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
  22 #include "desktop-handles.h"
  23 #include "selection.h"
  24 #include "desktop.h"
  25 #include "desktop-style.h"
  26 #include "document.h"
  27 #include "display/sp-ctrlline.h"
  28 #include "xml/repr.h"
  29 #include "svg/css-ostringstream.h"
  30 #include "svg/svg.h"
  31 #include "libnr/nr-point-fns.h"
  32 #include "prefs-utils.h"
  33 #include "sp-item.h"
  34 #include "style.h"
  35 #include "knot.h"
  36 #include "sp-linear-gradient.h"
  37 #include "sp-radial-gradient.h"
  38 #include "gradient-chemistry.h"
  39 #include "gradient-drag.h"
  40 #include "sp-stop.h"
  41 #include "snap.h"
  42 #include "sp-namedview.h"
  43 #include "selection-chemistry.h"
  44
  45
  46 #define GR_KNOT_COLOR_NORMAL 0xffffff00
  47 #define GR_KNOT_COLOR_MOUSEOVER 0xff000000
  48 #define GR_KNOT_COLOR_SELECTED 0x0000ff00
  49
  50 #define GR_LINE_COLOR_FILL 0x0000ff7f
  51 #define GR_LINE_COLOR_STROKE 0x9999007f
  52
  53 // screen pixels between knots when they snap:
  54 #define SNAP_DIST 5
  55
  56 // absolute distance between gradient points for them to become a single dragger when the drag is created:
  57 #define MERGE_DIST 0.1
  58
  59 // knot shapes corresponding to GrPointType enum
  60 SPKnotShapeType gr_knot_shapes [] = {
  61         SP_KNOT_SHAPE_SQUARE, //POINT_LG_BEGIN
  62         SP_KNOT_SHAPE_CIRCLE,  //POINT_LG_END
  63         SP_KNOT_SHAPE_DIAMOND, //POINT_LG_MID
  64         SP_KNOT_SHAPE_SQUARE,  // POINT_RG_CENTER
  65         SP_KNOT_SHAPE_CIRCLE,  // POINT_RG_R1
  66         SP_KNOT_SHAPE_CIRCLE,  // POINT_RG_R2
  67         SP_KNOT_SHAPE_CROSS, // POINT_RG_FOCUS
  68         SP_KNOT_SHAPE_DIAMOND, //POINT_RG_MID1
  69         SP_KNOT_SHAPE_DIAMOND //POINT_RG_MID2
  70 };
  71
  72 const gchar *gr_knot_descr [] = {
  73     N_("Linear gradient <b>start</b>"), //POINT_LG_BEGIN
  74     N_("Linear gradient <b>end</b>"),
  75     N_("Linear gradient <b>mid stop</b>"),
  76     N_("Radial gradient <b>center</b>"),
  77     N_("Radial gradient <b>radius</b>"),
  78     N_("Radial gradient <b>radius</b>"),
  79     N_("Radial gradient <b>focus</b>"), // POINT_RG_FOCUS
  80     N_("Radial gradient <b>mid stop</b>"),
  81     N_("Radial gradient <b>mid stop</b>")
  82 };
  83
  84 static void
  85 gr_drag_sel_changed(Inkscape::Selection *selection, gpointer data)
  86 {
  87         GrDrag *drag = (GrDrag *) data;
  88         drag->updateDraggers ();
  89         drag->updateLines ();
  90         drag->updateLevels ();
  91 }
  92
  93 static void
  94 gr_drag_sel_modified (Inkscape::Selection *selection, guint flags, gpointer data)
  95 {
  96     GrDrag *drag = (GrDrag *) data;
  97     if (drag->local_change) {
  98         drag->local_change = false;
  99     } else {
 100         drag->updateDraggers ();
 101     }
 102     drag->updateLines ();
 103     drag->updateLevels ();
 104 }
 105
 106 /**
 107 When a _query_style_signal is received, check that \a property requests fill/stroke/opacity (otherwise
 108 skip), and fill the \a style with the averaged color of all draggables of the selected dragger, if
 109 any.
 110 */
 111 int
 112 gr_drag_style_query (SPStyle *style, int property, gpointer data)
 113 {
 114     GrDrag *drag = (GrDrag *) data;
 115
 116     if (property != QUERY_STYLE_PROPERTY_FILL && property != QUERY_STYLE_PROPERTY_STROKE && property != QUERY_STYLE_PROPERTY_MASTEROPACITY) {
 117         return QUERY_STYLE_NOTHING;
 118     }
 119
 120     if (!drag->selected) {
 121         return QUERY_STYLE_NOTHING;
 122     } else {
 123         int ret = QUERY_STYLE_NOTHING;
 124
 125         float cf[4];
 126         cf[0] = cf[1] = cf[2] = cf[3] = 0;
 127
 128         int count = 0;
 129
 130         for (GList *i = drag->selected; i != NULL; i = i->next) { // for all selected draggers
 131             GrDragger *d = (GrDragger *) i->data;
 132             for (GSList const* j = d->draggables; j != NULL; j = j->next) { // for all draggables of dragger
 133                 GrDraggable *draggable = (GrDraggable *) j->data;
 134
 135                 if (ret == QUERY_STYLE_NOTHING) {
 136                     ret = QUERY_STYLE_SINGLE;
 137                 } else if (ret == QUERY_STYLE_SINGLE) {
 138                     ret = QUERY_STYLE_MULTIPLE_AVERAGED;
 139                 }
 140
 141                 guint32 c = sp_item_gradient_stop_query_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 142                 cf[0] += SP_RGBA32_R_F (c);
 143                 cf[1] += SP_RGBA32_G_F (c);
 144                 cf[2] += SP_RGBA32_B_F (c);
 145                 cf[3] += SP_RGBA32_A_F (c);
 146
 147                 count ++;
 148             }
 149         }
 150
 151         if (count) {
 152             cf[0] /= count;
 153             cf[1] /= count;
 154             cf[2] /= count;
 155             cf[3] /= count;
 156
 157             // set both fill and stroke with our stop-color and stop-opacity
 158             style->fill.clear();
 159             style->fill.setColor( cf[0], cf[1], cf[2] );
 160             style->fill.set = TRUE;
 161             style->stroke.clear();
 162             style->stroke.setColor( cf[0], cf[1], cf[2] );
 163             style->stroke.set = TRUE;
 164
 165             style->fill_opacity.value = SP_SCALE24_FROM_FLOAT (1.0);
 166             style->fill_opacity.set = TRUE;
 167             style->stroke_opacity.value = SP_SCALE24_FROM_FLOAT (1.0);
 168             style->stroke_opacity.set = TRUE;
 169
 170             style->opacity.value = SP_SCALE24_FROM_FLOAT (cf[3]);
 171             style->opacity.set = TRUE;
 172         }
 173
 174         return ret;
 175     }
 176 }
 177
 178 bool
 179 gr_drag_style_set (const SPCSSAttr *css, gpointer data)
 180 {
 181     GrDrag *drag = (GrDrag *) data;
 182
 183     if (!drag->selected)
 184         return false;
 185
 186     SPCSSAttr *stop = sp_repr_css_attr_new ();
 187
 188     // See if the css contains interesting properties, and if so, translate them into the format
 189     // acceptable for gradient stops
 190
 191     // any of color properties, in order of increasing priority:
 192     if (css->attribute("flood-color"))
 193         sp_repr_css_set_property (stop, "stop-color", css->attribute("flood-color"));
 194
 195     if (css->attribute("lighting-color"))
 196         sp_repr_css_set_property (stop, "stop-color", css->attribute("lighting-color"));
 197
 198     if (css->attribute("color"))
 199         sp_repr_css_set_property (stop, "stop-color", css->attribute("color"));
 200
 201     if (css->attribute("stroke") && strcmp(css->attribute("stroke"), "none"))
 202         sp_repr_css_set_property (stop, "stop-color", css->attribute("stroke"));
 203
 204     if (css->attribute("fill") && strcmp(css->attribute("fill"), "none"))
 205         sp_repr_css_set_property (stop, "stop-color", css->attribute("fill"));
 206
 207     if (css->attribute("stop-color"))
 208         sp_repr_css_set_property (stop, "stop-color", css->attribute("stop-color"));
 209
 210
 211     if (css->attribute("stop-opacity")) { // direct setting of stop-opacity has priority
 212         sp_repr_css_set_property (stop, "stop-opacity", css->attribute("stop-opacity"));
 213     } else {  // multiply all opacity properties:
 214         gdouble accumulated = 1.0;
 215         accumulated *= sp_svg_read_percentage(css->attribute("flood-opacity"), 1.0);
 216         accumulated *= sp_svg_read_percentage(css->attribute("opacity"), 1.0);
 217         accumulated *= sp_svg_read_percentage(css->attribute("stroke-opacity"), 1.0);
 218         accumulated *= sp_svg_read_percentage(css->attribute("fill-opacity"), 1.0);
 219
 220         Inkscape::CSSOStringStream os;
 221         os << accumulated;
 222         sp_repr_css_set_property (stop, "stop-opacity", os.str().c_str());
 223
 224         if ((css->attribute("fill") && !css->attribute("stroke") && !strcmp(css->attribute("fill"), "none")) ||
 225             (css->attribute("stroke") && !css->attribute("fill") && !strcmp(css->attribute("stroke"), "none")))
 226             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
 227     }
 228
 229     if (!stop->attributeList()) { // nothing for us here, pass it on
 230         sp_repr_css_attr_unref(stop);
 231         return false;
 232     }
 233
 234     for (GList const* sel = drag->selected; sel != NULL; sel = sel->next) { // for all selected draggers
 235         GrDragger* dragger = (GrDragger*) sel->data;
 236         for (GSList const* i = dragger->draggables; i != NULL; i = i->next) { // for all draggables of dragger
 237                GrDraggable *draggable = (GrDraggable *) i->data;
 238
 239                drag->local_change = true;
 240                sp_item_gradient_stop_set_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke, stop);
 241         }
 242     }
 243
 244     //sp_repr_css_print(stop);
 245     sp_repr_css_attr_unref(stop);
 246     return true;
 247 }
 248
 249 bool
 250 GrDrag::copy()
 251 {
 252     if (!selected)
 253         return false;
 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     guint32 const c32 = SP_RGBA32_F_COMPOSE(cf[0], cf[1], cf[2], cf[3]);
 283     gchar c[64];
 284
 285     SPCSSAttr *css = sp_repr_css_attr_new ();
 286     g_snprintf(c, 64, "#%06x", c32 >> 8);
 287     sp_repr_css_set_property (css, "fill", c);
 288     Inkscape::CSSOStringStream os;
 289     os << cf[3];
 290     sp_repr_css_set_property (css, "opacity", os.str().c_str());
 291     sp_set_style_clipboard (css);
 292
 293     g_snprintf(c, 64, "%06x%02x", c32 >> 8, c32 & 0x000000ff);
 294     Glib::ustring text;
 295     text += c;
 296     if (!text.empty())
 297     {
 298         Glib::RefPtr<Gtk::Clipboard> refClipboard =
 299             Gtk::Clipboard::get();
 300         refClipboard->set_text(text);
 301     }
 302
 303     return true;
 304 }
 305
 306 SPStop *
 307 GrDrag::addStopNearPoint (SPItem *item, NR::Point mouse_p, double tolerance)
 308 {
 309     gfloat offset; // type of SPStop.offset = gfloat
 310     SPGradient *gradient;
 311     bool fill_or_stroke = true;
 312     bool r1_knot = false;
 313
 314     bool addknot = false;
 315     do {
 316         gradient = sp_item_gradient (item, fill_or_stroke);
 317         if (SP_IS_LINEARGRADIENT(gradient)) {
 318             NR::Point begin   = sp_item_gradient_get_coords(item, POINT_LG_BEGIN, 0, fill_or_stroke);
 319             NR::Point end     = sp_item_gradient_get_coords(item, POINT_LG_END, 0, fill_or_stroke);
 320
 321             NR::Point nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 322             double dist_screen = NR::L2 (mouse_p - nearest);
 323             if ( dist_screen < tolerance ) {
 324                 // add the knot
 325                 offset = get_offset_between_points(nearest, begin, end);
 326                 addknot = true;
 327                 break; // break out of the while loop: add only one knot
 328             }
 329         } else if (SP_IS_RADIALGRADIENT(gradient)) {
 330             NR::Point begin = sp_item_gradient_get_coords(item, POINT_RG_CENTER, 0, fill_or_stroke);
 331             NR::Point end   = sp_item_gradient_get_coords(item, POINT_RG_R1, 0, fill_or_stroke);
 332             NR::Point nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 333             double dist_screen = NR::L2 (mouse_p - nearest);
 334             if ( dist_screen < tolerance ) {
 335                 offset = get_offset_between_points(nearest, begin, end);
 336                 addknot = true;
 337                 r1_knot = true;
 338                 break; // break out of the while loop: add only one knot
 339             }
 340
 341             end    = sp_item_gradient_get_coords(item, POINT_RG_R2, 0, fill_or_stroke);
 342             nearest = snap_vector_midpoint (mouse_p, begin, end, 0);
 343             dist_screen = NR::L2 (mouse_p - nearest);
 344             if ( dist_screen < tolerance ) {
 345                 offset = get_offset_between_points(nearest, begin, end);
 346                 addknot = true;
 347                 r1_knot = false;
 348                 break; // break out of the while loop: add only one knot
 349             }
 350         }
 351         fill_or_stroke = !fill_or_stroke;
 352     } while (!fill_or_stroke && !addknot) ;
 353
 354     if (addknot) {
 355         SPGradient *vector = sp_gradient_get_forked_vector_if_necessary (gradient, false);
 356         SPStop* prev_stop = sp_first_stop(vector);
 357         SPStop* next_stop = sp_next_stop(prev_stop);
 358         guint i = 1;
 359         while ( (next_stop) && (next_stop->offset < offset) ) {
 360             prev_stop = next_stop;
 361             next_stop = sp_next_stop(next_stop);
 362             i++;
 363         }
 364         if (!next_stop) {
 365             // logical error: the endstop should have offset 1 and should always be more than this offset here
 366             return NULL;
 367         }
 368
 369
 370         SPStop *newstop = sp_vector_add_stop (vector, prev_stop, next_stop, offset);
 371         sp_gradient_ensure_vector (gradient);
 372         updateDraggers();
 373
 374         return newstop;
 375     }
 376
 377     return NULL;
 378 }
 379
 380
 381 bool
 382 GrDrag::dropColor(SPItem *item, gchar *c, NR::Point p)
 383 {
 384     // first, see if we can drop onto one of the existing draggers
 385     for (GList *i = draggers; i != NULL; i = i->next) { // for all draggables of dragger
 386         GrDragger *d = (GrDragger *) i->data;
 387
 388         if (NR::L2(p - d->point)*desktop->current_zoom() < 5) {
 389            SPCSSAttr *stop = sp_repr_css_attr_new ();
 390            sp_repr_css_set_property (stop, "stop-color", c);
 391            sp_repr_css_set_property (stop, "stop-opacity", "1");
 392            for (GSList *j = d->draggables; j != NULL; j = j->next) { // for all draggables of dragger
 393                GrDraggable *draggable = (GrDraggable *) j->data;
 394                local_change = true;
 395                sp_item_gradient_stop_set_style (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke, stop);
 396            }
 397            sp_repr_css_attr_unref(stop);
 398            return true;
 399         }
 400     }
 401
 402     // now see if we're over line and create a new stop
 403     bool over_line = false;
 404     SPCtrlLine *line = NULL;
 405     if (lines) {
 406         for (GSList *l = lines; (l != NULL) && (!over_line); l = l->next) {
 407             line = (SPCtrlLine*) l->data;
 408             NR::Point nearest = snap_vector_midpoint (p, line->s, line->e, 0);
 409             double dist_screen = NR::L2 (p - nearest) * desktop->current_zoom();
 410             if (line->item && dist_screen < 5) {
 411                 SPStop *stop = addStopNearPoint (line->item, p, 5/desktop->current_zoom());
 412                 if (stop) {
 413                     SPCSSAttr *css = sp_repr_css_attr_new ();
 414                     sp_repr_css_set_property (css, "stop-color", c);
 415                     sp_repr_css_set_property (css, "stop-opacity", "1");
 416                     sp_repr_css_change (SP_OBJECT_REPR (stop), css, "style");
 417                     return true;
 418                 }
 419             }
 420         }
 421     }
 422
 423     return false;
 424 }
 425
 426
 427 GrDrag::GrDrag(SPDesktop *desktop) {
 428
 429     this->desktop = desktop;
 430
 431     this->selection = sp_desktop_selection(desktop);
 432
 433     this->draggers = NULL;
 434     this->lines = NULL;
 435     this->selected = NULL;
 436
 437     this->hor_levels.clear();
 438     this->vert_levels.clear();
 439
 440     this->local_change = false;
 441
 442     this->sel_changed_connection = this->selection->connectChanged(
 443         sigc::bind (
 444             sigc::ptr_fun(&gr_drag_sel_changed),
 445             (gpointer)this )
 446
 447         );
 448     this->sel_modified_connection = this->selection->connectModified(
 449         sigc::bind(
 450             sigc::ptr_fun(&gr_drag_sel_modified),
 451             (gpointer)this )
 452         );
 453
 454     this->style_set_connection = this->desktop->connectSetStyle(
 455         sigc::bind(
 456             sigc::ptr_fun(&gr_drag_style_set),
 457             (gpointer)this )
 458         );
 459
 460     this->style_query_connection = this->desktop->connectQueryStyle(
 461         sigc::bind(
 462             sigc::ptr_fun(&gr_drag_style_query),
 463             (gpointer)this )
 464         );
 465
 466     this->updateDraggers ();
 467     this->updateLines ();
 468     this->updateLevels ();
 469
 470     if (desktop->gr_item) {
 471         this->setSelected (getDraggerFor (desktop->gr_item, desktop->gr_point_type, desktop->gr_point_i, desktop->gr_fill_or_stroke));
 472     }
 473 }
 474
 475 GrDrag::~GrDrag()
 476 {
 477     this->sel_changed_connection.disconnect();
 478     this->sel_modified_connection.disconnect();
 479     this->style_set_connection.disconnect();
 480     this->style_query_connection.disconnect();
 481
 482     if (this->selected) {
 483         GrDraggable *draggable = (GrDraggable *)   ((GrDragger*)this->selected->data)->draggables->data;
 484         desktop->gr_item = draggable->item;
 485         desktop->gr_point_type = draggable->point_type;
 486         desktop->gr_point_i = draggable->point_i;
 487         desktop->gr_fill_or_stroke = draggable->fill_or_stroke;
 488     } else {
 489         desktop->gr_item = NULL;
 490         desktop->gr_point_type = 0;
 491         desktop->gr_point_i = 0;
 492         desktop->gr_fill_or_stroke = true;
 493     }
 494
 495     deselect_all();
 496     for (GList *l = this->draggers; l != NULL; l = l->next) {
 497         delete ((GrDragger *) l->data);
 498     }
 499     g_list_free (this->draggers);
 500     this->draggers = NULL;
 501     this->selected = NULL;
 502
 503     for (GSList *l = this->lines; l != NULL; l = l->next) {
 504         gtk_object_destroy( GTK_OBJECT (l->data));
 505     }
 506     g_slist_free (this->lines);
 507     this->lines = NULL;
 508 }
 509
 510 GrDraggable::GrDraggable (SPItem *item, guint point_type, guint point_i, bool fill_or_stroke)
 511 {
 512     this->item = item;
 513     this->point_type = point_type;
 514     this->point_i = point_i;
 515     this->fill_or_stroke = fill_or_stroke;
 516
 517     g_object_ref (G_OBJECT (this->item));
 518 }
 519
 520 GrDraggable::~GrDraggable ()
 521 {
 522     g_object_unref (G_OBJECT (this->item));
 523 }
 524
 525
 526 SPObject *
 527 GrDraggable::getServer ()
 528 {
 529     if (!item)
 530         return NULL;
 531
 532     SPObject *server = NULL;
 533     if (fill_or_stroke)
 534         server = SP_OBJECT_STYLE_FILL_SERVER (item);
 535     else
 536         server = SP_OBJECT_STYLE_STROKE_SERVER (item);
 537
 538     return server;
 539 }
 540
 541 static void
 542 gr_knot_moved_handler(SPKnot *knot, NR::Point const *ppointer, guint state, gpointer data)
 543 {
 544     GrDragger *dragger = (GrDragger *) data;
 545     GrDrag *drag = dragger->parent;
 546
 547     NR::Point p = *ppointer;
 548
 549     // FIXME: take from prefs
 550     double snap_dist = SNAP_DIST / dragger->parent->desktop->current_zoom();
 551
 552     if (state & GDK_SHIFT_MASK) {
 553         // with Shift; unsnap if we carry more than one draggable
 554         if (dragger->draggables && dragger->draggables->next) {
 555             // create a new dragger
 556             GrDragger *dr_new = new GrDragger (dragger->parent, dragger->point, NULL);
 557             dragger->parent->draggers = g_list_prepend (dragger->parent->draggers, dr_new);
 558             // relink to it all but the first draggable in the list
 559             for (GSList const* i = dragger->draggables->next; i != NULL; i = i->next) {
 560                 GrDraggable *draggable = (GrDraggable *) i->data;
 561                 dr_new->addDraggable (draggable);
 562             }
 563             dr_new->updateKnotShape();
 564             g_slist_free (dragger->draggables->next);
 565             dragger->draggables->next = NULL;
 566             dragger->updateKnotShape();
 567             dragger->updateTip();
 568         }
 569     } else if (!(state & GDK_CONTROL_MASK)) {
 570         // without Shift or Ctrl; see if we need to snap to another dragger
 571         for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 572             GrDragger *d_new = (GrDragger *) di->data;
 573             if (dragger->mayMerge(d_new) && NR::L2 (d_new->point - p) < snap_dist) {
 574
 575                 // Merge draggers:
 576                 for (GSList const* i = dragger->draggables; i != NULL; i = i->next) { // for all draggables of dragger
 577                     GrDraggable *draggable = (GrDraggable *) i->data;
 578                     // copy draggable to d_new:
 579                     GrDraggable *da_new = new GrDraggable (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 580                     d_new->addDraggable (da_new);
 581                 }
 582
 583                 // unlink and delete this dragger
 584                 dragger->parent->draggers = g_list_remove (dragger->parent->draggers, dragger);
 585                 delete dragger;
 586
 587                 // update the new merged dragger
 588                 d_new->fireDraggables(true, false, true);
 589                 d_new->parent->updateLines();
 590                 d_new->parent->setSelected (d_new);
 591                 d_new->updateKnotShape ();
 592                 d_new->updateTip ();
 593                 d_new->updateDependencies(true);
 594                 sp_document_done (sp_desktop_document (d_new->parent->desktop), SP_VERB_CONTEXT_GRADIENT,
 595                                   _("Merge gradient handles"));
 596                 return;
 597             }
 598         }
 599     }
 600
 601     if (!((state & GDK_SHIFT_MASK) || ((state & GDK_CONTROL_MASK) && (state & GDK_MOD1_MASK)))) {
 602         // Try snapping to the grid or guides
 603         SnapManager const &m = dragger->parent->desktop->namedview->snap_manager;
 604         Inkscape::SnappedPoint s = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, p, NULL);
 605         if (s.getDistance() < 1e6) {
 606             p = s.getPoint();
 607             sp_knot_moveto (knot, &p);
 608         } else {
 609             // No snapping so far, let's see if we need to snap to any of the levels
 610             for (guint i = 0; i < dragger->parent->hor_levels.size(); i++) {
 611                 if (fabs(p[NR::Y] - dragger->parent->hor_levels[i]) < snap_dist) {
 612                     p[NR::Y] = dragger->parent->hor_levels[i];
 613                     sp_knot_moveto (knot, &p);
 614                 }
 615             }
 616             for (guint i = 0; i < dragger->parent->vert_levels.size(); i++) {
 617                 if (fabs(p[NR::X] - dragger->parent->vert_levels[i]) < snap_dist) {
 618                     p[NR::X] = dragger->parent->vert_levels[i];
 619                     sp_knot_moveto (knot, &p);
 620                 }
 621             }
 622         }
 623     }
 624
 625     if (state & GDK_CONTROL_MASK) {
 626         unsigned snaps = abs(prefs_get_int_attribute("options.rotationsnapsperpi", "value", 12));
 627         /* 0 means no snapping. */
 628
 629         // This list will store snap vectors from all draggables of dragger
 630         GSList *snap_vectors = NULL;
 631
 632         for (GSList const* i = dragger->draggables; i != NULL; i = i->next) {
 633             GrDraggable *draggable = (GrDraggable *) i->data;
 634
 635             NR::Point *dr_snap = NULL;
 636
 637             if (draggable->point_type == POINT_LG_BEGIN || draggable->point_type == POINT_LG_END) {
 638                 for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 639                     GrDragger *d_new = (GrDragger *) di->data;
 640                     if (d_new == dragger)
 641                         continue;
 642                     if (d_new->isA (draggable->item,
 643                                     draggable->point_type == POINT_LG_BEGIN? POINT_LG_END : POINT_LG_BEGIN,
 644                                     draggable->fill_or_stroke)) {
 645                         // found the other end of the linear gradient;
 646                         if (state & GDK_SHIFT_MASK) {
 647                             // moving linear around center
 648                             NR::Point center = NR::Point (0.5*(d_new->point + dragger->point));
 649                             dr_snap = &center;
 650                         } else {
 651                             // moving linear around the other end
 652                             dr_snap = &d_new->point;
 653                         }
 654                     }
 655                 }
 656             } else if (draggable->point_type == POINT_RG_R1 || draggable->point_type == POINT_RG_R2 || draggable->point_type == POINT_RG_FOCUS) {
 657                 for (GList *di = dragger->parent->draggers; di != NULL; di = di->next) {
 658                     GrDragger *d_new = (GrDragger *) di->data;
 659                     if (d_new == dragger)
 660                         continue;
 661                     if (d_new->isA (draggable->item,
 662                                     POINT_RG_CENTER,
 663                                     draggable->fill_or_stroke)) {
 664                         // found the center of the radial gradient;
 665                         dr_snap = &(d_new->point);
 666                     }
 667                 }
 668             } else if (draggable->point_type == POINT_RG_CENTER) {
 669                 // radial center snaps to hor/vert relative to its original position
 670                 dr_snap = &(dragger->point_original);
 671             }
 672
 673             NR::Point *snap_vector = NULL;
 674             if (dr_snap) {
 675                 if (state & GDK_MOD1_MASK) {
 676                     // with Alt, snap to the original angle and its perpendiculars
 677                     snap_vector = get_snap_vector (p, *dr_snap, M_PI/2, NR::atan2 (dragger->point_original - *dr_snap));
 678                 } else {
 679                     // with Ctrl, snap to M_PI/snaps
 680                     snap_vector = get_snap_vector (p, *dr_snap, M_PI/snaps, 0);
 681                 }
 682             }
 683             if (snap_vector) {
 684                 snap_vectors = g_slist_prepend (snap_vectors, snap_vector);
 685             }
 686         }
 687
 688         // Move by the smallest of snap vectors:
 689         NR::Point move(9999, 9999);
 690         for (GSList const *i = snap_vectors; i != NULL; i = i->next) {
 691             NR::Point *snap_vector = (NR::Point *) i->data;
 692             if (NR::L2(*snap_vector) < NR::L2(move))
 693                 move = *snap_vector;
 694         }
 695         if (move[NR::X] < 9999) {
 696             p += move;
 697             sp_knot_moveto (knot, &p);
 698         }
 699
 700         g_slist_free(snap_vectors);
 701     }
 702
 703     drag->keep_selection = (bool) g_list_find(drag->selected, dragger);
 704     bool scale_radial = (state & GDK_CONTROL_MASK) && (state & GDK_SHIFT_MASK);
 705
 706     if (drag->keep_selection) {
 707         NR::Point diff = p - dragger->point;
 708         drag->selected_move_nowrite (diff[NR::X], diff[NR::Y], scale_radial);
 709     } else {
 710         dragger->point = p;
 711         dragger->fireDraggables (false, scale_radial);
 712         dragger->updateDependencies(false);
 713     }
 714
 715 }
 716
 717
 718 static void
 719 gr_midpoint_limits(GrDragger *dragger, SPObject *server, NR::Point *begin, NR::Point *end, NR::Point *low_lim, NR::Point *high_lim, GSList **moving)
 720 {
 721
 722     GrDrag *drag = dragger->parent;
 723     // a midpoint dragger can (logically) only contain one GrDraggable
 724     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 725
 726     // get begin and end points between which dragging is allowed:
 727     // the draglimits are between knot(lowest_i - 1) and knot(highest_i + 1)
 728     *moving = g_slist_append(*moving, dragger);
 729
 730     guint lowest_i = draggable->point_i;
 731     guint highest_i = draggable->point_i;
 732     GrDragger *lowest_dragger = dragger;
 733     GrDragger *highest_dragger = dragger;
 734     if (dragger->isSelected()) {
 735         GrDragger* d_add;
 736         while ( true )
 737         {
 738             d_add = drag->getDraggerFor(draggable->item, draggable->point_type, lowest_i - 1, draggable->fill_or_stroke);
 739             if ( d_add && g_list_find(drag->selected, d_add) ) {
 740                 lowest_i = lowest_i - 1;
 741                 *moving = g_slist_prepend(*moving, d_add);
 742                 lowest_dragger = d_add;
 743             } else {
 744                 break;
 745             }
 746         }
 747
 748         while ( true )
 749         {
 750             d_add = drag->getDraggerFor(draggable->item, draggable->point_type, highest_i + 1, draggable->fill_or_stroke);
 751             if ( d_add && g_list_find(drag->selected, d_add) ) {
 752                 highest_i = highest_i + 1;
 753                 *moving = g_slist_append(*moving, d_add);
 754                 highest_dragger = d_add;
 755             } else {
 756                 break;
 757             }
 758         }
 759     }
 760
 761     if ( SP_IS_LINEARGRADIENT(server) ) {
 762         guint num = SP_LINEARGRADIENT(server)->vector.stops.size();
 763         GrDragger *d_temp;
 764         if (lowest_i == 1) {
 765             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_BEGIN, 0, draggable->fill_or_stroke);
 766         } else {
 767             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_MID, lowest_i - 1, draggable->fill_or_stroke);
 768         }
 769         if (d_temp)
 770             *begin = d_temp->point;
 771
 772         d_temp = drag->getDraggerFor (draggable->item, POINT_LG_MID, highest_i + 1, draggable->fill_or_stroke);
 773         if (d_temp == NULL) {
 774             d_temp = drag->getDraggerFor (draggable->item, POINT_LG_END, num-1, draggable->fill_or_stroke);
 775         }
 776         if (d_temp)
 777             *end = d_temp->point;
 778     } else if ( SP_IS_RADIALGRADIENT(server) ) {
 779         guint num = SP_RADIALGRADIENT(server)->vector.stops.size();
 780         GrDragger *d_temp;
 781         if (lowest_i == 1) {
 782             d_temp = drag->getDraggerFor (draggable->item, POINT_RG_CENTER, 0, draggable->fill_or_stroke);
 783         } else {
 784             d_temp = drag->getDraggerFor (draggable->item, draggable->point_type, lowest_i - 1, draggable->fill_or_stroke);
 785         }
 786         if (d_temp)
 787             *begin = d_temp->point;
 788
 789         d_temp = drag->getDraggerFor (draggable->item, draggable->point_type, highest_i + 1, draggable->fill_or_stroke);
 790         if (d_temp == NULL) {
 791             d_temp = drag->getDraggerFor (draggable->item, (draggable->point_type==POINT_RG_MID1) ? POINT_RG_R1 : POINT_RG_R2, num-1, draggable->fill_or_stroke);
 792         }
 793         if (d_temp)
 794             *end = d_temp->point;
 795     }
 796
 797     *low_lim  = dragger->point - (lowest_dragger->point - *begin);
 798     *high_lim = dragger->point - (highest_dragger->point - *end);
 799 }
 800
 801
 802
 803 /**
 804 Called when a midpoint knot is dragged.
 805 */
 806 static void
 807 gr_knot_moved_midpoint_handler(SPKnot *knot, NR::Point const *ppointer, guint state, gpointer data)
 808 {
 809     GrDragger *dragger = (GrDragger *) data;
 810     GrDrag *drag = dragger->parent;
 811     // a midpoint dragger can (logically) only contain one GrDraggable
 812     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 813
 814     // FIXME: take from prefs
 815     double snap_fraction = 0.1;
 816
 817     NR::Point p = *ppointer;
 818     NR::Point begin(0,0), end(0,0);
 819     NR::Point low_lim(0,0), high_lim(0,0);
 820
 821     SPObject *server = draggable->getServer();
 822
 823     GSList *moving = NULL;
 824     gr_midpoint_limits(dragger, server, &begin, &end, &low_lim, &high_lim, &moving);
 825
 826     if (state & GDK_CONTROL_MASK) {
 827         p = snap_vector_midpoint (p, low_lim, high_lim, snap_fraction);
 828     } else {
 829         p = snap_vector_midpoint (p, low_lim, high_lim, 0);
 830     }
 831     NR::Point displacement = p - dragger->point;
 832
 833     for (GSList const* i = moving; i != NULL; i = i->next) {
 834         GrDragger *drg = (GrDragger*) i->data;
 835         SPKnot *drgknot = drg->knot;
 836         NR::Point this_move = displacement;
 837         if (state & GDK_MOD1_MASK) {
 838             // FIXME: unify all these profiles (here, in nodepath, in tweak) in one place
 839             double alpha = 1.5;
 840             if (NR::L2(drg->point - dragger->point) + NR::L2(drg->point - begin) - 1e-3 > NR::L2(dragger->point - begin)) { // drg is on the end side from dragger
 841                 double x = NR::L2(drg->point - dragger->point)/NR::L2(end - dragger->point);
 842                 this_move = (0.5 * cos (M_PI * (pow(x, alpha))) + 0.5) * this_move;
 843             } else { // drg is on the begin side from dragger
 844                 double x = NR::L2(drg->point - dragger->point)/NR::L2(begin - dragger->point);
 845                 this_move = (0.5 * cos (M_PI * (pow(x, alpha))) + 0.5) * this_move;
 846             }
 847         }
 848         drg->point += this_move;
 849         sp_knot_moveto (drgknot, & drg->point);
 850         drg->fireDraggables (false);
 851         drg->updateDependencies(false);
 852     }
 853
 854     g_slist_free(moving);
 855
 856     drag->keep_selection = dragger->isSelected();
 857 }
 858
 859
 860
 861 static void
 862 gr_knot_grabbed_handler (SPKnot *knot, unsigned int state, gpointer data)
 863 {
 864     GrDragger *dragger = (GrDragger *) data;
 865
 866     sp_canvas_force_full_redraw_after_interruptions(dragger->parent->desktop->canvas, 5);
 867 }
 868
 869 /**
 870 Called when the mouse releases a dragger knot; changes gradient writing to repr, updates other draggers if needed
 871 */
 872 static void
 873 gr_knot_ungrabbed_handler (SPKnot *knot, unsigned int state, gpointer data)
 874 {
 875     GrDragger *dragger = (GrDragger *) data;
 876
 877     sp_canvas_end_forced_full_redraws(dragger->parent->desktop->canvas);
 878
 879     dragger->point_original = dragger->point = knot->pos;
 880
 881     if ((state & GDK_CONTROL_MASK) && (state & GDK_SHIFT_MASK)) {
 882         dragger->fireDraggables (true, true);
 883     } else {
 884         dragger->fireDraggables (true);
 885     }
 886
 887     for (GList *i = dragger->parent->selected; i != NULL; i = i->next) {
 888         GrDragger *d = (GrDragger *) i->data;
 889         if (d == dragger)
 890             continue;
 891         d->fireDraggables (true);
 892     }
 893
 894     // make this dragger selected
 895     if (!dragger->parent->keep_selection) {
 896         dragger->parent->setSelected (dragger);
 897     }
 898     dragger->parent->keep_selection = false;
 899
 900     dragger->updateDependencies(true);
 901
 902     // we did an undoable action
 903     sp_document_done (sp_desktop_document (dragger->parent->desktop), SP_VERB_CONTEXT_GRADIENT,
 904                       _("Move gradient handle"));
 905 }
 906
 907 /**
 908 Called when a dragger knot is clicked; selects the dragger or deletes it depending on the
 909 state of the keyboard keys
 910 */
 911 static void
 912 gr_knot_clicked_handler(SPKnot *knot, guint state, gpointer data)
 913 {
 914     GrDragger *dragger = (GrDragger *) data;
 915     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 916     if (!draggable) return;
 917
 918     if ( (state & GDK_CONTROL_MASK) && (state & GDK_MOD1_MASK ) ) {
 919     // delete this knot from vector
 920         SPGradient *gradient = sp_item_gradient (draggable->item, draggable->fill_or_stroke);
 921         gradient = sp_gradient_get_vector (gradient, false);
 922         if (gradient->vector.stops.size() > 2) { // 2 is the minimum
 923                 SPStop *stop = NULL;
 924                 switch (draggable->point_type) {  // if we delete first or last stop, move the next/previous to the edge
 925                 case POINT_LG_BEGIN:
 926                 case POINT_RG_CENTER:
 927                     stop = sp_first_stop(gradient);
 928                         {
 929                             SPStop *next = sp_next_stop (stop);
 930                                 if (next) {
 931                                         next->offset = 0;
 932                                         sp_repr_set_css_double (SP_OBJECT_REPR (next), "offset", 0);
 933                                 }
 934                         }
 935                     break;
 936                 case POINT_LG_END:
 937                 case POINT_RG_R1:
 938                 case POINT_RG_R2:
 939                     stop = sp_last_stop(gradient);
 940                     {
 941                             SPStop *prev = sp_prev_stop (stop, gradient);
 942                             if (prev) {
 943                                     prev->offset = 1;
 944                                     sp_repr_set_css_double (SP_OBJECT_REPR (prev), "offset", 1);
 945                             }
 946                         }
 947                     break;
 948                 case POINT_LG_MID:
 949                 case POINT_RG_MID1:
 950                 case POINT_RG_MID2:
 951                     stop = sp_get_stop_i(gradient, draggable->point_i);
 952                     break;
 953                 }
 954
 955                 SP_OBJECT_REPR(gradient)->removeChild(SP_OBJECT_REPR(stop));
 956                 sp_document_done (SP_OBJECT_DOCUMENT (gradient), SP_VERB_CONTEXT_GRADIENT,
 957                                   _("Delete gradient stop"));
 958         }
 959     } else {
 960     // select the dragger
 961         dragger->point_original = dragger->point;
 962
 963         if ( state & GDK_SHIFT_MASK ) {
 964             dragger->parent->setSelected (dragger, true, false);
 965         } else {
 966             dragger->parent->setSelected (dragger);
 967         }
 968     }
 969 }
 970
 971 /**
 972 Called when a dragger knot is doubleclicked; opens gradient editor with the stop from the first draggable
 973 */
 974 static void
 975 gr_knot_doubleclicked_handler (SPKnot *knot, guint state, gpointer data)
 976 {
 977     GrDragger *dragger = (GrDragger *) data;
 978
 979     dragger->point_original = dragger->point;
 980
 981     if (dragger->draggables == NULL)
 982         return;
 983
 984     GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
 985     sp_item_gradient_edit_stop (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
 986 }
 987
 988 /**
 989 Act upon all draggables of the dragger, setting them to the dragger's point
 990 */
 991 void
 992 GrDragger::fireDraggables (bool write_repr, bool scale_radial, bool merging_focus)
 993 {
 994     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
 995         GrDraggable *draggable = (GrDraggable *) i->data;
 996
 997         // set local_change flag so that selection_changed callback does not regenerate draggers
 998         this->parent->local_change = true;
 999
1000         // change gradient, optionally writing to repr; prevent focus from moving if it's snapped
1001         // to the center, unless it's the first update upon merge when we must snap it to the point
1002         if (merging_focus ||
1003             !(draggable->point_type == POINT_RG_FOCUS && this->isA(draggable->item, POINT_RG_CENTER, draggable->point_i, draggable->fill_or_stroke)))
1004         {
1005             sp_item_gradient_set_coords (draggable->item, draggable->point_type, draggable->point_i, this->point, draggable->fill_or_stroke, write_repr, scale_radial);
1006         }
1007     }
1008 }
1009
1010 /**
1011 Checks if the dragger has a draggable with this point_type
1012  */
1013 bool
1014 GrDragger::isA (gint point_type)
1015 {
1016     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1017         GrDraggable *draggable = (GrDraggable *) i->data;
1018         if (draggable->point_type == point_type) {
1019             return true;
1020         }
1021     }
1022     return false;
1023 }
1024
1025 /**
1026 Checks if the dragger has a draggable with this item, point_type + point_i (number), fill_or_stroke
1027  */
1028 bool
1029 GrDragger::isA (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke)
1030 {
1031     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1032         GrDraggable *draggable = (GrDraggable *) i->data;
1033         if ( (draggable->point_type == point_type) && (draggable->point_i == point_i) && (draggable->item == item) && (draggable->fill_or_stroke == fill_or_stroke) ) {
1034             return true;
1035         }
1036     }
1037     return false;
1038 }
1039
1040 /**
1041 Checks if the dragger has a draggable with this item, point_type, fill_or_stroke
1042  */
1043 bool
1044 GrDragger::isA (SPItem *item, gint point_type, bool fill_or_stroke)
1045 {
1046     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1047         GrDraggable *draggable = (GrDraggable *) i->data;
1048         if ( (draggable->point_type == point_type) && (draggable->item == item) && (draggable->fill_or_stroke == fill_or_stroke) ) {
1049             return true;
1050         }
1051     }
1052     return false;
1053 }
1054
1055 bool
1056 GrDraggable::mayMerge (GrDraggable *da2)
1057 {
1058     if ((this->item == da2->item) && (this->fill_or_stroke == da2->fill_or_stroke)) {
1059         // we must not merge the points of the same gradient!
1060         if (!((this->point_type == POINT_RG_FOCUS && da2->point_type == POINT_RG_CENTER) ||
1061               (this->point_type == POINT_RG_CENTER && da2->point_type == POINT_RG_FOCUS))) {
1062             // except that we can snap center and focus together
1063             return false;
1064         }
1065     }
1066     // disable merging of midpoints.
1067     if ( (this->point_type == POINT_LG_MID) || (da2->point_type == POINT_LG_MID)
1068          || (this->point_type == POINT_RG_MID1) || (da2->point_type == POINT_RG_MID1)
1069          || (this->point_type == POINT_RG_MID2) || (da2->point_type == POINT_RG_MID2) )
1070         return false;
1071
1072     return true;
1073 }
1074
1075 bool
1076 GrDragger::mayMerge (GrDragger *other)
1077 {
1078     if (this == other)
1079         return false;
1080
1081     for (GSList const* i = this->draggables; i != NULL; i = i->next) { // for all draggables of this
1082         GrDraggable *da1 = (GrDraggable *) i->data;
1083         for (GSList const* j = other->draggables; j != NULL; j = j->next) { // for all draggables of other
1084             GrDraggable *da2 = (GrDraggable *) j->data;
1085             if (!da1->mayMerge(da2))
1086                 return false;
1087         }
1088     }
1089     return true;
1090 }
1091
1092 bool
1093 GrDragger::mayMerge (GrDraggable *da2)
1094 {
1095     for (GSList const* i = this->draggables; i != NULL; i = i->next) { // for all draggables of this
1096         GrDraggable *da1 = (GrDraggable *) i->data;
1097         if (!da1->mayMerge(da2))
1098             return false;
1099     }
1100     return true;
1101 }
1102
1103 /**
1104 Updates the statusbar tip of the dragger knot, based on its draggables
1105  */
1106 void
1107 GrDragger::updateTip ()
1108 {
1109         if (this->knot && this->knot->tip) {
1110                 g_free (this->knot->tip);
1111                 this->knot->tip = NULL;
1112         }
1113
1114     if (g_slist_length (this->draggables) == 1) {
1115         GrDraggable *draggable = (GrDraggable *) this->draggables->data;
1116         char *item_desc = sp_item_description(draggable->item);
1117         switch (draggable->point_type) {
1118             case POINT_LG_MID:
1119             case POINT_RG_MID1:
1120             case POINT_RG_MID2:
1121                 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"),
1122                                                    _(gr_knot_descr[draggable->point_type]),
1123                                                    draggable->point_i,
1124                                                    item_desc,
1125                                                    draggable->fill_or_stroke == false ? _(" (stroke)") : "");
1126                 break;
1127
1128             default:
1129                 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"),
1130                                                    _(gr_knot_descr[draggable->point_type]),
1131                                                    item_desc,
1132                                                    draggable->fill_or_stroke == false ? _(" (stroke)") : "");
1133                 break;
1134         }
1135         g_free(item_desc);
1136     } else if (g_slist_length (draggables) == 2 && isA (POINT_RG_CENTER) && isA (POINT_RG_FOCUS)) {
1137         this->knot->tip = g_strdup_printf (_("Radial gradient <b>center</b> and <b>focus</b>; drag with <b>Shift</b> to separate focus"));
1138     } else {
1139         int length = g_slist_length (this->draggables);
1140         this->knot->tip = g_strdup_printf (ngettext("Gradient point shared by <b>%d</b> gradient; drag with <b>Shift</b> to separate",
1141                                                     "Gradient point shared by <b>%d</b> gradients; drag with <b>Shift</b> to separate",
1142                                                     length),
1143                                            length);
1144     }
1145 }
1146
1147 /**
1148 Adds a draggable to the dragger
1149  */
1150 void
1151 GrDragger::updateKnotShape ()
1152 {
1153     if (!draggables)
1154         return;
1155     GrDraggable *last = (GrDraggable *) g_slist_last(draggables)->data;
1156     g_object_set (G_OBJECT (this->knot->item), "shape", gr_knot_shapes[last->point_type], NULL);
1157 }
1158
1159 /**
1160 Adds a draggable to the dragger
1161  */
1162 void
1163 GrDragger::addDraggable (GrDraggable *draggable)
1164 {
1165     this->draggables = g_slist_prepend (this->draggables, draggable);
1166
1167     this->updateTip();
1168 }
1169
1170
1171 /**
1172 Moves this dragger to the point of the given draggable, acting upon all other draggables
1173  */
1174 void
1175 GrDragger::moveThisToDraggable (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, bool write_repr)
1176 {
1177     this->point = sp_item_gradient_get_coords (item, point_type, point_i, fill_or_stroke);
1178     this->point_original = this->point;
1179
1180     sp_knot_moveto (this->knot, &(this->point));
1181
1182     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1183         GrDraggable *da = (GrDraggable *) i->data;
1184         if ( (da->item == item) &&
1185              (point_type == -1 || da->point_type == point_type) &&
1186              (point_i == -1 || da->point_i == point_i) &&
1187              (da->fill_or_stroke == fill_or_stroke) ) {
1188             continue;
1189         }
1190         sp_item_gradient_set_coords (da->item, da->point_type, da->point_i, this->point, da->fill_or_stroke, write_repr, false);
1191     }
1192     // FIXME: here we should also call this->updateDependencies(write_repr); to propagate updating, but how to prevent loops?
1193 }
1194
1195
1196 /**
1197 Moves all midstop draggables that depend on this one
1198  */
1199 void
1200 GrDragger::updateMidstopDependencies (GrDraggable *draggable, bool write_repr) {
1201     SPObject *server = draggable->getServer();
1202     if (!server)
1203         return;
1204     guint num = SP_GRADIENT(server)->vector.stops.size();
1205     if (num <= 2) return;
1206
1207     if ( SP_IS_LINEARGRADIENT(server) ) {
1208         for ( guint i = 1; i < num - 1; i++ ) {
1209             this->moveOtherToDraggable (draggable->item, POINT_LG_MID, i, draggable->fill_or_stroke, write_repr);
1210         }
1211     } else  if ( SP_IS_RADIALGRADIENT(server) ) {
1212         for ( guint i = 1; i < num - 1; i++ ) {
1213             this->moveOtherToDraggable (draggable->item, POINT_RG_MID1, i, draggable->fill_or_stroke, write_repr);
1214             this->moveOtherToDraggable (draggable->item, POINT_RG_MID2, i, draggable->fill_or_stroke, write_repr);
1215         }
1216     }
1217 }
1218
1219
1220 /**
1221 Moves all draggables that depend on this one
1222  */
1223 void
1224 GrDragger::updateDependencies (bool write_repr)
1225 {
1226     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1227         GrDraggable *draggable = (GrDraggable *) i->data;
1228         switch (draggable->point_type) {
1229             case POINT_LG_BEGIN:
1230                 {
1231                     // the end point is dependent only when dragging with ctrl+shift
1232                     this->moveOtherToDraggable (draggable->item, POINT_LG_END, -1, draggable->fill_or_stroke, write_repr);
1233
1234                     this->updateMidstopDependencies (draggable, write_repr);
1235                 }
1236                 break;
1237             case POINT_LG_END:
1238                 {
1239                     // the begin point is dependent only when dragging with ctrl+shift
1240                     this->moveOtherToDraggable (draggable->item, POINT_LG_BEGIN, 0, draggable->fill_or_stroke, write_repr);
1241
1242                     this->updateMidstopDependencies (draggable, write_repr);
1243                 }
1244                 break;
1245             case POINT_LG_MID:
1246                 // no other nodes depend on mid points.
1247                 break;
1248             case POINT_RG_R2:
1249                 this->moveOtherToDraggable (draggable->item, POINT_RG_R1, -1, draggable->fill_or_stroke, write_repr);
1250                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1251                 this->updateMidstopDependencies (draggable, write_repr);
1252                 break;
1253             case POINT_RG_R1:
1254                 this->moveOtherToDraggable (draggable->item, POINT_RG_R2, -1, draggable->fill_or_stroke, write_repr);
1255                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1256                 this->updateMidstopDependencies (draggable, write_repr);
1257                 break;
1258             case POINT_RG_CENTER:
1259                 this->moveOtherToDraggable (draggable->item, POINT_RG_R1, -1, draggable->fill_or_stroke, write_repr);
1260                 this->moveOtherToDraggable (draggable->item, POINT_RG_R2, -1, draggable->fill_or_stroke, write_repr);
1261                 this->moveOtherToDraggable (draggable->item, POINT_RG_FOCUS, -1, draggable->fill_or_stroke, write_repr);
1262                 this->updateMidstopDependencies (draggable, write_repr);
1263                 break;
1264             case POINT_RG_FOCUS:
1265                 // nothing can depend on that
1266                 break;
1267             case POINT_RG_MID1:
1268                 this->moveOtherToDraggable (draggable->item, POINT_RG_MID2, draggable->point_i, draggable->fill_or_stroke, write_repr);
1269                 break;
1270             case POINT_RG_MID2:
1271                 this->moveOtherToDraggable (draggable->item, POINT_RG_MID1, draggable->point_i, draggable->fill_or_stroke, write_repr);
1272                 break;
1273             default:
1274                 break;
1275         }
1276     }
1277 }
1278
1279
1280
1281 GrDragger::GrDragger (GrDrag *parent, NR::Point p, GrDraggable *draggable)
1282 {
1283     this->draggables = NULL;
1284
1285     this->parent = parent;
1286
1287     this->point = p;
1288     this->point_original = p;
1289
1290     // create the knot
1291     this->knot = sp_knot_new (parent->desktop, NULL);
1292     this->knot->setMode(SP_KNOT_MODE_XOR);
1293     this->knot->setFill(GR_KNOT_COLOR_NORMAL, GR_KNOT_COLOR_MOUSEOVER, GR_KNOT_COLOR_MOUSEOVER);
1294     this->knot->setStroke(0x000000ff, 0x000000ff, 0x000000ff);
1295     sp_knot_update_ctrl(this->knot);
1296
1297     // move knot to the given point
1298     sp_knot_set_position (this->knot, &p, SP_KNOT_STATE_NORMAL);
1299     sp_knot_show (this->knot);
1300
1301     // connect knot's signals
1302     if ( (draggable)  // it can be NULL if a node in unsnapped (eg. focus point unsnapped from center)
1303                        // luckily, midstops never snap to other nodes so are never unsnapped...
1304          && ( (draggable->point_type == POINT_LG_MID)
1305               || (draggable->point_type == POINT_RG_MID1)
1306               || (draggable->point_type == POINT_RG_MID2) ) )
1307     {
1308         this->handler_id = g_signal_connect (G_OBJECT (this->knot), "moved", G_CALLBACK (gr_knot_moved_midpoint_handler), this);
1309     } else {
1310         this->handler_id = g_signal_connect (G_OBJECT (this->knot), "moved", G_CALLBACK (gr_knot_moved_handler), this);
1311     }
1312     g_signal_connect (G_OBJECT (this->knot), "clicked", G_CALLBACK (gr_knot_clicked_handler), this);
1313     g_signal_connect (G_OBJECT (this->knot), "doubleclicked", G_CALLBACK (gr_knot_doubleclicked_handler), this);
1314     g_signal_connect (G_OBJECT (this->knot), "grabbed", G_CALLBACK (gr_knot_grabbed_handler), this);
1315     g_signal_connect (G_OBJECT (this->knot), "ungrabbed", G_CALLBACK (gr_knot_ungrabbed_handler), this);
1316
1317     // add the initial draggable
1318     if (draggable)
1319         this->addDraggable (draggable);
1320     updateKnotShape();
1321 }
1322
1323 GrDragger::~GrDragger ()
1324 {
1325     // unselect if it was selected
1326     this->parent->setDeselected(this);
1327
1328     // disconnect signals
1329     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_moved_handler), this);
1330     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_clicked_handler), this);
1331     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_doubleclicked_handler), this);
1332     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_grabbed_handler), this);
1333     g_signal_handlers_disconnect_by_func(G_OBJECT(this->knot), (gpointer) G_CALLBACK (gr_knot_ungrabbed_handler), this);
1334
1335     /* unref should call destroy */
1336     g_object_unref (G_OBJECT (this->knot));
1337
1338     // delete all draggables
1339     for (GSList const* i = this->draggables; i != NULL; i = i->next) {
1340         delete ((GrDraggable *) i->data);
1341     }
1342     g_slist_free (this->draggables);
1343     this->draggables = NULL;
1344 }
1345
1346 /**
1347 Select the dragger which has the given draggable.
1348 */
1349 GrDragger *
1350 GrDrag::getDraggerFor (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke)
1351 {
1352     for (GList const* i = this->draggers; i != NULL; i = i->next) {
1353         GrDragger *dragger = (GrDragger *) i->data;
1354         for (GSList const* j = dragger->draggables; j != NULL; j = j->next) {
1355             GrDraggable *da2 = (GrDraggable *) j->data;
1356             if ( (da2->item == item) &&
1357                  (point_type == -1 || da2->point_type == point_type) && // -1 means this does not matter
1358                  (point_i == -1 || da2->point_i == point_i) && // -1 means this does not matter
1359                  (da2->fill_or_stroke == fill_or_stroke)) {
1360                 return (dragger);
1361             }
1362         }
1363     }
1364     return NULL;
1365 }
1366
1367
1368 void
1369 GrDragger::moveOtherToDraggable (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, bool write_repr)
1370 {
1371     GrDragger *d = this->parent->getDraggerFor (item, point_type, point_i, fill_or_stroke);
1372     if (d && d !=  this) {
1373         d->moveThisToDraggable (item, point_type, point_i, fill_or_stroke, write_repr);
1374     }
1375 }
1376
1377
1378 /**
1379   Draw this dragger as selected
1380 */
1381 void
1382 GrDragger::select()
1383 {
1384     this->knot->fill [SP_KNOT_STATE_NORMAL] = GR_KNOT_COLOR_SELECTED;
1385     g_object_set (G_OBJECT (this->knot->item), "fill_color", GR_KNOT_COLOR_SELECTED, NULL);
1386 }
1387
1388 /**
1389   Draw this dragger as normal (deselected)
1390 */
1391 void
1392 GrDragger::deselect()
1393 {
1394     this->knot->fill [SP_KNOT_STATE_NORMAL] = GR_KNOT_COLOR_NORMAL;
1395     g_object_set (G_OBJECT (this->knot->item), "fill_color", GR_KNOT_COLOR_NORMAL, NULL);
1396 }
1397
1398 bool
1399 GrDragger::isSelected()
1400 {
1401     return g_list_find (parent->selected, this);
1402 }
1403
1404 /**
1405 \brief Deselect all stops/draggers (private)
1406 */
1407 void
1408 GrDrag::deselect_all()
1409 {
1410     while (selected) {
1411         ( (GrDragger*) selected->data)->deselect();
1412         selected = g_list_remove(selected, selected->data);
1413     }
1414 }
1415
1416 /**
1417 \brief Deselect all stops/draggers (public; emits signal)
1418 */
1419 void
1420 GrDrag::deselectAll()
1421 {
1422     deselect_all();
1423     this->desktop->emitToolSubselectionChanged(NULL);
1424 }
1425
1426 /**
1427 \brief Select all stops/draggers
1428 */
1429 void
1430 GrDrag::selectAll()
1431 {
1432     for (GList *l = this->draggers; l != NULL; l = l->next) {
1433         GrDragger *d = ((GrDragger *) l->data);
1434         setSelected (d, true, true);
1435     }
1436 }
1437
1438 /**
1439 \brief Select all stops/draggers that match the coords
1440 */
1441 void
1442 GrDrag::selectByCoords(std::vector<NR::Point> coords)
1443 {
1444     for (GList *l = this->draggers; l != NULL; l = l->next) {
1445         GrDragger *d = ((GrDragger *) l->data);
1446         for (guint k = 0; k < coords.size(); k++) {
1447             if (NR::L2 (d->point - coords[k]) < 1e-4) {
1448                 setSelected (d, true, true);
1449             }
1450         }
1451     }
1452 }
1453
1454
1455 /**
1456 \brief Select all stops/draggers that fall within the rect
1457 */
1458 void
1459 GrDrag::selectRect(NR::Rect const &r)
1460 {
1461     for (GList *l = this->draggers; l != NULL; l = l->next) {
1462         GrDragger *d = ((GrDragger *) l->data);
1463         if (r.contains(d->point)) {
1464            setSelected (d, true, true);
1465         }
1466     }
1467 }
1468
1469 /**
1470 \brief Select a dragger
1471 \param dragger       The dragger to select
1472 \param add_to_selection   If true, add to selection, otherwise deselect others
1473 \param override      If true, always select this node, otherwise toggle selected status
1474 */
1475 void
1476 GrDrag::setSelected (GrDragger *dragger, bool add_to_selection, bool override)
1477 {
1478     GrDragger *seldragger = NULL;
1479
1480     if (add_to_selection) {
1481         if (!dragger) return;
1482         if (override) {
1483             if (!g_list_find(selected, dragger)) {
1484                 selected = g_list_prepend(selected, dragger);
1485             }
1486             dragger->select();
1487             seldragger = dragger;
1488         } else { // toggle
1489             if (g_list_find(selected, dragger)) {
1490                 selected = g_list_remove(selected, dragger);
1491                 dragger->deselect();
1492                 if (selected) {
1493                     seldragger = (GrDragger*) selected->data; // select the dragger that is first in the list
1494                 }
1495             } else {
1496                 selected = g_list_prepend(selected, dragger);
1497                 dragger->select();
1498                 seldragger = dragger;
1499             }
1500         }
1501     } else {
1502         deselect_all();
1503         if (dragger) {
1504             selected = g_list_prepend(selected, dragger);
1505             dragger->select();
1506             seldragger = dragger;
1507         }
1508     }
1509     if (seldragger) {
1510         this->desktop->emitToolSubselectionChanged((gpointer) seldragger);
1511     }
1512 }
1513
1514 /**
1515 \brief Deselect a dragger
1516 \param dragger       The dragger to deselect
1517 */
1518 void
1519 GrDrag::setDeselected (GrDragger *dragger)
1520 {
1521     if (g_list_find(selected, dragger)) {
1522         selected = g_list_remove(selected, dragger);
1523         dragger->deselect();
1524     }
1525     this->desktop->emitToolSubselectionChanged((gpointer) (selected ? selected->data : NULL ));
1526 }
1527
1528
1529
1530 /**
1531 Create a line from p1 to p2 and add it to the lines list
1532  */
1533 void
1534 GrDrag::addLine (SPItem *item, NR::Point p1, NR::Point p2, guint32 rgba)
1535 {
1536     SPCanvasItem *line = sp_canvas_item_new(sp_desktop_controls(this->desktop),
1537                                                             SP_TYPE_CTRLLINE, NULL);
1538     SP_CTRLLINE(line)->item = item;
1539     sp_ctrlline_set_coords(SP_CTRLLINE(line), p1, p2);
1540     if (rgba != GR_LINE_COLOR_FILL) // fill is the default, so don't set color for it to speed up redraw
1541         sp_ctrlline_set_rgba32 (SP_CTRLLINE(line), rgba);
1542     sp_canvas_item_show (line);
1543     this->lines = g_slist_append (this->lines, line);
1544 }
1545
1546 /**
1547 If there already exists a dragger within MERGE_DIST of p, add the draggable to it; otherwise create
1548 new dragger and add it to draggers list
1549  */
1550 void
1551 GrDrag::addDragger (GrDraggable *draggable)
1552 {
1553     NR::Point p = sp_item_gradient_get_coords (draggable->item, draggable->point_type, draggable->point_i, draggable->fill_or_stroke);
1554
1555     for (GList *i = this->draggers; i != NULL; i = i->next) {
1556         GrDragger *dragger = (GrDragger *) i->data;
1557         if (dragger->mayMerge (draggable) && NR::L2 (dragger->point - p) < MERGE_DIST) {
1558             // distance is small, merge this draggable into dragger, no need to create new dragger
1559             dragger->addDraggable (draggable);
1560             dragger->updateKnotShape();
1561             return;
1562         }
1563     }
1564
1565     GrDragger *new_dragger = new GrDragger(this, p, draggable);
1566     // fixme: draggers should be added AFTER the last one: this way tabbing through them will be from begin to end.
1567     this->draggers = g_list_append (this->draggers, new_dragger);
1568 }
1569
1570 /**
1571 Add draggers for the radial gradient rg on item
1572 */
1573 void
1574 GrDrag::addDraggersRadial (SPRadialGradient *rg, SPItem *item, bool fill_or_stroke)
1575 {
1576     addDragger (new GrDraggable (item, POINT_RG_CENTER, 0, fill_or_stroke));
1577     guint num = rg->vector.stops.size();
1578     if (num > 2) {
1579         for ( guint i = 1; i < num - 1; i++ ) {
1580             addDragger (new GrDraggable (item, POINT_RG_MID1, i, fill_or_stroke));
1581         }
1582     }
1583     addDragger (new GrDraggable (item, POINT_RG_R1, num-1, fill_or_stroke));
1584     if (num > 2) {
1585         for ( guint i = 1; i < num - 1; i++ ) {
1586             addDragger (new GrDraggable (item, POINT_RG_MID2, i, fill_or_stroke));
1587         }
1588     }
1589     addDragger (new GrDraggable (item, POINT_RG_R2, num-1, fill_or_stroke));
1590     addDragger (new GrDraggable (item, POINT_RG_FOCUS, 0, fill_or_stroke));
1591 }
1592
1593 /**
1594 Add draggers for the linear gradient lg on item
1595 */
1596 void
1597 GrDrag::addDraggersLinear (SPLinearGradient *lg, SPItem *item, bool fill_or_stroke)
1598 {
1599     addDragger (new GrDraggable (item, POINT_LG_BEGIN, 0, fill_or_stroke));
1600     guint num = lg->vector.stops.size();
1601     if (num > 2) {
1602         for ( guint i = 1; i < num - 1; i++ ) {
1603             addDragger (new GrDraggable (item, POINT_LG_MID, i, fill_or_stroke));
1604         }
1605     }
1606     addDragger (new GrDraggable (item, POINT_LG_END, num-1, fill_or_stroke));
1607 }
1608
1609 /**
1610 Artificially grab the knot of this dragger; used by the gradient context
1611 */
1612 void
1613 GrDrag::grabKnot (GrDragger *dragger, gint x, gint y, guint32 etime)
1614 {
1615     if (dragger) {
1616         sp_knot_start_dragging (dragger->knot, dragger->point, x, y, etime);
1617     }
1618 }
1619
1620 /**
1621 Artificially grab the knot of the dragger with this draggable; used by the gradient context
1622 */
1623 void
1624 GrDrag::grabKnot (SPItem *item, gint point_type, gint point_i, bool fill_or_stroke, gint x, gint y, guint32 etime)
1625 {
1626     GrDragger *dragger = getDraggerFor (item, point_type, point_i, fill_or_stroke);
1627     if (dragger) {
1628         sp_knot_start_dragging (dragger->knot, dragger->point, x, y, etime);
1629     }
1630 }
1631
1632 /**
1633 Regenerates the draggers list from the current selection; is called when selection is changed or
1634 modified, also when a radial dragger needs to update positions of other draggers in the gradient
1635 */
1636 void
1637 GrDrag::updateDraggers ()
1638 {
1639     while (selected) {
1640         selected = g_list_remove(selected, selected->data);
1641     }
1642     // delete old draggers
1643     for (GList const* i = this->draggers; i != NULL; i = i->next) {
1644         delete ((GrDragger *) i->data);
1645     }
1646     g_list_free (this->draggers);
1647     this->draggers = NULL;
1648
1649     g_return_if_fail (this->selection != NULL);
1650
1651     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1652
1653         SPItem *item = SP_ITEM(i->data);
1654         SPStyle *style = SP_OBJECT_STYLE (item);
1655
1656         if (style && (style->fill.isPaintserver())) {
1657             SPObject *server = SP_OBJECT_STYLE_FILL_SERVER (item);
1658             if (SP_IS_LINEARGRADIENT (server)) {
1659                 addDraggersLinear (SP_LINEARGRADIENT (server), item, true);
1660             } else if (SP_IS_RADIALGRADIENT (server)) {
1661                 addDraggersRadial (SP_RADIALGRADIENT (server), item, true);
1662             }
1663         }
1664
1665         if (style && (style->stroke.isPaintserver())) {
1666             SPObject *server = SP_OBJECT_STYLE_STROKE_SERVER (item);
1667             if (SP_IS_LINEARGRADIENT (server)) {
1668                 addDraggersLinear (SP_LINEARGRADIENT (server), item, false);
1669             } else if (SP_IS_RADIALGRADIENT (server)) {
1670                 addDraggersRadial (SP_RADIALGRADIENT (server), item, false);
1671             }
1672         }
1673     }
1674 }
1675
1676 /**
1677 Regenerates the lines list from the current selection; is called on each move of a dragger, so that
1678 lines are always in sync with the actual gradient
1679 */
1680 void
1681 GrDrag::updateLines ()
1682 {
1683     // delete old lines
1684     for (GSList const *i = this->lines; i != NULL; i = i->next) {
1685         gtk_object_destroy( GTK_OBJECT (i->data));
1686     }
1687     g_slist_free (this->lines);
1688     this->lines = NULL;
1689
1690     g_return_if_fail (this->selection != NULL);
1691
1692     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1693
1694         SPItem *item = SP_ITEM(i->data);
1695
1696         SPStyle *style = SP_OBJECT_STYLE (item);
1697
1698         if (style && (style->fill.isPaintserver())) {
1699             SPObject *server = SP_OBJECT_STYLE_FILL_SERVER (item);
1700             if (SP_IS_LINEARGRADIENT (server)) {
1701                 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);
1702             } else if (SP_IS_RADIALGRADIENT (server)) {
1703                 NR::Point center = sp_item_gradient_get_coords (item, POINT_RG_CENTER, 0, true);
1704                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R1, 0, true), GR_LINE_COLOR_FILL);
1705                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R2, 0, true), GR_LINE_COLOR_FILL);
1706             }
1707         }
1708
1709         if (style && (style->stroke.isPaintserver())) {
1710             SPObject *server = SP_OBJECT_STYLE_STROKE_SERVER (item);
1711             if (SP_IS_LINEARGRADIENT (server)) {
1712                 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);
1713             } else if (SP_IS_RADIALGRADIENT (server)) {
1714                 NR::Point center = sp_item_gradient_get_coords (item, POINT_RG_CENTER, 0, false);
1715                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R1, 0, false), GR_LINE_COLOR_STROKE);
1716                 this->addLine (item, center, sp_item_gradient_get_coords (item, POINT_RG_R2, 0, false), GR_LINE_COLOR_STROKE);
1717             }
1718         }
1719     }
1720 }
1721
1722 /**
1723 Regenerates the levels list from the current selection
1724 */
1725 void
1726 GrDrag::updateLevels ()
1727 {
1728     hor_levels.clear();
1729     vert_levels.clear();
1730
1731     g_return_if_fail (this->selection != NULL);
1732
1733     for (GSList const* i = this->selection->itemList(); i != NULL; i = i->next) {
1734         SPItem *item = SP_ITEM(i->data);
1735         NR::Maybe<NR::Rect> rect = sp_item_bbox_desktop (item);
1736         if (rect) {
1737             // Remember the edges of the bbox and the center axis
1738             hor_levels.push_back(rect->min()[NR::Y]);
1739             hor_levels.push_back(rect->max()[NR::Y]);
1740             hor_levels.push_back(0.5 * (rect->min()[NR::Y] + rect->max()[NR::Y]));
1741             vert_levels.push_back(rect->min()[NR::X]);
1742             vert_levels.push_back(rect->max()[NR::X]);
1743             vert_levels.push_back(0.5 * (rect->min()[NR::X] + rect->max()[NR::X]));
1744         }
1745     }
1746 }
1747
1748 void
1749 GrDrag::selected_reverse_vector ()
1750 {
1751     if (selected == NULL)
1752         return;
1753
1754     for (GSList const* i = ( (GrDragger*) selected->data )->draggables; i != NULL; i = i->next) {
1755         GrDraggable *draggable = (GrDraggable *) i->data;
1756
1757         sp_item_gradient_reverse_vector (draggable->item, draggable->fill_or_stroke);
1758     }
1759 }
1760
1761 void
1762 GrDrag::selected_move_nowrite (double x, double y, bool scale_radial)
1763 {
1764     selected_move (x, y, false, scale_radial);
1765 }
1766
1767 void
1768 GrDrag::selected_move (double x, double y, bool write_repr, bool scale_radial)
1769 {
1770     if (selected == NULL)
1771         return;
1772
1773     bool did = false;
1774
1775     for (GList *i = selected; i != NULL; i = i->next) {
1776         GrDragger *d = (GrDragger *) i->data;
1777
1778         if (!d->isA(POINT_LG_MID) && !d->isA(POINT_RG_MID1) && !d->isA(POINT_RG_MID2)) {
1779             // if this is an endpoint,
1780
1781             // Moving an rg center moves its focus and radii as well.
1782             // therefore, if this is a focus or radius and if selection
1783             // contains the center as well, do not move this one
1784             if (d->isA(POINT_RG_R1) || d->isA(POINT_RG_R2) ||
1785                 (d->isA(POINT_RG_FOCUS) && !d->isA(POINT_RG_CENTER))) {
1786                 bool skip_radius_with_center = false;
1787                 for (GList *di = selected; di != NULL; di = di->next) {
1788                     GrDragger *d_new = (GrDragger *) di->data;
1789                     if (d_new->isA (((GrDraggable *) d->draggables->data)->item,
1790                                     POINT_RG_CENTER,
1791                                     0,
1792                                     ((GrDraggable *) d->draggables->data)->fill_or_stroke)) {
1793                         // FIXME: here we take into account only the first draggable!
1794                         skip_radius_with_center = true;
1795                     }
1796                 }
1797                 if (skip_radius_with_center)
1798                     continue;
1799             }
1800
1801             did = true;
1802             d->point += NR::Point (x, y);
1803             d->point_original = d->point;
1804             sp_knot_moveto (d->knot, &(d->point));
1805
1806             d->fireDraggables (write_repr, scale_radial);
1807
1808             d->updateDependencies(write_repr);
1809         }
1810     }
1811
1812     if (write_repr && did) {
1813         // we did an undoable action
1814         sp_document_maybe_done (sp_desktop_document (desktop), "grmoveh", SP_VERB_CONTEXT_GRADIENT,
1815                                 _("Move gradient handle(s)"));
1816         return;
1817     }
1818
1819     if (!did) { // none of the end draggers are selected, so let's try to move the mids
1820
1821         GrDragger *dragger = (GrDragger *) selected->data;
1822         // a midpoint dragger can (logically) only contain one GrDraggable
1823         GrDraggable *draggable = (GrDraggable *) dragger->draggables->data;
1824
1825         NR::Point begin(0,0), end(0,0);
1826         NR::Point low_lim(0,0), high_lim(0,0);
1827
1828         SPObject *server = draggable->getServer();
1829         GSList *moving = NULL;
1830         gr_midpoint_limits(dragger, server, &begin, &end, &low_lim, &high_lim, &moving);
1831
1832         NR::Point p(x, y);
1833         p = snap_vector_midpoint (dragger->point + p, low_lim, high_lim, 0);
1834         NR::Point displacement = p - dragger->point;
1835
1836         for (GSList const* i = moving; i != NULL; i = i->next) {
1837             GrDragger *drg = (GrDragger*) i->data;
1838             SPKnot *drgknot = drg->knot;
1839             drg->point += displacement;
1840             sp_knot_moveto (drgknot, & drg->point);
1841             drg->fireDraggables (true);
1842             drg->updateDependencies(true);
1843             did = true;
1844         }
1845
1846         g_slist_free(moving);
1847
1848         if (write_repr && did) {
1849             // we did an undoable action
1850             sp_document_maybe_done (sp_desktop_document (desktop), "grmovem", SP_VERB_CONTEXT_GRADIENT,
1851                                     _("Move gradient mid stop(s)"));
1852         }
1853     }
1854 }
1855
1856 void
1857 GrDrag::selected_move_screen (double x, double y)
1858 {
1859     gdouble zoom = desktop->current_zoom();
1860     gdouble zx = x / zoom;
1861     gdouble zy = y / zoom;
1862
1863     selected_move (zx, zy);
1864 }
1865
1866 /**
1867 Select the knot next to the last selected one and deselect all other selected.
1868 */
1869 GrDragger *
1870 GrDrag::select_next ()
1871 {
1872     GrDragger *d = NULL;
1873     if (selected == NULL || g_list_find(draggers, selected->data)->next == NULL) {
1874         if (draggers)
1875             d = (GrDragger *) draggers->data;
1876     } else {
1877         d = (GrDragger *) g_list_find(draggers, selected->data)->next->data;
1878     }
1879     if (d)
1880         setSelected (d);
1881     return d;
1882 }
1883
1884 /**
1885 Select the knot previous from the last selected one and deselect all other selected.
1886 */
1887 GrDragger *
1888 GrDrag::select_prev ()
1889 {
1890     GrDragger *d = NULL;
1891     if (selected == NULL || g_list_find(draggers, selected->data)->prev == NULL) {
1892         if (draggers)
1893             d = (GrDragger *) g_list_last (draggers)->data;
1894     } else {
1895         d = (GrDragger *) g_list_find(draggers, selected->data)->prev->data;
1896     }
1897     if (d)
1898         setSelected (d);
1899     return d;
1900 }
1901
1902
1903 // FIXME: i.m.o. an ugly function that I just made to work, but... aargh! (Johan)
1904 void
1905 GrDrag::deleteSelected (bool just_one)
1906 {
1907     if (!selected) return;
1908
1909     SPDocument *document = false;
1910
1911     struct StructStopInfo {
1912         SPStop * spstop;
1913         GrDraggable * draggable;
1914         SPGradient * gradient;
1915         SPGradient * vector;
1916     };
1917
1918     GSList *midstoplist = NULL;  // list of stops that must be deleted (will be deleted first)
1919     GSList *endstoplist = NULL;  // list of stops that must be deleted
1920     while (selected) {
1921         GrDragger *dragger = (GrDragger*) selected->data;
1922         for (GSList * drgble = dragger->draggables; drgble != NULL; drgble = drgble->next) {
1923             GrDraggable *draggable = (GrDraggable*) drgble->data;
1924             SPGradient *gradient = sp_item_gradient (draggable->item, draggable->fill_or_stroke);
1925             SPGradient *vector   = sp_gradient_get_forked_vector_if_necessary (gradient, false);
1926
1927             switch (draggable->point_type) {
1928                 case POINT_LG_MID:
1929                 case POINT_RG_MID1:
1930                 case POINT_RG_MID2:
1931                     {
1932                         SPStop *stop = sp_get_stop_i(vector, draggable->point_i);
1933                         // check if already present in list. (e.g. when both RG_MID1 and RG_MID2 were selected)
1934                         bool present = false;
1935                         for (GSList const * l = midstoplist; l != NULL; l = l->next) {
1936                             if ( (SPStop*)l->data == stop ) {
1937                                 present = true;
1938                                 break; // no need to search further.
1939                             }
1940                         }
1941                         if (!present)
1942                             midstoplist = g_slist_append(midstoplist, stop);
1943                     }
1944                     break;
1945                 case POINT_LG_BEGIN:
1946                 case POINT_LG_END:
1947                 case POINT_RG_CENTER:
1948                 case POINT_RG_R1:
1949                 case POINT_RG_R2:
1950                     {
1951                         SPStop *stop = NULL;
1952                         if ( (draggable->point_type == POINT_LG_BEGIN) || (draggable->point_type == POINT_RG_CENTER) ) {
1953                             stop = sp_first_stop(vector);
1954                         } else {
1955                             stop = sp_last_stop(vector);
1956                         }
1957                         if (stop) {
1958                             StructStopInfo *stopinfo = new StructStopInfo;
1959                             stopinfo->spstop = stop;
1960                             stopinfo->draggable = draggable;
1961                             stopinfo->gradient = gradient;
1962                             stopinfo->vector = vector;
1963                             // check if already present in list. (e.g. when both R1 and R2 were selected)
1964                             bool present = false;
1965                             for (GSList const * l = endstoplist; l != NULL; l = l->next) {
1966                                 if ( ((StructStopInfo*)l->data)->spstop == stopinfo->spstop ) {
1967                                     present = true;
1968                                     break; // no need to search further.
1969                                 }
1970                             }
1971                             if (!present)
1972                                 endstoplist = g_slist_append(endstoplist, stopinfo);
1973                         }
1974                     }
1975                     break;
1976                 default:
1977                     break;
1978             }
1979         }
1980         selected = g_list_remove(selected, dragger);
1981         if ( just_one ) break; // iterate once if just_one is set.
1982     }
1983     while (midstoplist) {
1984         SPStop *stop = (SPStop*) midstoplist->data;
1985         document = SP_OBJECT_DOCUMENT (stop);
1986         Inkscape::XML::Node * parent = SP_OBJECT_REPR(stop)->parent();
1987         parent->removeChild(SP_OBJECT_REPR(stop));
1988         midstoplist = g_slist_remove(midstoplist, stop);
1989     }
1990     while (endstoplist) {
1991         StructStopInfo *stopinfo  = (StructStopInfo*) endstoplist->data;
1992         document = SP_OBJECT_DOCUMENT (stopinfo->spstop);
1993
1994         // 2 is the minimum, cannot delete more than that without deleting the whole vector
1995         // cannot use vector->vector.stops.size() because the vector might be invalidated by deletion of a midstop
1996         // manually count the children, don't know if there already exists a function for this...
1997         int len = 0;
1998         for ( SPObject *child = sp_object_first_child(stopinfo->vector) ;
1999               child != NULL ;
2000               child = SP_OBJECT_NEXT(child) )
2001         {
2002             if ( SP_IS_STOP(child) )  len ++;
2003         }
2004         if (len > 2)
2005         {
2006             switch (stopinfo->draggable->point_type) {
2007                 case POINT_LG_BEGIN:
2008                     {
2009                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2010
2011                         SPLinearGradient *lg = SP_LINEARGRADIENT(stopinfo->gradient);
2012                         NR::Point oldbegin = NR::Point (lg->x1.computed, lg->y1.computed);
2013                         NR::Point end = NR::Point (lg->x2.computed, lg->y2.computed);
2014                         SPStop *stop = sp_first_stop(stopinfo->vector);
2015                         gdouble offset = stop->offset;
2016                         NR::Point newbegin = oldbegin + offset * (end - oldbegin);
2017                         lg->x1.computed = newbegin[NR::X];
2018                         lg->y1.computed = newbegin[NR::Y];
2019
2020                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(stopinfo->gradient);
2021                         sp_repr_set_svg_double(repr, "x1", lg->x1.computed);
2022                         sp_repr_set_svg_double(repr, "y1", lg->y1.computed);
2023                         stop->offset = 0;
2024                         sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", 0);
2025
2026                         // iterate through midstops to set new offset values such that they won't move on canvas.
2027                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2028                         stop = sp_next_stop(stop);
2029                         while ( stop != laststop ) {
2030                             stop->offset = (stop->offset - offset)/(1 - offset);
2031                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2032                             stop = sp_next_stop(stop);
2033                         }
2034                     }
2035                     break;
2036                 case POINT_LG_END:
2037                     {
2038                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2039
2040                         SPLinearGradient *lg = SP_LINEARGRADIENT(stopinfo->gradient);
2041                         NR::Point begin = NR::Point (lg->x1.computed, lg->y1.computed);
2042                         NR::Point oldend = NR::Point (lg->x2.computed, lg->y2.computed);
2043                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2044                         gdouble offset = laststop->offset;
2045                         NR::Point newend = begin + offset * (oldend - begin);
2046                         lg->x2.computed = newend[NR::X];
2047                         lg->y2.computed = newend[NR::Y];
2048
2049                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(stopinfo->gradient);
2050                         sp_repr_set_svg_double(repr, "x2", lg->x2.computed);
2051                         sp_repr_set_svg_double(repr, "y2", lg->y2.computed);
2052                         laststop->offset = 1;
2053                         sp_repr_set_css_double (SP_OBJECT_REPR (laststop), "offset", 1);
2054
2055                         // iterate through midstops to set new offset values such that they won't move on canvas.
2056                         SPStop *stop = sp_first_stop(stopinfo->vector);
2057                         stop = sp_next_stop(stop);
2058                         while ( stop != laststop ) {
2059                             stop->offset = stop->offset / offset;
2060                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2061                             stop = sp_next_stop(stop);
2062                         }
2063                     }
2064                     break;
2065                 case POINT_RG_CENTER:
2066                     {
2067                         SPStop *newfirst = sp_next_stop (stopinfo->spstop);
2068                         if (newfirst) {
2069                             newfirst->offset = 0;
2070                             sp_repr_set_css_double (SP_OBJECT_REPR (newfirst), "offset", 0);
2071                         }
2072                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2073                     }
2074                     break;
2075                 case POINT_RG_R1:
2076                 case POINT_RG_R2:
2077                         SP_OBJECT_REPR(stopinfo->vector)->removeChild(SP_OBJECT_REPR(stopinfo->spstop));
2078
2079                         SPRadialGradient *rg = SP_RADIALGRADIENT(stopinfo->gradient);
2080                         double oldradius = rg->r.computed;
2081                         SPStop *laststop = sp_last_stop(stopinfo->vector);
2082                         gdouble offset = laststop->offset;
2083                         double newradius = offset * oldradius;
2084                         rg->r.computed = newradius;
2085
2086                         Inkscape::XML::Node *repr = SP_OBJECT_REPR(rg);
2087                         sp_repr_set_svg_double(repr, "r", rg->r.computed);
2088                         laststop->offset = 1;
2089                         sp_repr_set_css_double (SP_OBJECT_REPR (laststop), "offset", 1);
2090
2091                         // iterate through midstops to set new offset values such that they won't move on canvas.
2092                         SPStop *stop = sp_first_stop(stopinfo->vector);
2093                         stop = sp_next_stop(stop);
2094                         while ( stop != laststop ) {
2095                             stop->offset = stop->offset / offset;
2096                             sp_repr_set_css_double (SP_OBJECT_REPR (stop), "offset", stop->offset);
2097                             stop = sp_next_stop(stop);
2098                         }
2099                         break;
2100             }
2101         }
2102         else
2103         { // delete the gradient from the object. set fill to unset  FIXME: set to fill of unselected node?
2104             SPCSSAttr *css = sp_repr_css_attr_new ();
2105
2106             // stopinfo->spstop is the selected stop
2107             Inkscape::XML::Node *unselectedrepr = SP_OBJECT_REPR(stopinfo->vector)->firstChild();
2108             if (unselectedrepr == SP_OBJECT_REPR(stopinfo->spstop) ) {
2109                 unselectedrepr = unselectedrepr->next();
2110             }
2111
2112             if (unselectedrepr == NULL) {
2113                 if (stopinfo->draggable->fill_or_stroke) {
2114                     sp_repr_css_unset_property (css, "fill");
2115                 } else {
2116                     sp_repr_css_unset_property (css, "stroke");
2117                 }
2118             } else {
2119                 SPCSSAttr *stopcss = sp_repr_css_attr(unselectedrepr, "style");
2120                 if (stopinfo->draggable->fill_or_stroke) {
2121                     sp_repr_css_set_property(css, "fill", sp_repr_css_property(stopcss, "stop-color", "inkscape:unset"));
2122                     sp_repr_css_set_property(css, "fill-opacity", sp_repr_css_property(stopcss, "stop-opacity", "1"));
2123                 } else {
2124                     sp_repr_css_set_property(css, "stroke", sp_repr_css_property(stopcss, "stop-color", "inkscape:unset"));
2125                     sp_repr_css_set_property(css, "stroke-opacity", sp_repr_css_property(stopcss, "stop-opacity", "1"));
2126                 }
2127                 sp_repr_css_attr_unref (stopcss);
2128             }
2129
2130             sp_repr_css_change (SP_OBJECT_REPR (stopinfo->draggable->item), css, "style");
2131             sp_repr_css_attr_unref (css);
2132         }
2133
2134         endstoplist = g_slist_remove(endstoplist, stopinfo);
2135         delete stopinfo;
2136     }
2137
2138     if (document) {
2139         sp_document_done ( document, SP_VERB_CONTEXT_GRADIENT, _("Delete gradient stop(s)") );
2140     }
2141 }
2142
2143
2144 /*
2145   Local Variables:
2146   mode:c++
2147   c-file-style:"stroustrup"
2148   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
2149   indent-tabs-mode:nil
2150   fill-column:99
2151   End:
2152 */
2153 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :