src/arc-context.cpp

   1 /** @file
   2  * @brief Ellipse drawing context
   3  */
   4 /* Authors:
   5  *   Mitsuru Oka
   6  *   Lauris Kaplinski <lauris@kaplinski.com>
   7  *   bulia byak <buliabyak@users.sf.net>
   8  *   Johan Engelen <johan@shouraizou.nl>
   9  *
  10  * Copyright (C) 2000-2006 Authors
  11  * Copyright (C) 2000-2001 Ximian, Inc.
  12  *
  13  * Released under GNU GPL, read the file 'COPYING' for more information
  14  */
  15
  16 #define __SP_ARC_CONTEXT_C__
  17
  18 #ifdef HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21 #include <gdk/gdkkeysyms.h>
  22
  23 #include "macros.h"
  24 #include <glibmm/i18n.h>
  25 #include "display/sp-canvas.h"
  26 #include "sp-ellipse.h"
  27 #include "document.h"
  28 #include "sp-namedview.h"
  29 #include "selection.h"
  30 #include "desktop-handles.h"
  31 #include "snap.h"
  32 #include "pixmaps/cursor-ellipse.xpm"
  33 #include "sp-metrics.h"
  34 #include "xml/repr.h"
  35 #include "xml/node-event-vector.h"
  36 #include "object-edit.h"
  37 #include "preferences.h"
  38 #include "message-context.h"
  39 #include "desktop.h"
  40 #include "desktop-style.h"
  41 #include "context-fns.h"
  42 #include "verbs.h"
  43
  44 #include "arc-context.h"
  45
  46 static void sp_arc_context_class_init(SPArcContextClass *klass);
  47 static void sp_arc_context_init(SPArcContext *arc_context);
  48 static void sp_arc_context_dispose(GObject *object);
  49
  50 static void sp_arc_context_setup(SPEventContext *ec);
  51 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event);
  52 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event);
  53
  54 static void sp_arc_drag(SPArcContext *ec, Geom::Point pt, guint state);
  55 static void sp_arc_finish(SPArcContext *ec);
  56
  57 static SPEventContextClass *parent_class;
  58
  59 GtkType sp_arc_context_get_type()
  60 {
  61     static GType type = 0;
  62     if (!type) {
  63         GTypeInfo info = {
  64             sizeof(SPArcContextClass),
  65             NULL, NULL,
  66             (GClassInitFunc) sp_arc_context_class_init,
  67             NULL, NULL,
  68             sizeof(SPArcContext),
  69             4,
  70             (GInstanceInitFunc) sp_arc_context_init,
  71             NULL,   /* value_table */
  72         };
  73         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPArcContext", &info, (GTypeFlags) 0);
  74     }
  75     return type;
  76 }
  77
  78 static void sp_arc_context_class_init(SPArcContextClass *klass)
  79 {
  80
  81     GObjectClass *object_class = (GObjectClass *) klass;
  82     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
  83
  84     parent_class = (SPEventContextClass*) g_type_class_peek_parent(klass);
  85
  86     object_class->dispose = sp_arc_context_dispose;
  87
  88     event_context_class->setup = sp_arc_context_setup;
  89     event_context_class->root_handler = sp_arc_context_root_handler;
  90     event_context_class->item_handler = sp_arc_context_item_handler;
  91 }
  92
  93 static void sp_arc_context_init(SPArcContext *arc_context)
  94 {
  95     SPEventContext *event_context = SP_EVENT_CONTEXT(arc_context);
  96
  97     event_context->cursor_shape = cursor_ellipse_xpm;
  98     event_context->hot_x = 4;
  99     event_context->hot_y = 4;
 100     event_context->xp = 0;
 101     event_context->yp = 0;
 102     event_context->tolerance = 0;
 103     event_context->within_tolerance = false;
 104     event_context->item_to_select = NULL;
 105
 106     event_context->shape_repr = NULL;
 107     event_context->shape_knot_holder = NULL;
 108
 109     arc_context->item = NULL;
 110
 111     new (&arc_context->sel_changed_connection) sigc::connection();
 112 }
 113
 114 static void sp_arc_context_dispose(GObject *object)
 115 {
 116     SPEventContext *ec = SP_EVENT_CONTEXT(object);
 117     SPArcContext *ac = SP_ARC_CONTEXT(object);
 118
 119     ec->enableGrDrag(false);
 120
 121     ac->sel_changed_connection.disconnect();
 122     ac->sel_changed_connection.~connection();
 123
 124     if (ec->shape_knot_holder) {
 125         delete ec->shape_knot_holder;
 126         ec->shape_knot_holder = NULL;
 127     }
 128
 129     if (ec->shape_repr) { // remove old listener
 130         sp_repr_remove_listener_by_data(ec->shape_repr, ec);
 131         Inkscape::GC::release(ec->shape_repr);
 132         ec->shape_repr = 0;
 133     }
 134
 135     /* fixme: This is necessary because we do not grab */
 136     if (ac->item) {
 137         sp_arc_finish(ac);
 138     }
 139
 140     delete ac->_message_context;
 141
 142     G_OBJECT_CLASS(parent_class)->dispose(object);
 143 }
 144
 145 static Inkscape::XML::NodeEventVector ec_shape_repr_events = {
 146     NULL, /* child_added */
 147     NULL, /* child_removed */
 148     ec_shape_event_attr_changed,
 149     NULL, /* content_changed */
 150     NULL  /* order_changed */
 151 };
 152
 153 /**
 154 \brief  Callback that processes the "changed" signal on the selection;
 155 destroys old and creates new knotholder.
 156 */
 157 void sp_arc_context_selection_changed(Inkscape::Selection * selection, gpointer data)
 158 {
 159     SPArcContext *ac = SP_ARC_CONTEXT(data);
 160     SPEventContext *ec = SP_EVENT_CONTEXT(ac);
 161
 162     if (ec->shape_knot_holder) { // desktroy knotholder
 163         delete ec->shape_knot_holder;
 164         ec->shape_knot_holder = NULL;
 165     }
 166
 167     if (ec->shape_repr) { // remove old listener
 168         sp_repr_remove_listener_by_data(ec->shape_repr, ec);
 169         Inkscape::GC::release(ec->shape_repr);
 170         ec->shape_repr = 0;
 171     }
 172
 173     SPItem *item = selection ? selection->singleItem() : NULL;
 174     if (item) {
 175         ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
 176         Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
 177         if (shape_repr) {
 178             ec->shape_repr = shape_repr;
 179             Inkscape::GC::anchor(shape_repr);
 180             sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
 181         }
 182     }
 183 }
 184
 185 static void sp_arc_context_setup(SPEventContext *ec)
 186 {
 187     SPArcContext *ac = SP_ARC_CONTEXT(ec);
 188     Inkscape::Selection *selection = sp_desktop_selection(ec->desktop);
 189
 190     if (((SPEventContextClass *) parent_class)->setup) {
 191         ((SPEventContextClass *) parent_class)->setup(ec);
 192     }
 193
 194     SPItem *item = selection->singleItem();
 195
 196     if (item) {
 197         ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
 198         Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
 199         if (shape_repr) {
 200             ec->shape_repr = shape_repr;
 201             Inkscape::GC::anchor(shape_repr);
 202             sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
 203         }
 204     }
 205
 206     ac->sel_changed_connection.disconnect();
 207     ac->sel_changed_connection = selection->connectChanged(
 208         sigc::bind(sigc::ptr_fun(&sp_arc_context_selection_changed), (gpointer) ac)
 209         );
 210
 211     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 212     if (prefs->getBool("/tools/shapes/selcue")) {
 213         ec->enableSelectionCue();
 214     }
 215
 216     if (prefs->getBool("/tools/shapes/gradientdrag")) {
 217         ec->enableGrDrag();
 218     }
 219
 220     ac->_message_context = new Inkscape::MessageContext(ec->desktop->messageStack());
 221 }
 222
 223 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event)
 224 {
 225     SPDesktop *desktop = event_context->desktop;
 226     gint ret = FALSE;
 227
 228     switch (event->type) {
 229         case GDK_BUTTON_PRESS:
 230             if (event->button.button == 1 && !event_context->space_panning) {
 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     }
 239
 240     if (((SPEventContextClass *) parent_class)->item_handler) {
 241         ret = ((SPEventContextClass *) parent_class)->item_handler(event_context, item, event);
 242     }
 243
 244     return ret;
 245 }
 246
 247 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event)
 248 {
 249     static bool dragging;
 250
 251     SPDesktop *desktop = event_context->desktop;
 252     Inkscape::Selection *selection = sp_desktop_selection(desktop);
 253     SPArcContext *ac = SP_ARC_CONTEXT(event_context);
 254     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 255
 256     event_context->tolerance = prefs->getIntLimited("/options/dragtolerance/value", 0, 0, 100);
 257
 258     gint ret = FALSE;
 259
 260     switch (event->type) {
 261         case GDK_BUTTON_PRESS:
 262             if (event->button.button == 1 && !event_context->space_panning) {
 263
 264                 dragging = true;
 265                 ac->center = Inkscape::setup_for_drag_start(desktop, event_context, event);
 266
 267                 /* Snap center */
 268                 SnapManager &m = desktop->namedview->snap_manager;
 269                 m.setup(desktop);
 270                 Geom::Point pt2g = to_2geom(ac->center);
 271                 m.freeSnapReturnByRef(Inkscape::SnapPreferences::SNAPPOINT_NODE, pt2g);
 272                 ac->center = from_2geom(pt2g);
 273
 274                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
 275                                     GDK_KEY_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
 276                                     GDK_POINTER_MOTION_MASK | GDK_POINTER_MOTION_HINT_MASK | GDK_BUTTON_PRESS_MASK,
 277                                     NULL, event->button.time);
 278                 ret = TRUE;
 279             }
 280             break;
 281         case GDK_MOTION_NOTIFY:
 282             if (dragging && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {
 283
 284                 if ( event_context->within_tolerance
 285                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
 286                      && ( abs( (gint) event->motion.y - event_context->yp ) < event_context->tolerance ) ) {
 287                     break; // do not drag if we're within tolerance from origin
 288                 }
 289                 // Once the user has moved farther than tolerance from the original location
 290                 // (indicating they intend to draw, not click), then always process the
 291                 // motion notify coordinates as given (no snapping back to origin)
 292                 event_context->within_tolerance = false;
 293
 294                 Geom::Point const motion_w(event->motion.x, event->motion.y);
 295                 Geom::Point motion_dt(desktop->w2d(motion_w));
 296
 297                 sp_arc_drag(ac, motion_dt, event->motion.state);
 298
 299                 gobble_motion_events(GDK_BUTTON1_MASK);
 300
 301                 ret = TRUE;
 302             }
 303             break;
 304         case GDK_BUTTON_RELEASE:
 305             event_context->xp = event_context->yp = 0;
 306             if (event->button.button == 1 && !event_context->space_panning) {
 307                 dragging = false;
 308                 if (!event_context->within_tolerance) {
 309                     // we've been dragging, finish the arc
 310                     sp_arc_finish(ac);
 311                 } else if (event_context->item_to_select) {
 312                     // no dragging, select clicked item if any
 313                     if (event->button.state & GDK_SHIFT_MASK) {
 314                         selection->toggle(event_context->item_to_select);
 315                     } else {
 316                         selection->set(event_context->item_to_select);
 317                     }
 318                 } else {
 319                     // click in an empty space
 320                     selection->clear();
 321                 }
 322                 event_context->xp = 0;
 323                 event_context->yp = 0;
 324                 event_context->item_to_select = NULL;
 325                 ret = TRUE;
 326             }
 327             sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
 328             break;
 329         case GDK_KEY_PRESS:
 330             switch (get_group0_keyval (&event->key)) {
 331                 case GDK_Alt_L:
 332                 case GDK_Alt_R:
 333                 case GDK_Control_L:
 334                 case GDK_Control_R:
 335                 case GDK_Shift_L:
 336                 case GDK_Shift_R:
 337                 case GDK_Meta_L:  // Meta is when you press Shift+Alt (at least on my machine)
 338                 case GDK_Meta_R:
 339                     if (!dragging) {
 340                         sp_event_show_modifier_tip(event_context->defaultMessageContext(), event,
 341                                                    _("<b>Ctrl</b>: make circle or integer-ratio ellipse, snap arc/segment angle"),
 342                                                    _("<b>Shift</b>: draw around the starting point"),
 343                                                    NULL);
 344                     }
 345                     break;
 346                 case GDK_Up:
 347                 case GDK_Down:
 348                 case GDK_KP_Up:
 349                 case GDK_KP_Down:
 350                     // prevent the zoom field from activation
 351                     if (!MOD__CTRL_ONLY)
 352                         ret = TRUE;
 353                     break;
 354                 case GDK_x:
 355                 case GDK_X:
 356                     if (MOD__ALT_ONLY) {
 357                         desktop->setToolboxFocusTo ("altx-arc");
 358                         ret = TRUE;
 359                     }
 360                     break;
 361                 case GDK_Escape:
 362                     sp_desktop_selection(desktop)->clear();
 363                     //TODO: make dragging escapable by Esc
 364                     break;
 365
 366                 case GDK_space:
 367                     if (dragging) {
 368                         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate),
 369                                               event->button.time);
 370                         dragging = false;
 371                         if (!event_context->within_tolerance) {
 372                             // we've been dragging, finish the rect
 373                             sp_arc_finish(ac);
 374                         }
 375                         // do not return true, so that space would work switching to selector
 376                     }
 377                     break;
 378
 379                 default:
 380                     break;
 381             }
 382             break;
 383         case GDK_KEY_RELEASE:
 384             switch (event->key.keyval) {
 385                 case GDK_Alt_L:
 386                 case GDK_Alt_R:
 387                 case GDK_Control_L:
 388                 case GDK_Control_R:
 389                 case GDK_Shift_L:
 390                 case GDK_Shift_R:
 391                 case GDK_Meta_L:  // Meta is when you press Shift+Alt
 392                 case GDK_Meta_R:
 393                     event_context->defaultMessageContext()->clear();
 394                     break;
 395                 default:
 396                     break;
 397             }
 398             break;
 399         default:
 400             break;
 401     }
 402
 403     if (!ret) {
 404         if (((SPEventContextClass *) parent_class)->root_handler) {
 405             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
 406         }
 407     }
 408
 409     return ret;
 410 }
 411
 412 static void sp_arc_drag(SPArcContext *ac, Geom::Point pt, guint state)
 413 {
 414     SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 415
 416     if (!ac->item) {
 417
 418         if (Inkscape::have_viable_layer(desktop, ac->_message_context) == false) {
 419             return;
 420         }
 421
 422         /* Create object */
 423         Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
 424         Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
 425         repr->setAttribute("sodipodi:type", "arc");
 426
 427         /* Set style */
 428         sp_desktop_apply_style_tool(desktop, repr, "/tools/shapes/arc", false);
 429
 430         ac->item = SP_ITEM(desktop->currentLayer()->appendChildRepr(repr));
 431         Inkscape::GC::release(repr);
 432         ac->item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
 433         ac->item->updateRepr();
 434
 435         sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 5);
 436     }
 437
 438     bool ctrl_save = false;
 439     if ((state & GDK_MOD1_MASK) && (state & GDK_CONTROL_MASK) && !(state & GDK_SHIFT_MASK)) {
 440         // if Alt is pressed without Shift in addition to Control, temporarily drop the CONTROL mask
 441         // so that the ellipse is not constrained to integer ratios
 442         ctrl_save = true;
 443         state = state ^ GDK_CONTROL_MASK;
 444     }
 445     Geom::Rect r = Inkscape::snap_rectangular_box(desktop, ac->item, pt, ac->center, state);
 446     if (ctrl_save) {
 447         state = state ^ GDK_CONTROL_MASK;
 448     }
 449
 450     Geom::Point dir = r.dimensions() / 2;
 451     if (state & GDK_MOD1_MASK) {
 452         /* With Alt let the ellipse pass through the mouse pointer */
 453         Geom::Point c = r.midpoint();
 454         if (!ctrl_save) {
 455             if (fabs(dir[Geom::X]) > 1E-6 && fabs(dir[Geom::Y]) > 1E-6) {
 456                 Geom::Matrix const i2d (sp_item_i2d_affine (ac->item));
 457                 Geom::Point new_dir = pt * i2d - c;
 458                 new_dir[Geom::X] *= dir[Geom::Y] / dir[Geom::X];
 459                 double lambda = new_dir.length() / dir[Geom::Y];
 460                 r = Geom::Rect (c - lambda*dir, c + lambda*dir);
 461             }
 462         } else {
 463             /* with Alt+Ctrl (without Shift) we generate a perfect circle
 464                with diameter click point <--> mouse pointer */
 465                 double l = dir.length();
 466                 Geom::Point d (l, l);
 467                 r = Geom::Rect (c - d, c + d);
 468         }
 469     }
 470
 471     sp_arc_position_set(SP_ARC(ac->item),
 472                         r.midpoint()[Geom::X], r.midpoint()[Geom::Y],
 473                         r.dimensions()[Geom::X] / 2, r.dimensions()[Geom::Y] / 2);
 474
 475     double rdimx = r.dimensions()[Geom::X];
 476     double rdimy = r.dimensions()[Geom::Y];
 477     GString *xs = SP_PX_TO_METRIC_STRING(rdimx, desktop->namedview->getDefaultMetric());
 478     GString *ys = SP_PX_TO_METRIC_STRING(rdimy, desktop->namedview->getDefaultMetric());
 479     if (state & GDK_CONTROL_MASK) {
 480         int ratio_x, ratio_y;
 481         if (fabs (rdimx) > fabs (rdimy)) {
 482             ratio_x = (int) rint (rdimx / rdimy);
 483             ratio_y = 1;
 484         } else {
 485             ratio_x = 1;
 486             ratio_y = (int) rint (rdimy / rdimx);
 487         }
 488         ac->_message_context->setF(Inkscape::IMMEDIATE_MESSAGE, _("<b>Ellipse</b>: %s &#215; %s (constrained to ratio %d:%d); with <b>Shift</b> to draw around the starting point"), xs->str, ys->str, ratio_x, ratio_y);
 489     } else {
 490         ac->_message_context->setF(Inkscape::IMMEDIATE_MESSAGE, _("<b>Ellipse</b>: %s &#215; %s; with <b>Ctrl</b> to make square or integer-ratio ellipse; with <b>Shift</b> to draw around the starting point"), xs->str, ys->str);
 491     }
 492     g_string_free(xs, FALSE);
 493     g_string_free(ys, FALSE);
 494 }
 495
 496 static void sp_arc_finish(SPArcContext *ac)
 497 {
 498     ac->_message_context->clear();
 499
 500     if (ac->item != NULL) {
 501         SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 502
 503         SP_OBJECT(ac->item)->updateRepr();
 504
 505         sp_canvas_end_forced_full_redraws(desktop->canvas);
 506
 507         sp_desktop_selection(desktop)->set(ac->item);
 508         sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ARC,
 509                          _("Create ellipse"));
 510
 511         ac->item = NULL;
 512     }
 513 }
 514
 515
 516 /*
 517   Local Variables:
 518   mode:c++
 519   c-file-style:"stroustrup"
 520   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 521   indent-tabs-mode:nil
 522   fill-column:99
 523   End:
 524 */
 525 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :