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