src/pen-context.cpp

   1 /** \file
   2  * Pen event context implementation.
   3  */
   4
   5 /*
   6  * Authors:
   7  *   Lauris Kaplinski <lauris@kaplinski.com>
   8  *   bulia byak <buliabyak@users.sf.net>
   9  *
  10  * Copyright (C) 2000 Lauris Kaplinski
  11  * Copyright (C) 2000-2001 Ximian, Inc.
  12  * Copyright (C) 2002 Lauris Kaplinski
  13  * Copyright (C) 2004 Monash University
  14  *
  15  * Released under GNU GPL, read the file 'COPYING' for more information
  16  */
  17
  18 #include <gdk/gdkkeysyms.h>
  19 #include <cstring>
  20 #include <string>
  21
  22 #include "pen-context.h"
  23 #include "sp-namedview.h"
  24 #include "sp-metrics.h"
  25 #include "desktop.h"
  26 #include "desktop-handles.h"
  27 #include "selection.h"
  28 #include "selection-chemistry.h"
  29 #include "draw-anchor.h"
  30 #include "message-stack.h"
  31 #include "message-context.h"
  32 #include "preferences.h"
  33 #include "sp-path.h"
  34 #include "display/sp-canvas.h"
  35 #include "display/curve.h"
  36 #include "pixmaps/cursor-pen.xpm"
  37 #include "display/canvas-bpath.h"
  38 #include "display/sp-ctrlline.h"
  39 #include "display/sodipodi-ctrl.h"
  40 #include <glibmm/i18n.h>
  41 #include "libnr/nr-point-ops.h"
  42 #include "helper/units.h"
  43 #include "macros.h"
  44 #include "context-fns.h"
  45 #include "tools-switch.h"
  46
  47 static void sp_pen_context_class_init(SPPenContextClass *klass);
  48 static void sp_pen_context_init(SPPenContext *pc);
  49 static void sp_pen_context_dispose(GObject *object);
  50
  51 static void sp_pen_context_setup(SPEventContext *ec);
  52 static void sp_pen_context_finish(SPEventContext *ec);
  53 static void sp_pen_context_set(SPEventContext *ec, Inkscape::Preferences::Entry *val);
  54 static gint sp_pen_context_root_handler(SPEventContext *ec, GdkEvent *event);
  55 static gint sp_pen_context_item_handler(SPEventContext *event_context, SPItem *item, GdkEvent *event);
  56
  57 static void spdc_pen_set_initial_point(SPPenContext *pc, Geom::Point const p);
  58 static void spdc_pen_set_subsequent_point(SPPenContext *const pc, Geom::Point const p, bool statusbar, guint status = 0);
  59 static void spdc_pen_set_ctrl(SPPenContext *pc, Geom::Point const p, guint state);
  60 static void spdc_pen_finish_segment(SPPenContext *pc, Geom::Point p, guint state);
  61
  62 static void spdc_pen_finish(SPPenContext *pc, gboolean closed);
  63
  64 static gint pen_handle_button_press(SPPenContext *const pc, GdkEventButton const &bevent);
  65 static gint pen_handle_motion_notify(SPPenContext *const pc, GdkEventMotion const &mevent);
  66 static gint pen_handle_button_release(SPPenContext *const pc, GdkEventButton const &revent);
  67 static gint pen_handle_2button_press(SPPenContext *const pc, GdkEventButton const &bevent);
  68 static gint pen_handle_key_press(SPPenContext *const pc, GdkEvent *event);
  69 static void spdc_reset_colors(SPPenContext *pc);
  70
  71 static void pen_disable_events(SPPenContext *const pc);
  72 static void pen_enable_events(SPPenContext *const pc);
  73
  74 static Geom::Point pen_drag_origin_w(0, 0);
  75 static bool pen_within_tolerance = false;
  76
  77 static SPDrawContextClass *pen_parent_class;
  78
  79 static int pen_next_paraxial_direction(const SPPenContext *const pc, Geom::Point const &pt, Geom::Point const &origin, guint state);
  80 static void pen_set_to_nearest_horiz_vert(const SPPenContext *const pc, Geom::Point &pt, guint const state, bool snap);
  81
  82 static int pen_last_paraxial_dir = 0; // last used direction in horizontal/vertical mode; 0 = horizontal, 1 = vertical
  83
  84 /**
  85  * Register SPPenContext with Gdk and return its type.
  86  */
  87 GType
  88 sp_pen_context_get_type(void)
  89 {
  90     static GType type = 0;
  91     if (!type) {
  92         GTypeInfo info = {
  93             sizeof(SPPenContextClass),
  94             NULL, NULL,
  95             (GClassInitFunc) sp_pen_context_class_init,
  96             NULL, NULL,
  97             sizeof(SPPenContext),
  98             4,
  99             (GInstanceInitFunc) sp_pen_context_init,
 100             NULL,   /* value_table */
 101         };
 102         type = g_type_register_static(SP_TYPE_DRAW_CONTEXT, "SPPenContext", &info, (GTypeFlags)0);
 103     }
 104     return type;
 105 }
 106
 107 /**
 108  * Initialize the SPPenContext vtable.
 109  */
 110 static void
 111 sp_pen_context_class_init(SPPenContextClass *klass)
 112 {
 113     GObjectClass *object_class;
 114     SPEventContextClass *event_context_class;
 115
 116     object_class = (GObjectClass *) klass;
 117     event_context_class = (SPEventContextClass *) klass;
 118
 119     pen_parent_class = (SPDrawContextClass*)g_type_class_peek_parent(klass);
 120
 121     object_class->dispose = sp_pen_context_dispose;
 122
 123     event_context_class->setup = sp_pen_context_setup;
 124     event_context_class->finish = sp_pen_context_finish;
 125     event_context_class->set = sp_pen_context_set;
 126     event_context_class->root_handler = sp_pen_context_root_handler;
 127     event_context_class->item_handler = sp_pen_context_item_handler;
 128 }
 129
 130 /**
 131  * Callback to initialize SPPenContext object.
 132  */
 133 static void
 134 sp_pen_context_init(SPPenContext *pc)
 135 {
 136
 137     SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
 138
 139     event_context->cursor_shape = cursor_pen_xpm;
 140     event_context->hot_x = 4;
 141     event_context->hot_y = 4;
 142
 143     pc->npoints = 0;
 144     pc->mode = SP_PEN_CONTEXT_MODE_CLICK;
 145     pc->state = SP_PEN_CONTEXT_POINT;
 146
 147     pc->c0 = NULL;
 148     pc->c1 = NULL;
 149     pc->cl0 = NULL;
 150     pc->cl1 = NULL;
 151
 152     pc->events_disabled = 0;
 153
 154     pc->num_clicks = 0;
 155     pc->waiting_LPE = NULL;
 156     pc->waiting_item = NULL;
 157 }
 158
 159 /**
 160  * Callback to destroy the SPPenContext object's members and itself.
 161  */
 162 static void
 163 sp_pen_context_dispose(GObject *object)
 164 {
 165     SPPenContext *pc;
 166
 167     pc = SP_PEN_CONTEXT(object);
 168
 169     if (pc->c0) {
 170         gtk_object_destroy(GTK_OBJECT(pc->c0));
 171         pc->c0 = NULL;
 172     }
 173     if (pc->c1) {
 174         gtk_object_destroy(GTK_OBJECT(pc->c1));
 175         pc->c1 = NULL;
 176     }
 177     if (pc->cl0) {
 178         gtk_object_destroy(GTK_OBJECT(pc->cl0));
 179         pc->cl0 = NULL;
 180     }
 181     if (pc->cl1) {
 182         gtk_object_destroy(GTK_OBJECT(pc->cl1));
 183         pc->cl1 = NULL;
 184     }
 185
 186     G_OBJECT_CLASS(pen_parent_class)->dispose(object);
 187
 188     if (pc->expecting_clicks_for_LPE > 0) {
 189         // we received too few clicks to sanely set the parameter path so we remove the LPE from the item
 190         sp_lpe_item_remove_current_path_effect(pc->waiting_item, false);
 191     }
 192 }
 193
 194 void
 195 sp_pen_context_set_polyline_mode(SPPenContext *const pc) {
 196     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 197     guint mode = prefs->getInt("/tools/freehand/pen/freehand-mode", 0);
 198     pc->polylines_only = (mode == 2 || mode == 3);
 199     pc->polylines_paraxial = (mode == 3);
 200 }
 201
 202 /**
 203  * Callback to initialize SPPenContext object.
 204  */
 205 static void
 206 sp_pen_context_setup(SPEventContext *ec)
 207 {
 208     SPPenContext *pc;
 209
 210     pc = SP_PEN_CONTEXT(ec);
 211
 212     if (((SPEventContextClass *) pen_parent_class)->setup) {
 213         ((SPEventContextClass *) pen_parent_class)->setup(ec);
 214     }
 215
 216     /* Pen indicators */
 217     pc->c0 = sp_canvas_item_new(sp_desktop_controls(SP_EVENT_CONTEXT_DESKTOP(ec)), SP_TYPE_CTRL, "shape", SP_CTRL_SHAPE_CIRCLE,
 218                                 "size", 4.0, "filled", 0, "fill_color", 0xff00007f, "stroked", 1, "stroke_color", 0x0000ff7f, NULL);
 219     pc->c1 = sp_canvas_item_new(sp_desktop_controls(SP_EVENT_CONTEXT_DESKTOP(ec)), SP_TYPE_CTRL, "shape", SP_CTRL_SHAPE_CIRCLE,
 220                                 "size", 4.0, "filled", 0, "fill_color", 0xff00007f, "stroked", 1, "stroke_color", 0x0000ff7f, NULL);
 221     pc->cl0 = sp_canvas_item_new(sp_desktop_controls(SP_EVENT_CONTEXT_DESKTOP(ec)), SP_TYPE_CTRLLINE, NULL);
 222     sp_ctrlline_set_rgba32(SP_CTRLLINE(pc->cl0), 0x0000007f);
 223     pc->cl1 = sp_canvas_item_new(sp_desktop_controls(SP_EVENT_CONTEXT_DESKTOP(ec)), SP_TYPE_CTRLLINE, NULL);
 224     sp_ctrlline_set_rgba32(SP_CTRLLINE(pc->cl1), 0x0000007f);
 225
 226     sp_canvas_item_hide(pc->c0);
 227     sp_canvas_item_hide(pc->c1);
 228     sp_canvas_item_hide(pc->cl0);
 229     sp_canvas_item_hide(pc->cl1);
 230
 231     sp_event_context_read(ec, "mode");
 232
 233     pc->anchor_statusbar = false;
 234
 235     sp_pen_context_set_polyline_mode(pc);
 236
 237     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 238     if (prefs->getBool("/tools/freehand/pen/selcue")) {
 239         ec->enableSelectionCue();
 240     }
 241 }
 242
 243 static void
 244 pen_cancel (SPPenContext *const pc)
 245 {
 246     pc->num_clicks = 0;
 247     pc->state = SP_PEN_CONTEXT_STOP;
 248     spdc_reset_colors(pc);
 249     sp_canvas_item_hide(pc->c0);
 250     sp_canvas_item_hide(pc->c1);
 251     sp_canvas_item_hide(pc->cl0);
 252     sp_canvas_item_hide(pc->cl1);
 253     pc->_message_context->clear();
 254     pc->_message_context->flash(Inkscape::NORMAL_MESSAGE, _("Drawing cancelled"));
 255
 256     sp_canvas_end_forced_full_redraws(pc->desktop->canvas);
 257 }
 258
 259 /**
 260  * Finalization callback.
 261  */
 262 static void
 263 sp_pen_context_finish(SPEventContext *ec)
 264 {
 265     SPPenContext *pc = SP_PEN_CONTEXT(ec);
 266
 267     sp_event_context_discard_delayed_snap_event(ec);
 268
 269     if (pc->npoints != 0) {
 270         pen_cancel (pc);
 271     }
 272
 273     if (((SPEventContextClass *) pen_parent_class)->finish) {
 274         ((SPEventContextClass *) pen_parent_class)->finish(ec);
 275     }
 276 }
 277
 278 /**
 279  * Callback that sets key to value in pen context.
 280  */
 281 static void
 282 sp_pen_context_set(SPEventContext *ec, Inkscape::Preferences::Entry *val)
 283 {
 284     SPPenContext *pc = SP_PEN_CONTEXT(ec);
 285     Glib::ustring name = val->getEntryName();
 286
 287     if (name == "mode") {
 288         if ( val->getString() == "drag" ) {
 289             pc->mode = SP_PEN_CONTEXT_MODE_DRAG;
 290         } else {
 291             pc->mode = SP_PEN_CONTEXT_MODE_CLICK;
 292         }
 293     }
 294 }
 295
 296 /**
 297  * Snaps new node relative to the previous node.
 298  */
 299 static void
 300 spdc_endpoint_snap(SPPenContext const *const pc, Geom::Point &p, guint const state)
 301 {
 302     if ((state & GDK_CONTROL_MASK) && !pc->polylines_paraxial) { //CTRL enables angular snapping
 303         if (pc->npoints > 0) {
 304             spdc_endpoint_snap_rotation(pc, p, pc->p[0], state);
 305         }
 306     } else {
 307         // We cannot use shift here to disable snapping because the shift-key is already used
 308         // to toggle the paraxial direction; if the user wants to disable snapping (s)he will
 309         // have to use the %-key, the menu, or the snap toolbar
 310         if ((pc->npoints > 0) && pc->polylines_paraxial) {
 311             // snap constrained
 312             pen_set_to_nearest_horiz_vert(pc, p, state, true);
 313         } else {
 314             // snap freely
 315             spdc_endpoint_snap_free(pc, p, state);
 316         }
 317     }
 318 }
 319
 320 /**
 321  * Snaps new node's handle relative to the new node.
 322  */
 323 static void
 324 spdc_endpoint_snap_handle(SPPenContext const *const pc, Geom::Point &p, guint const state)
 325 {
 326     g_return_if_fail(( pc->npoints == 2 ||
 327                        pc->npoints == 5   ));
 328
 329     if ((state & GDK_CONTROL_MASK)) { //CTRL enables angular snapping
 330         spdc_endpoint_snap_rotation(pc, p, pc->p[pc->npoints - 2], state);
 331     } else {
 332         if (!(state & GDK_SHIFT_MASK)) { //SHIFT disables all snapping, except the angular snapping above
 333             spdc_endpoint_snap_free(pc, p, state);
 334         }
 335     }
 336 }
 337
 338 static gint
 339 sp_pen_context_item_handler(SPEventContext *ec, SPItem *item, GdkEvent *event)
 340 {
 341     SPPenContext *const pc = SP_PEN_CONTEXT(ec);
 342
 343     gint ret = FALSE;
 344
 345     switch (event->type) {
 346         case GDK_BUTTON_PRESS:
 347             ret = pen_handle_button_press(pc, event->button);
 348             break;
 349         case GDK_BUTTON_RELEASE:
 350             ret = pen_handle_button_release(pc, event->button);
 351             break;
 352         default:
 353             break;
 354     }
 355
 356     if (!ret) {
 357         if (((SPEventContextClass *) pen_parent_class)->item_handler)
 358             ret = ((SPEventContextClass *) pen_parent_class)->item_handler(ec, item, event);
 359     }
 360
 361     return ret;
 362 }
 363
 364 /**
 365  * Callback to handle all pen events.
 366  */
 367 static gint
 368 sp_pen_context_root_handler(SPEventContext *ec, GdkEvent *event)
 369 {
 370     SPPenContext *const pc = SP_PEN_CONTEXT(ec);
 371
 372     gint ret = FALSE;
 373
 374     switch (event->type) {
 375         case GDK_BUTTON_PRESS:
 376             ret = pen_handle_button_press(pc, event->button);
 377             break;
 378
 379         case GDK_MOTION_NOTIFY:
 380             ret = pen_handle_motion_notify(pc, event->motion);
 381             break;
 382
 383         case GDK_BUTTON_RELEASE:
 384             ret = pen_handle_button_release(pc, event->button);
 385             break;
 386
 387         case GDK_2BUTTON_PRESS:
 388             ret = pen_handle_2button_press(pc, event->button);
 389             break;
 390
 391         case GDK_KEY_PRESS:
 392             ret = pen_handle_key_press(pc, event);
 393             break;
 394
 395         default:
 396             break;
 397     }
 398
 399     if (!ret) {
 400         gint (*const parent_root_handler)(SPEventContext *, GdkEvent *)
 401             = ((SPEventContextClass *) pen_parent_class)->root_handler;
 402         if (parent_root_handler) {
 403             ret = parent_root_handler(ec, event);
 404         }
 405     }
 406
 407     return ret;
 408 }
 409
 410 /**
 411  * Handle mouse button press event.
 412  */
 413 static gint pen_handle_button_press(SPPenContext *const pc, GdkEventButton const &bevent)
 414 {
 415     if (pc->events_disabled) {
 416         // skip event processing if events are disabled
 417         return FALSE;
 418     }
 419
 420     SPDrawContext * const dc = SP_DRAW_CONTEXT(pc);
 421     SPDesktop * const desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
 422     Geom::Point const event_w(bevent.x, bevent.y);
 423     Geom::Point event_dt(desktop->w2d(event_w));
 424     SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
 425
 426     gint ret = FALSE;
 427     if (bevent.button == 1 && !event_context->space_panning
 428         // make sure this is not the last click for a waiting LPE (otherwise we want to finish the path)
 429         && pc->expecting_clicks_for_LPE != 1) {
 430
 431         if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
 432             return TRUE;
 433         }
 434
 435         if (!pc->grab ) {
 436             /* Grab mouse, so release will not pass unnoticed */
 437             pc->grab = SP_CANVAS_ITEM(desktop->acetate);
 438             sp_canvas_item_grab(pc->grab, ( GDK_KEY_PRESS_MASK | GDK_BUTTON_PRESS_MASK   |
 439                                             GDK_BUTTON_RELEASE_MASK |
 440                                             GDK_POINTER_MOTION_MASK  ),
 441                                 NULL, bevent.time);
 442         }
 443
 444         pen_drag_origin_w = event_w;
 445         pen_within_tolerance = true;
 446
 447         /* Test whether we hit any anchor. */
 448         SPDrawAnchor * const anchor = spdc_test_inside(pc, event_w);
 449
 450         switch (pc->mode) {
 451             case SP_PEN_CONTEXT_MODE_CLICK:
 452                 /* In click mode we add point on release */
 453                 switch (pc->state) {
 454                     case SP_PEN_CONTEXT_POINT:
 455                     case SP_PEN_CONTEXT_CONTROL:
 456                     case SP_PEN_CONTEXT_CLOSE:
 457                         break;
 458                     case SP_PEN_CONTEXT_STOP:
 459                         /* This is allowed, if we just canceled curve */
 460                         pc->state = SP_PEN_CONTEXT_POINT;
 461                         break;
 462                     default:
 463                         break;
 464                 }
 465                 break;
 466             case SP_PEN_CONTEXT_MODE_DRAG:
 467                 switch (pc->state) {
 468                     case SP_PEN_CONTEXT_STOP:
 469                         /* This is allowed, if we just canceled curve */
 470                     case SP_PEN_CONTEXT_POINT:
 471                         if (pc->npoints == 0) {
 472
 473                             Geom::Point p;
 474                             if ((bevent.state & GDK_CONTROL_MASK) && (pc->polylines_only || pc->polylines_paraxial)) {
 475                                 p = event_dt;
 476                                 if (!(bevent.state & GDK_SHIFT_MASK)) {
 477                                     SnapManager &m = desktop->namedview->snap_manager;
 478                                     m.setup(desktop);
 479                                     m.freeSnapReturnByRef(p, Inkscape::SNAPSOURCE_NODE_HANDLE);
 480                                     m.unSetup();
 481                                 }
 482                               spdc_create_single_dot(event_context, p, "/tools/freehand/pen", bevent.state);
 483                               ret = TRUE;
 484                               break;
 485                             }
 486
 487                             // TODO: Perhaps it would be nicer to rearrange the following case
 488                             // distinction so that the case of a waiting LPE is treated separately
 489
 490                             /* Set start anchor */
 491                             pc->sa = anchor;
 492                             if (anchor && !sp_pen_context_has_waiting_LPE(pc)) {
 493                                 /* Adjust point to anchor if needed; if we have a waiting LPE, we need
 494                                    a fresh path to be created so don't continue an existing one */
 495                                 p = anchor->dp;
 496                                 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Continuing selected path"));
 497                             } else {
 498                                 // This is the first click of a new curve; deselect item so that
 499                                 // this curve is not combined with it (unless it is drawn from its
 500                                 // anchor, which is handled by the sibling branch above)
 501                                 Inkscape::Selection * const selection = sp_desktop_selection(desktop);
 502                                 if (!(bevent.state & GDK_SHIFT_MASK) || sp_pen_context_has_waiting_LPE(pc)) {
 503                                     /* if we have a waiting LPE, we need a fresh path to be created
 504                                        so don't append to an existing one */
 505                                     selection->clear();
 506                                     desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Creating new path"));
 507                                 } else if (selection->singleItem() && SP_IS_PATH(selection->singleItem())) {
 508                                     desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Appending to selected path"));
 509                                 }
 510
 511                                 /* Create green anchor */
 512                                 p = event_dt;
 513                                 spdc_endpoint_snap(pc, p, bevent.state);
 514                                 pc->green_anchor = sp_draw_anchor_new(pc, pc->green_curve, TRUE, p);
 515                             }
 516                             spdc_pen_set_initial_point(pc, p);
 517                         } else {
 518
 519                             /* Set end anchor */
 520                             pc->ea = anchor;
 521                             Geom::Point p;
 522                             if (anchor) {
 523                                 p = anchor->dp;
 524                                 // we hit an anchor, will finish the curve (either with or without closing)
 525                                 // in release handler
 526                                 pc->state = SP_PEN_CONTEXT_CLOSE;
 527
 528                                 if (pc->green_anchor && pc->green_anchor->active) {
 529                                     // we clicked on the current curve start, so close it even if
 530                                     // we drag a handle away from it
 531                                     dc->green_closed = TRUE;
 532                                 }
 533                                 ret = TRUE;
 534                                 break;
 535
 536                             } else {
 537                                 p = event_dt;
 538                                 spdc_endpoint_snap(pc, p, bevent.state); /* Snap node only if not hitting anchor. */
 539                                 spdc_pen_set_subsequent_point(pc, p, true);
 540                             }
 541                         }
 542
 543                         pc->state = pc->polylines_only ? SP_PEN_CONTEXT_POINT : SP_PEN_CONTEXT_CONTROL;
 544                         ret = TRUE;
 545                         break;
 546                     case SP_PEN_CONTEXT_CONTROL:
 547                         g_warning("Button down in CONTROL state");
 548                         break;
 549                     case SP_PEN_CONTEXT_CLOSE:
 550                         g_warning("Button down in CLOSE state");
 551                         break;
 552                     default:
 553                         break;
 554                 }
 555                 break;
 556             default:
 557                 break;
 558         }
 559     } else if (pc->expecting_clicks_for_LPE == 1 && pc->npoints != 0) {
 560         // when the last click for a waiting LPE occurs we want to finish the path
 561         spdc_pen_finish_segment(pc, event_dt, bevent.state);
 562         if (pc->green_closed) {
 563             // finishing at the start anchor, close curve
 564             spdc_pen_finish(pc, TRUE);
 565         } else {
 566             // finishing at some other anchor, finish curve but not close
 567             spdc_pen_finish(pc, FALSE);
 568         }
 569
 570         ret = TRUE;
 571     } else if (bevent.button == 3 && pc->npoints != 0) {
 572         // right click - finish path
 573         spdc_pen_finish(pc, FALSE);
 574         ret = TRUE;
 575     }
 576
 577     if (pc->expecting_clicks_for_LPE > 0) {
 578         --pc->expecting_clicks_for_LPE;
 579     }
 580
 581     return ret;
 582 }
 583
 584 /**
 585  * Handle motion_notify event.
 586  */
 587 static gint
 588 pen_handle_motion_notify(SPPenContext *const pc, GdkEventMotion const &mevent)
 589 {
 590     gint ret = FALSE;
 591
 592     SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
 593     SPDesktop * const dt = SP_EVENT_CONTEXT_DESKTOP(event_context);
 594
 595     if (event_context->space_panning || mevent.state & GDK_BUTTON2_MASK || mevent.state & GDK_BUTTON3_MASK) {
 596         // allow scrolling
 597         return FALSE;
 598     }
 599
 600     if (pc->events_disabled) {
 601         // skip motion events if pen events are disabled
 602         return FALSE;
 603     }
 604
 605     Geom::Point const event_w(mevent.x,
 606                             mevent.y);
 607     if (pen_within_tolerance) {
 608         Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 609         gint const tolerance = prefs->getIntLimited("/options/dragtolerance/value", 0, 0, 100);
 610         if ( Geom::LInfty( event_w - pen_drag_origin_w ) < tolerance ) {
 611             return FALSE;   // Do not drag if we're within tolerance from origin.
 612         }
 613     }
 614     // Once the user has moved farther than tolerance from the original location
 615     // (indicating they intend to move the object, not click), then always process the
 616     // motion notify coordinates as given (no snapping back to origin)
 617     pen_within_tolerance = false;
 618
 619     /* Find desktop coordinates */
 620     Geom::Point p = dt->w2d(event_w);
 621
 622     /* Test, whether we hit any anchor */
 623     SPDrawAnchor *anchor = spdc_test_inside(pc, event_w);
 624
 625     switch (pc->mode) {
 626         case SP_PEN_CONTEXT_MODE_CLICK:
 627             switch (pc->state) {
 628                 case SP_PEN_CONTEXT_POINT:
 629                     if ( pc->npoints != 0 ) {
 630                         /* Only set point, if we are already appending */
 631                         spdc_endpoint_snap(pc, p, mevent.state);
 632                         spdc_pen_set_subsequent_point(pc, p, true);
 633                         ret = TRUE;
 634                     } else if (!sp_event_context_knot_mouseover(pc)) {
 635                         SnapManager &m = dt->namedview->snap_manager;
 636                         m.setup(dt);
 637                         m.preSnap(Inkscape::SnapCandidatePoint(p, Inkscape::SNAPSOURCE_NODE_HANDLE));
 638                         m.unSetup();
 639                     }
 640                     break;
 641                 case SP_PEN_CONTEXT_CONTROL:
 642                 case SP_PEN_CONTEXT_CLOSE:
 643                     /* Placing controls is last operation in CLOSE state */
 644                     spdc_endpoint_snap(pc, p, mevent.state);
 645                     spdc_pen_set_ctrl(pc, p, mevent.state);
 646                     ret = TRUE;
 647                     break;
 648                 case SP_PEN_CONTEXT_STOP:
 649                     /* This is perfectly valid */
 650                     break;
 651                 default:
 652                     break;
 653             }
 654             break;
 655         case SP_PEN_CONTEXT_MODE_DRAG:
 656             switch (pc->state) {
 657                 case SP_PEN_CONTEXT_POINT:
 658                     if ( pc->npoints > 0 ) {
 659                         /* Only set point, if we are already appending */
 660
 661                         if (!anchor) {   /* Snap node only if not hitting anchor */
 662                             spdc_endpoint_snap(pc, p, mevent.state);
 663                             spdc_pen_set_subsequent_point(pc, p, true, mevent.state);
 664                         } else {
 665                             spdc_pen_set_subsequent_point(pc, anchor->dp, false, mevent.state);
 666                         }
 667
 668                         if (anchor && !pc->anchor_statusbar) {
 669                             pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Click</b> or <b>click and drag</b> to close and finish the path."));
 670                             pc->anchor_statusbar = true;
 671                         } else if (!anchor && pc->anchor_statusbar) {
 672                             pc->_message_context->clear();
 673                             pc->anchor_statusbar = false;
 674                         }
 675
 676                         ret = TRUE;
 677                     } else {
 678                         if (anchor && !pc->anchor_statusbar) {
 679                             pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Click</b> or <b>click and drag</b> to continue the path from this point."));
 680                             pc->anchor_statusbar = true;
 681                         } else if (!anchor && pc->anchor_statusbar) {
 682                             pc->_message_context->clear();
 683                             pc->anchor_statusbar = false;
 684                         }
 685                         if (!sp_event_context_knot_mouseover(pc)) {
 686                             SnapManager &m = dt->namedview->snap_manager;
 687                             m.setup(dt);
 688                             m.preSnap(Inkscape::SnapCandidatePoint(p, Inkscape::SNAPSOURCE_NODE_HANDLE));
 689                             m.unSetup();
 690                         }
 691                     }
 692                     break;
 693                 case SP_PEN_CONTEXT_CONTROL:
 694                 case SP_PEN_CONTEXT_CLOSE:
 695                     /* Placing controls is last operation in CLOSE state */
 696
 697                     // snap the handle
 698                     spdc_endpoint_snap_handle(pc, p, mevent.state);
 699
 700                     if (!pc->polylines_only) {
 701                         spdc_pen_set_ctrl(pc, p, mevent.state);
 702                     } else {
 703                         spdc_pen_set_ctrl(pc, pc->p[1], mevent.state);
 704                     }
 705                     gobble_motion_events(GDK_BUTTON1_MASK);
 706                     ret = TRUE;
 707                     break;
 708                 case SP_PEN_CONTEXT_STOP:
 709                     /* This is perfectly valid */
 710                     break;
 711                 default:
 712                     if (!sp_event_context_knot_mouseover(pc)) {
 713                         SnapManager &m = dt->namedview->snap_manager;
 714                         m.setup(dt);
 715                         m.preSnap(Inkscape::SnapCandidatePoint(p, Inkscape::SNAPSOURCE_NODE_HANDLE));
 716                         m.unSetup();
 717                     }
 718                     break;
 719             }
 720             break;
 721         default:
 722             break;
 723     }
 724     return ret;
 725 }
 726
 727 /**
 728  * Handle mouse button release event.
 729  */
 730 static gint
 731 pen_handle_button_release(SPPenContext *const pc, GdkEventButton const &revent)
 732 {
 733     if (pc->events_disabled) {
 734         // skip event processing if events are disabled
 735         return FALSE;
 736     }
 737
 738     gint ret = FALSE;
 739     SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
 740     if ( revent.button == 1  && !event_context->space_panning) {
 741
 742         SPDrawContext *dc = SP_DRAW_CONTEXT (pc);
 743
 744         Geom::Point const event_w(revent.x,
 745                                 revent.y);
 746         /* Find desktop coordinates */
 747         Geom::Point p = pc->desktop->w2d(event_w);
 748
 749         /* Test whether we hit any anchor. */
 750         SPDrawAnchor *anchor = spdc_test_inside(pc, event_w);
 751
 752         switch (pc->mode) {
 753             case SP_PEN_CONTEXT_MODE_CLICK:
 754                 switch (pc->state) {
 755                     case SP_PEN_CONTEXT_POINT:
 756                         if ( pc->npoints == 0 ) {
 757                             /* Start new thread only with button release */
 758                             if (anchor) {
 759                                 p = anchor->dp;
 760                             }
 761                             pc->sa = anchor;
 762                             spdc_pen_set_initial_point(pc, p);
 763                         } else {
 764                             /* Set end anchor here */
 765                             pc->ea = anchor;
 766                             if (anchor) {
 767                                 p = anchor->dp;
 768                             }
 769                         }
 770                         pc->state = SP_PEN_CONTEXT_CONTROL;
 771                         ret = TRUE;
 772                         break;
 773                     case SP_PEN_CONTEXT_CONTROL:
 774                         /* End current segment */
 775                         spdc_endpoint_snap(pc, p, revent.state);
 776                         spdc_pen_finish_segment(pc, p, revent.state);
 777                         pc->state = SP_PEN_CONTEXT_POINT;
 778                         ret = TRUE;
 779                         break;
 780                     case SP_PEN_CONTEXT_CLOSE:
 781                         /* End current segment */
 782                         if (!anchor) {   /* Snap node only if not hitting anchor */
 783                             spdc_endpoint_snap(pc, p, revent.state);
 784                         }
 785                         spdc_pen_finish_segment(pc, p, revent.state);
 786                         spdc_pen_finish(pc, TRUE);
 787                         pc->state = SP_PEN_CONTEXT_POINT;
 788                         ret = TRUE;
 789                         break;
 790                     case SP_PEN_CONTEXT_STOP:
 791                         /* This is allowed, if we just canceled curve */
 792                         pc->state = SP_PEN_CONTEXT_POINT;
 793                         ret = TRUE;
 794                         break;
 795                     default:
 796                         break;
 797                 }
 798                 break;
 799             case SP_PEN_CONTEXT_MODE_DRAG:
 800                 switch (pc->state) {
 801                     case SP_PEN_CONTEXT_POINT:
 802                     case SP_PEN_CONTEXT_CONTROL:
 803                         spdc_endpoint_snap(pc, p, revent.state);
 804                         spdc_pen_finish_segment(pc, p, revent.state);
 805                         break;
 806                     case SP_PEN_CONTEXT_CLOSE:
 807                         spdc_endpoint_snap(pc, p, revent.state);
 808                         spdc_pen_finish_segment(pc, p, revent.state);
 809                         if (pc->green_closed) {
 810                             // finishing at the start anchor, close curve
 811                             spdc_pen_finish(pc, TRUE);
 812                         } else {
 813                             // finishing at some other anchor, finish curve but not close
 814                             spdc_pen_finish(pc, FALSE);
 815                         }
 816                         break;
 817                     case SP_PEN_CONTEXT_STOP:
 818                         /* This is allowed, if we just cancelled curve */
 819                         break;
 820                     default:
 821                         break;
 822                 }
 823                 pc->state = SP_PEN_CONTEXT_POINT;
 824                 ret = TRUE;
 825                 break;
 826             default:
 827                 break;
 828         }
 829
 830         if (pc->grab) {
 831             /* Release grab now */
 832             sp_canvas_item_ungrab(pc->grab, revent.time);
 833             pc->grab = NULL;
 834         }
 835
 836         ret = TRUE;
 837
 838         dc->green_closed = FALSE;
 839     }
 840
 841     // TODO: can we be sure that the path was created correctly?
 842     // TODO: should we offer an option to collect the clicks in a list?
 843     if (pc->expecting_clicks_for_LPE == 0 && sp_pen_context_has_waiting_LPE(pc)) {
 844         sp_pen_context_set_polyline_mode(pc);
 845
 846         SPEventContext *ec = SP_EVENT_CONTEXT(pc);
 847         Inkscape::Selection *selection = sp_desktop_selection (ec->desktop);
 848
 849         if (pc->waiting_LPE) {
 850             // we have an already created LPE waiting for a path
 851             pc->waiting_LPE->acceptParamPath(SP_PATH(selection->singleItem()));
 852             selection->add(SP_OBJECT(pc->waiting_item));
 853             pc->waiting_LPE = NULL;
 854         } else {
 855             // the case that we need to create a new LPE and apply it to the just-drawn path is
 856             // handled in spdc_check_for_and_apply_waiting_LPE() in draw-context.cpp
 857         }
 858     }
 859
 860     return ret;
 861 }
 862
 863 static gint
 864 pen_handle_2button_press(SPPenContext *const pc, GdkEventButton const &bevent)
 865 {
 866     gint ret = FALSE;
 867     // only end on LMB double click. Otherwise horizontal scrolling causes ending of the path
 868     if (pc->npoints != 0 && bevent.button == 1) {
 869         spdc_pen_finish(pc, FALSE);
 870         ret = TRUE;
 871     }
 872     return ret;
 873 }
 874
 875 void
 876 pen_redraw_all (SPPenContext *const pc)
 877 {
 878     // green
 879     if (pc->green_bpaths) {
 880         // remove old piecewise green canvasitems
 881         while (pc->green_bpaths) {
 882             gtk_object_destroy(GTK_OBJECT(pc->green_bpaths->data));
 883             pc->green_bpaths = g_slist_remove(pc->green_bpaths, pc->green_bpaths->data);
 884         }
 885         // one canvas bpath for all of green_curve
 886         SPCanvasItem *cshape = sp_canvas_bpath_new(sp_desktop_sketch(pc->desktop), pc->green_curve);
 887         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cshape), pc->green_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 888         sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(cshape), 0, SP_WIND_RULE_NONZERO);
 889
 890         pc->green_bpaths = g_slist_prepend(pc->green_bpaths, cshape);
 891     }
 892
 893     if (pc->green_anchor)
 894         SP_CTRL(pc->green_anchor->ctrl)->moveto(pc->green_anchor->dp);
 895
 896     pc->red_curve->reset();
 897     pc->red_curve->moveto(pc->p[0]);
 898     pc->red_curve->curveto(pc->p[1], pc->p[2], pc->p[3]);
 899     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
 900
 901     // handles
 902     if (pc->p[0] != pc->p[1]) {
 903         SP_CTRL(pc->c1)->moveto(pc->p[1]);
 904         sp_ctrlline_set_coords(SP_CTRLLINE(pc->cl1), pc->p[0], pc->p[1]);
 905         sp_canvas_item_show (pc->c1);
 906         sp_canvas_item_show (pc->cl1);
 907     } else {
 908         sp_canvas_item_hide (pc->c1);
 909         sp_canvas_item_hide (pc->cl1);
 910     }
 911
 912     Geom::Curve const * last_seg = pc->green_curve->last_segment();
 913     if (last_seg) {
 914         Geom::CubicBezier const * cubic = dynamic_cast<Geom::CubicBezier const *>( last_seg );
 915         if ( cubic &&
 916              (*cubic)[2] != to_2geom(pc->p[0]) )
 917         {
 918             Geom::Point p2 = (*cubic)[2];
 919             SP_CTRL(pc->c0)->moveto(p2);
 920             sp_ctrlline_set_coords(SP_CTRLLINE(pc->cl0), p2, pc->p[0]);
 921             sp_canvas_item_show (pc->c0);
 922             sp_canvas_item_show (pc->cl0);
 923         } else {
 924             sp_canvas_item_hide (pc->c0);
 925             sp_canvas_item_hide (pc->cl0);
 926         }
 927     }
 928 }
 929
 930 void
 931 pen_lastpoint_move (SPPenContext *const pc, gdouble x, gdouble y)
 932 {
 933     if (pc->npoints != 5)
 934         return;
 935
 936     // green
 937     if (!pc->green_curve->is_empty()) {
 938         pc->green_curve->last_point_additive_move( Geom::Point(x,y) );
 939     } else {
 940         // start anchor too
 941         if (pc->green_anchor) {
 942             pc->green_anchor->dp += Geom::Point(x, y);
 943         }
 944     }
 945
 946     // red
 947     pc->p[0] += Geom::Point(x, y);
 948     pc->p[1] += Geom::Point(x, y);
 949     pen_redraw_all(pc);
 950 }
 951
 952 void
 953 pen_lastpoint_move_screen (SPPenContext *const pc, gdouble x, gdouble y)
 954 {
 955     pen_lastpoint_move (pc, x / pc->desktop->current_zoom(), y / pc->desktop->current_zoom());
 956 }
 957
 958 void
 959 pen_lastpoint_tocurve (SPPenContext *const pc)
 960 {
 961     if (pc->npoints != 5)
 962         return;
 963
 964     Geom::CubicBezier const * cubic = dynamic_cast<Geom::CubicBezier const *>( pc->green_curve->last_segment() );
 965     if ( cubic ) {
 966         pc->p[1] = pc->p[0] + (Geom::Point)( (*cubic)[3] - (*cubic)[2] );
 967     } else {
 968         pc->p[1] = pc->p[0] + (1./3)*(pc->p[3] - pc->p[0]);
 969     }
 970
 971     pen_redraw_all(pc);
 972 }
 973
 974 void
 975 pen_lastpoint_toline (SPPenContext *const pc)
 976 {
 977     if (pc->npoints != 5)
 978         return;
 979
 980     pc->p[1] = pc->p[0];
 981
 982     pen_redraw_all(pc);
 983 }
 984
 985
 986 static gint
 987 pen_handle_key_press(SPPenContext *const pc, GdkEvent *event)
 988 {
 989
 990     gint ret = FALSE;
 991     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 992     gdouble const nudge = prefs->getDoubleLimited("/options/nudgedistance/value", 2, 0, 1000); // in px
 993
 994     switch (get_group0_keyval (&event->key)) {
 995
 996         case GDK_Left: // move last point left
 997         case GDK_KP_Left:
 998         case GDK_KP_4:
 999             if (!MOD__CTRL) { // not ctrl
1000                 if (MOD__ALT) { // alt
1001                     if (MOD__SHIFT) pen_lastpoint_move_screen(pc, -10, 0); // shift
1002                     else pen_lastpoint_move_screen(pc, -1, 0); // no shift
1003                 }
1004                 else { // no alt
1005                     if (MOD__SHIFT) pen_lastpoint_move(pc, -10*nudge, 0); // shift
1006                     else pen_lastpoint_move(pc, -nudge, 0); // no shift
1007                 }
1008                 ret = TRUE;
1009             }
1010             break;
1011         case GDK_Up: // move last point up
1012         case GDK_KP_Up:
1013         case GDK_KP_8:
1014             if (!MOD__CTRL) { // not ctrl
1015                 if (MOD__ALT) { // alt
1016                     if (MOD__SHIFT) pen_lastpoint_move_screen(pc, 0, 10); // shift
1017                     else pen_lastpoint_move_screen(pc, 0, 1); // no shift
1018                 }
1019                 else { // no alt
1020                     if (MOD__SHIFT) pen_lastpoint_move(pc, 0, 10*nudge); // shift
1021                     else pen_lastpoint_move(pc, 0, nudge); // no shift
1022                 }
1023                 ret = TRUE;
1024             }
1025             break;
1026         case GDK_Right: // move last point right
1027         case GDK_KP_Right:
1028         case GDK_KP_6:
1029             if (!MOD__CTRL) { // not ctrl
1030                 if (MOD__ALT) { // alt
1031                     if (MOD__SHIFT) pen_lastpoint_move_screen(pc, 10, 0); // shift
1032                     else pen_lastpoint_move_screen(pc, 1, 0); // no shift
1033                 }
1034                 else { // no alt
1035                     if (MOD__SHIFT) pen_lastpoint_move(pc, 10*nudge, 0); // shift
1036                     else pen_lastpoint_move(pc, nudge, 0); // no shift
1037                 }
1038                 ret = TRUE;
1039             }
1040             break;
1041         case GDK_Down: // move last point down
1042         case GDK_KP_Down:
1043         case GDK_KP_2:
1044             if (!MOD__CTRL) { // not ctrl
1045                 if (MOD__ALT) { // alt
1046                     if (MOD__SHIFT) pen_lastpoint_move_screen(pc, 0, -10); // shift
1047                     else pen_lastpoint_move_screen(pc, 0, -1); // no shift
1048                 }
1049                 else { // no alt
1050                     if (MOD__SHIFT) pen_lastpoint_move(pc, 0, -10*nudge); // shift
1051                     else pen_lastpoint_move(pc, 0, -nudge); // no shift
1052                 }
1053                 ret = TRUE;
1054             }
1055             break;
1056
1057 /* TODO: this is not yet enabled?? looks like some traces of the Geometry tool
1058         case GDK_P:
1059         case GDK_p:
1060             if (MOD__SHIFT_ONLY) {
1061                 sp_pen_context_wait_for_LPE_mouse_clicks(pc, Inkscape::LivePathEffect::PARALLEL, 2);
1062                 ret = TRUE;
1063             }
1064             break;
1065
1066         case GDK_C:
1067         case GDK_c:
1068             if (MOD__SHIFT_ONLY) {
1069                 sp_pen_context_wait_for_LPE_mouse_clicks(pc, Inkscape::LivePathEffect::CIRCLE_3PTS, 3);
1070                 ret = TRUE;
1071             }
1072             break;
1073
1074         case GDK_B:
1075         case GDK_b:
1076             if (MOD__SHIFT_ONLY) {
1077                 sp_pen_context_wait_for_LPE_mouse_clicks(pc, Inkscape::LivePathEffect::PERP_BISECTOR, 2);
1078                 ret = TRUE;
1079             }
1080             break;
1081
1082         case GDK_A:
1083         case GDK_a:
1084             if (MOD__SHIFT_ONLY) {
1085                 sp_pen_context_wait_for_LPE_mouse_clicks(pc, Inkscape::LivePathEffect::ANGLE_BISECTOR, 3);
1086                 ret = TRUE;
1087             }
1088             break;
1089 */
1090
1091         case GDK_U:
1092         case GDK_u:
1093             if (MOD__SHIFT_ONLY) {
1094                 pen_lastpoint_tocurve(pc);
1095                 ret = TRUE;
1096             }
1097             break;
1098         case GDK_L:
1099         case GDK_l:
1100             if (MOD__SHIFT_ONLY) {
1101                 pen_lastpoint_toline(pc);
1102                 ret = TRUE;
1103             }
1104             break;
1105
1106         case GDK_Return:
1107         case GDK_KP_Enter:
1108             if (pc->npoints != 0) {
1109                 spdc_pen_finish(pc, FALSE);
1110                 ret = TRUE;
1111             }
1112             break;
1113         case GDK_Escape:
1114             if (pc->npoints != 0) {
1115                 // if drawing, cancel, otherwise pass it up for deselecting
1116                 pen_cancel (pc);
1117                 ret = TRUE;
1118             }
1119             break;
1120         case GDK_z:
1121         case GDK_Z:
1122             if (MOD__CTRL_ONLY && pc->npoints != 0) {
1123                 // if drawing, cancel, otherwise pass it up for undo
1124                 pen_cancel (pc);
1125                 ret = TRUE;
1126             }
1127             break;
1128         case GDK_g:
1129         case GDK_G:
1130             if (MOD__SHIFT_ONLY) {
1131                 sp_selection_to_guides(SP_EVENT_CONTEXT(pc)->desktop);
1132                 ret = true;
1133             }
1134             break;
1135         case GDK_BackSpace:
1136         case GDK_Delete:
1137         case GDK_KP_Delete:
1138             if ( pc->green_curve->is_empty() || (pc->green_curve->last_segment() == NULL) ) {
1139                 if (!pc->red_curve->is_empty()) {
1140                     pen_cancel (pc);
1141                     ret = TRUE;
1142                 } else {
1143                     // do nothing; this event should be handled upstream
1144                 }
1145             } else {
1146                 /* Reset red curve */
1147                 pc->red_curve->reset();
1148                 /* Destroy topmost green bpath */
1149                 if (pc->green_bpaths) {
1150                     if (pc->green_bpaths->data)
1151                         gtk_object_destroy(GTK_OBJECT(pc->green_bpaths->data));
1152                     pc->green_bpaths = g_slist_remove(pc->green_bpaths, pc->green_bpaths->data);
1153                 }
1154                 /* Get last segment */
1155                 if ( pc->green_curve->is_empty() ) {
1156                     g_warning("pen_handle_key_press, case GDK_KP_Delete: Green curve is empty");
1157                     break;
1158                 }
1159                 // The code below assumes that pc->green_curve has only ONE path !
1160                 Geom::Curve const * crv = pc->green_curve->last_segment();
1161                 pc->p[0] = crv->initialPoint();
1162                 if ( Geom::CubicBezier const * cubic = dynamic_cast<Geom::CubicBezier const *>(crv)) {
1163                     pc->p[1] = (*cubic)[1];
1164                 } else {
1165                     pc->p[1] = pc->p[0];
1166                 }
1167                 Geom::Point const pt(( pc->npoints < 4
1168                                      ? (Geom::Point)(crv->finalPoint())
1169                                      : pc->p[3] ));
1170                 pc->npoints = 2;
1171                 pc->green_curve->backspace();
1172                 sp_canvas_item_hide(pc->c0);
1173                 sp_canvas_item_hide(pc->c1);
1174                 sp_canvas_item_hide(pc->cl0);
1175                 sp_canvas_item_hide(pc->cl1);
1176                 pc->state = SP_PEN_CONTEXT_POINT;
1177                 spdc_pen_set_subsequent_point(pc, pt, true);
1178                 pen_last_paraxial_dir = !pen_last_paraxial_dir;
1179                 ret = TRUE;
1180             }
1181             break;
1182         default:
1183             break;
1184     }
1185     return ret;
1186 }
1187
1188 static void
1189 spdc_reset_colors(SPPenContext *pc)
1190 {
1191     /* Red */
1192     pc->red_curve->reset();
1193     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), NULL);
1194     /* Blue */
1195     pc->blue_curve->reset();
1196     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->blue_bpath), NULL);
1197     /* Green */
1198     while (pc->green_bpaths) {
1199         gtk_object_destroy(GTK_OBJECT(pc->green_bpaths->data));
1200         pc->green_bpaths = g_slist_remove(pc->green_bpaths, pc->green_bpaths->data);
1201     }
1202     pc->green_curve->reset();
1203     if (pc->green_anchor) {
1204         pc->green_anchor = sp_draw_anchor_destroy(pc->green_anchor);
1205     }
1206     pc->sa = NULL;
1207     pc->ea = NULL;
1208     pc->npoints = 0;
1209     pc->red_curve_is_valid = false;
1210 }
1211
1212
1213 static void
1214 spdc_pen_set_initial_point(SPPenContext *const pc, Geom::Point const p)
1215 {
1216     g_assert( pc->npoints == 0 );
1217
1218     pc->p[0] = p;
1219     pc->p[1] = p;
1220     pc->npoints = 2;
1221     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), NULL);
1222
1223     sp_canvas_force_full_redraw_after_interruptions(pc->desktop->canvas, 5);
1224 }
1225
1226 /**
1227  * Show the status message for the current line/curve segment.
1228  * This type of message always shows angle/distance as the last
1229  * two parameters ("angle %3.2f&#176;, distance %s").
1230  */
1231 static void
1232 spdc_pen_set_angle_distance_status_message(SPPenContext *const pc, Geom::Point const p, int pc_point_to_compare, gchar const *message)
1233 {
1234     g_assert(pc != NULL);
1235     g_assert((pc_point_to_compare == 0) || (pc_point_to_compare == 3)); // exclude control handles
1236     g_assert(message != NULL);
1237
1238     SPDesktop *desktop = SP_EVENT_CONTEXT(pc)->desktop;
1239     Geom::Point rel = p - pc->p[pc_point_to_compare];
1240     GString *dist = SP_PX_TO_METRIC_STRING(Geom::L2(rel), desktop->namedview->getDefaultMetric());
1241     double angle = atan2(rel[Geom::Y], rel[Geom::X]) * 180 / M_PI;
1242     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
1243     if (prefs->getBool("/options/compassangledisplay/value", 0) != 0)
1244         angle = angle_to_compass (angle);
1245
1246     pc->_message_context->setF(Inkscape::IMMEDIATE_MESSAGE, message, angle, dist->str);
1247     g_string_free(dist, FALSE);
1248 }
1249
1250 static void
1251 spdc_pen_set_subsequent_point(SPPenContext *const pc, Geom::Point const p, bool statusbar, guint status)
1252 {
1253     g_assert( pc->npoints != 0 );
1254     /* todo: Check callers to see whether 2 <= npoints is guaranteed. */
1255
1256     pc->p[2] = p;
1257     pc->p[3] = p;
1258     pc->p[4] = p;
1259     pc->npoints = 5;
1260     pc->red_curve->reset();
1261     bool is_curve;
1262     pc->red_curve->moveto(pc->p[0]);
1263     if (pc->polylines_paraxial && !statusbar) {
1264         // we are drawing horizontal/vertical lines and hit an anchor;
1265         Geom::Point const origin = pc->p[0];
1266         // if the previous point and the anchor are not aligned either horizontally or vertically...
1267         if ((abs(p[Geom::X] - origin[Geom::X]) > 1e-9) && (abs(p[Geom::Y] - origin[Geom::Y]) > 1e-9)) {
1268             // ...then we should draw an L-shaped path, consisting of two paraxial segments
1269             Geom::Point intermed = p;
1270             pen_set_to_nearest_horiz_vert(pc, intermed, status, false);
1271             pc->red_curve->lineto(intermed);
1272         }
1273         pc->red_curve->lineto(p);
1274         is_curve = false;
1275     } else {
1276         // one of the 'regular' modes
1277         if (pc->p[1] != pc->p[0]) {
1278             pc->red_curve->curveto(pc->p[1], p, p);
1279             is_curve = true;
1280         } else {
1281             pc->red_curve->lineto(p);
1282             is_curve = false;
1283         }
1284     }
1285
1286     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
1287
1288     if (statusbar) {
1289         gchar *message = is_curve ?
1290             _("<b>Curve segment</b>: angle %3.2f&#176;, distance %s; with <b>Ctrl</b> to snap angle, <b>Enter</b> to finish the path" ):
1291             _("<b>Line segment</b>: angle %3.2f&#176;, distance %s; with <b>Ctrl</b> to snap angle, <b>Enter</b> to finish the path");
1292         spdc_pen_set_angle_distance_status_message(pc, p, 0, message);
1293     }
1294 }
1295
1296 static void
1297 spdc_pen_set_ctrl(SPPenContext *const pc, Geom::Point const p, guint const state)
1298 {
1299     sp_canvas_item_show(pc->c1);
1300     sp_canvas_item_show(pc->cl1);
1301
1302     if ( pc->npoints == 2 ) {
1303         pc->p[1] = p;
1304         sp_canvas_item_hide(pc->c0);
1305         sp_canvas_item_hide(pc->cl0);
1306         SP_CTRL(pc->c1)->moveto(pc->p[1]);
1307         sp_ctrlline_set_coords(SP_CTRLLINE(pc->cl1), pc->p[0], pc->p[1]);
1308
1309         spdc_pen_set_angle_distance_status_message(pc, p, 0, _("<b>Curve handle</b>: angle %3.2f&#176;, length %s; with <b>Ctrl</b> to snap angle"));
1310     } else if ( pc->npoints == 5 ) {
1311         pc->p[4] = p;
1312         sp_canvas_item_show(pc->c0);
1313         sp_canvas_item_show(pc->cl0);
1314         bool is_symm = false;
1315         if ( ( ( pc->mode == SP_PEN_CONTEXT_MODE_CLICK ) && ( state & GDK_CONTROL_MASK ) ) ||
1316              ( ( pc->mode == SP_PEN_CONTEXT_MODE_DRAG ) &&  !( state & GDK_SHIFT_MASK  ) ) ) {
1317             Geom::Point delta = p - pc->p[3];
1318             pc->p[2] = pc->p[3] - delta;
1319             is_symm = true;
1320             pc->red_curve->reset();
1321             pc->red_curve->moveto(pc->p[0]);
1322             pc->red_curve->curveto(pc->p[1], pc->p[2], pc->p[3]);
1323             sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
1324         }
1325         SP_CTRL(pc->c0)->moveto(pc->p[2]);
1326         sp_ctrlline_set_coords(SP_CTRLLINE(pc->cl0), pc->p[3], pc->p[2]);
1327         SP_CTRL(pc->c1)->moveto(pc->p[4]);
1328         sp_ctrlline_set_coords(SP_CTRLLINE(pc->cl1), pc->p[3], pc->p[4]);
1329
1330         gchar *message = is_symm ?
1331             _("<b>Curve handle, symmetric</b>: angle %3.2f&#176;, length %s; with <b>Ctrl</b> to snap angle, with <b>Shift</b> to move this handle only") :
1332             _("<b>Curve handle</b>: angle %3.2f&#176;, length %s; with <b>Ctrl</b> to snap angle, with <b>Shift</b> to move this handle only");
1333         spdc_pen_set_angle_distance_status_message(pc, p, 3, message);
1334     } else {
1335         g_warning("Something bad happened - npoints is %d", pc->npoints);
1336     }
1337 }
1338
1339 static void
1340 spdc_pen_finish_segment(SPPenContext *const pc, Geom::Point const p, guint const state)
1341 {
1342     if (pc->polylines_paraxial) {
1343         pen_last_paraxial_dir = pen_next_paraxial_direction(pc, p, pc->p[0], state);
1344     }
1345
1346     ++pc->num_clicks;
1347
1348     if (!pc->red_curve->is_empty()) {
1349         pc->green_curve->append_continuous(pc->red_curve, 0.0625);
1350         SPCurve *curve = pc->red_curve->copy();
1351         /// \todo fixme:
1352         SPCanvasItem *cshape = sp_canvas_bpath_new(sp_desktop_sketch(pc->desktop), curve);
1353         curve->unref();
1354         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cshape), pc->green_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1355
1356         pc->green_bpaths = g_slist_prepend(pc->green_bpaths, cshape);
1357
1358         pc->p[0] = pc->p[3];
1359         pc->p[1] = pc->p[4];
1360         pc->npoints = 2;
1361
1362         pc->red_curve->reset();
1363     }
1364 }
1365
1366 static void
1367 spdc_pen_finish(SPPenContext *const pc, gboolean const closed)
1368 {
1369     if (pc->expecting_clicks_for_LPE > 1) {
1370         // don't let the path be finished before we have collected the required number of mouse clicks
1371         return;
1372     }
1373
1374     pc->num_clicks = 0;
1375
1376     pen_disable_events(pc);
1377
1378     SPDesktop *const desktop = pc->desktop;
1379     pc->_message_context->clear();
1380     desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Drawing finished"));
1381
1382     pc->red_curve->reset();
1383     spdc_concat_colors_and_flush(pc, closed);
1384     pc->sa = NULL;
1385     pc->ea = NULL;
1386
1387     pc->npoints = 0;
1388     pc->state = SP_PEN_CONTEXT_POINT;
1389
1390     sp_canvas_item_hide(pc->c0);
1391     sp_canvas_item_hide(pc->c1);
1392     sp_canvas_item_hide(pc->cl0);
1393     sp_canvas_item_hide(pc->cl1);
1394
1395     if (pc->green_anchor) {
1396         pc->green_anchor = sp_draw_anchor_destroy(pc->green_anchor);
1397     }
1398
1399
1400     sp_canvas_end_forced_full_redraws(pc->desktop->canvas);
1401
1402     pen_enable_events(pc);
1403 }
1404
1405 static void
1406 pen_disable_events(SPPenContext *const pc) {
1407   pc->events_disabled++;
1408 }
1409
1410 static void
1411 pen_enable_events(SPPenContext *const pc) {
1412   g_return_if_fail(pc->events_disabled != 0);
1413
1414   pc->events_disabled--;
1415 }
1416
1417 void
1418 sp_pen_context_wait_for_LPE_mouse_clicks(SPPenContext *pc, Inkscape::LivePathEffect::EffectType effect_type,
1419                                          unsigned int num_clicks, bool use_polylines)
1420 {
1421     if (effect_type == Inkscape::LivePathEffect::INVALID_LPE)
1422         return;
1423
1424     pc->waiting_LPE_type = effect_type;
1425     pc->expecting_clicks_for_LPE = num_clicks;
1426     pc->polylines_only = use_polylines;
1427     pc->polylines_paraxial = false; // TODO: think if this is correct for all cases
1428 }
1429
1430 void
1431 sp_pen_context_cancel_waiting_for_LPE(SPPenContext *pc)
1432 {
1433     pc->waiting_LPE_type = Inkscape::LivePathEffect::INVALID_LPE;
1434     pc->expecting_clicks_for_LPE = 0;
1435     sp_pen_context_set_polyline_mode(pc);
1436 }
1437
1438 static int pen_next_paraxial_direction(const SPPenContext *const pc,
1439                                        Geom::Point const &pt, Geom::Point const &origin, guint state) {
1440     /*
1441      * after the first mouse click we determine whether the mouse pointer is closest to a
1442      * horizontal or vertical segment; for all subsequent mouse clicks, we use the direction
1443      * orthogonal to the last one; pressing Shift toggles the direction
1444      */
1445     // num_clicks is not reliable because spdc_pen_finish_segment is sometimes called too early
1446     // (on first mouse release), in which case num_clicks immediately becomes 1.
1447     // if (pc->num_clicks == 0) {
1448
1449     if (pc->green_curve->is_empty()) {
1450         // first mouse click
1451         double dist_h = fabs(pt[Geom::X] - origin[Geom::X]);
1452         double dist_v = fabs(pt[Geom::Y] - origin[Geom::Y]);
1453         int ret = (dist_h < dist_v) ? 1 : 0; // 0 = horizontal, 1 = vertical
1454         pen_last_paraxial_dir = (state & GDK_SHIFT_MASK) ? 1 - ret : ret;
1455         return pen_last_paraxial_dir;
1456     } else {
1457         // subsequent mouse click
1458         return (state & GDK_SHIFT_MASK) ? pen_last_paraxial_dir : 1 - pen_last_paraxial_dir;
1459     }
1460 }
1461
1462 void pen_set_to_nearest_horiz_vert(const SPPenContext *const pc, Geom::Point &pt, guint const state, bool snap)
1463 {
1464     Geom::Point const origin = pc->p[0];
1465
1466     int next_dir = pen_next_paraxial_direction(pc, pt, origin, state);
1467
1468     if (!snap) {
1469         if (next_dir == 0) {
1470             // line is forced to be horizontal
1471             pt[Geom::Y] = origin[Geom::Y];
1472         } else {
1473             // line is forced to be vertical
1474             pt[Geom::X] = origin[Geom::X];
1475         }
1476     } else {
1477         // Create a horizontal or vertical constraint line
1478         Inkscape::Snapper::SnapConstraint cl(origin, next_dir ? Geom::Point(0, 1) : Geom::Point(1, 0));
1479
1480         // Snap along the constraint line; if we didn't snap then still the constraint will be applied
1481         SnapManager &m = pc->desktop->namedview->snap_manager;
1482
1483         Inkscape::Selection *selection = sp_desktop_selection (pc->desktop);
1484         // selection->singleItem() is the item that is currently being drawn. This item will not be snapped to (to avoid self-snapping)
1485         // TODO: Allow snapping to the stationary parts of the item, and only ignore the last segment
1486
1487         m.setup(pc->desktop, true, selection->singleItem());
1488         m.constrainedSnapReturnByRef(pt, Inkscape::SNAPSOURCE_NODE_HANDLE, cl);
1489         m.unSetup();
1490     }
1491 }
1492
1493 /*
1494   Local Variables:
1495   mode:c++
1496   c-file-style:"stroustrup"
1497   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1498   indent-tabs-mode:nil
1499   fill-column:99
1500   End:
1501 */
1502 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :