src/gradient-drag.cpp

   1 #define __GRADIENT_DRAG_C__
   2
   3 /*
   4  * On-canvas gradient dragging
   5  *
   6  * Authors:
   7  *   bulia byak <buliabyak@users.sf.net>
   8  *   Johan Engelen <j.b.c.engelen@ewi.utwente.nl>
   9  *
  10  * Copyright (C) 2007 Johan Engelen
  11  * Copyright (C) 2005 Authors
  12  *
  13  * Released under GNU GPL, read the file 'COPYING' for more information
  14  */
  15
  16 #ifdef HAVE_CONFIG_H
  17 #include "config.h"
  18 #endif
  19
  20 #include <glibmm/i18n.h>
  21 #include <cstring>
  22 #include <string>
  23
  24 #include "desktop-handles.h"
  25 #include "selection.h"
  26 #include "desktop.h"
  27 #include "desktop-style.h"
  28 #include "document.h"
  29 #include "display/sp-ctrlline.h"
  30 #include "display/sp-canvas-util.h"
  31 #include "xml/repr.h"
  32 #include "svg/css-ostringstream.h"
  33 #include "svg/svg.h"
  34 #include "libnr/nr-point-fns.h"
  35 #include "preferences.h"
  36 #include "sp-item.h"
  37 #include "style.h"
  38 #include "knot.h"
  39 #include "sp-linear-gradient.h"
  40 #include "sp-radial-gradient.h"
  41 #include "gradient-chemistry.h"
  42 #include "gradient-drag.h"
  43 #include "sp-stop.h"
  44 #include "snap.h"
  45 #include "sp-namedview.h"
  46 #include "selection-chemistry.h"
  47
  48 #define GR_KNOT_COLOR_NORMAL 0xffffff00
  49 #define GR_KNOT_COLOR_MOUSEOVER 0xff000000
  50 #define GR_KNOT_COLOR_SELECTED 0x0000ff00
  51
  52 #define GR_LINE_COLOR_FILL 0x0000ff7f
  53 #define GR_LINE_COLOR_STROKE 0x9999007f
  54
  55 // screen pixels between knots when they snap:
  56 #define SNAP_DIST 5
  57
  58 // absolute distance between gradient points for them to become a single dragger when the drag is created:
  59 #define MERGE_DIST 0.1
  60
  61 // knot shapes corresponding to GrPointType enum
  62 SPKnotShapeType gr_knot_shapes [] = {
  63         SP_KNOT_SHAPE_SQUARE, //POINT_LG_BEGIN
  64         SP_KNOT_SHAPE_CIRCLE,  //POINT_LG_END
  65         SP_KNOT_SHAPE_DIAMOND, //POINT_LG_MID
  66         SP_KNOT_SHAPE_SQUARE,  // POINT_RG_CENTER
  67         SP_KNOT_SHAPE_CIRCLE,  // POINT_RG_R1
  68         SP_KNOT_SHAPE_CIRCLE,  // POINT_RG_R2
  69         SP_KNOT_SHAPE_CROSS, // POINT_RG_FOCUS
  70         SP_KNOT_SHAPE_DIAMOND, //POINT_RG_MID1
  71         SP_KNOT_SHAPE_DIAMOND //POINT_RG_MID2
  72 };
  73
  74 const gchar *gr_knot_descr [] = {
  75     N_("Linear gradient <b>start</b>"), //POINT_LG_BEGIN
  76     N_("Linear gradient <b>end</b>"),
  77     N_("Linear gradient <b>mid stop</b>"),
  78     N_("Radial gradient <b>center</b>"),
  79     N_("Radial gradient <b>radius</b>"),
  80     N_("Radial gradient <b>radius</b>"),
  81     N_("Radial gradient <b>focus</b>"), // POINT_RG_FOCUS
  82     N_("Radial gradient <b>mid stop</b>"),
  83     N_("Radial gradient <b>mid stop</b>")
  84 };
  85
  86 static void
  87 gr_drag_sel_changed(Inkscape::Selection */*selection*/, gpointer data)
  88 {
  89     GrDrag *drag = (GrDrag *) data;
  90     drag->updateDraggers ();
  91     drag->updateLines ();
  92     drag->updateLevels ();
  93 }
  94
  95 static void
  96 gr_drag_sel_modified (Inkscape::Selection */*selection*/, guint /*flags*/, gpointer data)
  97 {
  98     GrDrag *drag = (GrDrag *) data;
  99     if (drag->local_change) {
 100         drag->local_change = false;
 101     } else {
 102         drag->updateDraggers ();
 103     }
 104     drag->updateLines ();
 105     drag->updateLevels ();
 106 }
 107
 108 /**
 109 When a _query_style_signal is received, check that \a property requests fill/stroke/opacity (otherwise
 110 skip), and fill the \a style with the averaged color of all draggables of the selected dragger, if
 111 any.
 112 */
 113 int
 114 gr_drag_style_query (SPStyle *style, int property, gpointer data)
 115 {
 116     GrDrag *drag = (GrDrag *) data;
 117
 118     if (property != QUERY_STYLE_PROPERTY_FILL && property != QUERY_STYLE_PROPERTY_STROKE && property != QUERY_STYLE_PROPERTY_MASTEROPACITY) {
 119         return QUERY_STYLE_NOTHING;
 120     }
 121
 122     if (!drag->selected) {
 123         return QUERY_STYLE_NOTHING;
 124     } else {
 125         int ret = QUERY_STYLE_NOTHING;
 126
 127         float cf[4];
 128         cf[0] = cf[1] = cf[2] = cf[3] = 0;
 129
 130         int count = 0;
 131
 132         for (GList *i = drag->selected; i != NULL; i = i->next) { // for all selected draggers
 133             GrDragger *d = (GrDragger *) i->data;
 134             for (GSList const* j = d->draggables; j != NULL; j = j->next) { // for all draggables of dragger
 135                 GrDraggable *draggable = (GrDraggable *) j->data;
 136
 137                 if (ret == QUERY_STYLE_NOTHING) {
 138                     ret = QUERY_STYLE_SINGLE;
 139                 } else if (ret == QUERY_STYLE_SINGLE) {
 140                     ret = QUERY_STYLE_MULTIPLE_AVERAGED;
 141                 }
 142
 143                 guint32 c = sp_item_gradient_stop_query_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 144                 cf[0] += SP_RGBA32_R_F (c);
 145                 cf[1] += SP_RGBA32_G_F (c);
 146                 cf[2] += SP_RGBA32_B_F (c);
 147                 cf[3] += SP_RGBA32_A_F (c);
 148
 149                 count ++;
 150             }
 151         }
 152
 153         if (count) {
 154             cf[0] /= count;
 155             cf[1] /= count;
 156             cf[2] /= count;
 157             cf[3] /= count;
 158
 159             // set both fill and stroke with our stop-color and stop-opacity
 160             style->fill.clear();
 161             style->fill.setColor( cf[0], cf[1], cf[2] );
 162             style->fill.set = TRUE;
 163             style->stroke.clear();
 164             style->stroke.setColor( cf[0], cf[1], cf[2] );
 165             style->stroke.set = TRUE;
 166
 167             style->fill_opacity.value = SP_SCALE24_FROM_FLOAT (1.0);
 168             style->fill_opacity.set = TRUE;
 169             style->stroke_opacity.value = SP_SCALE24_FROM_FLOAT (1.0);
 170             style->stroke_opacity.set = TRUE;
 171
 172             style->opacity.value = SP_SCALE24_FROM_FLOAT (cf[3]);
 173             style->opacity.set = TRUE;
 174         }
 175
 176         return ret;
 177     }
 178 }
 179
 180 bool
 181 gr_drag_style_set (const SPCSSAttr *css, gpointer data)
 182 {
 183     GrDrag *drag = (GrDrag *) data;
 184
 185     if (!drag->selected)
 186         return false;
 187
 188     SPCSSAttr *stop = sp_repr_css_attr_new ();
 189
 190     // See if the css contains interesting properties, and if so, translate them into the format
 191     // acceptable for gradient stops
 192
 193     // any of color properties, in order of increasing priority:
 194     if (css->attribute("flood-color"))
 195         sp_repr_css_set_property (stop, "stop-color", css->attribute("flood-color"));
 196
 197     if (css->attribute("lighting-color"))
 198         sp_repr_css_set_property (stop, "stop-color", css->attribute("lighting-color"));
 199
 200     if (css->attribute("color"))
 201         sp_repr_css_set_property (stop, "stop-color", css->attribute("color"));
 202
 203     if (css->attribute("stroke") && strcmp(css->attribute("stroke"), "none"))
 204         sp_repr_css_set_property (stop, "stop-color", css->attribute("stroke"));
 205
 206     if (css->attribute("fill") && strcmp(css->attribute("fill"), "none"))
 207         sp_repr_css_set_property (stop, "stop-color", css->attribute("fill"));
 208
 209     if (css->attribute("stop-color"))
 210         sp_repr_css_set_property (stop, "stop-color", css->attribute("stop-color"));
 211
 212
 213     if (css->attribute("stop-opacity")) { // direct setting of stop-opacity has priority
 214         sp_repr_css_set_property (stop, "stop-opacity", css->attribute("stop-opacity"));
 215     } else {  // multiply all opacity properties:
 216         gdouble accumulated = 1.0;
 217         accumulated *= sp_svg_read_percentage(css->attribute("flood-opacity"), 1.0);
 218         accumulated *= sp_svg_read_percentage(css->attribute("opacity"), 1.0);
 219         accumulated *= sp_svg_read_percentage(css->attribute("stroke-opacity"), 1.0);
 220         accumulated *= sp_svg_read_percentage(css->attribute("fill-opacity"), 1.0);
 221
 222         Inkscape::CSSOStringStream os;
 223         os << accumulated;
 224         sp_repr_css_set_property (stop, "stop-opacity", os.str().c_str());
 225
 226         if ((css->attribute("fill") && !css->attribute("stroke") && !strcmp(css->attribute("fill"), "none")) ||
 227             (css->attribute("stroke") && !css->attribute("fill") && !strcmp(css->attribute("stroke"), "none")))
 228             sp_repr_css_set_property (stop, "stop-opacity", "0"); // if a single fill/stroke property is set to none, don't change color, set opacity to 0
 229     }
 230
 231     if (!stop->attributeList()) { // nothing for us here, pass it on
 232         sp_repr_css_attr_unref(stop);
 233         return false;
 234     }
 235
 236     for (GList const* sel = drag->selected; sel != NULL; sel = sel->next) { // for all selected draggers
 237         GrDragger* dragger = (GrDragger*) sel->data;
 238         for (GSList const* i = dragger->draggables; i != NULL; i = i->next) { // for all draggables of dragger
 239                GrDraggable *draggable = (GrDraggable *) i->data;
 240
 241                drag->local_change = true;
 242                sp_item_gradient_stop_set_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke, stop);
 243         }
 244     }
 245
 246     //sp_repr_css_print(stop);
 247     sp_repr_css_attr_unref(stop);
 248     return true;
 249 }
 250
 251 guint32 GrDrag::getColor()
 252 {
 253     if (!selected) return 0;
 254
 255     float cf[4];
 256     cf[0] = cf[1] = cf[2] = cf[3] = 0;
 257
 258     int count = 0;
 259
 260     for (GList *i = selected; i != NULL; i = i->next) { // for all selected draggers
 261         GrDragger *d = (GrDragger *) i->data;
 262         for (GSList const* j = d->draggables; j != NULL; j = j->next) { // for all draggables of dragger
 263             GrDraggable *draggable = (GrDraggable *) j->data;
 264
 265             guint32 c = sp_item_gradient_stop_query_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 266             cf[0] += SP_RGBA32_R_F (c);
 267             cf[1] += SP_RGBA32_G_F (c);
 268             cf[2] += SP_RGBA32_B_F (c);
 269             cf[3] += SP_RGBA32_A_F (c);
 270
 271             count ++;
 272         }
 273     }
 274
 275     if (count) {
 276         cf[0] /= count;
 277         cf[1] /= count;
 278         cf[2] /= count;
 279         cf[3] /= count;
 280     }
 281
 282     return SP_RGBA32_F_COMPOSE(cf[0], cf[1], cf[2], cf[3]);
 283 }
 284
 285 SPStop *
 286 GrDrag::addStopNearPoint (SPItem *item, Geom::Point mouse_p, double tolerance)
 287 {
 288     gfloat offset; // type of SPStop.offset = gfloat
 289     SPGradient *gradient;
 290     bool fill_or_stroke = true;
 291     bool r1_knot = false;
 292
 293     bool addknot = false;
 294     do {
 295         gradient = sp_item_gradient (item, fill_or_stroke);
 296         if (SP_IS_LINEARGRADIENT(gradient)) {
 297             Geom::Point begin   = sp_item_gradient_get_coords(item, POINT_LG_BEGIN, 0, fill_or_stroke);
 298             Geom::Point end     = sp_item_gradient_get_coords(item, POINT_LG_END, 0, fill_or_stroke);
 299
 300             Geom::Point nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 301             double dist_screen = Geom::L2 (mouse_p - nearest);
 302             if ( dist_screen < tolerance ) {
 303                 // add the knot
 304                 offset = get_offset_between_points(nearest, begin, end);
 305                 addknot = true;
 306                 break; // break out of the while loop: add only one knot
 307             }
 308         } else if (SP_IS_RADIALGRADIENT(gradient)) {
 309             Geom::Point begin = sp_item_gradient_get_coords(item, POINT_RG_CENTER, 0, fill_or_stroke);
 310             Geom::Point end   = sp_item_gradient_get_coords(item, POINT_RG_R1, 0, fill_or_stroke);
 311             Geom::Point nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 312             double dist_screen = Geom::L2 (mouse_p - nearest);
 313             if ( dist_screen < tolerance ) {
 314                 offset = get_offset_between_points(nearest, begin, end);
 315                 addknot = true;
 316                 r1_knot = true;
 317                 break; // break out of the while loop: add only one knot
 318             }
 319
 320             end    = sp_item_gradient_get_coords(item, POINT_RG_R2, 0, fill_or_stroke);
 321             nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 322             dist_screen = Geom::L2 (mouse_p - nearest);
 323             if ( dist_screen < tolerance ) {
 324                 offset = get_offset_between_points(nearest, begin, end);
 325                 addknot = true;
 326                 r1_knot = false;
 327                 break; // break out of the while loop: add only one knot
 328             }
 329         }
 330         fill_or_stroke = !fill_or_stroke;
 331     } while (!fill_or_stroke && !addknot) ;
 332
 333     if (addknot) {
 334         SPGradient *vector = sp_gradient_get_forked_vector_if_necessary (gradient, false);
 335         SPStop* prev_stop = sp_first_stop(vector);
 336         SPStop* next_stop = sp_next_stop(prev_stop);
 337         guint i = 1;
 338         while ( (next_stop) && (next_stop->offset < offset) ) {
 339             prev_stop = next_stop;
 340             next_stop = sp_next_stop(next_stop);
 341             i++;
 342         }
 343         if (!next_stop) {
 344             // logical error: the endstop should have offset 1 and should always be more than this offset here
 345             return NULL;
 346         }
 347
 348
 349         SPStop *newstop = sp_vector_add_stop (vector, prev_stop, next_stop, offset);
 350         sp_gradient_ensure_vector (gradient);
 351         updateDraggers();
 352
 353         return newstop;
 354     }
 355
 356     return NULL;
 357 }
 358
 359
 360 bool
 361 GrDrag::dropColor(SPItem */*item*/, gchar const *c, Geom::Point p)
 362 {
 363     // first, see if we can drop onto one of the existing draggers
 364     for (GList *i = draggers; i != NULL; i = i->next) { // for all draggables of dragger
 365         GrDragger *d = (GrDragger *) i->data;
 366
 367         if (Geom::L2(p - d->point)*desktop->current_zoom() < 5) {
 368            SPCSSAttr *stop = sp_repr_css_attr_new ();
 369            sp_repr_css_set_property (stop, "stop-color", c);
 370            sp_repr_css_set_property (stop, "stop-opacity", "1");
 371            for (GSList *j = d->draggables; j != NULL; j = j->next) { // for all draggables of dragger
 372                GrDraggable *draggable = (GrDraggable *) j->data;
 373                local_change = true;
 374                sp_item_gradient_stop_set_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke, stop);
 375            }
 376            sp_repr_css_attr_unref(stop);
 377            return true;
 378         }
 379     }
 380
 381     // now see if we're over line and create a new stop
 382     bool over_line = false;
 383     SPCtrlLine *line = NULL;
 384     if (lines) {
 385         for (GSList *l = lines; (l != NULL) && (!over_line); l = l->next) {
 386             line = (SPCtrlLine*) l->data;
 387             Geom::Point nearest = snap_vector_midpoint (p, line->s, line->e, 0);
 388             double dist_screen = Geom::L2 (p - nearest) * desktop->current_zoom();
 389             if (line->item && dist_screen < 5) {
 390                 SPStop *stop = addStopNearPoint (line->item, p, 5/desktop->current_zoom());
 391                 if (stop) {
 392                     SPCSSAttr *css = sp_repr_css_attr_new ();
 393                     sp_repr_css_set_property (css, "stop-color", c);
 394                     sp_repr_css_set_property (css, "stop-opacity", "1");
 395                     sp_repr_css_change (SP_OBJECT_REPR (stop), css, "style");
 396                     return true;
 397                 }
 398             }
 399         }
 400     }
 401
 402     return false;
 403 }
 404
 405
 406 GrDrag::GrDrag(SPDesktop *desktop) {
 407
 408     this->desktop = desktop;
 409
 410     this->selection = sp_desktop_selection(desktop);
 411
 412     this->draggers = NULL;
 413     this->lines = NULL;
 414     this->selected = NULL;
 415
 416     this->hor_levels.clear();
 417     this->vert_levels.clear();
 418
 419     this->local_change = false;
 420
 421     this->sel_changed_connection = this->selection->connectChanged(
 422         sigc::bind (
 423             sigc::ptr_fun(&gr_drag_sel_changed),
 424             (gpointer)this )
 425
 426         );
 427     this->sel_modified_connection = this->selection->connectModified(
 428         sigc::bind(
 429             sigc::ptr_fun(&gr_drag_sel_modified),
 430             (gpointer)this )
 431         );
 432
 433     this->style_set_connection = this->desktop->connectSetStyle(
 434         sigc::bind(
 435             sigc::ptr_fun(&gr_drag_style_set),
 436             (gpointer)this )
 437         );
 438
 439     this->style_query_connection = this->desktop->connectQueryStyle(
 440         sigc::bind(
 441             sigc::ptr_fun(&gr_drag_style_query),
 442             (gpointer)this )
 443         );
 444
 445     this->updateDraggers ();
 446     this->updateLines ();
 447     this->updateLevels ();
 448
 449     if (desktop->gr_item) {
 450         this->setSelected (getDraggerFor (desktop->gr_item, desktop->gr_point_type, desktop->gr_point_i, desktop->gr_fill_or_stroke));
 451     }
 452 }
 453
 454 GrDrag::~GrDrag()
 455 {
 456     this->sel_changed_connection.disconnect();
 457     this->sel_modified_connection.disconnect();
 458     this->style_set_connection.disconnect();
 459     this->style_query_connection.disconnect();
 460
 461     if (this->selected) {
 462         GrDraggable *draggable = (GrDraggable *)   ((GrDragger*)this->selected->data)->draggables->data;
 463         desktop->gr_item = draggable->item;
 464         desktop->gr_point_type = draggable->point_type;
 465         desktop->gr_point_i = draggable->point_i;
 466         desktop->gr_fill_or_stroke = draggable->fill_or_stroke;
 467     } else {
 468         desktop->gr_item = NULL;
 469         desktop->gr_point_type = 0;
 470         desktop->gr_point_i = 0;
 471         desktop->gr_fill_or_stroke = true;
 472     }
 473
 474     deselect_all();
 475     for (GList *l = this->draggers; l != NULL; l = l->next) {
 476         delete ((GrDragger *) l->data);
 477     }
 478     g_list_free (this->draggers);
 479     this->draggers = NULL;
 480     this->selected = NULL;
 481
 482     for (GSList *l = this->lines; l != NULL; l = l->next) {
 483         gtk_object_destroy( GTK_OBJECT (l->data));
 484     }
 485     g_slist_free (this->lines);
 486     this->lines = NULL;
 487 }
 488
 489 GrDraggable::GrDraggable (SPItem *item, guint point_type, guint point_i, bool fill_or_stroke)
 490 {
 491     this->item = item;
 492     this->point_type = point_type;
 493     this->point_i = point_i;
 494     this->fill_or_stroke = fill_or_stroke;
 495
 496     g_object_ref (G_OBJECT (this->item));
 497 }
 498
 499 GrDraggable::~GrDraggable ()
 500 {
 501     g_object_unref (G_OBJECT (this->item));
 502 }
 503
 504
 505 SPObject *
 506 GrDraggable::getServer ()
 507 {
 508     if (!item)
 509         return NULL;
 510
 511     SPObject *server = NULL;
 512     if (fill_or_stroke)
 513         server = SP_OBJECT_STYLE_FILL_SERVER (item);
 514     else
 515         server = SP_OBJECT_STYLE_STROKE_SERVER (item);
 516
 517     return server;
 518 }
 519
 520 static
 521 boost::optional<Geom::Point>
 522 get_snap_vector (Geom::Point p, Geom::Point o, double snap, double initial)
 523 {
 524     double r = L2 (p - o);
 525     if (r < 1e-3) {
 526         return boost::optional<Geom::Point>();
 527     }
 528
 529     double angle = atan2 (p - o);
 530     // snap angle to snaps increments, starting from initial:
 531     double a_snapped = initial + floor((angle - initial)/snap + 0.5) * snap;
 532     // calculate the new position and subtract p to get the vector:
 533     return (o + r * Geom::Point(cos(a_snapped), sin(a_snapped)) - p);
 534 }
 535
 536 static void
 537 gr_knot_moved_handler(SPKnot *knot, Geom::Point const &ppointer, guint state, gpointer data)
 538 {
 539     GrDragger *dragger = (GrDragger *) data;
 540     GrDrag *drag = dragger->parent;
 541
 542     Geom::Point p = ppointer;
 543
 544     SPDesktop *desktop = dragger->parent->desktop;
 545         SnapManager &m = desktop->namedview->snap_manager;
 546         double snap_dist = m.snapprefs.getObjectTolerance() / dragger->parent->desktop->current_zoom();
 547
 548     if (state & GDK_SHIFT_MASK) {
 549         // with Shift; unsnap if we carry more than one draggable
 550         if (dragger->draggables && dragger->draggables->next) {
 551             // create a new dragger
 552             GrDragger *dr_new = new GrDragger (dragger->parent, dragger->point, NULL);
 553             dragger->parent->draggers = g_list_prepend (dragger->parent->draggers, dr_new);
 554             // relink to it all but the first draggable in the list
 555             for (GSList const* i = dragger->draggables->next; i != NULL; i = i->next) {
 556                 GrDraggable *draggable = (GrDraggable *) i->data;
 557                 dr_new->addDraggable (draggable);
 558             }
 559             dr_new->updateKnotShape();
 560             g_slist_free (dragger->draggables->next);
 561             dragger->draggables->next = NULL;
 562             dragger->updateKnotShape();
 563             dragger->updateTip();
 564         }
 565     } else if (!(state & GDK_CONTROL_MASK)) {
 566         // without Shift or Ctrl; see if we need to snap to another dragger
 567         for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 568             GrDragger *d_new = (GrDragger *) di->data;
 569             if (dragger->mayMerge(d_new) && Geom::L2 (d_new->point - p) < snap_dist) {
 570
 571                 // Merge draggers:
 572                 for (GSList const* i = dragger->draggables; i != NULL; i = i->next) { // for all draggables of dragger
 573                     GrDraggable *draggable = (GrDraggable *) i->data;
 574                     // copy draggable to d_new:
 575                     GrDraggable *da_new = new GrDraggable (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 576                     d_new->addDraggable (da_new);
 577                 }
 578
 579                 // unlink and delete this dragger
 580                 dragger->parent->draggers = g_list_remove (dragger->parent->draggers, dragger);
 581                 delete dragger;
 582
 583                 // update the new merged dragger
 584                 d_new->fireDraggables(true, false, true);
 585                 d_new->parent->updateLines();
 586                 d_new->parent->setSelected (d_new);
 587                 d_new->updateKnotShape ();
 588                 d_new->updateTip ();
 589                 d_new->updateDependencies(true);
 590                 sp_document_done (sp_desktop_document (d_new->parent->desktop), SP_VERB_CONTEXT_GRADIENT,
 591                                   _("Merge gradient handles"));
 592                 return;
 593             }
 594         }
 595     }
 596
 597     m.setup(desktop);
 598     if (!((state & GDK_SHIFT_MASK) || (state & GDK_CONTROL_MASK))) {
 599         Inkscape::SnappedPoint s = m.freeSnap(Inkscape::SnapPreferences::SNAPPOINT_OTHER, p, Inkscape::SNAPSOURCE_HANDLE);
 600         if (s.getSnapped()) {
 601             p = s.getPoint();
 602             sp_knot_moveto (knot, p);
 603         }
 604     } else if (state & GDK_CONTROL_MASK) {
 605         SnappedConstraints sc;
 606         Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 607         unsigned snaps = abs(prefs->getInt("/options/rotationsnapsperpi/value", 12));
 608         /* 0 means no snapping. */
 609
 610         for (GSList const* i = dragger->draggables; i != NULL; i = i->next) {
 611             GrDraggable *draggable = (GrDraggable *) i->data;
 612
 613             Geom::Point dr_snap(Geom::infinity(), Geom::infinity());
 614
 615             if (draggable->point_type == POINT_LG_BEGIN || draggable->point_type == POINT_LG_END) {
 616                 for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 617                     GrDragger *d_new = (GrDragger *) di->data;
 618                     if (d_new == dragger)
 619                         continue;
 620                     if (d_new->isA (draggable->item,
 621                                     draggable->point_type == POINT_LG_BEGIN? POINT_LG_END : POINT_LG_BEGIN,
 622                                     draggable->fill_or_stroke)) {
 623                         // found the other end of the linear gradient;
 624                         if (state & GDK_SHIFT_MASK) {
 625                             // moving linear around center
 626                             Geom::Point center = Geom::Point (0.5*(d_new->point + dragger->point));
 627                             dr_snap = center;
 628                         } else {
 629                             // moving linear around the other end
 630                             dr_snap = d_new->point;
 631                         }
 632                     }
 633                 }
 634             } else if (draggable->point_type == POINT_RG_R1 || draggable->point_type == POINT_RG_R2 || draggable->point_type == POINT_RG_FOCUS) {
 635                 for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 636                     GrDragger *d_new = (GrDragger *) di->data;
 637                     if (d_new == dragger)
 638                         continue;
 639                     if (d_new->isA (draggable->item,
 640                                     POINT_RG_CENTER,
 641                                     draggable->fill_or_stroke)) {
 642                         // found the center of the radial gradient;
 643                         dr_snap = d_new->point;
 644                     }
 645                 }
 646             } else if (draggable->point_type == POINT_RG_CENTER) {
 647                 // radial center snaps to hor/vert relative to its original position
 648                 dr_snap = dragger->point_original;
 649             }
 650
 651             boost::optional<Geom::Point> snap_vector;
 652             if (dr_snap.isFinite()) {
 653                 if (state & GDK_MOD1_MASK) {
 654                     // with Alt, snap to the original angle and its perpendiculars
 655                     snap_vector = get_snap_vector (p, dr_snap, M_PI/2, Geom::atan2 (dragger->point_original - dr_snap));
 656                 } else {
 657                     // with Ctrl, snap to M_PI/snaps
 658                     snap_vector = get_snap_vector (p, dr_snap, M_PI/snaps, 0);
 659                 }
 660                 if (snap_vector) {
 661                     Inkscape::Snapper::ConstraintLine cl(dr_snap, p + *snap_vector - dr_snap);
 662                     Inkscape::SnappedPoint s = m.constrainedSnap(Inkscape::SnapPreferences::SNAPPOINT_OTHER, p + *snap_vector, Inkscape::SNAPSOURCE_HANDLE, cl);
 663                     if (s.getSnapped()) {
 664                         s.setTransformation(s.getPoint() - p);
 665                         sc.points.push_back(s);
 666                     } else {
 667                         Inkscape::SnappedPoint dummy(p + *snap_vector, Inkscape::SNAPSOURCE_HANDLE, 0, Inkscape::SNAPTARGET_CONSTRAINED_ANGLE, Geom::L2(*snap_vector), 10000, true, false);
 668                         dummy.setTransformation(*snap_vector);
 669                         sc.points.push_back(dummy);
 670                     }
 671                 }
 672             }
 673         }
 674
 675         Inkscape::SnappedPoint bsp = m.findBestSnap(p, Inkscape::SNAPSOURCE_HANDLE, sc, true); // snap indicator will be displayed if needed
 676
 677         if (bsp.getSnapped()) {
 678             p += bsp.getTransformation();
 679             sp_knot_moveto (knot, p);
 680         }
 681     }
 682
 683     drag->keep_selection = (bool) g_list_find(drag->selected, dragger);
 684     bool scale_radial = (state & GDK_CONTROL_MASK) && (state & GDK_SHIFT_MASK);
 685
 686     if (drag->keep_selection) {
 687         Geom::Point diff = p - dragger->point;
 688         drag->selected_move_nowrite (diff[Geom::X], diff[Geom::Y], scale_radial);
 689     } else {
 690         dragger->point = p;
 691         dragger->fireDraggables (false, scale_radial);
 692         dragger->updateDependencies(false);
 693     }
 694
 695 }
 696
 697
 698 static void
 699 gr_midpoint_limits(GrDragger *dragger, SPObject *server, Geom::Point *begin, Geom::Point *end, Geom::Point *low_lim, Geom::Point *high_lim, GSList **moving)
 700 {
 701
 702     GrDrag *drag = dragger->parent;
 703     // a midpoint dragger can (logically) only contain one GrDraggable
 704     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 705
 706     // get begin and end points between which dragging is allowed:
 707     // the draglimits are between knot(lowest_i - 1) and knot(highest_i + 1)
 708     *moving = g_slist_append(*moving, dragger);
 709
 710     guint lowest_i = draggable->point_i;
 711     guint highest_i = draggable->point_i;
 712     GrDragger *lowest_dragger = dragger;
 713     GrDragger *highest_dragger = dragger;
 714     if (dragger->isSelected()) {
 715         GrDragger* d_add;
 716         while ( true )
 717         {
 718             d_add = drag->getDraggerFor(draggable->item, draggable->point_type, lowest_i - 1, draggable->fill_or_stroke);
 719             if ( d_add && g_list_find(drag->selected, d_add) ) {
 720                 lowest_i = lowest_i - 1;
 721                 *moving = g_slist_prepend(*moving, d_add);
 722                 lowest_dragger = d_add;
 723             } else {
 724                 break;
 725             }
 726         }
 727
 728         while ( true )
 729         {
 730             d_add = drag->getDraggerFor(draggable->item, draggable->point_type, highest_i + 1, draggable->fill_or_stroke);
 731             if ( d_add && g_list_find(drag->selected, d_add) ) {
 732                 highest_i = highest_i + 1;
 733                 *moving = g_slist_append(*moving, d_add);
 734                 highest_dragger = d_add;
 735             } else {
 736                 break;
 737             }
 738         }
 739     }
 740
 741     if ( SP_IS_LINEARGRADIENT(server) ) {
 742         guint num = SP_LINEARGRADIENT(server)->vector.stops.size();
 743         GrDragger *d_temp;
 744         if (lowest_i == 1) {
 745             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_BEGIN, 0, draggable->fill_or_stroke);
 746         } else {
 747             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_MID, lowest_i - 1, draggable->fill_or_stroke);
 748         }
 749         if (d_temp)
 750             *begin = d_temp->point;
 751
 752         d_temp = drag->getDraggerFor (draggable->item, POINT_LG_MID, highest_i + 1, draggable->fill_or_stroke);
 753         if (d_temp == NULL) {
 754             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_END, num-1, draggable->fill_or_stroke);
 755         }
 756         if (d_temp)
 757             *end = d_temp->point;
 758     } else if ( SP_IS_RADIALGRADIENT(server) ) {
 759         guint num = SP_RADIALGRADIENT(server)->vector.stops.size();
 760         GrDragger *d_temp;
 761         if (lowest_i == 1) {
 762             d_temp = drag->getDraggerFor (draggable->item, POINT_RG_CENTER, 0, draggable->fill_or_stroke);
 763         } else {
 764             d_temp = drag->getDraggerFor (draggable->item, draggable->point_type, lowest_i - 1, draggable->fill_or_stroke);
 765         }
 766         if (d_temp)
 767             *begin = d_temp->point;
 768
 769         d_temp = drag->getDraggerFor (draggable->item, draggable->point_type, highest_i + 1, draggable->fill_or_stroke);
 770         if (d_temp == NULL) {
 771             d_temp = drag->getDraggerFor (draggable->item, (draggable->point_type==POINT_RG_MID1) ? POINT_RG_R1 : POINT_RG_R2, num-1, draggable->fill_or_stroke);
 772         }
 773         if (d_temp)
 774             *end = d_temp->point;
 775     }
 776
 777     *low_lim  = dragger->point - (lowest_dragger->point - *begin);
 778     *high_lim = dragger->point - (highest_dragger->point - *end);
 779 }
 780
 781
 782
 783 /**
 784 Called when a midpoint knot is dragged.
 785 */
 786 static void
 787 gr_knot_moved_midpoint_handler(SPKnot */*knot*/, Geom::Point const &ppointer, guint state, gpointer data)
 788 {
 789     GrDragger *dragger = (GrDragger *) data;
 790     GrDrag *drag = dragger->parent;
 791     // a midpoint dragger can (logically) only contain one GrDraggable
 792     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 793
 794     // FIXME: take from prefs
 795     double snap_fraction = 0.1;
 796
 797     Geom::Point p = ppointer;
 798     Geom::Point begin(0,0), end(0,0);
 799     Geom::Point low_lim(0,0), high_lim(0,0);
 800
 801     SPObject *server = draggable->getServer();
 802
 803     GSList *moving = NULL;
 804     gr_midpoint_limits(dragger, server, &begin, &end, &low_lim, &high_lim, &moving);
 805
 806     if (state & GDK_CONTROL_MASK) {
 807         p = snap_vector_midpoint (p, low_lim, high_lim, snap_fraction);
 808     } else {
 809         p = snap_vector_midpoint (p, low_lim, high_lim, 0);
 810     }
 811     Geom::Point displacement = p - dragger->point;
 812
 813     for (GSList const* i = moving; i != NULL; i = i->next) {
 814         GrDragger *drg = (GrDragger*) i->data;
 815         SPKnot *drgknot = drg->knot;
 816         Geom::Point this_move = displacement;
 817         if (state & GDK_MOD1_MASK) {
 818             // FIXME: unify all these profiles (here, in nodepath, in tweak) in one place
 819             double alpha = 1.0;
 820             if (Geom::L2(drg->point - dragger->point) + Geom::L2(drg->point - begin) - 1e-3 > Geom::L2(dragger->point - begin)) { // drg is on the end side from dragger
 821                 double x = Geom::L2(drg->point - dragger->point)/Geom::L2(end - dragger->point);
 822                 this_move = (0.5 * cos (M_PI * (pow(x, alpha))) + 0.5) * this_move;
 823             } else { // drg is on the begin side from dragger
 824                 double x = Geom::L2(drg->point - dragger->point)/Geom::L2(begin - dragger->point);
 825                 this_move = (0.5 * cos (M_PI * (pow(x, alpha))) + 0.5) * this_move;
 826             }
 827         }
 828         drg->point += this_move;
 829         sp_knot_moveto (drgknot, drg->point);
 830         drg->fireDraggables (false);
 831         drg->updateDependencies(false);
 832     }
 833
 834     g_slist_free(moving);
 835
 836     drag->keep_selection = dragger->isSelected();
 837 }
 838
 839
 840
 841 static void
 842 gr_knot_grabbed_handler (SPKnot */*knot*/, unsigned int /*state*/, gpointer data)
 843 {
 844     GrDragger *dragger = (GrDragger *) data;
 845
 846     sp_canvas_force_full_redraw_after_interruptions(dragger->parent->desktop->canvas, 5);
 847 }
 848
 849 /**
 850 Called when the mouse releases a dragger knot; changes gradient writing to repr, updates other draggers if needed
 851 */
 852 static void
 853 gr_knot_ungrabbed_handler (SPKnot *knot, unsigned int state, gpointer data)
 854 {
 855     GrDragger *dragger = (GrDragger *) data;
 856
 857     sp_canvas_end_forced_full_redraws(dragger->parent->desktop->canvas);
 858
 859     dragger->point_original = dragger->point = knot->pos;
 860
 861     if ((state & GDK_CONTROL_MASK) && (state & GDK_SHIFT_MASK)) {
 862         dragger->fireDraggables (true, true);
 863     } else {
 864         dragger->fireDraggables (true);
 865     }
 866
 867     for (GList *i = dragger->parent->selected; i != NULL; i = i->next) {
 868         GrDragger *d = (GrDragger *) i->data;
 869         if (d == dragger)
 870             continue;
 871         d->fireDraggables (true);
 872     }
 873
 874     // make this dragger selected
 875     if (!dragger->parent->keep_selection) {
 876         dragger->parent->setSelected (dragger);
 877     }
 878     dragger->parent->keep_selection = false;
 879
 880     dragger->updateDependencies(true);
 881
 882     // we did an undoable action
 883     sp_document_done (sp_desktop_document (dragger->parent->desktop), SP_VERB_CONTEXT_GRADIENT,
 884                       _("Move gradient handle"));
 885 }
 886
 887 /**
 888 Called when a dragger knot is clicked; selects the dragger or deletes it depending on the
 889 state of the keyboard keys
 890 */
 891 static void
 892 gr_knot_clicked_handler(SPKnot */*knot*/, guint state, gpointer data)
 893 {
 894     GrDragger *dragger = (GrDragger *) data;
 895     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 896     if (!draggable) return;
 897
 898     if ( (state & GDK_CONTROL_MASK) && (state & GDK_MOD1_MASK ) ) {
 899     // delete this knot from vector
 900         SPGradient *gradient = sp_item_gradient (draggable->item, draggable->fill_or_stroke);
 901         gradient = sp_gradient_get_vector (gradient, false);
 902         if (gradient->vector.stops.size() > 2) { // 2 is the minimum
 903                 SPStop *stop = NULL;
 904                 switch (draggable->point_type) {  // if we delete first or last stop, move the next/previous to the edge
 905                 case POINT_LG_BEGIN:
 906                 case POINT_RG_CENTER:
 907                     stop = sp_first_stop(gradient);
 908                         {
 909                             SPStop *next = sp_next_stop (stop);
 910                                 if (next) {
 911                                         next->offset = 0;
 912                                         sp_repr_set_css_double (SP_OBJECT_REPR (next), "offset", 0);
 913                                 }
 914                         }
 915                     break;
 916                 case POINT_LG_END:
 917                 case POINT_RG_R1:
 918                 case POINT_RG_R2:
 919                     stop = sp_last_stop(gradient);
 920                     {
 921                             SPStop *prev = sp_prev_stop (stop, gradient);
 922                             if (prev) {
 923                                     prev->offset = 1;
 924                                     sp_repr_set_css_double (SP_OBJECT_REPR (prev), "offset", 1);
 925                             }
 926                         }
 927                     break;
 928                 case POINT_LG_MID:
 929                 case POINT_RG_MID1:
 930                 case POINT_RG_MID2:
 931                     stop = sp_get_stop_i(gradient, draggable->point_i);
 932                     break;
 933                 }
 934
 935                 SP_OBJECT_REPR(gradient)->removeChild(SP_OBJECT_REPR(stop));
 936                 sp_document_done (SP_OBJECT_DOCUMENT (gradient), SP_VERB_CONTEXT_GRADIENT,
 937                                   _("Delete gradient stop"));
 938         }
 939     } else {
 940     // select the dragger
 941         dragger->point_original = dragger->point;
 942
 943         if ( state & GDK_SHIFT_MASK ) {
 944             dragger->parent->setSelected (dragger, true, false);
 945         } else {
 946             dragger->parent->setSelected (dragger);
 947         }
 948     }
 949 }
 950
 951 /**
 952 Called when a dragger knot is doubleclicked; opens gradient editor with the stop from the first draggable
 953 */
 954 static void
 955 gr_knot_doubleclicked_handler (SPKnot */*knot*/, guint /*state*/, gpointer data)
 956 {
 957     GrDragger *dragger = (GrDragger *) data;
 958
 959     dragger->point_original = dragger->point;
 960
 961     if (dragger->draggables == NULL)
 962         return;
 963
 964     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 965     sp_item_gradient_edit_stop (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 966 }
 967
 968 /**
 969 Act upon all draggables of the dragger, setting them to the dragger's point
 970 */
 971 void
 972 GrDragger::fireDraggables (bool write_repr, bool scale_radial, bool merging_focus)
 973 {
 974     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
 975         GrDraggable *draggable = (GrDraggable *) i->data;
 976
 977         // set local_change flag so that selection_changed callback does not regenerate draggers
 978         this->parent->local_change = true;
 979
 980         // change gradient, optionally writing to repr; prevent focus from moving if it's snapped
 981         // to the center, unless it's the first update upon merge when we must snap it to the point
 982         if (merging_focus ||
 983             !(draggable->point_type == POINT_RG_FOCUS && this->isA(draggable->item, POINT_RG_CENTER, draggable->point_i, draggable->fill_or_stroke)))
 984         {
 985             sp_item_gradient_set_coords (draggable->item, draggable->point_type, draggable->point_i, this->point, draggable->fill_or_stroke, write_repr, scale_radial);
 986         }
 987     }
 988 }
 989
 990 /**
 991 Checks if the dragger has a draggable with this point_type
 992  */
 993 bool
 994 GrDragger::isA (gint point_type)
 995 {
 996     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
 997         GrDraggable *draggable = (GrDraggable *) i->data;
 998         if (draggable->point_type == point_type) {
 999             return true;
1000         }
1001     }
1002     return false;
1003 }
1004
1005 /**
1006 Checks if the dragger has a draggable with this item, point_type + point_i (number), fill_or_stroke
1007  */
1008 bool
1009 GrDragger::isA (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke)
1010 {
1011     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1012         GrDraggable *draggable = (GrDraggable *) i->data;
1013         if ( (draggable->point_type == point_type) && (draggable->point_i == point_i) && (draggable->item == item) && (draggable->fill_or_stroke == fill_or_stroke) ) {
1014             return true;
1015         }
1016     }
1017     return false;
1018 }
1019
1020 /**
1021 Checks if the dragger has a draggable with this item, point_type, fill_or_stroke
1022  */
1023 bool
1024 GrDragger::isA (SPItem *item, gint point_type, bool fill_or_stroke)
1025 {
1026     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1027         GrDraggable *draggable = (GrDraggable *) i->data;
1028         if ( (draggable->point_type == point_type) && (draggable->item == item) && (draggable->fill_or_stroke == fill_or_stroke) ) {
1029             return true;
1030         }
1031     }
1032     return false;
1033 }
1034
1035 bool
1036 GrDraggable::mayMerge (GrDraggable *da2)
1037 {
1038     if ((this->item == da2->item) && (this->fill_or_stroke == da2->fill_or_stroke)) {
1039         // we must not merge the points of the same gradient!
1040         if (!((this->point_type == POINT_RG_FOCUS && da2->point_type == POINT_RG_CENTER) ||
1041               (this->point_type == POINT_RG_CENTER && da2->point_type == POINT_RG_FOCUS))) {
1042             // except that we can snap center and focus together
1043             return false;
1044         }
1045     }
1046     // disable merging of midpoints.
1047     if ( (this->point_type == POINT_LG_MID) || (da2->point_type == POINT_LG_MID)
1048          || (this->point_type == POINT_RG_MID1) || (da2->point_type == POINT_RG_MID1)
1049          || (this->point_type == POINT_RG_MID2) || (da2->point_type == POINT_RG_MID2) )
1050         return false;
1051
1052     return true;
1053 }
1054
1055 bool
1056 GrDragger::mayMerge (GrDragger *other)
1057 {
1058     if (this == other)
1059         return false;
1060
1061     for (GSList const* i = this->draggables; i != NULL; i = i->next) { // for all draggables of this
1062         GrDraggable *da1 = (GrDraggable *) i->data;
1063         for (GSList const* j = other->draggables; j != NULL; j = j->next) { // for all draggables of other
1064             GrDraggable *da2 = (GrDraggable *) j->data;
1065             if (!da1->mayMerge(da2))
1066                 return false;
1067         }
1068     }
1069     return true;
1070 }
1071
1072 bool
1073 GrDragger::mayMerge (GrDraggable *da2)
1074 {
1075     for (GSList const* i = this->draggables; i != NULL; i = i->next) { // for all draggables of this
1076         GrDraggable *da1 = (GrDraggable *) i->data;
1077         if (!da1->mayMerge(da2))
1078             return false;
1079     }
1080     return true;
1081 }
1082
1083 /**
1084 Updates the statusbar tip of the dragger knot, based on its draggables
1085  */
1086 void
1087 GrDragger::updateTip ()
1088 {
1089         if (this->knot && this->knot->tip) {
1090                 g_free (this->knot->tip);
1091                 this->knot->tip = NULL;
1092         }
1093
1094     if (g_slist_length (this->draggables) == 1) {
1095         GrDraggable *draggable = (GrDraggable *) this->draggables->data;
1096         char *item_desc = sp_item_description(draggable->item);
1097         switch (draggable->point_type) {
1098             case POINT_LG_MID:
1099             case POINT_RG_MID1:
1100             case POINT_RG_MID2:
1101                 this->knot->tip = g_strdup_printf (_("%s %d for: %s%s; drag with <b>Ctrl</b> to snap offset; click with <b>Ctrl+Alt</b> to delete stop"),
1102                                                    _(gr_knot_descr[draggable->point_type]),
1103                                                    draggable->point_i,
1104                                                    item_desc,
1105                                                    draggable->fill_or_stroke == false ? _(" (stroke)") : "");
1106                 break;
1107
1108             default:
1109                 this->knot->tip = g_strdup_printf (_("%s for: %s%s; drag with <b>Ctrl</b> to snap angle, with <b>Ctrl+Alt</b> to preserve angle, with <b>Ctrl+Shift</b> to scale around center"),
1110                                                    _(gr_knot_descr[draggable->point_type]),
1111                                                    item_desc,
1112                                                    draggable->fill_or_stroke == false ? _(" (stroke)") : "");
1113                 break;
1114         }
1115         g_free(item_desc);
1116     } else if (g_slist_length (draggables) == 2 && isA (POINT_RG_CENTER) && isA (POINT_RG_FOCUS)) {
1117         this->knot->tip = g_strdup_printf (_("Radial gradient <b>center</b> and <b>focus</b>; drag with <b>Shift</b> to separate focus"));
1118     } else {
1119         int length = g_slist_length (this->draggables);
1120         this->knot->tip = g_strdup_printf (ngettext("Gradient point shared by <b>%d</b> gradient; drag with <b>Shift</b> to separate",
1121                                                     "Gradient point shared by <b>%d</b> gradients; drag with <b>Shift</b> to separate",
1122                                                     length),
1123                                            length);
1124     }
1125 }
1126
1127 /**
1128 Adds a draggable to the dragger
1129  */
1130 void
1131 GrDragger::updateKnotShape ()
1132 {
1133     if (!draggables)
1134         return;
1135     GrDraggable *last = (GrDraggable *) g_slist_last(draggables)->data;
1136     g_object_set (G_OBJECT (this->knot->item), "shape", gr_knot_shapes[last->point_type], NULL);
1137 }
1138
1139 /**
1140 Adds a draggable to the dragger
1141  */
1142 void
1143 GrDragger::addDraggable (GrDraggable *draggable)
1144 {
1145     this->draggables = g_slist_prepend (this->draggables, draggable);
1146
1147     this->updateTip();
1148 }
1149
1150
1151 /**
1152 Moves this dragger to the point of the given draggable, acting upon all other draggables
1153  */
1154 void
1155 GrDragger::moveThisToDraggable (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, bool write_repr)
1156 {
1157     this->point = sp_item_gradient_get_coords (item, point_type, point_i, fill_or_stroke);
1158     this->point_original = this->point;
1159
1160     sp_knot_moveto (this->knot, this->point);
1161
1162     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1163         GrDraggable *da = (GrDraggable *) i->data;
1164         if ( (da->item == item) &&
1165              (point_type == -1 || da->point_type == point_type) &&
1166              (point_i == -1 || da->point_i == point_i) &&
1167              (da->fill_or_stroke == fill_or_stroke) ) {
1168             continue;
1169         }
1170         sp_item_gradient_set_coords (da->item, da->point_type, da->point_i, this->point, da->fill_or_stroke, write_repr, false);
1171     }
1172     // FIXME: here we should also call this->updateDependencies(write_repr); to propagate updating, but how to prevent loops?
1173 }
1174
1175
1176 /**
1177 Moves all midstop draggables that depend on this one
1178  */
1179 void
1180 GrDragger::updateMidstopDependencies (GrDraggable *draggable, bool write_repr) {
1181     SPObject *server = draggable->getServer();
1182     if (!server)
1183         return;
1184     guint num = SP_GRADIENT(server)->vector.stops.size();
1185     if (num <= 2) return;
1186
1187     if ( SP_IS_LINEARGRADIENT(server) ) {
1188         for ( guint i = 1; i < num - 1; i++ ) {
1189             this->moveOtherToDraggable (draggable->item, POINT_LG_MID, i, draggable->fill_or_stroke, write_repr);
1190         }
1191     } else  if ( SP_IS_RADIALGRADIENT(server) ) {
1192         for ( guint i = 1; i < num - 1; i++ ) {
1193             this->moveOtherToDraggable (draggable->item, POINT_RG_MID1, i, draggable->fill_or_stroke, write_repr);
1194             this->moveOtherToDraggable (draggable->item, POINT_RG_MID2, i, draggable->fill_or_stroke, write_repr);
1195         }
1196     }
1197 }
1198
1199
1200 /**
1201 Moves all draggables that depend on this one
1202  */
1203 void
1204 GrDragger::updateDependencies (bool write_repr)
1205 {
1206     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1207         GrDraggable *draggable = (GrDraggable *) i->data;
1208         switch (draggable->point_type) {
1209             case POINT_LG_BEGIN:
1210                 {
1211                     // the end point is dependent only when dragging with ctrl+shift
1212                     this->moveOtherToDraggable (draggable->item, POINT_LG_END, -1, draggable->fill_or_stroke, write_repr);
1213
1214                     this->updateMidstopDependencies (draggable, write_repr);
1215                 }
1216                 break;
1217             case POINT_LG_END:
1218                 {
1219                     // the begin point is dependent only when dragging with ctrl+shift
1220                     this->moveOtherToDraggable (draggable->item, POINT_LG_BEGIN, 0, draggable->fill_or_stroke, write_repr);
1221
1222                     this->updateMidstopDependencies (draggable, write_repr);
1223                 }
1224                 break;
1225             case POINT_LG_MID:
1226                 // no other nodes depend on mid points.
1227                 break;
1228             case POINT_RG_R2:
1229                 this->moveOtherToDraggable (draggable->item, POINT_RG_R1, -1, draggable->fill_or_stroke, write_repr);
1230                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1231                 this->updateMidstopDependencies (draggable, write_repr);
1232                 break;
1233             case POINT_RG_R1:
1234                 this->moveOtherToDraggable (draggable->item, POINT_RG_R2, -1, draggable->fill_or_stroke, write_repr);
1235                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1236                 this->updateMidstopDependencies (draggable, write_repr);
1237                 break;
1238             case POINT_RG_CENTER:
1239                 this->moveOtherToDraggable (draggable->item, POINT_RG_R1, -1, draggable->fill_or_stroke, write_repr);
1240                 this->moveOtherToDraggable (draggable->item, POINT_RG_R2, -1, draggable->fill_or_stroke, write_repr);
1241                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1242                 this->updateMidstopDependencies (draggable, write_repr);
1243                 break;
1244             case POINT_RG_FOCUS:
1245                 // nothing can depend on that
1246                 break;
1247             case POINT_RG_MID1:
1248                 this->moveOtherToDraggable (draggable->item, POINT_RG_MID2, draggable->point_i, draggable->fill_or_stroke, write_repr);
1249                 break;
1250             case POINT_RG_MID2:
1251                 this->moveOtherToDraggable (draggable->item, POINT_RG_MID1, draggable->point_i, draggable->fill_or_stroke, write_repr);
1252                 break;
1253             default:
1254                 break;
1255         }
1256     }
1257 }
1258
1259
1260
1261 GrDragger::GrDragger (GrDrag *parent, Geom::Point p, GrDraggable *draggable)
1262   : point(p),
1263     point_original(p)
1264 {
1265     this->draggables = NULL;
1266
1267     this->parent = parent;
1268
1269     // create the knot
1270     this->knot = sp_knot_new (parent->desktop, NULL);
1271     this->knot->setMode(SP_KNOT_MODE_XOR);
1272     this->knot->setFill(GR_KNOT_COLOR_NORMAL, GR_KNOT_COLOR_MOUSEOVER, GR_KNOT_COLOR_MOUSEOVER);
1273     this->knot->setStroke(0x0000007f, 0x0000007f, 0x0000007f);
1274     sp_knot_update_ctrl(this->knot);
1275
1276     // move knot to the given point
1277     sp_knot_set_position (this->knot, p, SP_KNOT_STATE_NORMAL);
1278     sp_knot_show (this->knot);
1279
1280     // connect knot's signals
1281     if ( (draggable)  // it can be NULL if a node in unsnapped (eg. focus point unsnapped from center)
1282                        // luckily, midstops never snap to other nodes so are never unsnapped...
1283          && ( (draggable->point_type == POINT_LG_MID)
1284               || (draggable->point_type == POINT_RG_MID1)
1285               || (draggable->point_type == POINT_RG_MID2) ) )
1286     {
1287         this->handler_id = g_signal_connect (G_OBJECT (this->knot), "moved", G_CALLBACK (gr_knot_moved_midpoint_handler), this);
1288     } else {
1289         this->handler_id = g_signal_connect (G_OBJECT (this->knot), "moved", G_CALLBACK (gr_knot_moved_handler), this);
1290     }
1291     g_signal_connect (G_OBJECT (this->knot), "clicked", G_CALLBACK (gr_knot_clicked_handler), this);
1292     g_signal_connect (G_OBJECT (this->knot), "doubleclicked", G_CALLBACK (gr_knot_doubleclicked_handler), this);
1293     g_signal_connect (G_OBJECT (this->knot), "grabbed", G_CALLBACK (gr_knot_grabbed_handler), this);
1294     g_signal_connect (G_OBJECT (this->knot), "ungrabbed", G_CALLBACK (gr_knot_ungrabbed_handler), this);
1295
1296     // add the initial draggable
1297     if (draggable)
1298         this->addDraggable (draggable);
1299     updateKnotShape();
1300 }
1301
1302 GrDragger::~GrDragger ()
1303 {
1304     // unselect if it was selected
1305     this->parent->setDeselected(this);
1306
1307     // disconnect signals
1308     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_moved_handler), this);
1309     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_clicked_handler), this);
1310     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_doubleclicked_handler), this);
1311     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_grabbed_handler), this);
1312     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_ungrabbed_handler), this);
1313
1314     /* unref should call destroy */
1315     g_object_unref (G_OBJECT (this->knot));
1316
1317     // delete all draggables
1318     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1319         delete ((GrDraggable *) i->data);
1320     }
1321     g_slist_free (this->draggables);
1322     this->draggables = NULL;
1323 }
1324
1325 /**
1326 Select the dragger which has the given draggable.
1327 */
1328 GrDragger *
1329 GrDrag::getDraggerFor (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke)
1330 {
1331     for (GList const* i = this->draggers; i != NULL; i = i->next) {
1332         GrDragger *dragger = (GrDragger *) i->data;
1333         for (GSList const* j = dragger->draggables; j != NULL; j = j->next) {
1334             GrDraggable *da2 = (GrDraggable *) j->data;
1335             if ( (da2->item == item) &&
1336                  (point_type == -1 || da2->point_type == point_type) && // -1 means this does not matter
1337                  (point_i == -1 || da2->point_i == point_i) && // -1 means this does not matter
1338                  (da2->fill_or_stroke == fill_or_stroke)) {
1339                 return (dragger);
1340             }
1341         }
1342     }
1343     return NULL;
1344 }
1345
1346
1347 void
1348 GrDragger::moveOtherToDraggable (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, bool write_repr)
1349 {
1350     GrDragger *d = this->parent->getDraggerFor (item, point_type, point_i, fill_or_stroke);
1351     if (d && d !=  this) {
1352         d->moveThisToDraggable (item, point_type, point_i, fill_or_stroke, write_repr);
1353     }
1354 }
1355
1356
1357 /**
1358   Draw this dragger as selected
1359 */
1360 void
1361 GrDragger::select()
1362 {
1363     this->knot->fill [SP_KNOT_STATE_NORMAL] = GR_KNOT_COLOR_SELECTED;
1364     g_object_set (G_OBJECT (this->knot->item), "fill_color", GR_KNOT_COLOR_SELECTED, NULL);
1365 }
1366
1367 /**
1368   Draw this dragger as normal (deselected)
1369 */
1370 void
1371 GrDragger::deselect()
1372 {
1373     this->knot->fill [SP_KNOT_STATE_NORMAL] = GR_KNOT_COLOR_NORMAL;
1374     g_object_set (G_OBJECT (this->knot->item), "fill_color", GR_KNOT_COLOR_NORMAL, NULL);
1375 }
1376
1377 bool
1378 GrDragger::isSelected()
1379 {
1380     return g_list_find (parent->selected, this);
1381 }
1382
1383 /**
1384 \brief Deselect all stops/draggers (private)
1385 */
1386 void
1387 GrDrag::deselect_all()
1388 {
1389     while (selected) {
1390         ( (GrDragger*) selected->data)->deselect();
1391         selected = g_list_remove(selected, selected->data);
1392     }
1393 }
1394
1395 /**
1396 \brief Deselect all stops/draggers (public; emits signal)
1397 */
1398 void
1399 GrDrag::deselectAll()
1400 {
1401     deselect_all();
1402     this->desktop->emitToolSubselectionChanged(NULL);
1403 }
1404
1405 /**
1406 \brief Select all stops/draggers
1407 */
1408 void
1409 GrDrag::selectAll()
1410 {
1411     for (GList *l = this->draggers; l != NULL; l = l->next) {
1412         GrDragger *d = ((GrDragger *) l->data);
1413         setSelected (d, true, true);
1414     }
1415 }
1416
1417 /**
1418 \brief Select all stops/draggers that match the coords
1419 */
1420 void
1421 GrDrag::selectByCoords(std::vector<Geom::Point> coords)
1422 {
1423     for (GList *l = this->draggers; l != NULL; l = l->next) {
1424         GrDragger *d = ((GrDragger *) l->data);
1425         for (guint k = 0; k < coords.size(); k++) {
1426             if (Geom::L2 (d->point - coords[k]) < 1e-4) {
1427                 setSelected (d, true, true);
1428             }
1429         }
1430     }
1431 }
1432
1433
1434 /**
1435 \brief Select all stops/draggers that fall within the rect
1436 */
1437 void
1438 GrDrag::selectRect(Geom::Rect const &r)
1439 {
1440     for (GList *l = this->draggers; l != NULL; l = l->next) {
1441         GrDragger *d = ((GrDragger *) l->data);
1442         if (r.contains(d->point)) {
1443            setSelected (d, true, true);
1444         }
1445     }
1446 }
1447
1448 /**
1449 \brief Select a dragger
1450 \param dragger       The dragger to select
1451 \param add_to_selection   If true, add to selection, otherwise deselect others
1452 \param override      If true, always select this node, otherwise toggle selected status
1453 */
1454 void
1455 GrDrag::setSelected (GrDragger *dragger, bool add_to_selection, bool override)
1456 {
1457     GrDragger *seldragger = NULL;
1458
1459     if (add_to_selection) {
1460         if (!dragger) return;
1461         if (override) {
1462             if (!g_list_find(selected, dragger)) {
1463                 selected = g_list_prepend(selected, dragger);
1464             }
1465             dragger->select();
1466             seldragger = dragger;
1467         } else { // toggle
1468             if (g_list_find(selected, dragger)) {
1469                 selected = g_list_remove(selected, dragger);
1470                 dragger->deselect();
1471                 if (selected) {
1472                     seldragger = (GrDragger*) selected->data; // select the dragger that is first in the list
1473                 }
1474             } else {
1475                 selected = g_list_prepend(selected, dragger);
1476                 dragger->select();
1477                 seldragger = dragger;
1478             }
1479         }
1480     } else {
1481         deselect_all();
1482         if (dragger) {
1483             selected = g_list_prepend(selected, dragger);
1484             dragger->select();
1485             seldragger = dragger;
1486         }
1487     }
1488     if (seldragger) {
1489         this->desktop->emitToolSubselectionChanged((gpointer) seldragger);
1490     }
1491 }
1492
1493 /**
1494 \brief Deselect a dragger
1495 \param dragger       The dragger to deselect
1496 */
1497 void
1498 GrDrag::setDeselected (GrDragger *dragger)
1499 {
1500     if (g_list_find(selected, dragger)) {
1501         selected = g_list_remove(selected, dragger);
1502         dragger->deselect();
1503     }
1504     this->desktop->emitToolSubselectionChanged((gpointer) (selected ? selected->data : NULL ));
1505 }
1506
1507
1508
1509 /**
1510 Create a line from p1 to p2 and add it to the lines list
1511  */
1512 void
1513 GrDrag::addLine (SPItem *item, Geom::Point p1, Geom::Point p2, guint32 rgba)
1514 {
1515     SPCanvasItem *line = sp_canvas_item_new(sp_desktop_controls(this->desktop),
1516                                                             SP_TYPE_CTRLLINE, NULL);
1517     sp_canvas_item_move_to_z(line, 0);
1518     SP_CTRLLINE(line)->item = item;
1519     sp_ctrlline_set_coords(SP_CTRLLINE(line), p1, p2);
1520     if (rgba != GR_LINE_COLOR_FILL) // fill is the default, so don't set color for it to speed up redraw
1521         sp_ctrlline_set_rgba32 (SP_CTRLLINE(line), rgba);
1522     sp_canvas_item_show (line);
1523     this->lines = g_slist_append (this->lines, line);
1524 }
1525
1526 /**
1527 If there already exists a dragger within MERGE_DIST of p, add the draggable to it; otherwise create
1528 new dragger and add it to draggers list
1529  */
1530 void
1531 GrDrag::addDragger (GrDraggable *draggable)
1532 {
1533     Geom::Point p = sp_item_gradient_get_coords (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
1534
1535     for (GList *i = this->draggers; i != NULL; i = i->next) {
1536         GrDragger *dragger = (GrDragger *) i->data;
1537         if (dragger->mayMerge (draggable) && Geom::L2 (dragger->point - p) < MERGE_DIST) {
1538             // distance is small, merge this draggable into dragger, no need to create new dragger
1539             dragger->addDraggable (draggable);
1540             dragger->updateKnotShape();
1541             return;
1542         }
1543     }
1544
1545     GrDragger *new_dragger = new GrDragger(this, p, draggable);
1546     // fixme: draggers should be added AFTER the last one: this way tabbing through them will be from begin to end.
1547     this->draggers = g_list_append (this->draggers, new_dragger);
1548 }
1549
1550 /**
1551 Add draggers for the radial gradient rg on item
1552 */
1553 void
1554 GrDrag::addDraggersRadial (SPRadialGradient *rg, SPItem *item, bool fill_or_stroke)
1555 {
1556     addDragger (new GrDraggable (item, POINT_RG_CENTER, 0, fill_or_stroke));
1557     guint num = rg->vector.stops.size();
1558     if (num > 2) {
1559         for ( guint i = 1; i < num - 1; i++ ) {
1560             addDragger (new GrDraggable (item, POINT_RG_MID1, i, fill_or_stroke));
1561         }
1562     }
1563     addDragger (new GrDraggable (item, POINT_RG_R1, num-1, fill_or_stroke));
1564     if (num > 2) {
1565         for ( guint i = 1; i < num - 1; i++ ) {
1566             addDragger (new GrDraggable (item, POINT_RG_MID2, i, fill_or_stroke));
1567         }
1568     }
1569     addDragger (new GrDraggable (item, POINT_RG_R2, num-1, fill_or_stroke));
1570     addDragger (new GrDraggable (item, POINT_RG_FOCUS, 0, fill_or_stroke));
1571 }
1572
1573 /**
1574 Add draggers for the linear gradient lg on item
1575 */
1576 void
1577 GrDrag::addDraggersLinear (SPLinearGradient *lg, SPItem *item, bool fill_or_stroke)
1578 {
1579     addDragger (new GrDraggable (item, POINT_LG_BEGIN, 0, fill_or_stroke));
1580     guint num = lg->vector.stops.size();
1581     if (num > 2) {
1582         for ( guint i = 1; i < num - 1; i++ ) {
1583             addDragger (new GrDraggable (item, POINT_LG_MID, i, fill_or_stroke));
1584         }
1585     }
1586     addDragger (new GrDraggable (item, POINT_LG_END, num-1, fill_or_stroke));
1587 }
1588
1589 /**
1590 Artificially grab the knot of this dragger; used by the gradient context
1591 */
1592 void
1593 GrDrag::grabKnot (GrDragger *dragger, gint x, gint y, guint32 etime)
1594 {
1595     if (dragger) {
1596         sp_knot_start_dragging (dragger->knot, dragger->point, x, y, etime);
1597     }
1598 }
1599
1600 /**
1601 Artificially grab the knot of the dragger with this draggable; used by the gradient context
1602 */
1603 void
1604 GrDrag::grabKnot (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, gint x, gint y, guint32 etime)
1605 {
1606     GrDragger *dragger = getDraggerFor (item, point_type, point_i, fill_or_stroke);
1607     if (dragger) {
1608         sp_knot_start_dragging (dragger->knot, dragger->point, x, y, etime);
1609     }
1610 }
1611
1612 /**
1613 Regenerates the draggers list from the current selection; is called when selection is changed or
1614 modified, also when a radial dragger needs to update positions of other draggers in the gradient
1615 */
1616 void
1617 GrDrag::updateDraggers ()
1618 {
1619     while (selected) {
1620         selected = g_list_remove(selected, selected->data);
1621     }
1622     // delete old draggers
1623     for (GList const* i = this->draggers; i != NULL; i = i->next) {
1624         delete ((GrDragger *) i->data);
1625     }
1626     g_list_free (this->draggers);
1627     this->draggers = NULL;
1628
1629     g_return_if_fail (this->selection != NULL);
1630
1631     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1632
1633         SPItem *item = SP_ITEM(i->data);
1634         SPStyle *style = SP_OBJECT_STYLE (item);
1635
1636         if (style && (style->fill.isPaintserver())) {
1637             SPObject *server = SP_OBJECT_STYLE_FILL_SERVER (item);
1638             if (SP_IS_LINEARGRADIENT (server)) {
1639                 addDraggersLinear (SP_LINEARGRADIENT (server), item, true);
1640             } else if (SP_IS_RADIALGRADIENT (server)) {
1641                 addDraggersRadial (SP_RADIALGRADIENT (server), item, true);
1642             }
1643         }
1644
1645         if (style && (style->stroke.isPaintserver())) {
1646             SPObject *server = SP_OBJECT_STYLE_STROKE_SERVER (item);
1647             if (SP_IS_LINEARGRADIENT (server)) {
1648                 addDraggersLinear (SP_LINEARGRADIENT (server), item, false);
1649             } else if (SP_IS_RADIALGRADIENT (server)) {
1650                 addDraggersRadial (SP_RADIALGRADIENT (server), item, false);
1651             }
1652         }
1653     }
1654 }
1655
1656 /**
1657 Regenerates the lines list from the current selection; is called on each move of a dragger, so that
1658 lines are always in sync with the actual gradient
1659 */
1660 void
1661 GrDrag::updateLines ()
1662 {
1663     // delete old lines
1664     for (GSList const *i = this->lines; i != NULL; i = i->next) {
1665         gtk_object_destroy( GTK_OBJECT (i->data));
1666     }
1667     g_slist_free (this->lines);
1668     this->lines = NULL;
1669
1670     g_return_if_fail (this->selection != NULL);
1671
1672     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1673
1674         SPItem *item = SP_ITEM(i->data);
1675
1676         SPStyle *style = SP_OBJECT_STYLE (item);
1677
1678         if (style && (style->fill.isPaintserver())) {
1679             SPObject *server = SP_OBJECT_STYLE_FILL_SERVER (item);
1680             if (SP_IS_LINEARGRADIENT (server)) {
1681                 this->addLine (item, sp_item_gradient_get_coords (item, POINT_LG_BEGIN, 0, true), sp_item_gradient_get_coords (item, POINT_LG_END, 0, true), GR_LINE_COLOR_FILL);
1682             } else if (SP_IS_RADIALGRADIENT (server)) {
1683                 Geom::Point center = sp_item_gradient_get_coords (item, POINT_RG_CENTER, 0, true);
1684                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R1, 0, true), GR_LINE_COLOR_FILL);
1685                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R2, 0, true), GR_LINE_COLOR_FILL);
1686             }
1687         }
1688
1689         if (style && (style->stroke.isPaintserver())) {
1690             SPObject *server = SP_OBJECT_STYLE_STROKE_SERVER (item);
1691             if (SP_IS_LINEARGRADIENT (server)) {
1692                 this->addLine (item, sp_item_gradient_get_coords (item, POINT_LG_BEGIN, 0, false), sp_item_gradient_get_coords (item, POINT_LG_END, 0, false), GR_LINE_COLOR_STROKE);
1693             } else if (SP_IS_RADIALGRADIENT (server)) {
1694                 Geom::Point center = sp_item_gradient_get_coords (item, POINT_RG_CENTER, 0, false);
1695                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R1, 0, false), GR_LINE_COLOR_STROKE);
1696                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R2, 0, false), GR_LINE_COLOR_STROKE);
1697             }
1698         }
1699     }
1700 }
1701
1702 /**
1703 Regenerates the levels list from the current selection
1704 */
1705 void
1706 GrDrag::updateLevels ()
1707 {
1708     hor_levels.clear();
1709     vert_levels.clear();
1710
1711     g_return_if_fail (this->selection != NULL);
1712
1713     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1714         SPItem *item = SP_ITEM(i->data);
1715         Geom::OptRect rect = sp_item_bbox_desktop (item);
1716         if (rect) {
1717             // Remember the edges of the bbox and the center axis
1718             hor_levels.push_back(rect->min()[Geom::Y]);
1719             hor_levels.push_back(rect->max()[Geom::Y]);
1720             hor_levels.push_back(0.5 * (rect->min()[Geom::Y] + rect->max()[Geom::Y]));
1721             vert_levels.push_back(rect->min()[Geom::X]);
1722             vert_levels.push_back(rect->max()[Geom::X]);
1723             vert_levels.push_back(0.5 * (rect->min()[Geom::X] + rect->max()[Geom::X]));
1724         }
1725     }
1726 }
1727
1728 void
1729 GrDrag::selected_reverse_vector ()
1730 {
1731     if (selected == NULL)
1732         return;
1733
1734     for (GSList const* i = ( (GrDragger*) selected->data )->draggables; i != NULL; i = i->next) {
1735         GrDraggable *draggable = (GrDraggable *) i->data;
1736
1737         sp_item_gradient_reverse_vector (draggable->item, draggable->fill_or_stroke);
1738     }
1739 }
1740
1741 void
1742 GrDrag::selected_move_nowrite (double x, double y, bool scale_radial)
1743 {
1744     selected_move (x, y, false, scale_radial);
1745 }
1746
1747 void
1748 GrDrag::selected_move (double x, double y, bool write_repr, bool scale_radial)
1749 {
1750     if (selected == NULL)
1751         return;
1752
1753     bool did = false;
1754
1755     for (GList *i = selected; i != NULL; i = i->next) {
1756         GrDragger *d = (GrDragger *) i->data;
1757
1758         if (!d->isA(POINT_LG_MID) && !d->isA(POINT_RG_MID1) && !d->isA(POINT_RG_MID2)) {
1759             // if this is an endpoint,
1760
1761             // Moving an rg center moves its focus and radii as well.
1762             // therefore, if this is a focus or radius and if selection
1763             // contains the center as well, do not move this one
1764             if (d->isA(POINT_RG_R1) || d->isA(POINT_RG_R2) ||
1765                 (d->isA(POINT_RG_FOCUS) && !d->isA(POINT_RG_CENTER))) {
1766                 bool skip_radius_with_center = false;
1767                 for (GList *di = selected; di != NULL; di = di->next) {
1768                     GrDragger *d_new = (GrDragger *) di->data;
1769                     if (d_new->isA (((GrDraggable *) d->draggables->data)->item,
1770                                     POINT_RG_CENTER,
1771                                     0,
1772                                     ((GrDraggable *) d->draggables->data)->fill_or_stroke)) {
1773                         // FIXME: here we take into account only the first draggable!
1774                         skip_radius_with_center = true;
1775                     }
1776                 }
1777                 if (skip_radius_with_center)
1778                     continue;
1779             }
1780
1781             did = true;
1782             d->point += Geom::Point (x, y);
1783             d->point_original = d->point;
1784             sp_knot_moveto (d->knot, d->point);
1785
1786             d->fireDraggables (write_repr, scale_radial);
1787
1788             d->updateDependencies(write_repr);
1789         }
1790     }
1791
1792     if (write_repr && did) {
1793         // we did an undoable action
1794         sp_document_maybe_done (sp_desktop_document (desktop), "grmoveh", SP_VERB_CONTEXT_GRADIENT,
1795                                 _("Move gradient handle(s)"));
1796         return;
1797     }
1798
1799     if (!did) { // none of the end draggers are selected, so let's try to move the mids
1800
1801         GrDragger *dragger = (GrDragger *) selected->data;
1802         // a midpoint dragger can (logically) only contain one GrDraggable
1803         GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
1804
1805         Geom::Point begin(0,0), end(0,0);
1806         Geom::Point low_lim(0,0), high_lim(0,0);
1807
1808         SPObject *server = draggable->getServer();
1809         GSList *moving = NULL;
1810         gr_midpoint_limits(dragger, server, &begin, &end, &low_lim, &high_lim, &moving);
1811
1812         Geom::Point p(x, y);
1813         p = snap_vector_midpoint (dragger->point + p, low_lim, high_lim, 0);
1814         Geom::Point displacement = p - dragger->point;
1815
1816         for (GSList const* i = moving; i != NULL; i = i->next) {
1817             GrDragger *drg = (GrDragger*) i->data;
1818             SPKnot *drgknot = drg->knot;
1819             drg->point += displacement;
1820             sp_knot_moveto (drgknot, drg->point);
1821             drg->fireDraggables (true);
1822             drg->updateDependencies(true);
1823             did = true;
1824         }
1825
1826         g_slist_free(moving);
1827
1828         if (write_repr && did) {
1829             // we did an undoable action
1830             sp_document_maybe_done (sp_desktop_document (desktop), "grmovem", SP_VERB_CONTEXT_GRADIENT,
1831                                     _("Move gradient mid stop(s)"));
1832         }
1833     }
1834 }
1835
1836 void
1837 GrDrag::selected_move_screen (double x, double y)
1838 {
1839     gdouble zoom = desktop->current_zoom();
1840     gdouble zx = x / zoom;
1841     gdouble zy = y / zoom;
1842
1843     selected_move (zx, zy);
1844 }
1845
1846 /**
1847 Select the knot next to the last selected one and deselect all other selected.
1848 */
1849 GrDragger *
1850 GrDrag::select_next ()
1851 {
1852     GrDragger *d = NULL;
1853     if (selected == NULL || g_list_find(draggers, selected->data)->next == NULL) {
1854         if (draggers)
1855             d = (GrDragger *) draggers->data;
1856     } else {
1857         d = (GrDragger *) g_list_find(draggers, selected->data)->next->data;
1858     }
1859     if (d)
1860         setSelected (d);
1861     return d;
1862 }
1863
1864 /**
1865 Select the knot previous from the last selected one and deselect all other selected.
1866 */
1867 GrDragger *
1868 GrDrag::select_prev ()
1869 {
1870     GrDragger *d = NULL;
1871     if (selected == NULL || g_list_find(draggers, selected->data)->prev == NULL) {
1872         if (draggers)
1873             d = (GrDragger *) g_list_last (draggers)->data;
1874     } else {
1875         d = (GrDragger *) g_list_find(draggers, selected->data)->prev->data;
1876     }
1877     if (d)
1878         setSelected (d);
1879     return d;
1880 }
1881
1882
1883 // FIXME: i.m.o. an ugly function that I just made to work, but... aargh! (Johan)
1884 void
1885 GrDrag::deleteSelected (bool just_one)
1886 {
1887     if (!selected) return;
1888
1889     SPDocument *document = false;
1890
1891     struct StructStopInfo {
1892         SPStop * spstop;
1893         GrDraggable * draggable;
1894         SPGradient * gradient;
1895         SPGradient * vector;
1896     };
1897
1898     GSList *midstoplist = NULL;  // list of stops that must be deleted (will be deleted first)
1899     GSList *endstoplist = NULL;  // list of stops that must be deleted
1900     while (selected) {
1901         GrDragger *dragger = (GrDragger*) selected->data;
1902         for (GSList * drgble = dragger->draggables; drgble != NULL; drgble = drgble->next) {
1903             GrDraggable *draggable = (GrDraggable*) drgble->data;
1904             SPGradient *gradient = sp_item_gradient (draggable->item, draggable->fill_or_stroke);
1905             SPGradient *vector   = sp_gradient_get_forked_vector_if_necessary (gradient, false);
1906
1907             switch (draggable->point_type) {
1908                 case POINT_LG_MID:
1909                 case POINT_RG_MID1:
1910                 case POINT_RG_MID2:
1911                     {
1912                         SPStop *stop = sp_get_stop_i(vector, draggable->point_i);
1913                         // check if already present in list. (e.g. when both RG_MID1 and RG_MID2 were selected)
1914                         bool present = false;
1915                         for (GSList const * l = midstoplist; l != NULL; l = l->next) {
1916                             if ( (SPStop*)l->data == stop ) {
1917                                 present = true;
1918                                 break; // no need to search further.
1919                             }
1920                         }
1921                         if (!present)
1922                             midstoplist = g_slist_append(midstoplist, stop);
1923                     }
1924                     break;
1925                 case POINT_LG_BEGIN:
1926                 case POINT_LG_END:
1927                 case POINT_RG_CENTER:
1928                 case POINT_RG_R1:
1929                 case POINT_RG_R2:
1930                     {
1931                         SPStop *stop = NULL;
1932                         if ( (draggable->point_type == POINT_LG_BEGIN) || (draggable->point_type == POINT_RG_CENTER) ) {
1933                             stop = sp_first_stop(vector);
1934                         } else {
1935                             stop = sp_last_stop(vector);
1936                         }
1937                         if (stop) {
1938                             StructStopInfo *stopinfo = new StructStopInfo;
1939                             stopinfo->spstop = stop;
1940                             stopinfo->draggable = draggable;
1941                             stopinfo->gradient = gradient;
1942                             stopinfo->vector = vector;
1943                             // check if already present in list. (e.g. when both R1 and R2 were selected)
1944                             bool present = false;
1945                             for (GSList const * l = endstoplist; l != NULL; l = l->next) {
1946                                 if ( ((StructStopInfo*)l->data)->spstop == stopinfo->spstop ) {
1947                                     present = true;
1948                                     break; // no need to search further.
1949                                 }
1950                             }
1951                             if (!present)
1952                                 endstoplist = g_slist_append(endstoplist, stopinfo);
1953                         }
1954                     }
1955                     break;
1956                 default:
1957                     break;
1958             }
1959         }
1960         selected = g_list_remove(selected, dragger);
1961         if ( just_one ) break; // iterate once if just_one is set.
1962     }
1963     while (midstoplist) {
1964         SPStop *stop = (SPStop*) midstoplist->data;
1965         document = SP_OBJECT_DOCUMENT (stop);
1966         Inkscape::XML::Node * parent = SP_OBJECT_REPR(stop)->parent();
1967         parent->removeChild(SP_OBJECT_REPR(stop));
1968         midstoplist = g_slist_remove(midstoplist, stop);
1969     }
1970     while (endstoplist) {
1971         StructStopInfo *stopinfo  = (StructStopInfo*) endstoplist->data;
1972         document = SP_OBJECT_DOCUMENT (stopinfo->spstop);
1973
1974         // 2 is the minimum, cannot delete more than that without deleting the whole vector
1975         // cannot use vector->vector.stops.size() because the vector might be invalidated by deletion of a midstop
1976         // manually count the children, don't know if there already exists a function for this...
1977         int len = 0;
1978         for ( SPObject *child = sp_object_first_child(stopinfo->vector) ;
1979               child != NULL ;
1980               child = SP_OBJECT_NEXT(child) )
1981         {
1982             if ( SP_IS_STOP(child) )  len ++;
1983         }
1984         if (len > 2)
1985         {
1986             switch (stopinfo->draggable->point_type) {
1987                 case POINT_LG_BEGIN:
1988                     {
1989                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
1990
1991                         SPLinearGradient *lg = SP_LINEARGRADIENT(stopinfo->gradient);
1992                         Geom::Point oldbegin = Geom::Point (lg->x1.computed, lg->y1.computed);
1993                         Geom::Point end = Geom::Point (lg->x2.computed, lg->y2.computed);
1994                         SPStop *stop = sp_first_stop(stopinfo->vector);
1995                         gdouble offset = stop->offset;
1996                         Geom::Point newbegin = oldbegin + offset * (end - oldbegin);
1997                         lg->x1.computed = newbegin[Geom::X];
1998                         lg->y1.computed = newbegin[Geom::Y];
1999
2000                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(stopinfo->gradient);
2001                         sp_repr_set_svg_double(repr, "x1", lg->x1.computed);
2002                         sp_repr_set_svg_double(repr, "y1", lg->y1.computed);
2003                         stop->offset = 0;
2004                         sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", 0);
2005
2006                         // iterate through midstops to set new offset values such that they won't move on canvas.
2007                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2008                         stop = sp_next_stop(stop);
2009                         while ( stop != laststop ) {
2010                             stop->offset = (stop->offset - offset)/(1 - offset);
2011                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2012                             stop = sp_next_stop(stop);
2013                         }
2014                     }
2015                     break;
2016                 case POINT_LG_END:
2017                     {
2018                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2019
2020                         SPLinearGradient *lg = SP_LINEARGRADIENT(stopinfo->gradient);
2021                         Geom::Point begin = Geom::Point (lg->x1.computed, lg->y1.computed);
2022                         Geom::Point oldend = Geom::Point (lg->x2.computed, lg->y2.computed);
2023                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2024                         gdouble offset = laststop->offset;
2025                         Geom::Point newend = begin + offset * (oldend - begin);
2026                         lg->x2.computed = newend[Geom::X];
2027                         lg->y2.computed = newend[Geom::Y];
2028
2029                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(stopinfo->gradient);
2030                         sp_repr_set_svg_double(repr, "x2", lg->x2.computed);
2031                         sp_repr_set_svg_double(repr, "y2", lg->y2.computed);
2032                         laststop->offset = 1;
2033                         sp_repr_set_css_double (SP_OBJECT_REPR (laststop), "offset", 1);
2034
2035                         // iterate through midstops to set new offset values such that they won't move on canvas.
2036                         SPStop *stop = sp_first_stop(stopinfo->vector);
2037                         stop = sp_next_stop(stop);
2038                         while ( stop != laststop ) {
2039                             stop->offset = stop->offset / offset;
2040                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2041                             stop = sp_next_stop(stop);
2042                         }
2043                     }
2044                     break;
2045                 case POINT_RG_CENTER:
2046                     {
2047                         SPStop *newfirst = sp_next_stop (stopinfo->spstop);
2048                         if (newfirst) {
2049                             newfirst->offset = 0;
2050                             sp_repr_set_css_double (SP_OBJECT_REPR (newfirst), "offset", 0);
2051                         }
2052                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2053                     }
2054                     break;
2055                 case POINT_RG_R1:
2056                 case POINT_RG_R2:
2057                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2058
2059                         SPRadialGradient *rg = SP_RADIALGRADIENT(stopinfo->gradient);
2060                         double oldradius = rg->r.computed;
2061                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2062                         gdouble offset = laststop->offset;
2063                         double newradius = offset * oldradius;
2064                         rg->r.computed = newradius;
2065
2066                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(rg);
2067                         sp_repr_set_svg_double(repr, "r", rg->r.computed);
2068                         laststop->offset = 1;
2069                         sp_repr_set_css_double (SP_OBJECT_REPR (laststop), "offset", 1);
2070
2071                         // iterate through midstops to set new offset values such that they won't move on canvas.
2072                         SPStop *stop = sp_first_stop(stopinfo->vector);
2073                         stop = sp_next_stop(stop);
2074                         while ( stop != laststop ) {
2075                             stop->offset = stop->offset / offset;
2076                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2077                             stop = sp_next_stop(stop);
2078                         }
2079                         break;
2080             }
2081         }
2082         else
2083         { // delete the gradient from the object. set fill to unset  FIXME: set to fill of unselected node?
2084             SPCSSAttr *css = sp_repr_css_attr_new ();
2085
2086             // stopinfo->spstop is the selected stop
2087             Inkscape::XML::Node *unselectedrepr = SP_OBJECT_REPR(stopinfo->vector)->firstChild();
2088             if (unselectedrepr == SP_OBJECT_REPR(stopinfo->spstop) ) {
2089                 unselectedrepr = unselectedrepr->next();
2090             }
2091
2092             if (unselectedrepr == NULL) {
2093                 if (stopinfo->draggable->fill_or_stroke) {
2094                     sp_repr_css_unset_property (css, "fill");
2095                 } else {
2096                     sp_repr_css_unset_property (css, "stroke");
2097                 }
2098             } else {
2099                 SPCSSAttr *stopcss = sp_repr_css_attr(unselectedrepr, "style");
2100                 if (stopinfo->draggable->fill_or_stroke) {
2101                     sp_repr_css_set_property(css, "fill", sp_repr_css_property(stopcss, "stop-color", "inkscape:unset"));
2102                     sp_repr_css_set_property(css, "fill-opacity", sp_repr_css_property(stopcss, "stop-opacity", "1"));
2103                 } else {
2104                     sp_repr_css_set_property(css, "stroke", sp_repr_css_property(stopcss, "stop-color", "inkscape:unset"));
2105                     sp_repr_css_set_property(css, "stroke-opacity", sp_repr_css_property(stopcss, "stop-opacity", "1"));
2106                 }
2107                 sp_repr_css_attr_unref (stopcss);
2108             }
2109
2110             sp_repr_css_change (SP_OBJECT_REPR (stopinfo->draggable->item), css, "style");
2111             sp_repr_css_attr_unref (css);
2112         }
2113
2114         endstoplist = g_slist_remove(endstoplist, stopinfo);
2115         delete stopinfo;
2116     }
2117
2118     if (document) {
2119         sp_document_done ( document, SP_VERB_CONTEXT_GRADIENT, _("Delete gradient stop(s)") );
2120     }
2121 }
2122
2123
2124 /*
2125   Local Variables:
2126   mode:c++
2127   c-file-style:"stroustrup"
2128   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
2129   indent-tabs-mode:nil
2130   fill-column:99
2131   End:
2132 */
2133 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :