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) 2005-2007 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 #include <glibmm/i18n.h>
  31
  32 #include <numeric>
  33
  34 #include "svg/svg.h"
  35 #include "display/canvas-bpath.h"
  36 #include "display/bezier-utils.h"
  37
  38 #include <glib/gmem.h>
  39 #include "macros.h"
  40 #include "document.h"
  41 #include "selection.h"
  42 #include "desktop.h"
  43 #include "desktop-events.h"
  44 #include "desktop-handles.h"
  45 #include "desktop-affine.h"
  46 #include "desktop-style.h"
  47 #include "message-context.h"
  48 #include "pixmaps/cursor-calligraphy.xpm"
  49 #include "pixmaps/cursor-thin.xpm"
  50 #include "pixmaps/cursor-thicken.xpm"
  51 #include "libnr/n-art-bpath.h"
  52 #include "libnr/nr-path.h"
  53 #include "libnr/nr-matrix-ops.h"
  54 #include "libnr/nr-scale-translate-ops.h"
  55 #include "xml/repr.h"
  56 #include "context-fns.h"
  57 #include "sp-item.h"
  58 #include "inkscape.h"
  59 #include "color.h"
  60 #include "splivarot.h"
  61 #include "sp-shape.h"
  62 #include "sp-path.h"
  63 #include "sp-text.h"
  64 #include "display/canvas-bpath.h"
  65 #include "display/canvas-arena.h"
  66 #include "livarot/Shape.h"
  67 #include "isnan.h"
  68
  69 #include "dyna-draw-context.h"
  70
  71 #define DDC_RED_RGBA 0xff0000ff
  72
  73 #define TOLERANCE_CALLIGRAPHIC 0.1
  74
  75 #define DYNA_EPSILON 0.5e-6
  76 #define DYNA_EPSILON_START 0.5e-2
  77 #define DYNA_VEL_START 1e-5
  78
  79 #define DYNA_MIN_WIDTH 1.0e-6
  80
  81 #define DRAG_MIN 0.0
  82 #define DRAG_DEFAULT 1.0
  83 #define DRAG_MAX 1.0
  84
  85 // FIXME: move it to some shared file to be reused by both calligraphy and dropper
  86 #define C1 0.552
  87 static NArtBpath const hatch_area_circle[] = {
  88     { NR_MOVETO, 0, 0, 0, 0, -1, 0 },
  89     { NR_CURVETO, -1, C1, -C1, 1, 0, 1 },
  90     { NR_CURVETO, C1, 1, 1, C1, 1, 0 },
  91     { NR_CURVETO, 1, -C1, C1, -1, 0, -1 },
  92     { NR_CURVETO, -C1, -1, -1, -C1, -1, 0 },
  93     { NR_END, 0, 0, 0, 0, 0, 0 }
  94 };
  95 #undef C1
  96
  97
  98 static void sp_dyna_draw_context_class_init(SPDynaDrawContextClass *klass);
  99 static void sp_dyna_draw_context_init(SPDynaDrawContext *ddc);
 100 static void sp_dyna_draw_context_dispose(GObject *object);
 101
 102 static void sp_dyna_draw_context_setup(SPEventContext *ec);
 103 static void sp_dyna_draw_context_set(SPEventContext *ec, gchar const *key, gchar const *val);
 104 static gint sp_dyna_draw_context_root_handler(SPEventContext *ec, GdkEvent *event);
 105
 106 static void clear_current(SPDynaDrawContext *dc);
 107 static void set_to_accumulated(SPDynaDrawContext *dc, bool unionize);
 108 static void add_cap(SPCurve *curve, NR::Point const &pre, NR::Point const &from, NR::Point const &to, NR::Point const &post, double rounding);
 109 static void accumulate_calligraphic(SPDynaDrawContext *dc);
 110
 111 static void fit_and_split(SPDynaDrawContext *ddc, gboolean release);
 112
 113 static void sp_dyna_draw_reset(SPDynaDrawContext *ddc, NR::Point p);
 114 static NR::Point sp_dyna_draw_get_npoint(SPDynaDrawContext const *ddc, NR::Point v);
 115 static NR::Point sp_dyna_draw_get_vpoint(SPDynaDrawContext const *ddc, NR::Point n);
 116 static void draw_temporary_box(SPDynaDrawContext *dc);
 117
 118
 119 static SPEventContextClass *parent_class;
 120
 121 GtkType
 122 sp_dyna_draw_context_get_type(void)
 123 {
 124     static GType type = 0;
 125     if (!type) {
 126         GTypeInfo info = {
 127             sizeof(SPDynaDrawContextClass),
 128             NULL, NULL,
 129             (GClassInitFunc) sp_dyna_draw_context_class_init,
 130             NULL, NULL,
 131             sizeof(SPDynaDrawContext),
 132             4,
 133             (GInstanceInitFunc) sp_dyna_draw_context_init,
 134             NULL,   /* value_table */
 135         };
 136         type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPDynaDrawContext", &info, (GTypeFlags)0);
 137     }
 138     return type;
 139 }
 140
 141 static void
 142 sp_dyna_draw_context_class_init(SPDynaDrawContextClass *klass)
 143 {
 144     GObjectClass *object_class = (GObjectClass *) klass;
 145     SPEventContextClass *event_context_class = (SPEventContextClass *) klass;
 146
 147     parent_class = (SPEventContextClass*)g_type_class_peek_parent(klass);
 148
 149     object_class->dispose = sp_dyna_draw_context_dispose;
 150
 151     event_context_class->setup = sp_dyna_draw_context_setup;
 152     event_context_class->set = sp_dyna_draw_context_set;
 153     event_context_class->root_handler = sp_dyna_draw_context_root_handler;
 154 }
 155
 156 static void
 157 sp_dyna_draw_context_init(SPDynaDrawContext *ddc)
 158 {
 159     SPEventContext *event_context = SP_EVENT_CONTEXT(ddc);
 160
 161     event_context->cursor_shape = cursor_calligraphy_xpm;
 162     event_context->hot_x = 4;
 163     event_context->hot_y = 4;
 164
 165     ddc->accumulated = NULL;
 166     ddc->segments = NULL;
 167     ddc->currentcurve = NULL;
 168     ddc->currentshape = NULL;
 169     ddc->npoints = 0;
 170     ddc->cal1 = NULL;
 171     ddc->cal2 = NULL;
 172     ddc->repr = NULL;
 173
 174     /* DynaDraw values */
 175     ddc->cur = NR::Point(0,0);
 176     ddc->last = NR::Point(0,0);
 177     ddc->vel = NR::Point(0,0);
 178     ddc->vel_max = 0;
 179     ddc->acc = NR::Point(0,0);
 180     ddc->ang = NR::Point(0,0);
 181     ddc->del = NR::Point(0,0);
 182
 183     /* attributes */
 184     ddc->dragging = FALSE;
 185
 186     ddc->mass = 0.3;
 187     ddc->drag = DRAG_DEFAULT;
 188     ddc->angle = 30.0;
 189     ddc->width = 0.2;
 190     ddc->pressure = DDC_DEFAULT_PRESSURE;
 191
 192     ddc->vel_thin = 0.1;
 193     ddc->flatness = 0.9;
 194     ddc->cap_rounding = 0.0;
 195
 196     ddc->abs_width = false;
 197     ddc->keep_selected = true;
 198
 199     ddc->hatch_spacing = 0;
 200     new (&ddc->hatch_pointer_past) std::list<double>();
 201     new (&ddc->hatch_nearest_past) std::list<double>();
 202     ddc->hatch_last_nearest = NR::Point(0,0);
 203     ddc->hatch_last_pointer = NR::Point(0,0);
 204     ddc->hatch_vector_accumulated = NR::Point(0,0);
 205     ddc->hatch_escaped = false;
 206     ddc->hatch_area = NULL;
 207     ddc->hatch_item = NULL;
 208     ddc->hatch_livarot_path = NULL;
 209
 210     ddc->trace_bg = false;
 211
 212     ddc->is_dilating = false;
 213 }
 214
 215 static void
 216 sp_dyna_draw_context_dispose(GObject *object)
 217 {
 218     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(object);
 219
 220     if (ddc->hatch_area) {
 221         gtk_object_destroy(GTK_OBJECT(ddc->hatch_area));
 222         ddc->hatch_area = NULL;
 223     }
 224
 225     if (ddc->dilate_area) {
 226         gtk_object_destroy(GTK_OBJECT(ddc->dilate_area));
 227         ddc->dilate_area = NULL;
 228     }
 229
 230     if (ddc->accumulated) {
 231         ddc->accumulated = sp_curve_unref(ddc->accumulated);
 232     }
 233
 234     while (ddc->segments) {
 235         gtk_object_destroy(GTK_OBJECT(ddc->segments->data));
 236         ddc->segments = g_slist_remove(ddc->segments, ddc->segments->data);
 237     }
 238
 239     if (ddc->currentcurve) ddc->currentcurve = sp_curve_unref(ddc->currentcurve);
 240     if (ddc->cal1) ddc->cal1 = sp_curve_unref(ddc->cal1);
 241     if (ddc->cal2) ddc->cal2 = sp_curve_unref(ddc->cal2);
 242
 243     if (ddc->currentshape) {
 244         gtk_object_destroy(GTK_OBJECT(ddc->currentshape));
 245         ddc->currentshape = NULL;
 246     }
 247
 248     if (ddc->_message_context) {
 249         delete ddc->_message_context;
 250     }
 251
 252     G_OBJECT_CLASS(parent_class)->dispose(object);
 253
 254     ddc->hatch_pointer_past.~list();
 255     ddc->hatch_nearest_past.~list();
 256 }
 257
 258 static void
 259 sp_dyna_draw_context_setup(SPEventContext *ec)
 260 {
 261     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(ec);
 262
 263     if (((SPEventContextClass *) parent_class)->setup)
 264         ((SPEventContextClass *) parent_class)->setup(ec);
 265
 266     ddc->accumulated = sp_curve_new_sized(32);
 267     ddc->currentcurve = sp_curve_new_sized(4);
 268
 269     ddc->cal1 = sp_curve_new_sized(32);
 270     ddc->cal2 = sp_curve_new_sized(32);
 271
 272     ddc->currentshape = sp_canvas_item_new(sp_desktop_sketch(ec->desktop), SP_TYPE_CANVAS_BPATH, NULL);
 273     sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(ddc->currentshape), DDC_RED_RGBA, SP_WIND_RULE_EVENODD);
 274     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(ddc->currentshape), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 275     /* fixme: Cannot we cascade it to root more clearly? */
 276     g_signal_connect(G_OBJECT(ddc->currentshape), "event", G_CALLBACK(sp_desktop_root_handler), ec->desktop);
 277
 278     {
 279         SPCurve *c = sp_curve_new_from_foreign_bpath(hatch_area_circle);
 280         ddc->hatch_area = sp_canvas_bpath_new(sp_desktop_controls(ec->desktop), c);
 281         sp_curve_unref(c);
 282         sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(ddc->hatch_area), 0x00000000,(SPWindRule)0);
 283         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(ddc->hatch_area), 0x0000007f, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 284         sp_canvas_item_hide(ddc->hatch_area);
 285     }
 286
 287     {
 288         SPCurve *c = sp_curve_new_from_foreign_bpath(hatch_area_circle);
 289         ddc->dilate_area = sp_canvas_bpath_new(sp_desktop_controls(ec->desktop), c);
 290         sp_curve_unref(c);
 291         sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(ddc->dilate_area), 0x00000000,(SPWindRule)0);
 292         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(ddc->dilate_area), 0xff9900ff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 293         sp_canvas_item_hide(ddc->dilate_area);
 294     }
 295
 296     sp_event_context_read(ec, "mass");
 297     sp_event_context_read(ec, "wiggle");
 298     sp_event_context_read(ec, "angle");
 299     sp_event_context_read(ec, "width");
 300     sp_event_context_read(ec, "thinning");
 301     sp_event_context_read(ec, "tremor");
 302     sp_event_context_read(ec, "flatness");
 303     sp_event_context_read(ec, "tracebackground");
 304     sp_event_context_read(ec, "usepressure");
 305     sp_event_context_read(ec, "usetilt");
 306     sp_event_context_read(ec, "abs_width");
 307     sp_event_context_read(ec, "keep_selected");
 308     sp_event_context_read(ec, "cap_rounding");
 309
 310     ddc->is_drawing = false;
 311
 312     ddc->_message_context = new Inkscape::MessageContext((ec->desktop)->messageStack());
 313 }
 314
 315 static void
 316 sp_dyna_draw_context_set(SPEventContext *ec, gchar const *key, gchar const *val)
 317 {
 318     SPDynaDrawContext *ddc = SP_DYNA_DRAW_CONTEXT(ec);
 319
 320     if (!strcmp(key, "mass")) {
 321         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.2 );
 322         ddc->mass = CLAMP(dval, -1000.0, 1000.0);
 323     } else if (!strcmp(key, "wiggle")) {
 324         double const dval = ( val ? g_ascii_strtod (val, NULL) : (1 - DRAG_DEFAULT));
 325         ddc->drag = CLAMP((1 - dval), DRAG_MIN, DRAG_MAX); // drag is inverse to wiggle
 326     } else if (!strcmp(key, "angle")) {
 327         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0);
 328         ddc->angle = CLAMP (dval, -90, 90);
 329     } else if (!strcmp(key, "width")) {
 330         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
 331         ddc->width = CLAMP(dval, -1000.0, 1000.0);
 332     } else if (!strcmp(key, "thinning")) {
 333         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
 334         ddc->vel_thin = CLAMP(dval, -1.0, 1.0);
 335     } else if (!strcmp(key, "tremor")) {
 336         double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
 337         ddc->tremor = CLAMP(dval, 0.0, 1.0);
 338     } else if (!strcmp(key, "flatness")) {
 339         double const dval = ( val ? g_ascii_strtod (val, NULL) : 1.0 );
 340         ddc->flatness = CLAMP(dval, 0, 1.0);
 341     } else if (!strcmp(key, "tracebackground")) {
 342         ddc->trace_bg = (val && strcmp(val, "0"));
 343     } else if (!strcmp(key, "usepressure")) {
 344         ddc->usepressure = (val && strcmp(val, "0"));
 345     } else if (!strcmp(key, "usetilt")) {
 346         ddc->usetilt = (val && strcmp(val, "0"));
 347     } else if (!strcmp(key, "abs_width")) {
 348         ddc->abs_width = (val && strcmp(val, "0"));
 349     } else if (!strcmp(key, "keep_selected")) {
 350         ddc->keep_selected = (val && strcmp(val, "0"));
 351     } else if (!strcmp(key, "cap_rounding")) {
 352         ddc->cap_rounding = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
 353     }
 354
 355     //g_print("DDC: %g %g %g %g\n", ddc->mass, ddc->drag, ddc->angle, ddc->width);
 356 }
 357
 358 static double
 359 flerp(double f0, double f1, double p)
 360 {
 361     return f0 + ( f1 - f0 ) * p;
 362 }
 363
 364 /* Get normalized point */
 365 static NR::Point
 366 sp_dyna_draw_get_npoint(SPDynaDrawContext const *dc, NR::Point v)
 367 {
 368     NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
 369     double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
 370     return NR::Point(( v[NR::X] - drect.min()[NR::X] ) / max,  ( v[NR::Y] - drect.min()[NR::Y] ) / max);
 371 }
 372
 373 /* Get view point */
 374 static NR::Point
 375 sp_dyna_draw_get_vpoint(SPDynaDrawContext const *dc, NR::Point n)
 376 {
 377     NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
 378     double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
 379     return NR::Point(n[NR::X] * max + drect.min()[NR::X], n[NR::Y] * max + drect.min()[NR::Y]);
 380 }
 381
 382 static void
 383 sp_dyna_draw_reset(SPDynaDrawContext *dc, NR::Point p)
 384 {
 385     dc->last = dc->cur = sp_dyna_draw_get_npoint(dc, p);
 386     dc->vel = NR::Point(0,0);
 387     dc->vel_max = 0;
 388     dc->acc = NR::Point(0,0);
 389     dc->ang = NR::Point(0,0);
 390     dc->del = NR::Point(0,0);
 391 }
 392
 393 static void
 394 sp_dyna_draw_extinput(SPDynaDrawContext *dc, GdkEvent *event)
 395 {
 396     if (gdk_event_get_axis (event, GDK_AXIS_PRESSURE, &dc->pressure))
 397         dc->pressure = CLAMP (dc->pressure, DDC_MIN_PRESSURE, DDC_MAX_PRESSURE);
 398     else
 399         dc->pressure = DDC_DEFAULT_PRESSURE;
 400
 401     if (gdk_event_get_axis (event, GDK_AXIS_XTILT, &dc->xtilt))
 402         dc->xtilt = CLAMP (dc->xtilt, DDC_MIN_TILT, DDC_MAX_TILT);
 403     else
 404         dc->xtilt = DDC_DEFAULT_TILT;
 405
 406     if (gdk_event_get_axis (event, GDK_AXIS_YTILT, &dc->ytilt))
 407         dc->ytilt = CLAMP (dc->ytilt, DDC_MIN_TILT, DDC_MAX_TILT);
 408     else
 409         dc->ytilt = DDC_DEFAULT_TILT;
 410 }
 411
 412
 413 static gboolean
 414 sp_dyna_draw_apply(SPDynaDrawContext *dc, NR::Point p)
 415 {
 416     NR::Point n = sp_dyna_draw_get_npoint(dc, p);
 417
 418     /* Calculate mass and drag */
 419     double const mass = flerp(1.0, 160.0, dc->mass);
 420     double const drag = flerp(0.0, 0.5, dc->drag * dc->drag);
 421
 422     /* Calculate force and acceleration */
 423     NR::Point force = n - dc->cur;
 424
 425     // If force is below the absolute threshold DYNA_EPSILON,
 426     // or we haven't yet reached DYNA_VEL_START (i.e. at the beginning of stroke)
 427     // _and_ the force is below the (higher) DYNA_EPSILON_START threshold,
 428     // discard this move.
 429     // This prevents flips, blobs, and jerks caused by microscopic tremor of the tablet pen,
 430     // especially bothersome at the start of the stroke where we don't yet have the inertia to
 431     // smooth them out.
 432     if ( NR::L2(force) < DYNA_EPSILON || (dc->vel_max < DYNA_VEL_START && NR::L2(force) < DYNA_EPSILON_START)) {
 433         return FALSE;
 434     }
 435
 436     dc->acc = force / mass;
 437
 438     /* Calculate new velocity */
 439     dc->vel += dc->acc;
 440
 441     if (NR::L2(dc->vel) > dc->vel_max)
 442         dc->vel_max = NR::L2(dc->vel);
 443
 444     /* Calculate angle of drawing tool */
 445
 446     double a1;
 447     if (dc->usetilt) {
 448         // 1a. calculate nib angle from input device tilt:
 449         gdouble length = std::sqrt(dc->xtilt*dc->xtilt + dc->ytilt*dc->ytilt);;
 450
 451         if (length > 0) {
 452             NR::Point ang1 = NR::Point(dc->ytilt/length, dc->xtilt/length);
 453             a1 = atan2(ang1);
 454         }
 455         else
 456             a1 = 0.0;
 457     }
 458     else {
 459         // 1b. fixed dc->angle (absolutely flat nib):
 460         double const radians = ( (dc->angle - 90) / 180.0 ) * M_PI;
 461         NR::Point ang1 = NR::Point(-sin(radians),  cos(radians));
 462         a1 = atan2(ang1);
 463     }
 464
 465     // 2. perpendicular to dc->vel (absolutely non-flat nib):
 466     gdouble const mag_vel = NR::L2(dc->vel);
 467     if ( mag_vel < DYNA_EPSILON ) {
 468         return FALSE;
 469     }
 470     NR::Point ang2 = NR::rot90(dc->vel) / mag_vel;
 471
 472     // 3. Average them using flatness parameter:
 473     // calculate angles
 474     double a2 = atan2(ang2);
 475     // flip a2 to force it to be in the same half-circle as a1
 476     bool flipped = false;
 477     if (fabs (a2-a1) > 0.5*M_PI) {
 478         a2 += M_PI;
 479         flipped = true;
 480     }
 481     // normalize a2
 482     if (a2 > M_PI)
 483         a2 -= 2*M_PI;
 484     if (a2 < -M_PI)
 485         a2 += 2*M_PI;
 486     // find the flatness-weighted bisector angle, unflip if a2 was flipped
 487     // FIXME: when dc->vel is oscillating around the fixed angle, the new_ang flips back and forth. How to avoid this?
 488     double new_ang = a1 + (1 - dc->flatness) * (a2 - a1) - (flipped? M_PI : 0);
 489
 490     // Try to detect a sudden flip when the new angle differs too much from the previous for the
 491     // current velocity; in that case discard this move
 492     double angle_delta = NR::L2(NR::Point (cos (new_ang), sin (new_ang)) - dc->ang);
 493     if ( angle_delta / NR::L2(dc->vel) > 4000 ) {
 494         return FALSE;
 495     }
 496
 497     // convert to point
 498     dc->ang = NR::Point (cos (new_ang), sin (new_ang));
 499
 500 //    g_print ("force %g  acc %g  vel_max %g  vel %g  a1 %g  a2 %g  new_ang %g\n", NR::L2(force), NR::L2(dc->acc), dc->vel_max, NR::L2(dc->vel), a1, a2, new_ang);
 501
 502     /* Apply drag */
 503     dc->vel *= 1.0 - drag;
 504
 505     /* Update position */
 506     dc->last = dc->cur;
 507     dc->cur += dc->vel;
 508
 509     return TRUE;
 510 }
 511
 512 static void
 513 sp_dyna_draw_brush(SPDynaDrawContext *dc)
 514 {
 515     g_assert( dc->npoints >= 0 && dc->npoints < SAMPLING_SIZE );
 516
 517     // How much velocity thins strokestyle
 518     double vel_thin = flerp (0, 160, dc->vel_thin);
 519
 520     // Influence of pressure on thickness
 521     double pressure_thick = (dc->usepressure ? dc->pressure : 1.0);
 522
 523     // get the real brush point, not the same as pointer (affected by hatch tracking and/or mass
 524     // drag)
 525     NR::Point brush = sp_dyna_draw_get_vpoint(dc, dc->cur);
 526     NR::Point brush_w = SP_EVENT_CONTEXT(dc)->desktop->d2w(brush);
 527
 528     double trace_thick = 1;
 529     if (dc->trace_bg) {
 530         // pick single pixel
 531         NRPixBlock pb;
 532         int x = (int) floor(brush_w[NR::X]);
 533         int y = (int) floor(brush_w[NR::Y]);
 534         nr_pixblock_setup_fast(&pb, NR_PIXBLOCK_MODE_R8G8B8A8P, x, y, x+1, y+1, TRUE);
 535         sp_canvas_arena_render_pixblock(SP_CANVAS_ARENA(sp_desktop_drawing(SP_EVENT_CONTEXT(dc)->desktop)), &pb);
 536         const unsigned char *s = NR_PIXBLOCK_PX(&pb);
 537         double R = s[0] / 255.0;
 538         double G = s[1] / 255.0;
 539         double B = s[2] / 255.0;
 540         double A = s[3] / 255.0;
 541         double max = MAX (MAX (R, G), B);
 542         double min = MIN (MIN (R, G), B);
 543         double L = A * (max + min)/2 + (1 - A); // blend with white bg
 544         trace_thick = 1 - L;
 545         //g_print ("L %g thick %g\n", L, trace_thick);
 546     }
 547
 548     double width = (pressure_thick * trace_thick - vel_thin * NR::L2(dc->vel)) * dc->width;
 549
 550     double tremble_left = 0, tremble_right = 0;
 551     if (dc->tremor > 0) {
 552         // obtain two normally distributed random variables, using polar Box-Muller transform
 553         double x1, x2, w, y1, y2;
 554         do {
 555             x1 = 2.0 * g_random_double_range(0,1) - 1.0;
 556             x2 = 2.0 * g_random_double_range(0,1) - 1.0;
 557             w = x1 * x1 + x2 * x2;
 558         } while ( w >= 1.0 );
 559         w = sqrt( (-2.0 * log( w ) ) / w );
 560         y1 = x1 * w;
 561         y2 = x2 * w;
 562
 563         // deflect both left and right edges randomly and independently, so that:
 564         // (1) dc->tremor=1 corresponds to sigma=1, decreasing dc->tremor narrows the bell curve;
 565         // (2) deflection depends on width, but is upped for small widths for better visual uniformity across widths;
 566         // (3) deflection somewhat depends on speed, to prevent fast strokes looking
 567         // comparatively smooth and slow ones excessively jittery
 568         tremble_left  = (y1)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
 569         tremble_right = (y2)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
 570     }
 571
 572     if ( width < 0.02 * dc->width ) {
 573         width = 0.02 * dc->width;
 574     }
 575
 576     double dezoomify_factor = 0.05 * 1000;
 577     if (!dc->abs_width) {
 578         dezoomify_factor /= SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
 579     }
 580
 581     NR::Point del_left = dezoomify_factor * (width + tremble_left) * dc->ang;
 582     NR::Point del_right = dezoomify_factor * (width + tremble_right) * dc->ang;
 583
 584     dc->point1[dc->npoints] = brush + del_left;
 585     dc->point2[dc->npoints] = brush - del_right;
 586
 587     dc->del = 0.5*(del_left + del_right);
 588
 589     dc->npoints++;
 590 }
 591
 592 double
 593 get_dilate_radius (SPDynaDrawContext *dc)
 594 {
 595     // 10 times the pen width:
 596     return 500 * dc->width/SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
 597 }
 598
 599 double
 600 get_dilate_force (SPDynaDrawContext *dc)
 601 {
 602     double force = 4 * dc->pressure/SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
 603     if (force > 3) {
 604         force += 8 * (force - 3);
 605     }
 606     return force;
 607 }
 608
 609 bool
 610 sp_ddc_dilate (SPDynaDrawContext *dc, NR::Point p, bool expand)
 611 {
 612     Inkscape::Selection *selection = sp_desktop_selection(SP_EVENT_CONTEXT(dc)->desktop);
 613
 614     if (selection->isEmpty()) {
 615         return false;
 616     }
 617
 618     bool did = false;
 619     double radius = get_dilate_radius(dc);
 620     double offset = get_dilate_force(dc);
 621     if (radius == 0 || offset == 0) {
 622         return false;
 623     }
 624
 625     for (GSList *items = g_slist_copy((GSList *) selection->itemList());
 626          items != NULL;
 627          items = items->next) {
 628
 629         SPItem *item = (SPItem *) items->data;
 630
 631         // only paths
 632         if (!SP_IS_PATH(item))
 633             continue;
 634
 635         SPCurve *curve = NULL;
 636         curve = sp_shape_get_curve(SP_SHAPE(item));
 637         if (curve == NULL)
 638             continue;
 639
 640         // skip those paths whose bboxes are entirely out of reach with our radius
 641         NR::Maybe<NR::Rect> bbox = item->getBounds(sp_item_i2doc_affine(item));
 642         if (bbox) {
 643             bbox->growBy(radius);
 644             if (!bbox->contains(p)) {
 645                 continue;
 646             }
 647         }
 648
 649         Path *orig = Path_for_item(item, false);
 650         if (orig == NULL) {
 651             sp_curve_unref(curve);
 652             continue;
 653         }
 654         Path *res = new Path;
 655         res->SetBackData(false);
 656
 657         Shape *theShape = new Shape;
 658         Shape *theRes = new Shape;
 659
 660         orig->ConvertWithBackData(0.05);
 661         orig->Fill(theShape, 0);
 662
 663         SPCSSAttr *css = sp_repr_css_attr(SP_OBJECT_REPR(item), "style");
 664         gchar const *val = sp_repr_css_property(css, "fill-rule", NULL);
 665         if (val && strcmp(val, "nonzero") == 0)
 666         {
 667             theRes->ConvertToShape(theShape, fill_nonZero);
 668         }
 669         else if (val && strcmp(val, "evenodd") == 0)
 670         {
 671             theRes->ConvertToShape(theShape, fill_oddEven);
 672         }
 673         else
 674         {
 675             theRes->ConvertToShape(theShape, fill_nonZero);
 676         }
 677
 678         bool did_this = false;
 679         NR::Matrix i2doc(sp_item_i2doc_affine(item));
 680         if (theShape->MakeOffset(theRes,
 681                                  expand? offset : -offset,
 682                                  join_straight, butt_straight,
 683                                  true, p[NR::X], p[NR::Y], radius, &i2doc) == 0) // 0 means the shape was actually changed
 684             did_this = true;
 685
 686         // the rest only makes sense if we actually changed the path
 687         if (did_this) {
 688             theRes->ConvertToShape(theShape, fill_positive);
 689
 690             res->Reset();
 691             theRes->ConvertToForme(res);
 692
 693             if (offset >= 0.5)
 694             {
 695                 res->ConvertEvenLines(0.5);
 696                 res->Simplify(0.5);
 697             }
 698             else
 699             {
 700                 res->ConvertEvenLines(0.5*offset);
 701                 res->Simplify(0.5 * offset);
 702             }
 703
 704             sp_curve_unref(curve);
 705             if (res->descr_cmd.size() > 1) {
 706                 gchar *str = res->svg_dump_path();
 707                 SP_OBJECT_REPR(item)->setAttribute("d", str);
 708                 g_free(str);
 709             } else {
 710                 // TODO: if there's 0 or 1 node left, delete this path altogether
 711             }
 712         }
 713
 714         delete theShape;
 715         delete theRes;
 716         delete orig;
 717         delete res;
 718
 719         if (did_this)
 720             did = true;
 721     }
 722
 723     return did;
 724 }
 725
 726 void
 727 sp_ddc_update_cursors (SPDynaDrawContext *dc)
 728 {
 729     if (dc->is_dilating) {
 730         double radius = get_dilate_radius(dc);
 731         NR::Matrix const sm (NR::scale(radius, radius) * NR::translate(SP_EVENT_CONTEXT(dc)->desktop->point()));
 732         sp_canvas_item_affine_absolute(dc->dilate_area, sm);
 733         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0xff9900ff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 734         sp_canvas_item_show(dc->dilate_area);
 735     }
 736 }
 737
 738 void
 739 sp_ddc_update_toolbox (SPDesktop *desktop, const gchar *id, double value)
 740 {
 741     desktop->setToolboxAdjustmentValue (id, value);
 742 }
 743
 744 static void
 745 calligraphic_cancel(SPDynaDrawContext *dc)
 746 {
 747     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
 748     dc->dragging = FALSE;
 749     dc->is_drawing = false;
 750     sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), 0);
 751             /* Remove all temporary line segments */
 752             while (dc->segments) {
 753                 gtk_object_destroy(GTK_OBJECT(dc->segments->data));
 754                 dc->segments = g_slist_remove(dc->segments, dc->segments->data);
 755             }
 756             /* reset accumulated curve */
 757             sp_curve_reset(dc->accumulated);
 758             clear_current(dc);
 759             if (dc->repr) {
 760                 dc->repr = NULL;
 761             }
 762 }
 763
 764
 765 gint
 766 sp_dyna_draw_context_root_handler(SPEventContext *event_context,
 767                                   GdkEvent *event)
 768 {
 769     SPDynaDrawContext *dc = SP_DYNA_DRAW_CONTEXT(event_context);
 770     SPDesktop *desktop = event_context->desktop;
 771
 772     gint ret = FALSE;
 773
 774     switch (event->type) {
 775         case GDK_BUTTON_PRESS:
 776             if ( event->button.button == 1 ) {
 777
 778                 SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
 779
 780                 if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
 781                     return TRUE;
 782                 }
 783
 784                 NR::Point const button_w(event->button.x,
 785                                          event->button.y);
 786                 NR::Point const button_dt(desktop->w2d(button_w));
 787                 sp_dyna_draw_reset(dc, button_dt);
 788                 sp_dyna_draw_extinput(dc, event);
 789                 sp_dyna_draw_apply(dc, button_dt);
 790                 sp_curve_reset(dc->accumulated);
 791                 if (dc->repr) {
 792                     dc->repr = NULL;
 793                 }
 794
 795                 /* initialize first point */
 796                 dc->npoints = 0;
 797
 798                 sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
 799                                     ( GDK_KEY_PRESS_MASK |
 800                                       GDK_BUTTON_RELEASE_MASK |
 801                                       GDK_POINTER_MOTION_MASK |
 802                                       GDK_BUTTON_PRESS_MASK ),
 803                                     NULL,
 804                                     event->button.time);
 805
 806                 ret = TRUE;
 807
 808                 dc->is_drawing = true;
 809             }
 810             break;
 811         case GDK_MOTION_NOTIFY:
 812         {
 813             NR::Point const motion_w(event->motion.x,
 814                                      event->motion.y);
 815             NR::Point motion_dt(desktop->w2d(motion_w));
 816             sp_dyna_draw_extinput(dc, event);
 817
 818             // draw the dilating cursor
 819             if (event->motion.state & GDK_MOD1_MASK) {
 820                 double radius = get_dilate_radius(dc);
 821                 NR::Matrix const sm (NR::scale(radius, radius) * NR::translate(desktop->w2d(motion_w)));
 822                 sp_canvas_item_affine_absolute(dc->dilate_area, sm);
 823                 sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0xff9900ff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
 824                 sp_canvas_item_show(dc->dilate_area);
 825
 826                 guint num = 0;
 827                 if (!desktop->selection->isEmpty()) {
 828                     num = g_slist_length((GSList *) desktop->selection->itemList());
 829                 }
 830                 if (num == 0) {
 831                     dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Select paths</b> to thin or thicken"));
 832                 } else {
 833                     dc->_message_context->setF(Inkscape::NORMAL_MESSAGE,
 834                                            event->motion.state & GDK_SHIFT_MASK?
 835                                            _("<b>Thickening %d</b> selected paths; without <b>Shift</b> to thin") :
 836                                            _("<b>Thinning %d</b> selected paths; with <b>Shift</b> to thicken"), num);
 837                 }
 838
 839             } else {
 840                 dc->_message_context->clear();
 841                 sp_canvas_item_hide(dc->dilate_area);
 842             }
 843
 844             // dilating:
 845             if (dc->is_drawing && ( event->motion.state & GDK_BUTTON1_MASK ) && event->motion.state & GDK_MOD1_MASK) {
 846                 sp_ddc_dilate (dc, desktop->dt2doc(motion_dt), event->motion.state & GDK_SHIFT_MASK? true : false);
 847                 dc->is_dilating = true;
 848                 // it's slow, so prevent clogging up with events
 849                 gobble_motion_events(GDK_BUTTON1_MASK);
 850                 return TRUE;
 851             }
 852
 853
 854             // for hatching:
 855             double hatch_dist = 0;
 856             NR::Point hatch_unit_vector(0,0);
 857             NR::Point nearest(0,0);
 858             NR::Point pointer(0,0);
 859             NR::Matrix motion_to_curve(NR::identity());
 860
 861             if (event->motion.state & GDK_CONTROL_MASK) { // hatching - sense the item
 862
 863                 SPItem *selected = sp_desktop_selection(desktop)->singleItem();
 864                 if (selected && (SP_IS_SHAPE(selected) || SP_IS_TEXT(selected))) {
 865                     // One item selected, and it's a path;
 866                     // let's try to track it as a guide
 867
 868                     if (selected != dc->hatch_item) {
 869                         dc->hatch_item = selected;
 870                         if (dc->hatch_livarot_path)
 871                             delete dc->hatch_livarot_path;
 872                         dc->hatch_livarot_path = Path_for_item (dc->hatch_item, true, true);
 873                         dc->hatch_livarot_path->ConvertWithBackData(0.01);
 874                     }
 875
 876                     // calculate pointer point in the guide item's coords
 877                     motion_to_curve = sp_item_dt2i_affine(selected) * sp_item_i2doc_affine(selected);
 878                     pointer = motion_dt * motion_to_curve;
 879
 880                     // calculate the nearest point on the guide path
 881                     NR::Maybe<Path::cut_position> position = get_nearest_position_on_Path(dc->hatch_livarot_path, pointer);
 882                     nearest = get_point_on_Path(dc->hatch_livarot_path, position->piece, position->t);
 883
 884
 885                     // distance from pointer to nearest
 886                     hatch_dist = NR::L2(pointer - nearest);
 887                     // unit-length vector
 888                     hatch_unit_vector = (pointer - nearest)/hatch_dist;
 889
 890                     dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Guide path selected</b>; start drawing along the guide with <b>Ctrl</b>"));
 891                 } else {
 892                     dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Select a guide path</b> to track with <b>Ctrl</b>"));
 893                 }
 894             }
 895
 896             if ( dc->is_drawing && ( event->motion.state & GDK_BUTTON1_MASK ) ) {
 897                 dc->dragging = TRUE;
 898
 899                 if (event->motion.state & GDK_CONTROL_MASK && dc->hatch_item) { // hatching
 900
 901 #define SPEED_ELEMENTS 12
 902 #define SPEED_MIN 0.12
 903 #define SPEED_NORMAL 0.65
 904
 905                     // speed is the movement of the nearest point along the guide path, divided by
 906                     // the movement of the pointer at the same period; it is averaged for the last
 907                     // SPEED_ELEMENTS motion events.  Normally, as you track the guide path, speed
 908                     // is about 1, i.e. the nearest point on the path is moved by about the same
 909                     // distance as the pointer. If the speed starts to decrease, we are losing
 910                     // contact with the guide; if it drops below SPEED_MIN, we are on our own and
 911                     // not attracted to guide anymore. Most often this happens when you have
 912                     // tracked to the end of a guide calligraphic stroke and keep moving
 913                     // further. We try to handle this situation gracefully: not stick with the
 914                     // guide forever but let go of it smoothly and without sharp jerks (non-zero
 915                     // mass recommended; with zero mass, jerks are still quite noticeable).
 916
 917                     double speed = 1;
 918                     if (NR::L2(dc->hatch_last_nearest) != 0) {
 919                         // the distance nearest moved since the last motion event
 920                         double nearest_moved = NR::L2(nearest - dc->hatch_last_nearest);
 921                         // the distance pointer moved since the last motion event
 922                         double pointer_moved = NR::L2(pointer - dc->hatch_last_pointer);
 923                         // store them in stacks limited to SPEED_ELEMENTS
 924                         dc->hatch_nearest_past.push_front(nearest_moved);
 925                         if (dc->hatch_nearest_past.size() > SPEED_ELEMENTS)
 926                             dc->hatch_nearest_past.pop_back();
 927                         dc->hatch_pointer_past.push_front(pointer_moved);
 928                         if (dc->hatch_pointer_past.size() > SPEED_ELEMENTS)
 929                             dc->hatch_pointer_past.pop_back();
 930
 931                         // If the stacks are full,
 932                         if (dc->hatch_nearest_past.size() == SPEED_ELEMENTS) {
 933                             // calculate the sums of all stored movements
 934                             double nearest_sum = std::accumulate (dc->hatch_nearest_past.begin(), dc->hatch_nearest_past.end(), 0.0);
 935                             double pointer_sum = std::accumulate (dc->hatch_pointer_past.begin(), dc->hatch_pointer_past.end(), 0.0);
 936                             // and divide to get the speed
 937                             speed = nearest_sum/pointer_sum;
 938                             //g_print ("nearest sum %g  pointer_sum %g  speed %g\n", nearest_sum, pointer_sum, speed);
 939                         }
 940                     }
 941
 942                     if (   dc->hatch_escaped  // already escaped, do not reattach
 943                         || (speed < SPEED_MIN) // stuck; most likely reached end of traced stroke
 944                         || (dc->hatch_spacing > 0 && hatch_dist > 50 * dc->hatch_spacing) // went too far from the guide
 945                         ) {
 946                         // We are NOT attracted to the guide!
 947
 948                         //g_print ("\nlast_nearest %g %g   nearest %g %g  pointer %g %g  pos %d %g\n", dc->last_nearest[NR::X], dc->last_nearest[NR::Y], nearest[NR::X], nearest[NR::Y], pointer[NR::X], pointer[NR::Y], position->piece, position->t);
 949
 950                         // Remember hatch_escaped so we don't get
 951                         // attracted again until the end of this stroke
 952                         dc->hatch_escaped = true;
 953
 954                     } else {
 955
 956                         // Calculate angle cosine of this vector-to-guide and all past vectors
 957                         // summed, to detect if we accidentally flipped to the other side of the
 958                         // guide
 959                         double dot = NR::dot (pointer - nearest, dc->hatch_vector_accumulated);
 960                         dot /= NR::L2(pointer - nearest) * NR::L2(dc->hatch_vector_accumulated);
 961
 962                         if (dc->hatch_spacing != 0) { // spacing was already set
 963                             double target;
 964                             if (speed > SPEED_NORMAL) {
 965                                 // all ok, strictly obey the spacing
 966                                 target = dc->hatch_spacing;
 967                             } else {
 968                                 // looks like we're starting to lose speed,
 969                                 // so _gradually_ let go attraction to prevent jerks
 970                                 target = (dc->hatch_spacing * speed + hatch_dist * (SPEED_NORMAL - speed))/SPEED_NORMAL;
 971                             }
 972                             if (!isNaN(dot) && dot < -0.5) {// flip
 973                                 target = -target;
 974                             }
 975
 976                             // This is the track pointer that we will use instead of the real one
 977                             NR::Point new_pointer = nearest + target * hatch_unit_vector;
 978
 979                             // some limited feedback: allow persistent pulling to slightly change
 980                             // the spacing
 981                             dc->hatch_spacing += (hatch_dist - dc->hatch_spacing)/3500;
 982
 983                             // return it to the desktop coords
 984                             motion_dt = new_pointer * motion_to_curve.inverse();
 985
 986                         } else {
 987                             // this is the first motion event, set the dist
 988                             dc->hatch_spacing = hatch_dist;
 989                         }
 990
 991                         // remember last points
 992                         dc->hatch_last_pointer = pointer;
 993                         dc->hatch_last_nearest = nearest;
 994                         dc->hatch_vector_accumulated += (pointer - nearest);
 995                     }
 996
 997                     dc->_message_context->set(Inkscape::NORMAL_MESSAGE, dc->hatch_escaped? _("Tracking: <b>connection to guide path lost!</b>") : _("<b>Tracking</b> a guide path"));
 998
 999                 } else {
1000                     dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drawing</b> a calligraphic stroke"));
1001                 }
1002
1003                 if (!sp_dyna_draw_apply(dc, motion_dt)) {
1004                     ret = TRUE;
1005                     break;
1006                 }
1007
1008                 if ( dc->cur != dc->last ) {
1009                     sp_dyna_draw_brush(dc);
1010                     g_assert( dc->npoints > 0 );
1011                     fit_and_split(dc, FALSE);
1012                 }
1013                 ret = TRUE;
1014             }
1015
1016             // Draw the hatching circle if necessary
1017             if (event->motion.state & GDK_CONTROL_MASK) {
1018                 if (dc->hatch_spacing == 0 && hatch_dist != 0) {
1019                     // Haven't set spacing yet: gray, center free, update radius live
1020                     NR::Point c = desktop->w2d(motion_w);
1021                     NR::Matrix const sm (NR::scale(hatch_dist, hatch_dist) * NR::translate(c));
1022                     sp_canvas_item_affine_absolute(dc->hatch_area, sm);
1023                     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0x7f7f7fff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1024                     sp_canvas_item_show(dc->hatch_area);
1025                 } else if (dc->dragging && !dc->hatch_escaped) {
1026                     // Tracking: green, center snapped, fixed radius
1027                     NR::Point c = motion_dt;
1028                     NR::Matrix const sm (NR::scale(dc->hatch_spacing, dc->hatch_spacing) * NR::translate(c));
1029                     sp_canvas_item_affine_absolute(dc->hatch_area, sm);
1030                     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0x00FF00ff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1031                     sp_canvas_item_show(dc->hatch_area);
1032                 } else if (dc->dragging && dc->hatch_escaped) {
1033                     // Tracking escaped: red, center free, fixed radius
1034                     NR::Point c = desktop->w2d(motion_w);
1035                     NR::Matrix const sm (NR::scale(dc->hatch_spacing, dc->hatch_spacing) * NR::translate(c));
1036
1037                     sp_canvas_item_affine_absolute(dc->hatch_area, sm);
1038                     sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0xFF0000ff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1039                     sp_canvas_item_show(dc->hatch_area);
1040                 } else {
1041                     // Not drawing but spacing set: gray, center snapped, fixed radius
1042                     NR::Point c = (nearest + dc->hatch_spacing * hatch_unit_vector) * motion_to_curve.inverse();
1043                     if (!isNaN(c[NR::X]) && !isNaN(c[NR::Y])) {
1044                         NR::Matrix const sm (NR::scale(dc->hatch_spacing, dc->hatch_spacing) * NR::translate(c));
1045                         sp_canvas_item_affine_absolute(dc->hatch_area, sm);
1046                         sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(dc->hatch_area), 0x7f7f7fff, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1047                         sp_canvas_item_show(dc->hatch_area);
1048                     }
1049                 }
1050             } else {
1051                 sp_canvas_item_hide(dc->hatch_area);
1052             }
1053         }
1054         break;
1055
1056
1057     case GDK_BUTTON_RELEASE:
1058         sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
1059         dc->is_drawing = false;
1060
1061         if ( dc->is_dilating && event->button.button == 1 ) {
1062             dc->is_dilating = false;
1063             sp_document_done(sp_desktop_document(SP_EVENT_CONTEXT(dc)->desktop),
1064                          SP_VERB_CONTEXT_CALLIGRAPHIC,
1065                          (event->button.state & GDK_SHIFT_MASK ? _("Thicken paths") : _("Thin paths")));
1066             ret = TRUE;
1067         } else if ( dc->dragging && event->button.button == 1 ) {
1068             dc->dragging = FALSE;
1069
1070             NR::Point const motion_w(event->button.x, event->button.y);
1071             NR::Point const motion_dt(desktop->w2d(motion_w));
1072             sp_dyna_draw_apply(dc, motion_dt);
1073
1074             /* Remove all temporary line segments */
1075             while (dc->segments) {
1076                 gtk_object_destroy(GTK_OBJECT(dc->segments->data));
1077                 dc->segments = g_slist_remove(dc->segments, dc->segments->data);
1078             }
1079
1080             /* Create object */
1081             fit_and_split(dc, TRUE);
1082             accumulate_calligraphic(dc);
1083             set_to_accumulated(dc, event->button.state & GDK_SHIFT_MASK); // performs document_done
1084
1085             /* reset accumulated curve */
1086             sp_curve_reset(dc->accumulated);
1087
1088             clear_current(dc);
1089             if (dc->repr) {
1090                 dc->repr = NULL;
1091             }
1092
1093             if (!dc->hatch_pointer_past.empty()) dc->hatch_pointer_past.clear();
1094             if (!dc->hatch_nearest_past.empty()) dc->hatch_nearest_past.clear();
1095             dc->hatch_last_nearest = NR::Point(0,0);
1096             dc->hatch_last_pointer = NR::Point(0,0);
1097             dc->hatch_vector_accumulated = NR::Point(0,0);
1098             dc->hatch_escaped = false;
1099             dc->hatch_item = NULL;
1100             dc->hatch_livarot_path = NULL;
1101
1102             dc->_message_context->clear();
1103             ret = TRUE;
1104         }
1105         break;
1106
1107     case GDK_KEY_PRESS:
1108         switch (get_group0_keyval (&event->key)) {
1109         case GDK_Up:
1110         case GDK_KP_Up:
1111             if (!MOD__CTRL_ONLY) {
1112                 dc->angle += 5.0;
1113                 if (dc->angle > 90.0)
1114                     dc->angle = 90.0;
1115                 sp_ddc_update_toolbox (desktop, "calligraphy-angle", dc->angle);
1116                 ret = TRUE;
1117             }
1118             break;
1119         case GDK_Down:
1120         case GDK_KP_Down:
1121             if (!MOD__CTRL_ONLY) {
1122                 dc->angle -= 5.0;
1123                 if (dc->angle < -90.0)
1124                     dc->angle = -90.0;
1125                 sp_ddc_update_toolbox (desktop, "calligraphy-angle", dc->angle);
1126                 ret = TRUE;
1127             }
1128             break;
1129         case GDK_Right:
1130         case GDK_KP_Right:
1131             if (!MOD__CTRL_ONLY) {
1132                 dc->width += 0.01;
1133                 if (dc->width > 1.0)
1134                     dc->width = 1.0;
1135                 sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100); // the same spinbutton is for alt+x
1136                 sp_ddc_update_cursors(dc);
1137                 ret = TRUE;
1138             }
1139             break;
1140         case GDK_Left:
1141         case GDK_KP_Left:
1142             if (!MOD__CTRL_ONLY) {
1143                 dc->width -= 0.01;
1144                 if (dc->width < 0.01)
1145                     dc->width = 0.01;
1146                 sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100);
1147                 sp_ddc_update_cursors(dc);
1148                 ret = TRUE;
1149             }
1150             break;
1151         case GDK_Home:
1152         case GDK_KP_Home:
1153             dc->width = 0.01;
1154             sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100);
1155             sp_ddc_update_cursors(dc);
1156             ret = TRUE;
1157             break;
1158         case GDK_End:
1159         case GDK_KP_End:
1160             dc->width = 1.0;
1161             sp_ddc_update_toolbox (desktop, "altx-calligraphy", dc->width * 100);
1162             sp_ddc_update_cursors(dc);
1163             ret = TRUE;
1164             break;
1165         case GDK_x:
1166         case GDK_X:
1167             if (MOD__ALT_ONLY) {
1168                 desktop->setToolboxFocusTo ("altx-calligraphy");
1169                 ret = TRUE;
1170             }
1171             break;
1172         case GDK_Escape:
1173             if (dc->is_drawing) {
1174                 // if drawing, cancel, otherwise pass it up for deselecting
1175                 calligraphic_cancel (dc);
1176                 ret = TRUE;
1177             }
1178             break;
1179         case GDK_z:
1180         case GDK_Z:
1181             if (MOD__CTRL_ONLY && dc->is_drawing) {
1182                 // if drawing, cancel, otherwise pass it up for undo
1183                 calligraphic_cancel (dc);
1184                 ret = TRUE;
1185             }
1186             break;
1187         case GDK_Meta_L:
1188         case GDK_Meta_R:
1189             event_context->cursor_shape = cursor_thicken_xpm;
1190             sp_event_context_update_cursor(event_context);
1191             break;
1192         case GDK_Alt_L:
1193         case GDK_Alt_R:
1194             if (MOD__SHIFT) {
1195                 event_context->cursor_shape = cursor_thicken_xpm;
1196                 sp_event_context_update_cursor(event_context);
1197             } else {
1198                 event_context->cursor_shape = cursor_thin_xpm;
1199                 sp_event_context_update_cursor(event_context);
1200             }
1201             break;
1202         case GDK_Shift_L:
1203         case GDK_Shift_R:
1204             if (MOD__ALT) {
1205                 event_context->cursor_shape = cursor_thicken_xpm;
1206                 sp_event_context_update_cursor(event_context);
1207             }
1208             break;
1209         default:
1210             break;
1211         }
1212         break;
1213
1214     case GDK_KEY_RELEASE:
1215         switch (get_group0_keyval(&event->key)) {
1216             case GDK_Control_L:
1217             case GDK_Control_R:
1218                 dc->_message_context->clear();
1219                 dc->hatch_spacing = 0;
1220                 break;
1221             case GDK_Alt_L:
1222             case GDK_Alt_R:
1223                 event_context->cursor_shape = cursor_calligraphy_xpm;
1224                 sp_event_context_update_cursor(event_context);
1225                 break;
1226             case GDK_Shift_L:
1227             case GDK_Shift_R:
1228                 if (MOD__ALT) {
1229                     event_context->cursor_shape = cursor_thin_xpm;
1230                     sp_event_context_update_cursor(event_context);
1231                 }
1232                 break;
1233             case GDK_Meta_L:
1234             case GDK_Meta_R:
1235                 event_context->cursor_shape = cursor_calligraphy_xpm;
1236                 sp_event_context_update_cursor(event_context);
1237             break;
1238             default:
1239                 break;
1240         }
1241
1242     default:
1243         break;
1244     }
1245
1246     if (!ret) {
1247         if (((SPEventContextClass *) parent_class)->root_handler) {
1248             ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
1249         }
1250     }
1251
1252     return ret;
1253 }
1254
1255
1256 static void
1257 clear_current(SPDynaDrawContext *dc)
1258 {
1259     /* reset bpath */
1260     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), NULL);
1261     /* reset curve */
1262     sp_curve_reset(dc->currentcurve);
1263     sp_curve_reset(dc->cal1);
1264     sp_curve_reset(dc->cal2);
1265     /* reset points */
1266     dc->npoints = 0;
1267 }
1268
1269 static void
1270 set_to_accumulated(SPDynaDrawContext *dc, bool unionize)
1271 {
1272     SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
1273
1274     if (!sp_curve_empty(dc->accumulated)) {
1275         NArtBpath *abp;
1276         gchar *str;
1277
1278         if (!dc->repr) {
1279             /* Create object */
1280             Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
1281             Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
1282
1283             /* Set style */
1284             sp_desktop_apply_style_tool (desktop, repr, "tools.calligraphic", false);
1285
1286             dc->repr = repr;
1287
1288             SPItem *item=SP_ITEM(desktop->currentLayer()->appendChildRepr(dc->repr));
1289             Inkscape::GC::release(dc->repr);
1290             item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
1291             item->updateRepr();
1292         }
1293         abp = nr_artpath_affine(sp_curve_first_bpath(dc->accumulated), sp_desktop_dt2root_affine(desktop));
1294         str = sp_svg_write_path(abp);
1295         g_assert( str != NULL );
1296         g_free(abp);
1297         dc->repr->setAttribute("d", str);
1298         g_free(str);
1299
1300         if (unionize) {
1301             sp_desktop_selection(desktop)->add(dc->repr);
1302             sp_selected_path_union_skip_undo();
1303         } else {
1304             if (dc->keep_selected) {
1305                 sp_desktop_selection(desktop)->set(dc->repr);
1306             } else {
1307                 sp_desktop_selection(desktop)->clear();
1308             }
1309         }
1310
1311     } else {
1312         if (dc->repr) {
1313             sp_repr_unparent(dc->repr);
1314         }
1315         dc->repr = NULL;
1316     }
1317
1318     sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_CALLIGRAPHIC,
1319                      _("Draw calligraphic stroke"));
1320 }
1321
1322 static void
1323 add_cap(SPCurve *curve,
1324         NR::Point const &pre, NR::Point const &from,
1325         NR::Point const &to, NR::Point const &post,
1326         double rounding)
1327 {
1328     NR::Point vel = rounding * NR::rot90( to - from ) / sqrt(2.0);
1329     double mag = NR::L2(vel);
1330
1331     NR::Point v_in = from - pre;
1332     double mag_in = NR::L2(v_in);
1333     if ( mag_in > DYNA_EPSILON ) {
1334         v_in = mag * v_in / mag_in;
1335     } else {
1336         v_in = NR::Point(0, 0);
1337     }
1338
1339     NR::Point v_out = to - post;
1340     double mag_out = NR::L2(v_out);
1341     if ( mag_out > DYNA_EPSILON ) {
1342         v_out = mag * v_out / mag_out;
1343     } else {
1344         v_out = NR::Point(0, 0);
1345     }
1346
1347     if ( NR::L2(v_in) > DYNA_EPSILON || NR::L2(v_out) > DYNA_EPSILON ) {
1348         sp_curve_curveto(curve, from + v_in, to + v_out, to);
1349     }
1350 }
1351
1352 static void
1353 accumulate_calligraphic(SPDynaDrawContext *dc)
1354 {
1355     if ( !sp_curve_empty(dc->cal1) && !sp_curve_empty(dc->cal2) ) {
1356         sp_curve_reset(dc->accumulated); /*  Is this required ?? */
1357         SPCurve *rev_cal2 = sp_curve_reverse(dc->cal2);
1358
1359         g_assert(dc->cal1->end > 1);
1360         g_assert(rev_cal2->end > 1);
1361         g_assert(SP_CURVE_SEGMENT(dc->cal1, 0)->code == NR_MOVETO_OPEN);
1362         g_assert(SP_CURVE_SEGMENT(rev_cal2, 0)->code == NR_MOVETO_OPEN);
1363         g_assert(SP_CURVE_SEGMENT(dc->cal1, 1)->code == NR_CURVETO);
1364         g_assert(SP_CURVE_SEGMENT(rev_cal2, 1)->code == NR_CURVETO);
1365         g_assert(SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->code == NR_CURVETO);
1366         g_assert(SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->code == NR_CURVETO);
1367
1368         sp_curve_append(dc->accumulated, dc->cal1, FALSE);
1369
1370         add_cap(dc->accumulated, SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->c(2), SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->c(3), SP_CURVE_SEGMENT(rev_cal2, 0)->c(3), SP_CURVE_SEGMENT(rev_cal2, 1)->c(1), dc->cap_rounding);
1371
1372         sp_curve_append(dc->accumulated, rev_cal2, TRUE);
1373
1374         add_cap(dc->accumulated, SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->c(2), SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->c(3), SP_CURVE_SEGMENT(dc->cal1, 0)->c(3), SP_CURVE_SEGMENT(dc->cal1, 1)->c(1), dc->cap_rounding);
1375
1376         sp_curve_closepath(dc->accumulated);
1377
1378         sp_curve_unref(rev_cal2);
1379
1380         sp_curve_reset(dc->cal1);
1381         sp_curve_reset(dc->cal2);
1382     }
1383 }
1384
1385 static double square(double const x)
1386 {
1387     return x * x;
1388 }
1389
1390 static void
1391 fit_and_split(SPDynaDrawContext *dc, gboolean release)
1392 {
1393     double const tolerance_sq = square( NR::expansion(SP_EVENT_CONTEXT(dc)->desktop->w2d()) * TOLERANCE_CALLIGRAPHIC );
1394
1395 #ifdef DYNA_DRAW_VERBOSE
1396     g_print("[F&S:R=%c]", release?'T':'F');
1397 #endif
1398
1399     if (!( dc->npoints > 0 && dc->npoints < SAMPLING_SIZE ))
1400         return; // just clicked
1401
1402     if ( dc->npoints == SAMPLING_SIZE - 1 || release ) {
1403 #define BEZIER_SIZE       4
1404 #define BEZIER_MAX_BEZIERS  8
1405 #define BEZIER_MAX_LENGTH ( BEZIER_SIZE * BEZIER_MAX_BEZIERS )
1406
1407 #ifdef DYNA_DRAW_VERBOSE
1408         g_print("[F&S:#] dc->npoints:%d, release:%s\n",
1409                 dc->npoints, release ? "TRUE" : "FALSE");
1410 #endif
1411
1412         /* Current calligraphic */
1413         if ( dc->cal1->end == 0 || dc->cal2->end == 0 ) {
1414             /* dc->npoints > 0 */
1415             /* g_print("calligraphics(1|2) reset\n"); */
1416             sp_curve_reset(dc->cal1);
1417             sp_curve_reset(dc->cal2);
1418
1419             sp_curve_moveto(dc->cal1, dc->point1[0]);
1420             sp_curve_moveto(dc->cal2, dc->point2[0]);
1421         }
1422
1423         NR::Point b1[BEZIER_MAX_LENGTH];
1424         gint const nb1 = sp_bezier_fit_cubic_r(b1, dc->point1, dc->npoints,
1425                                                tolerance_sq, BEZIER_MAX_BEZIERS);
1426         g_assert( nb1 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b1)) );
1427
1428         NR::Point b2[BEZIER_MAX_LENGTH];
1429         gint const nb2 = sp_bezier_fit_cubic_r(b2, dc->point2, dc->npoints,
1430                                                tolerance_sq, BEZIER_MAX_BEZIERS);
1431         g_assert( nb2 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b2)) );
1432
1433         if ( nb1 != -1 && nb2 != -1 ) {
1434             /* Fit and draw and reset state */
1435 #ifdef DYNA_DRAW_VERBOSE
1436             g_print("nb1:%d nb2:%d\n", nb1, nb2);
1437 #endif
1438             /* CanvasShape */
1439             if (! release) {
1440                 sp_curve_reset(dc->currentcurve);
1441                 sp_curve_moveto(dc->currentcurve, b1[0]);
1442                 for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
1443                     sp_curve_curveto(dc->currentcurve, bp1[1],
1444                                      bp1[2], bp1[3]);
1445                 }
1446                 sp_curve_lineto(dc->currentcurve,
1447                                 b2[BEZIER_SIZE*(nb2-1) + 3]);
1448                 for (NR::Point *bp2 = b2 + BEZIER_SIZE * ( nb2 - 1 ); bp2 >= b2; bp2 -= BEZIER_SIZE) {
1449                     sp_curve_curveto(dc->currentcurve, bp2[2], bp2[1], bp2[0]);
1450                 }
1451                 // FIXME: dc->segments is always NULL at this point??
1452                 if (!dc->segments) { // first segment
1453                     add_cap(dc->currentcurve, b2[1], b2[0], b1[0], b1[1], dc->cap_rounding);
1454                 }
1455                 sp_curve_closepath(dc->currentcurve);
1456                 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
1457             }
1458
1459             /* Current calligraphic */
1460             for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
1461                 sp_curve_curveto(dc->cal1, bp1[1], bp1[2], bp1[3]);
1462             }
1463             for (NR::Point *bp2 = b2; bp2 < b2 + BEZIER_SIZE * nb2; bp2 += BEZIER_SIZE) {
1464                 sp_curve_curveto(dc->cal2, bp2[1], bp2[2], bp2[3]);
1465             }
1466         } else {
1467             /* fixme: ??? */
1468 #ifdef DYNA_DRAW_VERBOSE
1469             g_print("[fit_and_split] failed to fit-cubic.\n");
1470 #endif
1471             draw_temporary_box(dc);
1472
1473             for (gint i = 1; i < dc->npoints; i++) {
1474                 sp_curve_lineto(dc->cal1, dc->point1[i]);
1475             }
1476             for (gint i = 1; i < dc->npoints; i++) {
1477                 sp_curve_lineto(dc->cal2, dc->point2[i]);
1478             }
1479         }
1480
1481         /* Fit and draw and copy last point */
1482 #ifdef DYNA_DRAW_VERBOSE
1483         g_print("[%d]Yup\n", dc->npoints);
1484 #endif
1485         if (!release) {
1486             g_assert(!sp_curve_empty(dc->currentcurve));
1487
1488             SPCanvasItem *cbp = sp_canvas_item_new(sp_desktop_sketch(SP_EVENT_CONTEXT(dc)->desktop),
1489                                                    SP_TYPE_CANVAS_BPATH,
1490                                                    NULL);
1491             SPCurve *curve = sp_curve_copy(dc->currentcurve);
1492             sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH (cbp), curve);
1493             sp_curve_unref(curve);
1494
1495             guint32 fillColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", true);
1496             //guint32 strokeColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", false);
1497             double opacity = sp_desktop_get_master_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic");
1498             double fillOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", true);
1499             //double strokeOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_DESKTOP, "tools.calligraphic", false);
1500             sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(cbp), ((fillColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*fillOpacity)), SP_WIND_RULE_EVENODD);
1501             //on second thougtht don't do stroke yet because we don't have stoke-width yet and because stoke appears between segments while drawing
1502             //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);
1503             sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
1504             /* fixme: Cannot we cascade it to root more clearly? */
1505             g_signal_connect(G_OBJECT(cbp), "event", G_CALLBACK(sp_desktop_root_handler), SP_EVENT_CONTEXT(dc)->desktop);
1506
1507             dc->segments = g_slist_prepend(dc->segments, cbp);
1508         }
1509
1510         dc->point1[0] = dc->point1[dc->npoints - 1];
1511         dc->point2[0] = dc->point2[dc->npoints - 1];
1512         dc->npoints = 1;
1513     } else {
1514         draw_temporary_box(dc);
1515     }
1516 }
1517
1518 static void
1519 draw_temporary_box(SPDynaDrawContext *dc)
1520 {
1521     sp_curve_reset(dc->currentcurve);
1522
1523     sp_curve_moveto(dc->currentcurve, dc->point1[dc->npoints-1]);
1524     for (gint i = dc->npoints-2; i >= 0; i--) {
1525         sp_curve_lineto(dc->currentcurve, dc->point1[i]);
1526     }
1527     for (gint i = 0; i < dc->npoints; i++) {
1528         sp_curve_lineto(dc->currentcurve, dc->point2[i]);
1529     }
1530     if (dc->npoints >= 2) {
1531         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);
1532     }
1533
1534     sp_curve_closepath(dc->currentcurve);
1535     sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
1536 }
1537
1538 /*
1539   Local Variables:
1540   mode:c++
1541   c-file-style:"stroustrup"
1542   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
1543   indent-tabs-mode:nil
1544   fill-column:99
1545   End:
1546 */
1547 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :