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 #include "shape-editor.h"
  44 #include "event-context.h"
  45
  46 #include "arc-context.h"
  47
  48 static void sp_arc_context_class_init(SPArcContextClass *klass);
  49 static void sp_arc_context_init(SPArcContext *arc_context);
  50 static void sp_arc_context_dispose(GObject *object);
  51
  52 static void sp_arc_context_setup(SPEventContext *ec);
  53 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event);
  54 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event);
  55
  56 static void sp_arc_drag(SPArcContext *ec, Geom::Point pt, guint state);
  57 static void sp_arc_finish(SPArcContext *ec);
  58
  59 static SPEventContextClass *parent_class;
  60
  61 GtkType sp_arc_context_get_type()
  62 {
  63     static GType type = 0;
  64     if (!type) {
  65         GTypeInfo info = {
  66             sizeof(SPArcContextClass),
  67             NULL, NULL,
  68             (GClassInitFunc) sp_arc_context_class_init,
  69             NULL, NULL,
  70             sizeof(SPArcContext),
  71             4,
  72             (GInstanceInitFunc) sp_arc_context_init,
  73             NULL,   /* value_table */
  74         };
  75         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPArcContext", &info, (GTypeFlags) 0);
  76     }
  77     return type;
  78 }
  79
  80 static void sp_arc_context_class_init(SPArcContextClass *klass)
  81 {
  82
  83     GObjectClass *object_class = (GObjectClass *) klass;
  84     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
  85
  86     parent_class = (SPEventContextClass*) g_type_class_peek_parent(klass);
  87
  88     object_class->dispose = sp_arc_context_dispose;
  89
  90     event_context_class->setup = sp_arc_context_setup;
  91     event_context_class->root_handler = sp_arc_context_root_handler;
  92     event_context_class->item_handler = sp_arc_context_item_handler;
  93 }
  94
  95 static void sp_arc_context_init(SPArcContext *arc_context)
  96 {
  97     SPEventContext *event_context = SP_EVENT_CONTEXT(arc_context);
  98
  99     event_context->cursor_shape = cursor_ellipse_xpm;
 100     event_context->hot_x = 4;
 101     event_context->hot_y = 4;
 102     event_context->xp = 0;
 103     event_context->yp = 0;
 104     event_context->tolerance = 0;
 105     event_context->within_tolerance = false;
 106     event_context->item_to_select = NULL;
 107
 108     arc_context->item = NULL;
 109
 110     new (&arc_context->sel_changed_connection) sigc::connection();
 111 }
 112
 113 static void sp_arc_context_dispose(GObject *object)
 114 {
 115     SPEventContext *ec = SP_EVENT_CONTEXT(object);
 116     SPArcContext *ac = SP_ARC_CONTEXT(object);
 117
 118     ec->enableGrDrag(false);
 119
 120     ac->sel_changed_connection.disconnect();
 121     ac->sel_changed_connection.~connection();
 122
 123     delete ec->shape_editor;
 124     ec->shape_editor = NULL;
 125
 126     /* fixme: This is necessary because we do not grab */
 127     if (ac->item) {
 128         sp_arc_finish(ac);
 129     }
 130
 131     delete ac->_message_context;
 132
 133     G_OBJECT_CLASS(parent_class)->dispose(object);
 134 }
 135
 136 /**
 137 \brief  Callback that processes the "changed" signal on the selection;
 138 destroys old and creates new knotholder.
 139 */
 140 void sp_arc_context_selection_changed(Inkscape::Selection * selection, gpointer data)
 141 {
 142     SPArcContext *ac = SP_ARC_CONTEXT(data);
 143     SPEventContext *ec = SP_EVENT_CONTEXT(ac);
 144
 145     ec->shape_editor->unset_item(SH_KNOTHOLDER);
 146     SPItem *item = selection->singleItem();
 147     ec->shape_editor->set_item(item, SH_KNOTHOLDER);
 148 }
 149
 150 static void sp_arc_context_setup(SPEventContext *ec)
 151 {
 152     SPArcContext *ac = SP_ARC_CONTEXT(ec);
 153     Inkscape::Selection *selection = sp_desktop_selection(ec->desktop);
 154
 155     if (((SPEventContextClass *) parent_class)->setup) {
 156         ((SPEventContextClass *) parent_class)->setup(ec);
 157     }
 158
 159     ec->shape_editor = new ShapeEditor(ec->desktop);
 160
 161     SPItem *item = sp_desktop_selection(ec->desktop)->singleItem();
 162     if (item) {
 163         ec->shape_editor->set_item(item, SH_KNOTHOLDER);
 164     }
 165
 166     ac->sel_changed_connection.disconnect();
 167     ac->sel_changed_connection = selection->connectChanged(
 168         sigc::bind(sigc::ptr_fun(&sp_arc_context_selection_changed), (gpointer) ac)
 169         );
 170
 171     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 172     if (prefs->getBool("/tools/shapes/selcue")) {
 173         ec->enableSelectionCue();
 174     }
 175
 176     if (prefs->getBool("/tools/shapes/gradientdrag")) {
 177         ec->enableGrDrag();
 178     }
 179
 180     ac->_message_context = new Inkscape::MessageContext(ec->desktop->messageStack());
 181 }
 182
 183 static gint sp_arc_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event)
 184 {
 185     SPDesktop *desktop = event_context->desktop;
 186     gint ret = FALSE;
 187
 188     switch (event->type) {
 189         case GDK_BUTTON_PRESS:
 190             if (event->button.button == 1 && !event_context->space_panning) {
 191                 Inkscape::setup_for_drag_start(desktop, event_context, event);
 192                 ret = TRUE;
 193             }
 194             break;
 195             // motion and release are always on root (why?)
 196         default:
 197             break;
 198     }
 199
 200     if (((SPEventContextClass *) parent_class)->item_handler) {
 201         ret = ((SPEventContextClass *) parent_class)->item_handler(event_context, item, event);
 202     }
 203
 204     return ret;
 205 }
 206
 207 static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent *event)
 208 {
 209     static bool dragging;
 210
 211     SPDesktop *desktop = event_context->desktop;
 212     Inkscape::Selection *selection = sp_desktop_selection(desktop);
 213     SPArcContext *ac = SP_ARC_CONTEXT(event_context);
 214     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 215
 216     event_context->tolerance = prefs->getIntLimited("/options/dragtolerance/value", 0, 0, 100);
 217
 218     gint ret = FALSE;
 219
 220     switch (event->type) {
 221         case GDK_BUTTON_PRESS:
 222             if (event->button.button == 1 && !event_context->space_panning) {
 223
 224                 dragging = true;
 225                 sp_event_context_snap_window_open(event_context);
 226                 ac->center = Inkscape::setup_for_drag_start(desktop, event_context, event);
 227
 228                 /* Snap center */
 229                 SnapManager &m = desktop->namedview->snap_manager;
 230                 m.setup(desktop);
 231                 Geom::Point pt2g = to_2geom(ac->center);
 232                 m.freeSnapReturnByRef(Inkscape::SnapPreferences::SNAPPOINT_NODE, pt2g, Inkscape::SNAPSOURCE_HANDLE);
 233                 ac->center = from_2geom(pt2g);
 234
 235                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
 236                                     GDK_KEY_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
 237                                     GDK_POINTER_MOTION_MASK | GDK_POINTER_MOTION_HINT_MASK | GDK_BUTTON_PRESS_MASK,
 238                                     NULL, event->button.time);
 239                 ret = TRUE;
 240             }
 241             break;
 242         case GDK_MOTION_NOTIFY:
 243             if (dragging && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {
 244
 245                 if ( event_context->within_tolerance
 246                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
 247                      && ( abs( (gint) event->motion.y - event_context->yp ) < event_context->tolerance ) ) {
 248                     break; // do not drag if we're within tolerance from origin
 249                 }
 250                 // Once the user has moved farther than tolerance from the original location
 251                 // (indicating they intend to draw, not click), then always process the
 252                 // motion notify coordinates as given (no snapping back to origin)
 253                 event_context->within_tolerance = false;
 254
 255                 Geom::Point const motion_w(event->motion.x, event->motion.y);
 256                 Geom::Point motion_dt(desktop->w2d(motion_w));
 257
 258                 sp_arc_drag(ac, motion_dt, event->motion.state);
 259
 260                 gobble_motion_events(GDK_BUTTON1_MASK);
 261
 262                 ret = TRUE;
 263             }
 264             break;
 265         case GDK_BUTTON_RELEASE:
 266             event_context->xp = event_context->yp = 0;
 267             if (event->button.button == 1 && !event_context->space_panning) {
 268                 dragging = false;
 269                 sp_event_context_snap_window_closed(event_context, false); //button release will also occur on a double-click; in that case suppress warnings
 270                 if (!event_context->within_tolerance) {
 271                     // we've been dragging, finish the arc
 272                     sp_arc_finish(ac);
 273                 } else if (event_context->item_to_select) {
 274                     // no dragging, select clicked item if any
 275                     if (event->button.state & GDK_SHIFT_MASK) {
 276                         selection->toggle(event_context->item_to_select);
 277                     } else {
 278                         selection->set(event_context->item_to_select);
 279                     }
 280                 } else {
 281                     // click in an empty space
 282                     selection->clear();
 283                 }
 284                 event_context->xp = 0;
 285                 event_context->yp = 0;
 286                 event_context->item_to_select = NULL;
 287                 ret = TRUE;
 288             }
 289             sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
 290             break;
 291         case GDK_KEY_PRESS:
 292             switch (get_group0_keyval (&event->key)) {
 293                 case GDK_Alt_L:
 294                 case GDK_Alt_R:
 295                 case GDK_Control_L:
 296                 case GDK_Control_R:
 297                 case GDK_Shift_L:
 298                 case GDK_Shift_R:
 299                 case GDK_Meta_L:  // Meta is when you press Shift+Alt (at least on my machine)
 300                 case GDK_Meta_R:
 301                     if (!dragging) {
 302                         sp_event_show_modifier_tip(event_context->defaultMessageContext(), event,
 303                                                    _("<b>Ctrl</b>: make circle or integer-ratio ellipse, snap arc/segment angle"),
 304                                                    _("<b>Shift</b>: draw around the starting point"),
 305                                                    NULL);
 306                     }
 307                     break;
 308                 case GDK_Up:
 309                 case GDK_Down:
 310                 case GDK_KP_Up:
 311                 case GDK_KP_Down:
 312                     // prevent the zoom field from activation
 313                     if (!MOD__CTRL_ONLY)
 314                         ret = TRUE;
 315                     break;
 316                 case GDK_x:
 317                 case GDK_X:
 318                     if (MOD__ALT_ONLY) {
 319                         desktop->setToolboxFocusTo ("altx-arc");
 320                         ret = TRUE;
 321                     }
 322                     break;
 323                 case GDK_Escape:
 324                     sp_desktop_selection(desktop)->clear();
 325                     //TODO: make dragging escapable by Esc
 326                     break;
 327
 328                 case GDK_space:
 329                     if (dragging) {
 330                         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate),
 331                                               event->button.time);
 332                         dragging = false;
 333                         sp_event_context_snap_window_closed(event_context);
 334                         if (!event_context->within_tolerance) {
 335                             // we've been dragging, finish the rect
 336                             sp_arc_finish(ac);
 337                         }
 338                         // do not return true, so that space would work switching to selector
 339                     }
 340                     break;
 341
 342                 default:
 343                     break;
 344             }
 345             break;
 346         case GDK_KEY_RELEASE:
 347             switch (event->key.keyval) {
 348                 case GDK_Alt_L:
 349                 case GDK_Alt_R:
 350                 case GDK_Control_L:
 351                 case GDK_Control_R:
 352                 case GDK_Shift_L:
 353                 case GDK_Shift_R:
 354                 case GDK_Meta_L:  // Meta is when you press Shift+Alt
 355                 case GDK_Meta_R:
 356                     event_context->defaultMessageContext()->clear();
 357                     break;
 358                 default:
 359                     break;
 360             }
 361             break;
 362         default:
 363             break;
 364     }
 365
 366     if (!ret) {
 367         if (((SPEventContextClass *) parent_class)->root_handler) {
 368             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
 369         }
 370     }
 371
 372     return ret;
 373 }
 374
 375 static void sp_arc_drag(SPArcContext *ac, Geom::Point pt, guint state)
 376 {
 377     SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 378
 379     if (!ac->item) {
 380
 381         if (Inkscape::have_viable_layer(desktop, ac->_message_context) == false) {
 382             return;
 383         }
 384
 385         /* Create object */
 386         Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
 387         Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
 388         repr->setAttribute("sodipodi:type", "arc");
 389
 390         /* Set style */
 391         sp_desktop_apply_style_tool(desktop, repr, "/tools/shapes/arc", false);
 392
 393         ac->item = SP_ITEM(desktop->currentLayer()->appendChildRepr(repr));
 394         Inkscape::GC::release(repr);
 395         ac->item->transform = sp_item_i2doc_affine(SP_ITEM(desktop->currentLayer())).inverse();
 396         ac->item->updateRepr();
 397
 398         sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 5);
 399     }
 400
 401     bool ctrl_save = false;
 402     if ((state & GDK_MOD1_MASK) && (state & GDK_CONTROL_MASK) && !(state & GDK_SHIFT_MASK)) {
 403         // if Alt is pressed without Shift in addition to Control, temporarily drop the CONTROL mask
 404         // so that the ellipse is not constrained to integer ratios
 405         ctrl_save = true;
 406         state = state ^ GDK_CONTROL_MASK;
 407     }
 408     Geom::Rect r = Inkscape::snap_rectangular_box(desktop, ac->item, pt, ac->center, state);
 409     if (ctrl_save) {
 410         state = state ^ GDK_CONTROL_MASK;
 411     }
 412
 413     Geom::Point dir = r.dimensions() / 2;
 414     if (state & GDK_MOD1_MASK) {
 415         /* With Alt let the ellipse pass through the mouse pointer */
 416         Geom::Point c = r.midpoint();
 417         if (!ctrl_save) {
 418             if (fabs(dir[Geom::X]) > 1E-6 && fabs(dir[Geom::Y]) > 1E-6) {
 419                 Geom::Matrix const i2d (sp_item_i2d_affine (ac->item));
 420                 Geom::Point new_dir = pt * i2d - c;
 421                 new_dir[Geom::X] *= dir[Geom::Y] / dir[Geom::X];
 422                 double lambda = new_dir.length() / dir[Geom::Y];
 423                 r = Geom::Rect (c - lambda*dir, c + lambda*dir);
 424             }
 425         } else {
 426             /* with Alt+Ctrl (without Shift) we generate a perfect circle
 427                with diameter click point <--> mouse pointer */
 428                 double l = dir.length();
 429                 Geom::Point d (l, l);
 430                 r = Geom::Rect (c - d, c + d);
 431         }
 432     }
 433
 434     sp_arc_position_set(SP_ARC(ac->item),
 435                         r.midpoint()[Geom::X], r.midpoint()[Geom::Y],
 436                         r.dimensions()[Geom::X] / 2, r.dimensions()[Geom::Y] / 2);
 437
 438     double rdimx = r.dimensions()[Geom::X];
 439     double rdimy = r.dimensions()[Geom::Y];
 440     GString *xs = SP_PX_TO_METRIC_STRING(rdimx, desktop->namedview->getDefaultMetric());
 441     GString *ys = SP_PX_TO_METRIC_STRING(rdimy, desktop->namedview->getDefaultMetric());
 442     if (state & GDK_CONTROL_MASK) {
 443         int ratio_x, ratio_y;
 444         if (fabs (rdimx) > fabs (rdimy)) {
 445             ratio_x = (int) rint (rdimx / rdimy);
 446             ratio_y = 1;
 447         } else {
 448             ratio_x = 1;
 449             ratio_y = (int) rint (rdimy / rdimx);
 450         }
 451         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);
 452     } else {
 453         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);
 454     }
 455     g_string_free(xs, FALSE);
 456     g_string_free(ys, FALSE);
 457 }
 458
 459 static void sp_arc_finish(SPArcContext *ac)
 460 {
 461     ac->_message_context->clear();
 462
 463     if (ac->item != NULL) {
 464         SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 465
 466         SP_OBJECT(ac->item)->updateRepr();
 467
 468         sp_canvas_end_forced_full_redraws(desktop->canvas);
 469
 470         sp_desktop_selection(desktop)->set(ac->item);
 471         sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ARC,
 472                          _("Create ellipse"));
 473
 474         ac->item = NULL;
 475     }
 476 }
 477
 478
 479 /*
 480   Local Variables:
 481   mode:c++
 482   c-file-style:"stroustrup"
 483   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 484   indent-tabs-mode:nil
 485   fill-column:99
 486   End:
 487 */
 488 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :