp_desktop_selection(desktop)->clear();
359                     //TODO: make dragging escapable by Esc
360                 default:
361                     break;
362             }
363             break;
364         case GDK_KEY_RELEASE:
365             switch (event->key.keyval) {
366                 case GDK_Alt_L:
367                 case GDK_Alt_R:
368                 case GDK_Control_L:
369                 case GDK_Control_R:
370                 case GDK_Shift_L:
371                 case GDK_Shift_R:
372                 case GDK_Meta_L:  // Meta is when you press Shift+Alt
373                 case GDK_Meta_R:
374                     event_context->defaultMessageContext()->clear();
375                     break;
376                 default:
377                     break;
378             }
379             break;
380         default:
381             break;
382     }
384     if (!ret) {
385         if (((SPEventContextClass *) parent_class)->root_handler) {
386             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
387         }
388     }
390     return ret;
393 static void sp_arc_drag(SPArcContext *ac, NR::Point pt, guint state)
395     SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
397     if (!ac->item) {
399         if (Inkscape::have_viable_layer(desktop, ac->_message_context) == false) {
400             return;
401         }
403         /* Create object */
404         Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
405         Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
406         repr->setAttribute("sodipodi:type", "arc");
408         /* Set style */
409         sp_desktop_apply_style_tool(desktop, repr, "tools.shapes.arc", false);
411         ac->item = SP_ITEM(desktop->currentLayer()->appendChildRepr(repr));
412         Inkscape::GC::release(repr);
413         ac->item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
414         ac->item->updateRepr();
416         sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 5);
417     }
419     NR::Rect const r = Inkscape::snap_rectangular_box(desktop, ac->item, pt, ac->center, state);
421     sp_arc_position_set(SP_ARC(ac->item),
422                         r.midpoint()[NR::X], r.midpoint()[NR::Y],
423                         r.dimensions()[NR::X] / 2, r.dimensions()[NR::Y] / 2);
425     GString *xs = SP_PX_TO_METRIC_STRING(r.dimensions()[NR::X], desktop->namedview->getDefaultMetric());
426     GString *ys = SP_PX_TO_METRIC_STRING(r.dimensions()[NR::Y], desktop->namedview->getDefaultMetric());
427     ac->_message_context->setF(Inkscape::NORMAL_MESSAGE, _("<b>Ellipse</b>: %s &#215; %s; with <b>Ctrl</b> to make circle or integer-ratio ellipse; with <b>Shift</b> to draw around the starting point"), xs->str, ys->str);
428     g_string_free(xs, FALSE);
429     g_string_free(ys, FALSE);
432 static void sp_arc_finish(SPArcContext *ac)
434     ac->_message_context->clear();
436     if (ac->item != NULL) {
437         SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
439         SP_OBJECT(ac->item)->updateRepr();
441         sp_canvas_end_forced_full_redraws(desktop->canvas);
442         
443         sp_desktop_selection(desktop)->set(ac->item);
444         sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ARC, 
445                          _("Create ellipse"));
447         ac->item = NULL;
448     }
452 /*
453   Local Variables:
454   mode:c++
455   c-file-style:"stroustrup"
456   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
457   indent-tabs-mode:nil
458   fill-column:99
459   End:
460 */
461 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :