Code

Patch to fix build on Natty by Alex Valavanis
[inkscape.git] / src / eraser-context.cpp
1 /*
2  * Eraser drawing mode
3  *
4  * Authors:
5  *   Mitsuru Oka <oka326@parkcity.ne.jp>
6  *   Lauris Kaplinski <lauris@kaplinski.com>
7  *   bulia byak <buliabyak@users.sf.net>
8  *   MenTaLguY <mental@rydia.net>
9  *   Jon A. Cruz <jon@joncruz.org>
10  *
11  * The original dynadraw code:
12  *   Paul Haeberli <paul@sgi.com>
13  *
14  * Copyright (C) 1998 The Free Software Foundation
15  * Copyright (C) 1999-2005 authors
16  * Copyright (C) 2001-2002 Ximian, Inc.
17  * Copyright (C) 2005-2007 bulia byak
18  * Copyright (C) 2006 MenTaLguY
19  * Copyright (C) 2008 Jon A. Cruz
20  *
21  * Released under GNU GPL, read the file 'COPYING' for more information
22  */
24 #define noERASER_VERBOSE
26 #include "config.h"
28 #include <gtk/gtk.h>
29 #include <gdk/gdkkeysyms.h>
30 #include <glibmm/i18n.h>
31 #include <string>
32 #include <cstring>
33 #include <numeric>
35 #include "svg/svg.h"
36 #include "display/canvas-bpath.h"
37 #include <2geom/bezier-utils.h>
39 #include <glib/gmem.h>
40 #include "macros.h"
41 #include "document.h"
42 #include "selection.h"
43 #include "desktop.h"
44 #include "desktop-events.h"
45 #include "desktop-handles.h"
46 #include "desktop-style.h"
47 #include "message-context.h"
48 #include "preferences.h"
49 #include "pixmaps/cursor-eraser.xpm"
50 #include "xml/repr.h"
51 #include "context-fns.h"
52 #include "sp-item.h"
53 #include "color.h"
54 #include "rubberband.h"
55 #include "splivarot.h"
56 #include "sp-item-group.h"
57 #include "sp-shape.h"
58 #include "sp-path.h"
59 #include "sp-text.h"
60 #include "display/canvas-bpath.h"
61 #include "display/canvas-arena.h"
62 #include "livarot/Shape.h"
63 #include <2geom/isnan.h>
64 #include <2geom/pathvector.h>
66 #include "eraser-context.h"
68 #define ERC_RED_RGBA 0xff0000ff
70 #define TOLERANCE_ERASER 0.1
72 #define ERASER_EPSILON 0.5e-6
73 #define ERASER_EPSILON_START 0.5e-2
74 #define ERASER_VEL_START 1e-5
76 #define DRAG_MIN 0.0
77 #define DRAG_DEFAULT 1.0
78 #define DRAG_MAX 1.0
81 static void sp_eraser_context_class_init(SPEraserContextClass *klass);
82 static void sp_eraser_context_init(SPEraserContext *erc);
83 static void sp_eraser_context_dispose(GObject *object);
85 static void sp_eraser_context_setup(SPEventContext *ec);
86 static void sp_eraser_context_set(SPEventContext *ec, Inkscape::Preferences::Entry *val);
87 static gint sp_eraser_context_root_handler(SPEventContext *ec, GdkEvent *event);
89 static void clear_current(SPEraserContext *dc);
90 static void set_to_accumulated(SPEraserContext *dc);
91 static void add_cap(SPCurve *curve, Geom::Point const &pre, Geom::Point const &from, Geom::Point const &to, Geom::Point const &post, double rounding);
92 static void accumulate_eraser(SPEraserContext *dc);
94 static void fit_and_split(SPEraserContext *erc, gboolean release);
96 static void sp_eraser_reset(SPEraserContext *erc, Geom::Point p);
97 static Geom::Point sp_eraser_get_npoint(SPEraserContext const *erc, Geom::Point v);
98 static Geom::Point sp_eraser_get_vpoint(SPEraserContext const *erc, Geom::Point n);
99 static void draw_temporary_box(SPEraserContext *dc);
102 static SPEventContextClass *eraser_parent_class = 0;
104 GType sp_eraser_context_get_type(void)
106     static GType type = 0;
107     if (!type) {
108         GTypeInfo info = {
109             sizeof(SPEraserContextClass),
110             0, // base_init
111             0, // base_finalize
112             (GClassInitFunc)sp_eraser_context_class_init,
113             0, // class_finalize
114             0, // class_data
115             sizeof(SPEraserContext),
116             0, // n_preallocs
117             (GInstanceInitFunc)sp_eraser_context_init,
118             0 // value_table
119         };
120         type = g_type_register_static(SP_TYPE_COMMON_CONTEXT, "SPEraserContext", &info, static_cast<GTypeFlags>(0));
121     }
122     return type;
125 static void
126 sp_eraser_context_class_init(SPEraserContextClass *klass)
128     GObjectClass *object_class = (GObjectClass *) klass;
129     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
131     eraser_parent_class = (SPEventContextClass*)g_type_class_peek_parent(klass);
133     object_class->dispose = sp_eraser_context_dispose;
135     event_context_class->setup = sp_eraser_context_setup;
136     event_context_class->set = sp_eraser_context_set;
137     event_context_class->root_handler = sp_eraser_context_root_handler;
140 static void
141 sp_eraser_context_init(SPEraserContext *erc)
143     erc->cursor_shape = cursor_eraser_xpm;
144     erc->hot_x = 4;
145     erc->hot_y = 4;
148 static void
149 sp_eraser_context_dispose(GObject *object)
151     //SPEraserContext *erc = SP_ERASER_CONTEXT(object);
153     G_OBJECT_CLASS(eraser_parent_class)->dispose(object);
156 static void
157 sp_eraser_context_setup(SPEventContext *ec)
159     SPEraserContext *erc = SP_ERASER_CONTEXT(ec);
160     SPDesktop *desktop = ec->desktop;
162     if (((SPEventContextClass *) eraser_parent_class)->setup)
163         ((SPEventContextClass *) eraser_parent_class)->setup(ec);
165     erc->accumulated = new SPCurve();
166     erc->currentcurve = new SPCurve();
168     erc->cal1 = new SPCurve();
169     erc->cal2 = new SPCurve();
171     erc->currentshape = sp_canvas_item_new(sp_desktop_sketch(desktop), SP_TYPE_CANVAS_BPATH, NULL);
172     sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(erc->currentshape), ERC_RED_RGBA, SP_WIND_RULE_EVENODD);
173     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(erc->currentshape), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
174     /* fixme: Cannot we cascade it to root more clearly? */
175     g_signal_connect(G_OBJECT(erc->currentshape), "event", G_CALLBACK(sp_desktop_root_handler), desktop);
177 /*
178 static ProfileFloatElement f_profile[PROFILE_FLOAT_SIZE] = {
179     {"mass",0.02, 0.0, 1.0},
180     {"wiggle",0.0, 0.0, 1.0},
181     {"angle",30.0, -90.0, 90.0},
182     {"thinning",0.1, -1.0, 1.0},
183     {"tremor",0.0, 0.0, 1.0},
184     {"flatness",0.9, 0.0, 1.0},
185     {"cap_rounding",0.0, 0.0, 5.0}
186 };
187 */
189     sp_event_context_read(ec, "mass");
190     sp_event_context_read(ec, "wiggle");
191     sp_event_context_read(ec, "angle");
192     sp_event_context_read(ec, "width");
193     sp_event_context_read(ec, "thinning");
194     sp_event_context_read(ec, "tremor");
195     sp_event_context_read(ec, "flatness");
196     sp_event_context_read(ec, "tracebackground");
197     sp_event_context_read(ec, "usepressure");
198     sp_event_context_read(ec, "usetilt");
199     sp_event_context_read(ec, "abs_width");
200     sp_event_context_read(ec, "cap_rounding");
202     erc->is_drawing = false;
204     erc->_message_context = new Inkscape::MessageContext(desktop->messageStack());
206     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
207     if (prefs->getBool("/tools/eraser/selcue", 0) != 0) {
208         ec->enableSelectionCue();
209     }
210 // TODO temp force:
211     ec->enableSelectionCue();
215 static void
216 sp_eraser_context_set(SPEventContext *ec, Inkscape::Preferences::Entry *val)
218     //pass on up to parent class to handle common attributes.
219     if ( eraser_parent_class->set ) {
220         eraser_parent_class->set(ec, val);
221     }
224 static double
225 flerp(double f0, double f1, double p)
227     return f0 + ( f1 - f0 ) * p;
230 /* Get normalized point */
231 static Geom::Point
232 sp_eraser_get_npoint(SPEraserContext const *dc, Geom::Point v)
234     Geom::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
235     double const max = MAX ( drect.dimensions()[Geom::X], drect.dimensions()[Geom::Y] );
236     return Geom::Point(( v[Geom::X] - drect.min()[Geom::X] ) / max,  ( v[Geom::Y] - drect.min()[Geom::Y] ) / max);
239 /* Get view point */
240 static Geom::Point
241 sp_eraser_get_vpoint(SPEraserContext const *dc, Geom::Point n)
243     Geom::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
244     double const max = MAX ( drect.dimensions()[Geom::X], drect.dimensions()[Geom::Y] );
245     return Geom::Point(n[Geom::X] * max + drect.min()[Geom::X], n[Geom::Y] * max + drect.min()[Geom::Y]);
248 static void
249 sp_eraser_reset(SPEraserContext *dc, Geom::Point p)
251     dc->last = dc->cur = sp_eraser_get_npoint(dc, p);
252     dc->vel = Geom::Point(0,0);
253     dc->vel_max = 0;
254     dc->acc = Geom::Point(0,0);
255     dc->ang = Geom::Point(0,0);
256     dc->del = Geom::Point(0,0);
259 static void
260 sp_eraser_extinput(SPEraserContext *dc, GdkEvent *event)
262     if (gdk_event_get_axis (event, GDK_AXIS_PRESSURE, &dc->pressure))
263         dc->pressure = CLAMP (dc->pressure, ERC_MIN_PRESSURE, ERC_MAX_PRESSURE);
264     else
265         dc->pressure = ERC_DEFAULT_PRESSURE;
267     if (gdk_event_get_axis (event, GDK_AXIS_XTILT, &dc->xtilt))
268         dc->xtilt = CLAMP (dc->xtilt, ERC_MIN_TILT, ERC_MAX_TILT);
269     else
270         dc->xtilt = ERC_DEFAULT_TILT;
272     if (gdk_event_get_axis (event, GDK_AXIS_YTILT, &dc->ytilt))
273         dc->ytilt = CLAMP (dc->ytilt, ERC_MIN_TILT, ERC_MAX_TILT);
274     else
275         dc->ytilt = ERC_DEFAULT_TILT;
279 static gboolean
280 sp_eraser_apply(SPEraserContext *dc, Geom::Point p)
282     Geom::Point n = sp_eraser_get_npoint(dc, p);
284     /* Calculate mass and drag */
285     double const mass = flerp(1.0, 160.0, dc->mass);
286     double const drag = flerp(0.0, 0.5, dc->drag * dc->drag);
288     /* Calculate force and acceleration */
289     Geom::Point force = n - dc->cur;
291     // If force is below the absolute threshold ERASER_EPSILON,
292     // or we haven't yet reached ERASER_VEL_START (i.e. at the beginning of stroke)
293     // _and_ the force is below the (higher) ERASER_EPSILON_START threshold,
294     // discard this move. 
295     // This prevents flips, blobs, and jerks caused by microscopic tremor of the tablet pen,
296     // especially bothersome at the start of the stroke where we don't yet have the inertia to
297     // smooth them out.
298     if ( Geom::L2(force) < ERASER_EPSILON || (dc->vel_max < ERASER_VEL_START && Geom::L2(force) < ERASER_EPSILON_START)) {
299         return FALSE;
300     }
302     dc->acc = force / mass;
304     /* Calculate new velocity */
305     dc->vel += dc->acc;
307     if (Geom::L2(dc->vel) > dc->vel_max)
308         dc->vel_max = Geom::L2(dc->vel);
310     /* Calculate angle of drawing tool */
312     double a1;
313     if (dc->usetilt) {
314         // 1a. calculate nib angle from input device tilt:
315         gdouble length = std::sqrt(dc->xtilt*dc->xtilt + dc->ytilt*dc->ytilt);;
317         if (length > 0) {
318             Geom::Point ang1 = Geom::Point(dc->ytilt/length, dc->xtilt/length);
319             a1 = atan2(ang1);
320         }
321         else
322             a1 = 0.0;
323     }
324     else {
325         // 1b. fixed dc->angle (absolutely flat nib):
326         double const radians = ( (dc->angle - 90) / 180.0 ) * M_PI;
327         Geom::Point ang1 = Geom::Point(-sin(radians),  cos(radians));
328         a1 = atan2(ang1);
329     }
331     // 2. perpendicular to dc->vel (absolutely non-flat nib):
332     gdouble const mag_vel = Geom::L2(dc->vel);
333     if ( mag_vel < ERASER_EPSILON ) {
334         return FALSE;
335     }
336     Geom::Point ang2 = Geom::rot90(dc->vel) / mag_vel;
338     // 3. Average them using flatness parameter:
339     // calculate angles
340     double a2 = atan2(ang2);
341     // flip a2 to force it to be in the same half-circle as a1
342     bool flipped = false;
343     if (fabs (a2-a1) > 0.5*M_PI) {
344         a2 += M_PI;
345         flipped = true;
346     }
347     // normalize a2
348     if (a2 > M_PI)
349         a2 -= 2*M_PI;
350     if (a2 < -M_PI)
351         a2 += 2*M_PI;
352     // find the flatness-weighted bisector angle, unflip if a2 was flipped
353     // FIXME: when dc->vel is oscillating around the fixed angle, the new_ang flips back and forth. How to avoid this?
354     double new_ang = a1 + (1 - dc->flatness) * (a2 - a1) - (flipped? M_PI : 0);
356     // Try to detect a sudden flip when the new angle differs too much from the previous for the
357     // current velocity; in that case discard this move
358     double angle_delta = Geom::L2(Geom::Point (cos (new_ang), sin (new_ang)) - dc->ang);
359     if ( angle_delta / Geom::L2(dc->vel) > 4000 ) {
360         return FALSE;
361     }
363     // convert to point
364     dc->ang = Geom::Point (cos (new_ang), sin (new_ang));
366 //    g_print ("force %g  acc %g  vel_max %g  vel %g  a1 %g  a2 %g  new_ang %g\n", Geom::L2(force), Geom::L2(dc->acc), dc->vel_max, Geom::L2(dc->vel), a1, a2, new_ang);
368     /* Apply drag */
369     dc->vel *= 1.0 - drag;
371     /* Update position */
372     dc->last = dc->cur;
373     dc->cur += dc->vel;
375     return TRUE;
378 static void
379 sp_eraser_brush(SPEraserContext *dc)
381     g_assert( dc->npoints >= 0 && dc->npoints < SAMPLING_SIZE );
383     // How much velocity thins strokestyle
384     double vel_thin = flerp (0, 160, dc->vel_thin);
386     // Influence of pressure on thickness
387     double pressure_thick = (dc->usepressure ? dc->pressure : 1.0);
389     // get the real brush point, not the same as pointer (affected by hatch tracking and/or mass
390     // drag)
391     Geom::Point brush = sp_eraser_get_vpoint(dc, dc->cur);
392     Geom::Point brush_w = SP_EVENT_CONTEXT(dc)->desktop->d2w(brush); 
394     double trace_thick = 1;
396     double width = (pressure_thick * trace_thick - vel_thin * Geom::L2(dc->vel)) * dc->width;
398     double tremble_left = 0, tremble_right = 0;
399     if (dc->tremor > 0) {
400         // obtain two normally distributed random variables, using polar Box-Muller transform
401         double x1, x2, w, y1, y2;
402         do {
403             x1 = 2.0 * g_random_double_range(0,1) - 1.0;
404             x2 = 2.0 * g_random_double_range(0,1) - 1.0;
405             w = x1 * x1 + x2 * x2;
406         } while ( w >= 1.0 );
407         w = sqrt( (-2.0 * log( w ) ) / w );
408         y1 = x1 * w;
409         y2 = x2 * w;
411         // deflect both left and right edges randomly and independently, so that:
412         // (1) dc->tremor=1 corresponds to sigma=1, decreasing dc->tremor narrows the bell curve;
413         // (2) deflection depends on width, but is upped for small widths for better visual uniformity across widths;
414         // (3) deflection somewhat depends on speed, to prevent fast strokes looking
415         // comparatively smooth and slow ones excessively jittery
416         tremble_left  = (y1)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*Geom::L2(dc->vel));
417         tremble_right = (y2)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*Geom::L2(dc->vel));
418     }
420     if ( width < 0.02 * dc->width ) {
421         width = 0.02 * dc->width;
422     }
424     double dezoomify_factor = 0.05 * 1000;
425     if (!dc->abs_width) {
426         dezoomify_factor /= SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
427     }
429     Geom::Point del_left = dezoomify_factor * (width + tremble_left) * dc->ang;
430     Geom::Point del_right = dezoomify_factor * (width + tremble_right) * dc->ang;
432     dc->point1[dc->npoints] = brush + del_left;
433     dc->point2[dc->npoints] = brush - del_right;
435     dc->del = 0.5*(del_left + del_right);
437     dc->npoints++;
440 void
441 sp_erc_update_toolbox (SPDesktop *desktop, const gchar *id, double value)
443     desktop->setToolboxAdjustmentValue (id, value);
446 static void
447 eraser_cancel(SPEraserContext *dc)
449     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
450     dc->dragging = FALSE;
451     dc->is_drawing = false;
452     sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), 0);
453             /* Remove all temporary line segments */
454             while (dc->segments) {
455                 gtk_object_destroy(GTK_OBJECT(dc->segments->data));
456                 dc->segments = g_slist_remove(dc->segments, dc->segments->data);
457             }
458             /* reset accumulated curve */
459             dc->accumulated->reset();
460             clear_current(dc);
461             if (dc->repr) {
462                 dc->repr = NULL;
463             }
467 gint
468 sp_eraser_context_root_handler(SPEventContext *event_context,
469                                   GdkEvent *event)
471     SPEraserContext *dc = SP_ERASER_CONTEXT(event_context);
472     SPDesktop *desktop = event_context->desktop;
474     gint ret = FALSE;
476     switch (event->type) {
477         case GDK_BUTTON_PRESS:
478             if (event->button.button == 1 && !event_context->space_panning) {
480                 if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
481                     return TRUE;
482                 }
484                 Geom::Point const button_w(event->button.x,
485                                          event->button.y);
486                 Geom::Point const button_dt(desktop->w2d(button_w));
487                 sp_eraser_reset(dc, button_dt);
488                 sp_eraser_extinput(dc, event);
489                 sp_eraser_apply(dc, button_dt);
490                 dc->accumulated->reset();
491                 if (dc->repr) {
492                     dc->repr = NULL;
493                 }
495                 Inkscape::Rubberband::get(desktop)->start(desktop, button_dt);
496                 Inkscape::Rubberband::get(desktop)->setMode(RUBBERBAND_MODE_TOUCHPATH);
498                 /* initialize first point */
499                 dc->npoints = 0;
501                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
502                                     ( GDK_KEY_PRESS_MASK |
503                                       GDK_BUTTON_RELEASE_MASK |
504                                       GDK_POINTER_MOTION_MASK |
505                                       GDK_BUTTON_PRESS_MASK ),
506                                     NULL,
507                                     event->button.time);
509                 ret = TRUE;
511                 sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 3);
512                 dc->is_drawing = true;
513             }
514             break;
515         case GDK_MOTION_NOTIFY:
516         {
517             Geom::Point const motion_w(event->motion.x,
518                                      event->motion.y);
519             Geom::Point motion_dt(desktop->w2d(motion_w));
520             sp_eraser_extinput(dc, event);
522             dc->_message_context->clear();
524             if ( dc->is_drawing && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {
525                 dc->dragging = TRUE;
527                 dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drawing</b> an eraser stroke"));
529                 if (!sp_eraser_apply(dc, motion_dt)) {
530                     ret = TRUE;
531                     break;
532                 }
534                 if ( dc->cur != dc->last ) {
535                     sp_eraser_brush(dc);
536                     g_assert( dc->npoints > 0 );
537                     fit_and_split(dc, FALSE);
538                 }
539                 ret = TRUE;
540             }
541             Inkscape::Rubberband::get(desktop)->move(motion_dt);
542         }
543         break;
546     case GDK_BUTTON_RELEASE:
547     {
548         Geom::Point const motion_w(event->button.x, event->button.y);
549         Geom::Point const motion_dt(desktop->w2d(motion_w));
551         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
552         sp_canvas_end_forced_full_redraws(desktop->canvas);
553         dc->is_drawing = false;
555         if (dc->dragging && event->button.button == 1 && !event_context->space_panning) {
556             dc->dragging = FALSE;
558             sp_eraser_apply(dc, motion_dt);
560             /* Remove all temporary line segments */
561             while (dc->segments) {
562                 gtk_object_destroy(GTK_OBJECT(dc->segments->data));
563                 dc->segments = g_slist_remove(dc->segments, dc->segments->data);
564             }
566             /* Create object */
567             fit_and_split(dc, TRUE);
568             accumulate_eraser(dc);
569             set_to_accumulated(dc); // performs document_done
571             /* reset accumulated curve */
572             dc->accumulated->reset();
574             clear_current(dc);
575             if (dc->repr) {
576                 dc->repr = NULL;
577             }
579             Inkscape::Rubberband::get(desktop)->stop();
580             dc->_message_context->clear();
581             ret = TRUE;
582         }
583         break;
584     }
586     case GDK_KEY_PRESS:
587         switch (get_group0_keyval (&event->key)) {
588         case GDK_Up:
589         case GDK_KP_Up:
590             if (!MOD__CTRL_ONLY) {
591                 dc->angle += 5.0;
592                 if (dc->angle > 90.0)
593                     dc->angle = 90.0;
594                 sp_erc_update_toolbox (desktop, "eraser-angle", dc->angle);
595                 ret = TRUE;
596             }
597             break;
598         case GDK_Down:
599         case GDK_KP_Down:
600             if (!MOD__CTRL_ONLY) {
601                 dc->angle -= 5.0;
602                 if (dc->angle < -90.0)
603                     dc->angle = -90.0;
604                 sp_erc_update_toolbox (desktop, "eraser-angle", dc->angle);
605                 ret = TRUE;
606             }
607             break;
608         case GDK_Right:
609         case GDK_KP_Right:
610             if (!MOD__CTRL_ONLY) {
611                 dc->width += 0.01;
612                 if (dc->width > 1.0)
613                     dc->width = 1.0;
614                 sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100); // the same spinbutton is for alt+x
615                 ret = TRUE;
616             }
617             break;
618         case GDK_Left:
619         case GDK_KP_Left:
620             if (!MOD__CTRL_ONLY) {
621                 dc->width -= 0.01;
622                 if (dc->width < 0.01)
623                     dc->width = 0.01;
624                 sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
625                 ret = TRUE;
626             }
627             break;
628         case GDK_Home:
629         case GDK_KP_Home:
630             dc->width = 0.01;
631             sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
632             ret = TRUE;
633             break;
634         case GDK_End:
635         case GDK_KP_End:
636             dc->width = 1.0;
637             sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
638             ret = TRUE;
639             break;
640         case GDK_x:
641         case GDK_X:
642             if (MOD__ALT_ONLY) {
643                 desktop->setToolboxFocusTo ("altx-eraser");
644                 ret = TRUE;
645             }
646             break;
647         case GDK_Escape:
648             Inkscape::Rubberband::get(desktop)->stop();
649             if (dc->is_drawing) {
650                 // if drawing, cancel, otherwise pass it up for deselecting
651                 eraser_cancel (dc);
652                 ret = TRUE;
653             }
654             break;
655         case GDK_z:
656         case GDK_Z:
657             if (MOD__CTRL_ONLY && dc->is_drawing) {
658                 // if drawing, cancel, otherwise pass it up for undo
659                 eraser_cancel (dc);
660                 ret = TRUE;
661             }
662             break;
663         default:
664             break;
665         }
666         break;
668     case GDK_KEY_RELEASE:
669         switch (get_group0_keyval(&event->key)) {
670             case GDK_Control_L:
671             case GDK_Control_R:
672                 dc->_message_context->clear();
673                 break;
674             default:
675                 break;
676         }
678     default:
679         break;
680     }
682     if (!ret) {
683         if (((SPEventContextClass *) eraser_parent_class)->root_handler) {
684             ret = ((SPEventContextClass *) eraser_parent_class)->root_handler(event_context, event);
685         }
686     }
688     return ret;
692 static void
693 clear_current(SPEraserContext *dc)
695     // reset bpath
696     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), NULL);
698     // reset curve
699     dc->currentcurve->reset();
700     dc->cal1->reset();
701     dc->cal2->reset();
703     // reset points
704     dc->npoints = 0;
707 static void
708 set_to_accumulated(SPEraserContext *dc)
710     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
711     bool workDone = false;
713     if (!dc->accumulated->is_empty()) {
714         if (!dc->repr) {
715             /* Create object */
716             Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
717             Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
719             /* Set style */
720             sp_desktop_apply_style_tool (desktop, repr, "/tools/eraser", false);
722             dc->repr = repr;
724             SPItem *item=SP_ITEM(desktop->currentLayer()->appendChildRepr(dc->repr));
725             Inkscape::GC::release(dc->repr);
726             item->transform = sp_item_i2doc_affine(SP_ITEM(desktop->currentLayer())).inverse();
727             item->updateRepr();
728         }
729         Geom::PathVector pathv = dc->accumulated->get_pathvector() * desktop->dt2doc();
730         gchar *str = sp_svg_write_path(pathv);
731         g_assert( str != NULL );
732         dc->repr->setAttribute("d", str);
733         g_free(str);
735         if ( dc->repr ) {
736             bool wasSelection = false;
737             Inkscape::Selection *selection = sp_desktop_selection(desktop);
738             Inkscape::Preferences *prefs = Inkscape::Preferences::get();
739             
740             gint eraserMode = prefs->getBool("/tools/eraser/mode") ? 1 : 0;
741             Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
743             SPItem* acid = SP_ITEM(desktop->doc()->getObjectByRepr(dc->repr));
744             Geom::OptRect eraserBbox = acid->getBounds(Geom::identity());
745             Geom::Rect bounds = (*eraserBbox) * desktop->doc2dt();
746             std::vector<SPItem*> remainingItems;
747             GSList* toWorkOn = 0;
748             if (selection->isEmpty()) {
749                 if ( eraserMode ) {
750                     toWorkOn = sp_document_partial_items_in_box(sp_desktop_document(desktop), desktop->dkey, bounds);
751                 } else {
752                     Inkscape::Rubberband *r = Inkscape::Rubberband::get(desktop);
753                     toWorkOn = sp_document_items_at_points(sp_desktop_document(desktop), desktop->dkey, r->getPoints());
754                 }
755                 toWorkOn = g_slist_remove( toWorkOn, acid );
756             } else {
757                 toWorkOn = g_slist_copy(const_cast<GSList*>(selection->itemList()));
758                 wasSelection = true;
759             }
761             if ( g_slist_length(toWorkOn) > 0 ) {
762                 if ( eraserMode ) {
763                     for (GSList *i = toWorkOn ; i ; i = i->next ) {
764                         SPItem *item = SP_ITEM(i->data);
765                         if ( eraserMode ) {
766                             Geom::OptRect bbox = item->getBounds(Geom::identity());
767                             if (bbox && bbox->intersects(*eraserBbox)) {
768                                 Inkscape::XML::Node* dup = dc->repr->duplicate(xml_doc);
769                                 dc->repr->parent()->appendChild(dup);
770                                 Inkscape::GC::release(dup); // parent takes over
772                                 selection->set(item);
773                                 selection->add(dup);
774                                 sp_selected_path_diff_skip_undo(desktop);
775                                 workDone = true; // TODO set this only if something was cut.
776                                 if ( !selection->isEmpty() ) {
777                                     // If the item was not completely erased, track the new remainder.
778                                     GSList *nowSel = g_slist_copy(const_cast<GSList *>(selection->itemList()));
779                                     for (GSList const *i2 = nowSel ; i2 ; i2 = i2->next ) {
780                                         remainingItems.push_back(SP_ITEM(i2->data));
781                                     }
782                                     g_slist_free(nowSel);
783                                 }
784                             } else {
785                                 remainingItems.push_back(item);
786                             }
787                         }
788                     }
789                 } else {
790                     for (GSList *i = toWorkOn ; i ; i = i->next ) {
791                         sp_object_ref( SP_ITEM(i->data), 0 );
792                     }
793                     for (GSList *i = toWorkOn ; i ; i = i->next ) {
794                         SPItem *item = SP_ITEM(i->data);
795                         item->deleteObject(true);
796                         sp_object_unref(item);
797                         workDone = true;
798                     }
799                 }
801                 g_slist_free(toWorkOn);
803                 if ( !eraserMode ) {
804                     //sp_selection_delete(desktop);
805                     remainingItems.clear();
806                 }
808                 selection->clear();
809                 if ( wasSelection ) {
810                     if ( !remainingItems.empty() ) {
811                         selection->add(remainingItems.begin(), remainingItems.end());
812                     }
813                 }
814             }
816             // Remove the eraser stroke itself:
817             sp_repr_unparent( dc->repr );
818             dc->repr = 0;
819         }
820     } else {
821         if (dc->repr) {
822             sp_repr_unparent(dc->repr);
823             dc->repr = 0;
824         }
825     }
828     if ( workDone ) {
829         sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ERASER, 
830                          _("Draw eraser stroke"));
831     } else {
832         sp_document_cancel(sp_desktop_document(desktop));
833     }
836 static void
837 add_cap(SPCurve *curve,
838         Geom::Point const &pre, Geom::Point const &from,
839         Geom::Point const &to, Geom::Point const &post,
840         double rounding)
842     Geom::Point vel = rounding * Geom::rot90( to - from ) / sqrt(2.0);
843     double mag = Geom::L2(vel);
845     Geom::Point v_in = from - pre;
846     double mag_in = Geom::L2(v_in);
847     if ( mag_in > ERASER_EPSILON ) {
848         v_in = mag * v_in / mag_in;
849     } else {
850         v_in = Geom::Point(0, 0);
851     }
853     Geom::Point v_out = to - post;
854     double mag_out = Geom::L2(v_out);
855     if ( mag_out > ERASER_EPSILON ) {
856         v_out = mag * v_out / mag_out;
857     } else {
858         v_out = Geom::Point(0, 0);
859     }
861     if ( Geom::L2(v_in) > ERASER_EPSILON || Geom::L2(v_out) > ERASER_EPSILON ) {
862         curve->curveto(from + v_in, to + v_out, to);
863     }
866 static void
867 accumulate_eraser(SPEraserContext *dc)
869     if ( !dc->cal1->is_empty() && !dc->cal2->is_empty() ) {
870         dc->accumulated->reset(); /*  Is this required ?? */
871         SPCurve *rev_cal2 = dc->cal2->create_reverse();
873         g_assert(dc->cal1->get_segment_count() > 0);
874         g_assert(rev_cal2->get_segment_count() > 0);
875         g_assert( ! dc->cal1->first_path()->closed() );
876         g_assert( ! rev_cal2->first_path()->closed() );
878         Geom::CubicBezier const * dc_cal1_firstseg  = dynamic_cast<Geom::CubicBezier const *>( dc->cal1->first_segment() );
879         Geom::CubicBezier const * rev_cal2_firstseg = dynamic_cast<Geom::CubicBezier const *>( rev_cal2->first_segment() );
880         Geom::CubicBezier const * dc_cal1_lastseg   = dynamic_cast<Geom::CubicBezier const *>( dc->cal1->last_segment() );
881         Geom::CubicBezier const * rev_cal2_lastseg  = dynamic_cast<Geom::CubicBezier const *>( rev_cal2->last_segment() );
882         g_assert( dc_cal1_firstseg );
883         g_assert( rev_cal2_firstseg );
884         g_assert( dc_cal1_lastseg );
885         g_assert( rev_cal2_lastseg );
887         dc->accumulated->append(dc->cal1, FALSE);
889         add_cap(dc->accumulated, (*dc_cal1_lastseg)[2], (*dc_cal1_lastseg)[3], (*rev_cal2_firstseg)[0], (*rev_cal2_firstseg)[1], dc->cap_rounding);
891         dc->accumulated->append(rev_cal2, TRUE);
893         add_cap(dc->accumulated, (*rev_cal2_lastseg)[2], (*rev_cal2_lastseg)[3], (*dc_cal1_firstseg)[0], (*dc_cal1_firstseg)[1], dc->cap_rounding);
895         dc->accumulated->closepath();
897         rev_cal2->unref();
899         dc->cal1->reset();
900         dc->cal2->reset();
901     }
904 static double square(double const x)
906     return x * x;
909 static void
910 fit_and_split(SPEraserContext *dc, gboolean release)
912     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
914     double const tolerance_sq = square( desktop->w2d().descrim() * TOLERANCE_ERASER );
916 #ifdef ERASER_VERBOSE
917     g_print("[F&S:R=%c]", release?'T':'F');
918 #endif
920     if (!( dc->npoints > 0 && dc->npoints < SAMPLING_SIZE ))
921         return; // just clicked
923     if ( dc->npoints == SAMPLING_SIZE - 1 || release ) {
924 #define BEZIER_SIZE       4
925 #define BEZIER_MAX_BEZIERS  8
926 #define BEZIER_MAX_LENGTH ( BEZIER_SIZE * BEZIER_MAX_BEZIERS )
928 #ifdef ERASER_VERBOSE
929         g_print("[F&S:#] dc->npoints:%d, release:%s\n",
930                 dc->npoints, release ? "TRUE" : "FALSE");
931 #endif
933         /* Current eraser */
934         if ( dc->cal1->is_empty() || dc->cal2->is_empty() ) {
935             /* dc->npoints > 0 */
936             /* g_print("erasers(1|2) reset\n"); */
937             dc->cal1->reset();
938             dc->cal2->reset();
940             dc->cal1->moveto(dc->point1[0]);
941             dc->cal2->moveto(dc->point2[0]);
942         }
944         Geom::Point b1[BEZIER_MAX_LENGTH];
945         gint const nb1 = Geom::bezier_fit_cubic_r(b1, dc->point1, dc->npoints,
946                                                tolerance_sq, BEZIER_MAX_BEZIERS);
947         g_assert( nb1 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b1)) );
949         Geom::Point b2[BEZIER_MAX_LENGTH];
950         gint const nb2 = Geom::bezier_fit_cubic_r(b2, dc->point2, dc->npoints,
951                                                tolerance_sq, BEZIER_MAX_BEZIERS);
952         g_assert( nb2 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b2)) );
954         if ( nb1 != -1 && nb2 != -1 ) {
955             /* Fit and draw and reset state */
956 #ifdef ERASER_VERBOSE
957             g_print("nb1:%d nb2:%d\n", nb1, nb2);
958 #endif
959             /* CanvasShape */
960             if (! release) {
961                 dc->currentcurve->reset();
962                 dc->currentcurve->moveto(b1[0]);
963                 for (Geom::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
964                     dc->currentcurve->curveto(bp1[1],
965                                      bp1[2], bp1[3]);
966                 }
967                 dc->currentcurve->lineto(b2[BEZIER_SIZE*(nb2-1) + 3]);
968                 for (Geom::Point *bp2 = b2 + BEZIER_SIZE * ( nb2 - 1 ); bp2 >= b2; bp2 -= BEZIER_SIZE) {
969                     dc->currentcurve->curveto(bp2[2], bp2[1], bp2[0]);
970                 }
971                 // FIXME: dc->segments is always NULL at this point??
972                 if (!dc->segments) { // first segment
973                     add_cap(dc->currentcurve, b2[1], b2[0], b1[0], b1[1], dc->cap_rounding);
974                 }
975                 dc->currentcurve->closepath();
976                 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
977             }
979             /* Current eraser */
980             for (Geom::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
981                 dc->cal1->curveto(bp1[1], bp1[2], bp1[3]);
982             }
983             for (Geom::Point *bp2 = b2; bp2 < b2 + BEZIER_SIZE * nb2; bp2 += BEZIER_SIZE) {
984                 dc->cal2->curveto(bp2[1], bp2[2], bp2[3]);
985             }
986         } else {
987             /* fixme: ??? */
988 #ifdef ERASER_VERBOSE
989             g_print("[fit_and_split] failed to fit-cubic.\n");
990 #endif
991             draw_temporary_box(dc);
993             for (gint i = 1; i < dc->npoints; i++) {
994                 dc->cal1->lineto(dc->point1[i]);
995             }
996             for (gint i = 1; i < dc->npoints; i++) {
997                 dc->cal2->lineto(dc->point2[i]);
998             }
999         }
1001         /* Fit and draw and copy last point */
1002 #ifdef ERASER_VERBOSE
1003         g_print("[%d]Yup\n", dc->npoints);
1004 #endif
1005         if (!release) {
1006             Inkscape::Preferences *prefs = Inkscape::Preferences::get();
1007             gint eraserMode = prefs->getBool("/tools/eraser/mode") ? 1 : 0;
1008             g_assert(!dc->currentcurve->is_empty());
1010             SPCanvasItem *cbp = sp_canvas_item_new(sp_desktop_sketch(desktop),
1011                                                    SP_TYPE_CANVAS_BPATH,
1012                                                    NULL);
1013             SPCurve *curve = dc->currentcurve->copy();
1014             sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH (cbp), curve);
1015             curve->unref();
1017             guint32 fillColor = sp_desktop_get_color_tool (desktop, "/tools/eraser", true);
1018             //guint32 strokeColor = sp_desktop_get_color_tool (desktop, "/tools/eraser", false);
1019             double opacity = sp_desktop_get_master_opacity_tool (desktop, "/tools/eraser");
1020             double fillOpacity = sp_desktop_get_opacity_tool (desktop, "/tools/eraser", true);
1021             //double strokeOpacity = sp_desktop_get_opacity_tool (desktop, "/tools/eraser", false);
1022             sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(cbp), ((fillColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*fillOpacity)), SP_WIND_RULE_EVENODD);
1023             //on second thougtht don't do stroke yet because we don't have stoke-width yet and because stoke appears between segments while drawing
1024             //sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), ((strokeColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*strokeOpacity)), 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1025             sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1026             /* fixme: Cannot we cascade it to root more clearly? */
1027             g_signal_connect(G_OBJECT(cbp), "event", G_CALLBACK(sp_desktop_root_handler), desktop);
1029             dc->segments = g_slist_prepend(dc->segments, cbp);
1031             if ( !eraserMode ) {
1032                 sp_canvas_item_hide(cbp);
1033                 sp_canvas_item_hide(dc->currentshape);
1034             }
1035         }
1037         dc->point1[0] = dc->point1[dc->npoints - 1];
1038         dc->point2[0] = dc->point2[dc->npoints - 1];
1039         dc->npoints = 1;
1040     } else {
1041         draw_temporary_box(dc);
1042     }
1045 static void
1046 draw_temporary_box(SPEraserContext *dc)
1048     dc->currentcurve->reset();
1050     dc->currentcurve->moveto(dc->point1[dc->npoints-1]);
1051     for (gint i = dc->npoints-2; i >= 0; i--) {
1052         dc->currentcurve->lineto(dc->point1[i]);
1053     }
1054     for (gint i = 0; i < dc->npoints; i++) {
1055         dc->currentcurve->lineto(dc->point2[i]);
1056     }
1057     if (dc->npoints >= 2) {
1058         add_cap(dc->currentcurve, dc->point2[dc->npoints-2], dc->point2[dc->npoints-1], dc->point1[dc->npoints-1], dc->point1[dc->npoints-2], dc->cap_rounding);
1059     }
1061     dc->currentcurve->closepath();
1062     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
1065 /*
1066   Local Variables:
1067   mode:c++
1068   c-file-style:"stroustrup"
1069   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1070   indent-tabs-mode:nil
1071   fill-column:99
1072   End:
1073 */
1074 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :