src/arc-context.cpp

   1 #define __SP_ARC_CONTEXT_C__
   2
   3 /** \file Ellipse drawing context. */
   4
   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  */
  18
  19 #ifdef HAVE_CONFIG_H
  20 # include <config.h>
  21 #endif
  22 #include <gdk/gdkkeysyms.h>
  23
  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"
  44
  45 #include "arc-context.h"
  46
  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);
  50
  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);
  54
  55 static void sp_arc_drag(SPArcContext *ec, Geom::Point pt, guint state);
  56 static void sp_arc_finish(SPArcContext *ec);
  57
  58 static SPEventContextClass *parent_class;
  59
  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 }
  78
  79 static void sp_arc_context_class_init(SPArcContextClass *klass)
  80 {
  81
  82     GObjectClass *object_class = (GObjectClass *) klass;
  83     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
  84
  85     parent_class = (SPEventContextClass*) g_type_class_peek_parent(klass);
  86
  87     object_class->dispose = sp_arc_context_dispose;
  88
  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 }
  93
  94 static void sp_arc_context_init(SPArcContext *arc_context)
  95 {
  96     SPEventContext *event_context = SP_EVENT_CONTEXT(arc_context);
  97
  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;
 106
 107     event_context->shape_repr = NULL;
 108     event_context->shape_knot_holder = NULL;
 109
 110     arc_context->item = NULL;
 111
 112     new (&arc_context->sel_changed_connection) sigc::connection();
 113 }
 114
 115 static void sp_arc_context_dispose(GObject *object)
 116 {
 117     SPEventContext *ec = SP_EVENT_CONTEXT(object);
 118     SPArcContext *ac = SP_ARC_CONTEXT(object);
 119
 120     ec->enableGrDrag(false);
 121
 122     ac->sel_changed_connection.disconnect();
 123     ac->sel_changed_connection.~connection();
 124
 125     if (ec->shape_knot_holder) {
 126         delete ec->shape_knot_holder;
 127         ec->shape_knot_holder = NULL;
 128     }
 129
 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     }
 135
 136     /* fixme: This is necessary because we do not grab */
 137     if (ac->item) {
 138         sp_arc_finish(ac);
 139     }
 140
 141     delete ac->_message_context;
 142
 143     G_OBJECT_CLASS(parent_class)->dispose(object);
 144 }
 145
 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 };
 153
 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)
 159 {
 160     SPArcContext *ac = SP_ARC_CONTEXT(data);
 161     SPEventContext *ec = SP_EVENT_CONTEXT(ac);
 162
 163     if (ec->shape_knot_holder) { // desktroy knotholder
 164         delete ec->shape_knot_holder;
 165         ec->shape_knot_holder = NULL;
 166     }
 167
 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     }
 173
 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     }
 184 }
 185
 186 static void sp_arc_context_setup(SPEventContext *ec)
 187 {
 188     SPArcContext *ac = SP_ARC_CONTEXT(ec);
 189     Inkscape::Selection *selection = sp_desktop_selection(ec->desktop);
 190
 191     if (((SPEventContextClass *) parent_class)->setup) {
 192         ((SPEventContextClass *) parent_class)->setup(ec);
 193     }
 194
 195     SPItem *item = selection->singleItem();
 196
 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     }
 206
 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         );
 211
 212     if (prefs_get_int_attribute("tools.shapes", "selcue", 0) != 0) {
 213         ec->enableSelectionCue();
 214     }
 215
 216     if (prefs_get_int_attribute("tools.shapes", "gradientdrag", 0) != 0) {
 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
 255     event_context->tolerance = prefs_get_int_attribute_limited("options.dragtolerance", "value", 0, 0, 100);
 256
 257     gint ret = FALSE;
 258
 259     switch (event->type) {
 260         case GDK_BUTTON_PRESS:
 261             if (event->button.button == 1 && !event_context->space_panning) {
 262
 263                 dragging = true;
 264                 ac->center = Inkscape::setup_for_drag_start(desktop, event_context, event);
 265
 266                 /* Snap center */
 267                 SnapManager &m = desktop->namedview->snap_manager;
 268                 m.setup(desktop);
 269                 Geom::Point pt2g = to_2geom(ac->center);
 270                 m.freeSnapReturnByRef(Inkscape::Snapper::SNAPPOINT_NODE, pt2g);
 271                 ac->center = from_2geom(pt2g);
 272
 273                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
 274                                     GDK_KEY_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
 275                                     GDK_POINTER_MOTION_MASK | GDK_POINTER_MOTION_HINT_MASK | GDK_BUTTON_PRESS_MASK,
 276                                     NULL, event->button.time);
 277                 ret = TRUE;
 278             }
 279             break;
 280         case GDK_MOTION_NOTIFY:
 281             if (dragging && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {
 282
 283                 if ( event_context->within_tolerance
 284                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
 285                      && ( abs( (gint) event->motion.y - event_context->yp ) < event_context->tolerance ) ) {
 286                     break; // do not drag if we're within tolerance from origin
 287                 }
 288                 // Once the user has moved farther than tolerance from the original location
 289                 // (indicating they intend to draw, not click), then always process the
 290                 // motion notify coordinates as given (no snapping back to origin)
 291                 event_context->within_tolerance = false;
 292
 293                 Geom::Point const motion_w(event->motion.x, event->motion.y);
 294                 Geom::Point motion_dt(desktop->w2d(motion_w));
 295
 296                 sp_arc_drag(ac, motion_dt, event->motion.state);
 297
 298                 gobble_motion_events(GDK_BUTTON1_MASK);
 299
 300                 ret = TRUE;
 301             }
 302             break;
 303         case GDK_BUTTON_RELEASE:
 304             event_context->xp = event_context->yp = 0;
 305             if (event->button.button == 1 && !event_context->space_panning) {
 306                 dragging = false;
 307                 if (!event_context->within_tolerance) {
 308                     // we've been dragging, finish the arc
 309                     sp_arc_finish(ac);
 310                 } else if (event_context->item_to_select) {
 311                     // no dragging, select clicked item if any
 312                     if (event->button.state & GDK_SHIFT_MASK) {
 313                         selection->toggle(event_context->item_to_select);
 314                     } else {
 315                         selection->set(event_context->item_to_select);
 316                     }
 317                 } else {
 318                     // click in an empty space
 319                     selection->clear();
 320                 }
 321                 event_context->xp = 0;
 322                 event_context->yp = 0;
 323                 event_context->item_to_select = NULL;
 324                 ret = TRUE;
 325             }
 326             sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
 327             break;
 328         case GDK_KEY_PRESS:
 329             switch (get_group0_keyval (&event->key)) {
 330                 case GDK_Alt_L:
 331                 case GDK_Alt_R:
 332                 case GDK_Control_L:
 333                 case GDK_Control_R:
 334                 case GDK_Shift_L:
 335                 case GDK_Shift_R:
 336                 case GDK_Meta_L:  // Meta is when you press Shift+Alt (at least on my machine)
 337                 case GDK_Meta_R:
 338                     if (!dragging) {
 339                         sp_event_show_modifier_tip(event_context->defaultMessageContext(), event,
 340                                                    _("<b>Ctrl</b>: make circle or integer-ratio ellipse, snap arc/segment angle"),
 341                                                    _("<b>Shift</b>: draw around the starting point"),
 342                                                    NULL);
 343                     }
 344                     break;
 345                 case GDK_Up:
 346                 case GDK_Down:
 347                 case GDK_KP_Up:
 348                 case GDK_KP_Down:
 349                     // prevent the zoom field from activation
 350                     if (!MOD__CTRL_ONLY)
 351                         ret = TRUE;
 352                     break;
 353                 case GDK_x:
 354                 case GDK_X:
 355                     if (MOD__ALT_ONLY) {
 356                         desktop->setToolboxFocusTo ("altx-arc");
 357                         ret = TRUE;
 358                     }
 359                     break;
 360                 case GDK_Escape:
 361                     sp_desktop_selection(desktop)->clear();
 362                     //TODO: make dragging escapable by Esc
 363                     break;
 364
 365                 case GDK_space:
 366                     if (dragging) {
 367                         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate),
 368                                               event->button.time);
 369                         dragging = false;
 370                         if (!event_context->within_tolerance) {
 371                             // we've been dragging, finish the rect
 372                             sp_arc_finish(ac);
 373                         }
 374                         // do not return true, so that space would work switching to selector
 375                     }
 376                     break;
 377
 378                 default:
 379                     break;
 380             }
 381             break;
 382         case GDK_KEY_RELEASE:
 383             switch (event->key.keyval) {
 384                 case GDK_Alt_L:
 385                 case GDK_Alt_R:
 386                 case GDK_Control_L:
 387                 case GDK_Control_R:
 388                 case GDK_Shift_L:
 389                 case GDK_Shift_R:
 390                 case GDK_Meta_L:  // Meta is when you press Shift+Alt
 391                 case GDK_Meta_R:
 392                     event_context->defaultMessageContext()->clear();
 393                     break;
 394                 default:
 395                     break;
 396             }
 397             break;
 398         default:
 399             break;
 400     }
 401
 402     if (!ret) {
 403         if (((SPEventContextClass *) parent_class)->root_handler) {
 404             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
 405         }
 406     }
 407
 408     return ret;
 409 }
 410
 411 static void sp_arc_drag(SPArcContext *ac, Geom::Point pt, guint state)
 412 {
 413     SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 414
 415     if (!ac->item) {
 416
 417         if (Inkscape::have_viable_layer(desktop, ac->_message_context) == false) {
 418             return;
 419         }
 420
 421         /* Create object */
 422         Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
 423         Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
 424         repr->setAttribute("sodipodi:type", "arc");
 425
 426         /* Set style */
 427         sp_desktop_apply_style_tool(desktop, repr, "tools.shapes.arc", false);
 428
 429         ac->item = SP_ITEM(desktop->currentLayer()->appendChildRepr(repr));
 430         Inkscape::GC::release(repr);
 431         ac->item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
 432         ac->item->updateRepr();
 433
 434         sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 5);
 435     }
 436
 437     bool ctrl_save = false;
 438     if ((state & GDK_MOD1_MASK) && (state & GDK_CONTROL_MASK) && !(state & GDK_SHIFT_MASK)) {
 439         // if Alt is pressed without Shift in addition to Control, temporarily drop the CONTROL mask
 440         // so that the ellipse is not constrained to integer ratios
 441         ctrl_save = true;
 442         state = state ^ GDK_CONTROL_MASK;
 443     }
 444     Geom::Rect r = Inkscape::snap_rectangular_box(desktop, ac->item, pt, ac->center, state);
 445     if (ctrl_save) {
 446         state = state ^ GDK_CONTROL_MASK;
 447     }
 448
 449     Geom::Point dir = r.dimensions() / 2;
 450     if (state & GDK_MOD1_MASK) {
 451         /* With Alt let the ellipse pass through the mouse pointer */
 452         Geom::Point c = r.midpoint();
 453         if (!ctrl_save) {
 454             if (fabs(dir[Geom::X]) > 1E-6 && fabs(dir[Geom::Y]) > 1E-6) {
 455                 Geom::Matrix const i2d (sp_item_i2d_affine (ac->item));
 456                 Geom::Point new_dir = pt * i2d - c;
 457                 new_dir[Geom::X] *= dir[Geom::Y] / dir[Geom::X];
 458                 double lambda = new_dir.length() / dir[Geom::Y];
 459                 r = Geom::Rect (c - lambda*dir, c + lambda*dir);
 460             }
 461         } else {
 462             /* with Alt+Ctrl (without Shift) we generate a perfect circle
 463                with diameter click point <--> mouse pointer */
 464                 double l = dir.length();
 465                 Geom::Point d (l, l);
 466                 r = Geom::Rect (c - d, c + d);
 467         }
 468     }
 469
 470     sp_arc_position_set(SP_ARC(ac->item),
 471                         r.midpoint()[Geom::X], r.midpoint()[Geom::Y],
 472                         r.dimensions()[Geom::X] / 2, r.dimensions()[Geom::Y] / 2);
 473
 474     double rdimx = r.dimensions()[Geom::X];
 475     double rdimy = r.dimensions()[Geom::Y];
 476     GString *xs = SP_PX_TO_METRIC_STRING(rdimx, desktop->namedview->getDefaultMetric());
 477     GString *ys = SP_PX_TO_METRIC_STRING(rdimy, desktop->namedview->getDefaultMetric());
 478     if (state & GDK_CONTROL_MASK) {
 479         int ratio_x, ratio_y;
 480         if (fabs (rdimx) > fabs (rdimy)) {
 481             ratio_x = (int) rint (rdimx / rdimy);
 482             ratio_y = 1;
 483         } else {
 484             ratio_x = 1;
 485             ratio_y = (int) rint (rdimy / rdimx);
 486         }
 487         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);
 488     } else {
 489         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);
 490     }
 491     g_string_free(xs, FALSE);
 492     g_string_free(ys, FALSE);
 493 }
 494
 495 static void sp_arc_finish(SPArcContext *ac)
 496 {
 497     ac->_message_context->clear();
 498
 499     if (ac->item != NULL) {
 500         SPDesktop *desktop = SP_EVENT_CONTEXT(ac)->desktop;
 501
 502         SP_OBJECT(ac->item)->updateRepr();
 503
 504         sp_canvas_end_forced_full_redraws(desktop->canvas);
 505
 506         sp_desktop_selection(desktop)->set(ac->item);
 507         sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ARC,
 508                          _("Create ellipse"));
 509
 510         ac->item = NULL;
 511     }
 512 }
 513
 514
 515 /*
 516   Local Variables:
 517   mode:c++
 518   c-file-style:"stroustrup"
 519   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 520   indent-tabs-mode:nil
 521   fill-column:99
 522   End:
 523 */
 524 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :