src/dyna-draw-context.cpp

   1 #define __SP_DYNA_DRAW_CONTEXT_C__
   2
   3 /*
   4  * Handwriting-like drawing mode
   5  *
   6  * Authors:
   7  *   Mitsuru Oka <oka326@parkcity.ne.jp>
   8  *   Lauris Kaplinski <lauris@kaplinski.com>
   9  *   bulia byak <buliabyak@users.sf.net>
  10  *   MenTaLguY <mental@rydia.net>
  11  *
  12  * The original dynadraw code:
  13  *   Paul Haeberli <paul@sgi.com>
  14  *
  15  * Copyright (C) 1998 The Free Software Foundation
  16  * Copyright (C) 1999-2005 authors
  17  * Copyright (C) 2001-2002 Ximian, Inc.
  18  * Copyright (C) 2005-2006 bulia byak
  19  * Copyright (C) 2006 MenTaLguY
  20  *
  21  * Released under GNU GPL, read the file 'COPYING' for more information
  22  */
  23
  24 #define noDYNA_DRAW_VERBOSE
  25
  26 #include "config.h"
  27
  28 #include <gtk/gtk.h>
  29 #include <gdk/gdkkeysyms.h>
  30
  31 #include "svg/svg.h"
  32 #include "display/canvas-bpath.h"
  33 #include "display/bezier-utils.h"
  34
  35 #include <glib/gmem.h>
  36 #include "macros.h"
  37 #include "document.h"
  38 #include "selection.h"
  39 #include "desktop.h"
  40 #include "desktop-events.h"
  41 #include "desktop-handles.h"
  42 #include "desktop-affine.h"
  43 #include "desktop-style.h"
  44 #include "message-context.h"
  45 #include "pixmaps/cursor-calligraphy.xpm"
  46 #include "pixmaps/cursor-calligraphy.pixbuf"
  47 #include "dyna-draw-context.h"
  48 #include "libnr/n-art-bpath.h"
  49 #include "libnr/nr-path.h"
  50 #include "xml/repr.h"
  51 #include "context-fns.h"
  52 #include "sp-item.h"
  53 #include "inkscape.h"
  54 #include "color.h"
  55
  56 #define DDC_RED_RGBA 0xff0000ff
  57
  58 #define SAMPLE_TIMEOUT 10
  59 #define TOLERANCE_LINE 1.0
  60 #define TOLERANCE_CALLIGRAPHIC 3.0
  61 #define DYNA_EPSILON 0.5e-2
  62
  63 #define DYNA_MIN_WIDTH 1.0e-6
  64
  65 #define DRAG_MIN 0.0
  66 #define DRAG_DEFAULT 1.0
  67 #define DRAG_MAX 1.0
  68
  69 static void sp_dyna_draw_context_class_init(SPDynaDrawContextClass *klass);
  70 static void sp_dyna_draw_context_init(SPDynaDrawContext *ddc);
  71 static void sp_dyna_draw_context_dispose(GObject *object);
  72
  73 static void sp_dyna_draw_context_setup(SPEventContext *ec);
  74 static void sp_dyna_draw_context_set(SPEventContext *ec, gchar const *key, gchar const *val);
  75 static gint sp_dyna_draw_context_root_handler(SPEventContext *ec, GdkEvent *event);
  76
  77 static void clear_current(SPDynaDrawContext *dc);
  78 static void set_to_accumulated(SPDynaDrawContext *dc);
  79 static void add_cap(SPCurve *curve, NR::Point const &from, NR::Point const &to, double rounding);
  80 static void accumulate_calligraphic(SPDynaDrawContext *dc);
  81
  82 static void fit_and_split(SPDynaDrawContext *ddc, gboolean release);
  83
  84 static void sp_dyna_draw_reset(SPDynaDrawContext *ddc, NR::Point p);
  85 static NR::Point sp_dyna_draw_get_npoint(SPDynaDrawContext const *ddc, NR::Point v);
  86 static NR::Point sp_dyna_draw_get_vpoint(SPDynaDrawContext const *ddc, NR::Point n);
  87 static void draw_temporary_box(SPDynaDrawContext *dc);
  88
  89
  90 static SPEventContextClass *parent_class;
  91
  92 GtkType
  93 sp_dyna_draw_context_get_type(void)
  94 {
  95     static GType type = 0;
  96     if (!type) {
  97         GTypeInfo info = {
  98             sizeof(SPDynaDrawContextClass),
  99             NULL, NULL,
 100             (GClassInitFunc) sp_dyna_draw_context_class_init,
 101             NULL, NULL,
 102             sizeof(SPDynaDrawContext),
 103             4,
 104             (GInstanceInitFunc) sp_dyna_draw_context_init,
 105             NULL,   /* value_table */
 106         };
 107         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPDynaDrawContext", &info, (GTypeFlags)0);
 108     }
 109     return type;
 110 }
 111
 112 static void
 113 sp_dyna_draw_context_class_init(SPDynaDrawContextClass *klass)
 114 {
 115     GObjectClass *object_class = (GObjectClass *) klass;
 116     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
 117
 118     parent_class = (SPEventContextClass*)g_type_class_peek_parent(klass);
 119
 120     object_class->dispose = sp_dyna_draw_context_dispose;
 121
 122     event_context_class->setup = sp_dyna_draw_context_setup;
 123     event_context_class->set = sp_dyna_draw_context_set;
 124     event_context_class->root_handler = sp_dyna_draw_context_root_handler;
 125 }
 126
 127 static void
 128 sp_dyna_draw_context_init(SPDynaDrawContext *ddc)
 129 {
 130     SPEventContext *event_context = SP_EVENT_CONTEXT(ddc);
 131
 132     event_context->cursor_shape = cursor_calligraphy_xpm;
 133     event_context->cursor_pixbuf = gdk_pixbuf_new_from_inline(
 134             -1,
 135             cursor_calligraphy_pixbuf,
 136             FALSE,
 137             NULL);
 138     event_context->hot_x = 4;
 139     event_context->hot_y = 4;
 140
 141     ddc->accumulated = NULL;
 142     ddc->segments = NULL;
 143     ddc->currentcurve = NULL;
 144     ddc->currentshape = NULL;
 145     ddc->npoints = 0;
 146     ddc->cal1 = NULL;
 147     ddc->cal2 = NULL;
 148     ddc->repr = NULL;
 149
 150     /* DynaDraw values */
 151     ddc->cur = NR::Point(0,0);
 152     ddc->last = NR::Point(0,0);
 153     ddc->vel = NR::Point(0,0);
 154     ddc->acc = NR::Point(0,0);
 155     ddc->ang = NR::Point(0,0);
 156     ddc->del = NR::Point(0,0);
 157
 158     /* attributes */
 159     ddc->dragging = FALSE;
 160
 161     ddc->mass = 0.3;
 162     ddc->drag = DRAG_DEFAULT;
 163     ddc->angle = 30.0;
 164     ddc->width = 0.2;
 165
 166     ddc->vel_thin = 0.1;
 167     ddc->flatness = 0.9;
 168     ddc->cap_rounding = 0.0;
 169
 170     ddc->abs_width = false;
 171     ddc->keep_selected = true;
 172 }
 173
 174 static void
 175 sp_dyna_draw_context_dispose(GObject *object)
 176 {
 177     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(object);
 178
 179     if (ddc->accumulated) {
 180         ddc->accumulated = sp_curve_unref(ddc->accumulated);
 181     }
 182
 183     while (ddc->segments) {
 184         gtk_object_destroy(GTK_OBJECT(ddc->segments->data));
 185         ddc->segments = g_slist_remove(ddc->segments, ddc->segments->data);
 186     }
 187
 188     if (ddc->currentcurve) ddc->currentcurve = sp_curve_unref(ddc->currentcurve);
 189     if (ddc->cal1) ddc->cal1 = sp_curve_unref(ddc->cal1);
 190     if (ddc->cal2) ddc->cal2 = sp_curve_unref(ddc->cal2);
 191
 192     if (ddc->currentshape) {
 193         gtk_object_destroy(GTK_OBJECT(ddc->currentshape));
 194         ddc->currentshape = NULL;
 195     }
 196
 197     if (ddc->_message_context) {
 198         delete ddc->_message_context;
 199     }
 200
 201     G_OBJECT_CLASS(parent_class)->dispose(object);
 202 }
 203
 204 static void
 205 sp_dyna_draw_context_setup(SPEventContext *ec)
 206 {
 207     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(ec);
 208
 209     if (((SPEventContextClass *) parent_class)->setup)
 210         ((SPEventContextClass *) parent_class)->setup(ec);
 211
 212     ddc->accumulated = sp_curve_new_sized(32);
 213     ddc->currentcurve = sp_curve_new_sized(4);
 214
 215     ddc->cal1 = sp_curve_new_sized(32);
 216     ddc->cal2 = sp_curve_new_sized(32);
 217
 218     ddc->currentshape = sp_canvas_item_new(sp_desktop_sketch(ec->desktop), SP_TYPE_CANVAS_BPATH, NULL);
 219     sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(ddc->currentshape), DDC_RED_RGBA, SP_WIND_RULE_EVENODD);
 220     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(ddc->currentshape), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 221     /* fixme: Cannot we cascade it to root more clearly? */
 222     g_signal_connect(G_OBJECT(ddc->currentshape), "event", G_CALLBACK(sp_desktop_root_handler), ec->desktop);
 223
 224     sp_event_context_read(ec, "mass");
 225     sp_event_context_read(ec, "drag");
 226     sp_event_context_read(ec, "angle");
 227     sp_event_context_read(ec, "width");
 228     sp_event_context_read(ec, "thinning");
 229     sp_event_context_read(ec, "tremor");
 230     sp_event_context_read(ec, "flatness");
 231     sp_event_context_read(ec, "usepressure");
 232     sp_event_context_read(ec, "usetilt");
 233     sp_event_context_read(ec, "abs_width");
 234     sp_event_context_read(ec, "keep_selected");
 235     sp_event_context_read(ec, "cap_rounding");
 236
 237     ddc->is_drawing = false;
 238
 239     ddc->_message_context = new Inkscape::MessageContext((ec->desktop)->messageStack());
 240 }
 241
 242 static void
 243 sp_dyna_draw_context_set(SPEventContext *ec, gchar const *key, gchar const *val)
 244 {
 245     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(ec);
 246
 247     if (!strcmp(key, "mass")) {
 248         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.2 );
 249         ddc->mass = CLAMP(dval, -1000.0, 1000.0);
 250     } else if (!strcmp(key, "drag")) {
 251         double const dval = ( val ? g_ascii_strtod (val, NULL) : DRAG_DEFAULT );
 252         ddc->drag = CLAMP(dval, DRAG_MIN, DRAG_MAX);
 253     } else if (!strcmp(key, "angle")) {
 254         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0);
 255         ddc->angle = CLAMP (dval, -90, 90);
 256     } else if (!strcmp(key, "width")) {
 257         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
 258         ddc->width = CLAMP(dval, -1000.0, 1000.0);
 259     } else if (!strcmp(key, "thinning")) {
 260         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
 261         ddc->vel_thin = CLAMP(dval, -1.0, 1.0);
 262     } else if (!strcmp(key, "tremor")) {
 263         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
 264         ddc->tremor = CLAMP(dval, 0.0, 1.0);
 265     } else if (!strcmp(key, "flatness")) {
 266         double const dval = ( val ? g_ascii_strtod (val, NULL) : 1.0 );
 267         ddc->flatness = CLAMP(dval, 0, 1.0);
 268     } else if (!strcmp(key, "usepressure")) {
 269         ddc->usepressure = (val && strcmp(val, "0"));
 270     } else if (!strcmp(key, "usetilt")) {
 271         ddc->usetilt = (val && strcmp(val, "0"));
 272     } else if (!strcmp(key, "abs_width")) {
 273         ddc->abs_width = (val && strcmp(val, "0"));
 274     } else if (!strcmp(key, "keep_selected")) {
 275         ddc->keep_selected = (val && strcmp(val, "0"));
 276     } else if (!strcmp(key, "cap_rounding")) {
 277         ddc->cap_rounding = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
 278     }
 279
 280     //g_print("DDC: %g %g %g %g\n", ddc->mass, ddc->drag, ddc->angle, ddc->width);
 281 }
 282
 283 static double
 284 flerp(double f0, double f1, double p)
 285 {
 286     return f0 + ( f1 - f0 ) * p;
 287 }
 288
 289 /* Get normalized point */
 290 static NR::Point
 291 sp_dyna_draw_get_npoint(SPDynaDrawContext const *dc, NR::Point v)
 292 {
 293     NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
 294     double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
 295     return NR::Point(( v[NR::X] - drect.min()[NR::X] ) / max,  ( v[NR::Y] - drect.min()[NR::Y] ) / max);
 296 }
 297
 298 /* Get view point */
 299 static NR::Point
 300 sp_dyna_draw_get_vpoint(SPDynaDrawContext const *dc, NR::Point n)
 301 {
 302     NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
 303     double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
 304     return NR::Point(n[NR::X] * max + drect.min()[NR::X], n[NR::Y] * max + drect.min()[NR::Y]);
 305 }
 306
 307 static void
 308 sp_dyna_draw_reset(SPDynaDrawContext *dc, NR::Point p)
 309 {
 310     dc->last = dc->cur = sp_dyna_draw_get_npoint(dc, p);
 311     dc->vel = NR::Point(0,0);
 312     dc->acc = NR::Point(0,0);
 313     dc->ang = NR::Point(0,0);
 314     dc->del = NR::Point(0,0);
 315 }
 316
 317 static void
 318 sp_dyna_draw_extinput(SPDynaDrawContext *dc, GdkEvent *event)
 319 {
 320     if (gdk_event_get_axis (event, GDK_AXIS_PRESSURE, &dc->pressure))
 321         dc->pressure = CLAMP (dc->pressure, DDC_MIN_PRESSURE, DDC_MAX_PRESSURE);
 322     else
 323         dc->pressure = DDC_DEFAULT_PRESSURE;
 324
 325     if (gdk_event_get_axis (event, GDK_AXIS_XTILT, &dc->xtilt))
 326         dc->xtilt = CLAMP (dc->xtilt, DDC_MIN_TILT, DDC_MAX_TILT);
 327     else
 328         dc->xtilt = DDC_DEFAULT_TILT;
 329
 330     if (gdk_event_get_axis (event, GDK_AXIS_YTILT, &dc->ytilt))
 331         dc->ytilt = CLAMP (dc->ytilt, DDC_MIN_TILT, DDC_MAX_TILT);
 332     else
 333         dc->ytilt = DDC_DEFAULT_TILT;
 334 }
 335
 336
 337 static gboolean
 338 sp_dyna_draw_apply(SPDynaDrawContext *dc, NR::Point p)
 339 {
 340     NR::Point n = sp_dyna_draw_get_npoint(dc, p);
 341
 342     /* Calculate mass and drag */
 343     double const mass = flerp(1.0, 160.0, dc->mass);
 344     double const drag = flerp(0.0, 0.5, dc->drag * dc->drag);
 345
 346     /* Calculate force and acceleration */
 347     NR::Point force = n - dc->cur;
 348     if ( NR::L2(force) < DYNA_EPSILON ) {
 349         return FALSE;
 350     }
 351
 352     dc->acc = force / mass;
 353
 354     /* Calculate new velocity */
 355     dc->vel += dc->acc;
 356
 357     /* Calculate angle of drawing tool */
 358
 359     double a1;
 360     if (dc->usetilt) {
 361         // 1a. calculate nib angle from input device tilt:
 362         gdouble length = std::sqrt(dc->xtilt*dc->xtilt + dc->ytilt*dc->ytilt);;
 363
 364         if (length > 0) {
 365             NR::Point ang1 = NR::Point(dc->ytilt/length, dc->xtilt/length);
 366             a1 = atan2(ang1);
 367         }
 368         else
 369             a1 = 0.0;
 370     }
 371     else {
 372         // 1b. fixed dc->angle (absolutely flat nib):
 373         double const radians = ( (dc->angle - 90) / 180.0 ) * M_PI;
 374         NR::Point ang1 = NR::Point(-sin(radians),  cos(radians));
 375         a1 = atan2(ang1);
 376     }
 377
 378     // 2. perpendicular to dc->vel (absolutely non-flat nib):
 379     gdouble const mag_vel = NR::L2(dc->vel);
 380     if ( mag_vel < DYNA_EPSILON ) {
 381         return FALSE;
 382     }
 383     NR::Point ang2 = NR::rot90(dc->vel) / mag_vel;
 384
 385     // 3. Average them using flatness parameter:
 386     // calculate angles
 387     double a2 = atan2(ang2);
 388     // flip a2 to force it to be in the same half-circle as a1
 389     bool flipped = false;
 390     if (fabs (a2-a1) > 0.5*M_PI) {
 391         a2 += M_PI;
 392         flipped = true;
 393     }
 394     // normalize a2
 395     if (a2 > M_PI)
 396         a2 -= 2*M_PI;
 397     if (a2 < -M_PI)
 398         a2 += 2*M_PI;
 399     // find the flatness-weighted bisector angle, unflip if a2 was flipped
 400     // FIXME: when dc->vel is oscillating around the fixed angle, the new_ang flips back and forth. How to avoid this?
 401     double new_ang = a1 + (1 - dc->flatness) * (a2 - a1) - (flipped? M_PI : 0);
 402     // convert to point
 403     dc->ang = NR::Point (cos (new_ang), sin (new_ang));
 404
 405     /* Apply drag */
 406     dc->vel *= 1.0 - drag;
 407
 408     /* Update position */
 409     dc->last = dc->cur;
 410     dc->cur += dc->vel;
 411
 412     return TRUE;
 413 }
 414
 415 static void
 416 sp_dyna_draw_brush(SPDynaDrawContext *dc)
 417 {
 418     g_assert( dc->npoints >= 0 && dc->npoints < SAMPLING_SIZE );
 419
 420     // How much velocity thins strokestyle
 421     double vel_thin = flerp (0, 160, dc->vel_thin);
 422
 423     // Influence of pressure on thickness
 424     double pressure_thick = (dc->usepressure ? dc->pressure : 1.0);
 425
 426     double width = ( pressure_thick - vel_thin * NR::L2(dc->vel) ) * dc->width;
 427
 428     double tremble_left = 0, tremble_right = 0;
 429     if (dc->tremor > 0) {
 430         // obtain two normally distributed random variables, using polar Box-Muller transform
 431         double x1, x2, w, y1, y2;
 432         do {
 433             x1 = 2.0 * g_random_double_range(0,1) - 1.0;
 434             x2 = 2.0 * g_random_double_range(0,1) - 1.0;
 435             w = x1 * x1 + x2 * x2;
 436         } while ( w >= 1.0 );
 437         w = sqrt( (-2.0 * log( w ) ) / w );
 438         y1 = x1 * w;
 439         y2 = x2 * w;
 440
 441         // deflect both left and right edges randomly and independently, so that:
 442         // (1) dc->tremor=1 corresponds to sigma=1, decreasing dc->tremor narrows the bell curve;
 443         // (2) deflection depends on width, but is upped for small widths for better visual uniformity across widths;
 444         // (3) deflection somewhat depends on speed, to prevent fast strokes looking
 445         // comparatively smooth and slow ones excessively jittery
 446         tremble_left  = (y1)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
 447         tremble_right = (y2)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
 448     }
 449
 450     if ( width < 0.02 * dc->width ) {
 451         width = 0.02 * dc->width;
 452     }
 453
 454     double dezoomify_factor = 0.05 * 1000;
 455     if (!dc->abs_width) {
 456         dezoomify_factor /= SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
 457     }
 458
 459     NR::Point del_left = dezoomify_factor * (width + tremble_left) * dc->ang;
 460     NR::Point del_right = dezoomify_factor * (width + tremble_right) * dc->ang;
 461
 462     NR::Point abs_middle = sp_dyna_draw_get_vpoint(dc, dc->cur);
 463
 464     dc->point1[dc->npoints] = abs_middle + del_left;
 465     dc->point2[dc->npoints] = abs_middle - del_right;
 466
 467     dc->del = 0.5*(del_left + del_right);
 468
 469     dc->npoints++;
 470 }
 471
 472 void
 473 sp_ddc_update_toolbox (SPDesktop *desktop, const gchar *id, double value)
 474 {
 475     desktop->setToolboxAdjustmentValue (id, value);
 476 }
 477
 478 gint
 479 sp_dyna_draw_context_root_handler(SPEventContext *event_context,
 480                                   GdkEvent *event)
 481 {
 482     SPDynaDrawContext *dc = SP_DYNA_DRAW_CONTEXT(event_context);
 483     SPDesktop *desktop = event_context->desktop;
 484
 485     gint ret = FALSE;
 486
 487     switch (event->type) {
 488     case GDK_BUTTON_PRESS:
 489         if ( event->button.button == 1 ) {
 490
 491             SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
 492
 493             if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
 494                 return TRUE;
 495             }
 496
 497             NR::Point const button_w(event->button.x,
 498                                      event->button.y);
 499             NR::Point const button_dt(desktop->w2d(button_w));
 500             sp_dyna_draw_reset(dc, button_dt);
 501             sp_dyna_draw_extinput(dc, event);
 502             sp_dyna_draw_apply(dc, button_dt);
 503             sp_curve_reset(dc->accumulated);
 504             if (dc->repr) {
 505                 dc->repr = NULL;
 506             }
 507
 508             /* initialize first point */
 509             dc->npoints = 0;
 510
 511             sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
 512                                 ( GDK_KEY_PRESS_MASK |
 513                                   GDK_BUTTON_RELEASE_MASK |
 514                                   GDK_POINTER_MOTION_MASK |
 515                                   GDK_BUTTON_PRESS_MASK ),
 516                                 NULL,
 517                                 event->button.time);
 518
 519             ret = TRUE;
 520
 521             dc->is_drawing = true;
 522         }
 523         break;
 524     case GDK_MOTION_NOTIFY:
 525         if ( dc->is_drawing && ( event->motion.state & GDK_BUTTON1_MASK ) ) {
 526             dc->dragging = TRUE;
 527
 528             NR::Point const motion_w(event->motion.x,
 529                                      event->motion.y);
 530             NR::Point const motion_dt(desktop->w2d(motion_w));
 531
 532             sp_dyna_draw_extinput(dc, event);
 533             if (!sp_dyna_draw_apply(dc, motion_dt)) {
 534                 ret = TRUE;
 535                 break;
 536             }
 537
 538             if ( dc->cur != dc->last ) {
 539                 sp_dyna_draw_brush(dc);
 540                 g_assert( dc->npoints > 0 );
 541                 fit_and_split(dc, FALSE);
 542             }
 543             ret = TRUE;
 544         }
 545         break;
 546
 547     case GDK_BUTTON_RELEASE:
 548         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
 549         dc->is_drawing = false;
 550
 551         if ( dc->dragging && event->button.button == 1 ) {
 552             dc->dragging = FALSE;
 553
 554             NR::Point const motion_w(event->button.x, event->button.y);
 555             NR::Point const motion_dt(desktop->w2d(motion_w));
 556             sp_dyna_draw_apply(dc, motion_dt);
 557
 558             /* Remove all temporary line segments */
 559             while (dc->segments) {
 560                 gtk_object_destroy(GTK_OBJECT(dc->segments->data));
 561                 dc->segments = g_slist_remove(dc->segments, dc->segments->data);
 562             }
 563             /* Create object */
 564             fit_and_split(dc, TRUE);
 565             accumulate_calligraphic(dc);
 566             set_to_accumulated(dc); /* temporal implementation */
 567             /* reset accumulated curve */
 568             sp_curve_reset(dc->accumulated);
 569             clear_current(dc);
 570             if (dc->repr) {
 571                 dc->repr = NULL;
 572             }
 573             ret = TRUE;
 574         }
 575         break;
 576     case GDK_KEY_PRESS:
 577         switch (get_group0_keyval (&event->key)) {
 578         case GDK_Up:
 579         case GDK_KP_Up:
 580             if (!MOD__CTRL_ONLY) {
 581                 dc->angle += 5.0;
 582                 if (dc->angle > 90.0)
 583                     dc->angle = 90.0;
 584                 sp_ddc_update_toolbox (desktop, "calligraphy-angle", dc->angle);
 585                 ret = TRUE;
 586             }
 587             break;
 588         case GDK_Down:
 589         case GDK_KP_Down:
 590             if (!MOD__CTRL_ONLY) {
 591                 dc->angle -= 5.0;
 592                 if (dc->angle < -90.0)
 593                     dc->angle = -90.0;
 594                 sp_ddc_update_toolbox (desktop, "calligraphy-angle", dc->angle);
 595                 ret = TRUE;
 596             }
 597             break;
 598         case GDK_Right:
 599         case GDK_KP_Right:
 600             if (!MOD__CTRL_ONLY) {
 601                 dc->width += 0.01;
 602                 if (dc->width > 1.0)
 603                     dc->width = 1.0;
 604                 sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100); // the same spinbutton is for alt+x
 605                 ret = TRUE;
 606             }
 607             break;
 608         case GDK_Left:
 609         case GDK_KP_Left:
 610             if (!MOD__CTRL_ONLY) {
 611                 dc->width -= 0.01;
 612                 if (dc->width < 0.01)
 613                     dc->width = 0.01;
 614                 sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100);
 615                 ret = TRUE;
 616             }
 617             break;
 618         case GDK_x:
 619         case GDK_X:
 620             if (MOD__ALT_ONLY) {
 621                 desktop->setToolboxFocusTo ("altx-calligraphy");
 622                 ret = TRUE;
 623             }
 624             break;
 625         case GDK_Escape:
 626             sp_desktop_selection(desktop)->clear();
 627             break;
 628
 629         default:
 630             break;
 631         }
 632     default:
 633         break;
 634     }
 635
 636     if (!ret) {
 637         if (((SPEventContextClass *) parent_class)->root_handler) {
 638             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
 639         }
 640     }
 641
 642     return ret;
 643 }
 644
 645
 646 static void
 647 clear_current(SPDynaDrawContext *dc)
 648 {
 649     /* reset bpath */
 650     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), NULL);
 651     /* reset curve */
 652     sp_curve_reset(dc->currentcurve);
 653     sp_curve_reset(dc->cal1);
 654     sp_curve_reset(dc->cal2);
 655     /* reset points */
 656     dc->npoints = 0;
 657 }
 658
 659 static void
 660 set_to_accumulated(SPDynaDrawContext *dc)
 661 {
 662     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
 663
 664     if (!sp_curve_empty(dc->accumulated)) {
 665         NArtBpath *abp;
 666         gchar *str;
 667
 668         if (!dc->repr) {
 669             /* Create object */
 670             Inkscape::XML::Node *repr = sp_repr_new("svg:path");
 671
 672             /* Set style */
 673             sp_desktop_apply_style_tool (desktop, repr, "tools.calligraphic", false);
 674
 675             dc->repr = repr;
 676
 677             SPItem *item=SP_ITEM(desktop->currentLayer()->appendChildRepr(dc->repr));
 678             Inkscape::GC::release(dc->repr);
 679             item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
 680             item->updateRepr();
 681             if (dc->keep_selected) {
 682                 sp_desktop_selection(desktop)->set(dc->repr);
 683             } else {
 684                 sp_desktop_selection(desktop)->clear();
 685             }
 686         }
 687         abp = nr_artpath_affine(sp_curve_first_bpath(dc->accumulated), sp_desktop_dt2root_affine(desktop));
 688         str = sp_svg_write_path(abp);
 689         g_assert( str != NULL );
 690         g_free(abp);
 691         dc->repr->setAttribute("d", str);
 692         g_free(str);
 693     } else {
 694         if (dc->repr) {
 695             sp_repr_unparent(dc->repr);
 696         }
 697         dc->repr = NULL;
 698     }
 699
 700     sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_CALLIGRAPHIC,
 701                      /* TODO: annotate */ "dyna-draw-context.cpp:689");
 702 }
 703
 704 static void
 705 add_cap(SPCurve *curve, NR::Point const &from, NR::Point const &to,
 706         double rounding)
 707 {
 708     NR::Point vec = rounding * NR::rot90( ( to - from ) / sqrt(2.0) );
 709
 710     if ( NR::L2(vec) > DYNA_EPSILON ) {
 711         sp_curve_curveto(curve, from + vec, to + vec, to);
 712     }
 713 }
 714
 715 static void
 716 accumulate_calligraphic(SPDynaDrawContext *dc)
 717 {
 718     if ( !sp_curve_empty(dc->cal1) && !sp_curve_empty(dc->cal2) ) {
 719         sp_curve_reset(dc->accumulated); /*  Is this required ?? */
 720         SPCurve *rev_cal2 = sp_curve_reverse(dc->cal2);
 721         sp_curve_append(dc->accumulated, dc->cal1, FALSE);
 722         add_cap(dc->accumulated, sp_curve_last_point(dc->cal1), sp_curve_first_point(rev_cal2), dc->cap_rounding);
 723         sp_curve_append(dc->accumulated, rev_cal2, TRUE);
 724         add_cap(dc->accumulated, sp_curve_last_point(rev_cal2), sp_curve_first_point(dc->cal1), dc->cap_rounding);
 725         sp_curve_closepath(dc->accumulated);
 726
 727         sp_curve_unref(rev_cal2);
 728
 729         sp_curve_reset(dc->cal1);
 730         sp_curve_reset(dc->cal2);
 731     }
 732 }
 733
 734 static double square(double const x)
 735 {
 736     return x * x;
 737 }
 738
 739 static void
 740 fit_and_split(SPDynaDrawContext *dc, gboolean release)
 741 {
 742     double const tolerance_sq = square( NR::expansion(SP_EVENT_CONTEXT(dc)->desktop->w2d()) * TOLERANCE_CALLIGRAPHIC );
 743
 744 #ifdef DYNA_DRAW_VERBOSE
 745     g_print("[F&S:R=%c]", release?'T':'F');
 746 #endif
 747
 748     if (!( dc->npoints > 0 && dc->npoints < SAMPLING_SIZE ))
 749         return; // just clicked
 750
 751     if ( dc->npoints == SAMPLING_SIZE - 1 || release ) {
 752 #define BEZIER_SIZE       4
 753 #define BEZIER_MAX_BEZIERS  8
 754 #define BEZIER_MAX_LENGTH ( BEZIER_SIZE * BEZIER_MAX_BEZIERS )
 755
 756 #ifdef DYNA_DRAW_VERBOSE
 757         g_print("[F&S:#] dc->npoints:%d, release:%s\n",
 758                 dc->npoints, release ? "TRUE" : "FALSE");
 759 #endif
 760
 761         /* Current calligraphic */
 762         if ( dc->cal1->end == 0 || dc->cal2->end == 0 ) {
 763             /* dc->npoints > 0 */
 764             /* g_print("calligraphics(1|2) reset\n"); */
 765             sp_curve_reset(dc->cal1);
 766             sp_curve_reset(dc->cal2);
 767
 768             sp_curve_moveto(dc->cal1, dc->point1[0]);
 769             sp_curve_moveto(dc->cal2, dc->point2[0]);
 770         }
 771
 772         NR::Point b1[BEZIER_MAX_LENGTH];
 773         gint const nb1 = sp_bezier_fit_cubic_r(b1, dc->point1, dc->npoints,
 774                                                tolerance_sq, BEZIER_MAX_BEZIERS);
 775         g_assert( nb1 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b1)) );
 776
 777         NR::Point b2[BEZIER_MAX_LENGTH];
 778         gint const nb2 = sp_bezier_fit_cubic_r(b2, dc->point2, dc->npoints,
 779                                                tolerance_sq, BEZIER_MAX_BEZIERS);
 780         g_assert( nb2 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b2)) );
 781
 782         if ( nb1 != -1 && nb2 != -1 ) {
 783             /* Fit and draw and reset state */
 784 #ifdef DYNA_DRAW_VERBOSE
 785             g_print("nb1:%d nb2:%d\n", nb1, nb2);
 786 #endif
 787             /* CanvasShape */
 788             if (! release) {
 789                 sp_curve_reset(dc->currentcurve);
 790                 sp_curve_moveto(dc->currentcurve, b1[0]);
 791                 for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
 792                     sp_curve_curveto(dc->currentcurve, bp1[1],
 793                                      bp1[2], bp1[3]);
 794                 }
 795                 sp_curve_lineto(dc->currentcurve,
 796                                 b2[BEZIER_SIZE*(nb2-1) + 3]);
 797                 for (NR::Point *bp2 = b2 + BEZIER_SIZE * ( nb2 - 1 ); bp2 >= b2; bp2 -= BEZIER_SIZE) {
 798                     sp_curve_curveto(dc->currentcurve, bp2[2], bp2[1], bp2[0]);
 799                 }
 800                 if (!dc->segments) {
 801                     add_cap(dc->currentcurve, b2[0], b1[0], dc->cap_rounding);
 802                 }
 803                 sp_curve_closepath(dc->currentcurve);
 804                 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
 805             }
 806
 807             /* Current calligraphic */
 808             for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
 809                 sp_curve_curveto(dc->cal1, bp1[1], bp1[2], bp1[3]);
 810             }
 811             for (NR::Point *bp2 = b2; bp2 < b2 + BEZIER_SIZE * nb2; bp2 += BEZIER_SIZE) {
 812                 sp_curve_curveto(dc->cal2, bp2[1], bp2[2], bp2[3]);
 813             }
 814         } else {
 815             /* fixme: ??? */
 816 #ifdef DYNA_DRAW_VERBOSE
 817             g_print("[fit_and_split] failed to fit-cubic.\n");
 818 #endif
 819             draw_temporary_box(dc);
 820
 821             for (gint i = 1; i < dc->npoints; i++) {
 822                 sp_curve_lineto(dc->cal1, dc->point1[i]);
 823             }
 824             for (gint i = 1; i < dc->npoints; i++) {
 825                 sp_curve_lineto(dc->cal2, dc->point2[i]);
 826             }
 827         }
 828
 829         /* Fit and draw and copy last point */
 830 #ifdef DYNA_DRAW_VERBOSE
 831         g_print("[%d]Yup\n", dc->npoints);
 832 #endif
 833         if (!release) {
 834             g_assert(!sp_curve_empty(dc->currentcurve));
 835
 836             SPCanvasItem *cbp = sp_canvas_item_new(sp_desktop_sketch(SP_EVENT_CONTEXT(dc)->desktop),
 837                                                    SP_TYPE_CANVAS_BPATH,
 838                                                    NULL);
 839             SPCurve *curve = sp_curve_copy(dc->currentcurve);
 840             sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH (cbp), curve);
 841             sp_curve_unref(curve);
 842
 843             guint32 fillColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", true);
 844             //guint32 strokeColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", false);
 845             double opacity = sp_desktop_get_master_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic");
 846             double fillOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", true);
 847             //double strokeOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", false);
 848             sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(cbp), ((fillColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*fillOpacity)), SP_WIND_RULE_EVENODD);
 849             //on second thougtht don't do stroke yet because we don't have stoke-width yet and because stoke appears between segments while drawing
 850             //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);
 851             sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 852             /* fixme: Cannot we cascade it to root more clearly? */
 853             g_signal_connect(G_OBJECT(cbp), "event", G_CALLBACK(sp_desktop_root_handler), SP_EVENT_CONTEXT(dc)->desktop);
 854
 855             dc->segments = g_slist_prepend(dc->segments, cbp);
 856         }
 857
 858         dc->point1[0] = dc->point1[dc->npoints - 1];
 859         dc->point2[0] = dc->point2[dc->npoints - 1];
 860         dc->npoints = 1;
 861     } else {
 862         draw_temporary_box(dc);
 863     }
 864 }
 865
 866 static void
 867 draw_temporary_box(SPDynaDrawContext *dc)
 868 {
 869     sp_curve_reset(dc->currentcurve);
 870     sp_curve_moveto(dc->currentcurve, dc->point1[0]);
 871     for (gint i = 1; i < dc->npoints; i++) {
 872         sp_curve_lineto(dc->currentcurve, dc->point1[i]);
 873     }
 874     for (gint i = dc->npoints-1; i >= 0; i--) {
 875         sp_curve_lineto(dc->currentcurve, dc->point2[i]);
 876     }
 877     add_cap(dc->currentcurve, dc->point2[0], dc->point1[0], dc->cap_rounding);
 878     sp_curve_closepath(dc->currentcurve);
 879     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
 880 }
 881
 882 /*
 883   Local Variables:
 884   mode:c++
 885   c-file-style:"stroustrup"
 886   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 887   indent-tabs-mode:nil
 888   fill-column:99
 889   End:
 890 */
 891 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :