1 /** \file
2 * Pencil event context implementation.
3 */
5 /*
6 * Authors:
7 * Lauris Kaplinski <lauris@kaplinski.com>
8 * bulia byak <buliabyak@users.sf.net>
9 *
10 * Copyright (C) 2000 Lauris Kaplinski
11 * Copyright (C) 2000-2001 Ximian, Inc.
12 * Copyright (C) 2002 Lauris Kaplinski
13 * Copyright (C) 2004 Monash University
14 *
15 * Released under GNU GPL, read the file 'COPYING' for more information
16 */
18 #include <gdk/gdkkeysyms.h>
20 #include "pencil-context.h"
21 #include "desktop.h"
22 #include "desktop-handles.h"
23 #include "selection.h"
24 #include "draw-anchor.h"
25 #include "message-stack.h"
26 #include "message-context.h"
27 #include "modifier-fns.h"
28 #include "sp-path.h"
29 #include "prefs-utils.h"
30 #include "snap.h"
31 #include "pixmaps/cursor-pencil.xpm"
32 #include "pixmaps/cursor-pencil.pixbuf"
33 #include "display/bezier-utils.h"
34 #include "display/canvas-bpath.h"
35 #include <glibmm/i18n.h>
36 #include "libnr/in-svg-plane.h"
37 #include "libnr/n-art-bpath.h"
38 #include "context-fns.h"
39 #include "sp-namedview.h"
41 static void sp_pencil_context_class_init(SPPencilContextClass *klass);
42 static void sp_pencil_context_init(SPPencilContext *pc);
43 static void sp_pencil_context_setup(SPEventContext *ec);
44 static void sp_pencil_context_dispose(GObject *object);
46 static gint sp_pencil_context_root_handler(SPEventContext *event_context, GdkEvent *event);
47 static gint pencil_handle_button_press(SPPencilContext *const pc, GdkEventButton const &bevent);
48 static gint pencil_handle_motion_notify(SPPencilContext *const pc, GdkEventMotion const &mevent);
49 static gint pencil_handle_button_release(SPPencilContext *const pc, GdkEventButton const &revent);
50 static gint pencil_handle_key_press(SPPencilContext *const pc, guint const keyval, guint const state);
52 static void spdc_set_startpoint(SPPencilContext *pc, NR::Point const p);
53 static void spdc_set_endpoint(SPPencilContext *pc, NR::Point const p);
54 static void spdc_finish_endpoint(SPPencilContext *pc);
55 static void spdc_add_freehand_point(SPPencilContext *pc, NR::Point p, guint state);
56 static void fit_and_split(SPPencilContext *pc);
59 static SPDrawContextClass *pencil_parent_class;
61 /**
62 * Register SPPencilContext class with Gdk and return its type number.
63 */
64 GType
65 sp_pencil_context_get_type()
66 {
67 static GType type = 0;
68 if (!type) {
69 GTypeInfo info = {
70 sizeof(SPPencilContextClass),
71 NULL, NULL,
72 (GClassInitFunc) sp_pencil_context_class_init,
73 NULL, NULL,
74 sizeof(SPPencilContext),
75 4,
76 (GInstanceInitFunc) sp_pencil_context_init,
77 NULL, /* value_table */
78 };
79 type = g_type_register_static(SP_TYPE_DRAW_CONTEXT, "SPPencilContext", &info, (GTypeFlags)0);
80 }
81 return type;
82 }
84 /**
85 * Initialize SPPencilContext vtable.
86 */
87 static void
88 sp_pencil_context_class_init(SPPencilContextClass *klass)
89 {
90 GObjectClass *object_class;
91 SPEventContextClass *event_context_class;
93 object_class = (GObjectClass *) klass;
94 event_context_class = (SPEventContextClass *) klass;
96 pencil_parent_class = (SPDrawContextClass*)g_type_class_peek_parent(klass);
98 object_class->dispose = sp_pencil_context_dispose;
100 event_context_class->setup = sp_pencil_context_setup;
101 event_context_class->root_handler = sp_pencil_context_root_handler;
102 }
104 /**
105 * Callback to initialize SPPencilContext object.
106 */
107 static void
108 sp_pencil_context_init(SPPencilContext *pc)
109 {
110 SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
112 event_context->cursor_shape = cursor_pencil_xpm;
113 event_context->cursor_pixbuf = gdk_pixbuf_new_from_inline(
114 -1,
115 cursor_pencil_pixbuf,
116 FALSE,
117 NULL);
118 event_context->hot_x = 4;
119 event_context->hot_y = 4;
121 pc->npoints = 0;
122 pc->state = SP_PENCIL_CONTEXT_IDLE;
123 pc->req_tangent = NR::Point(0, 0);
124 }
126 /**
127 * Callback to setup SPPencilContext object.
128 */
129 static void
130 sp_pencil_context_setup(SPEventContext *ec)
131 {
132 if (prefs_get_int_attribute("tools.freehand.pencil", "selcue", 0) != 0) {
133 ec->enableSelectionCue();
134 }
136 if (((SPEventContextClass *) pencil_parent_class)->setup) {
137 ((SPEventContextClass *) pencil_parent_class)->setup(ec);
138 }
140 SPPencilContext *const pc = SP_PENCIL_CONTEXT(ec);
141 pc->is_drawing = false;
143 pc->anchor_statusbar = false;
144 }
146 static void
147 sp_pencil_context_dispose(GObject *object)
148 {
149 G_OBJECT_CLASS(pencil_parent_class)->dispose(object);
150 }
152 /** Snaps new node relative to the previous node. */
153 static void
154 spdc_endpoint_snap(SPPencilContext const *pc, NR::Point &p, guint const state)
155 {
156 spdc_endpoint_snap_rotation(pc, p, pc->p[0], state);
157 spdc_endpoint_snap_free(pc, p, state);
158 }
160 /**
161 * Callback for handling all pencil context events.
162 */
163 gint
164 sp_pencil_context_root_handler(SPEventContext *const ec, GdkEvent *event)
165 {
166 SPPencilContext *const pc = SP_PENCIL_CONTEXT(ec);
168 gint ret = FALSE;
170 switch (event->type) {
171 case GDK_BUTTON_PRESS:
172 ret = pencil_handle_button_press(pc, event->button);
173 break;
175 case GDK_MOTION_NOTIFY:
176 ret = pencil_handle_motion_notify(pc, event->motion);
177 break;
179 case GDK_BUTTON_RELEASE:
180 ret = pencil_handle_button_release(pc, event->button);
181 break;
183 case GDK_KEY_PRESS:
184 ret = pencil_handle_key_press(pc, get_group0_keyval (&event->key), event->key.state);
185 break;
187 default:
188 break;
189 }
191 if (!ret) {
192 gint (*const parent_root_handler)(SPEventContext *, GdkEvent *)
193 = ((SPEventContextClass *) pencil_parent_class)->root_handler;
194 if (parent_root_handler) {
195 ret = parent_root_handler(ec, event);
196 }
197 }
199 return ret;
200 }
202 static gint
203 pencil_handle_button_press(SPPencilContext *const pc, GdkEventButton const &bevent)
204 {
205 gint ret = FALSE;
206 if ( bevent.button == 1 ) {
208 SPDrawContext *dc = SP_DRAW_CONTEXT (pc);
209 SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
210 Inkscape::Selection *selection = sp_desktop_selection(desktop);
212 if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
213 return TRUE;
214 }
216 NR::Point const button_w(bevent.x, bevent.y);
218 /* Find desktop coordinates */
219 NR::Point p = pc->desktop->w2d(button_w);
221 /* Test whether we hit any anchor. */
222 SPDrawAnchor *anchor = spdc_test_inside(pc, button_w);
224 switch (pc->state) {
225 case SP_PENCIL_CONTEXT_ADDLINE:
226 /* Current segment will be finished with release */
227 ret = TRUE;
228 break;
229 default:
230 /* Set first point of sequence */
231 if (anchor) {
232 p = anchor->dp;
233 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Continuing selected path"));
234 } else {
236 if (!(bevent.state & GDK_SHIFT_MASK)) {
238 // This is the first click of a new curve; deselect item so that
239 // this curve is not combined with it (unless it is drawn from its
240 // anchor, which is handled by the sibling branch above)
241 selection->clear();
242 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Creating new path"));
243 SnapManager const &m = desktop->namedview->snap_manager;
244 p = m.freeSnap(Inkscape::Snapper::BBOX_POINT | Inkscape::Snapper::SNAP_POINT, p, NULL).getPoint();
245 } else if (selection->singleItem() && SP_IS_PATH(selection->singleItem())) {
246 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Appending to selected path"));
247 }
248 }
249 pc->sa = anchor;
250 spdc_set_startpoint(pc, p);
251 ret = TRUE;
252 break;
253 }
255 pc->is_drawing = true;
256 }
257 return ret;
258 }
260 static gint
261 pencil_handle_motion_notify(SPPencilContext *const pc, GdkEventMotion const &mevent)
262 {
263 gint ret = FALSE;
264 SPDesktop *const dt = pc->desktop;
266 if (mevent.state & GDK_BUTTON2_MASK || mevent.state & GDK_BUTTON3_MASK) {
267 // allow middle-button scrolling
268 return FALSE;
269 }
271 if ( ( mevent.state & GDK_BUTTON1_MASK ) && !pc->grab && pc->is_drawing) {
272 /* Grab mouse, so release will not pass unnoticed */
273 pc->grab = SP_CANVAS_ITEM(dt->acetate);
274 sp_canvas_item_grab(pc->grab, ( GDK_KEY_PRESS_MASK | GDK_BUTTON_PRESS_MASK |
275 GDK_BUTTON_RELEASE_MASK |
276 GDK_POINTER_MOTION_MASK ),
277 NULL, mevent.time);
278 }
280 /* Find desktop coordinates */
281 NR::Point p = dt->w2d(NR::Point(mevent.x, mevent.y));
283 /* Test whether we hit any anchor. */
284 SPDrawAnchor *anchor = spdc_test_inside(pc, NR::Point(mevent.x, mevent.y));
286 switch (pc->state) {
287 case SP_PENCIL_CONTEXT_ADDLINE:
288 /* Set red endpoint */
289 if (anchor) {
290 p = anchor->dp;
291 } else {
292 spdc_endpoint_snap(pc, p, mevent.state);
293 }
294 spdc_set_endpoint(pc, p);
295 ret = TRUE;
296 break;
297 default:
298 /* We may be idle or already freehand */
299 if ( mevent.state & GDK_BUTTON1_MASK && pc->is_drawing ) {
300 pc->state = SP_PENCIL_CONTEXT_FREEHAND;
301 if ( !pc->sa && !pc->green_anchor ) {
302 /* Create green anchor */
303 pc->green_anchor = sp_draw_anchor_new(pc, pc->green_curve, TRUE, pc->p[0]);
304 }
305 /** \todo
306 * fixme: I am not sure whether we want to snap to anchors
307 * in middle of freehand (Lauris)
308 */
309 if (anchor) {
310 p = anchor->dp;
311 } else if ((mevent.state & GDK_SHIFT_MASK) == 0) {
312 SnapManager const &m = dt->namedview->snap_manager;
313 p = m.freeSnap(Inkscape::Snapper::BBOX_POINT | Inkscape::Snapper::SNAP_POINT, p, NULL).getPoint();
314 }
315 if ( pc->npoints != 0 ) { // buttonpress may have happened before we entered draw context!
316 spdc_add_freehand_point(pc, p, mevent.state);
317 ret = TRUE;
318 }
320 if (anchor && !pc->anchor_statusbar) {
321 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Release</b> here to close and finish the path."));
322 pc->anchor_statusbar = true;
323 } else if (!anchor && pc->anchor_statusbar) {
324 pc->_message_context->clear();
325 pc->anchor_statusbar = false;
326 } else if (!anchor) {
327 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("Drawing a freehand path"));
328 }
330 } else {
331 if (anchor && !pc->anchor_statusbar) {
332 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drag</b> to continue the path from this point."));
333 pc->anchor_statusbar = true;
334 } else if (!anchor && pc->anchor_statusbar) {
335 pc->_message_context->clear();
336 pc->anchor_statusbar = false;
337 }
338 }
339 break;
340 }
341 return ret;
342 }
344 static gint
345 pencil_handle_button_release(SPPencilContext *const pc, GdkEventButton const &revent)
346 {
347 gint ret = FALSE;
349 if ( revent.button == 1 && pc->is_drawing) {
350 SPDesktop *const dt = pc->desktop;
352 pc->is_drawing = false;
354 /* Find desktop coordinates */
355 NR::Point p = dt->w2d(NR::Point(revent.x, revent.y));
357 /* Test whether we hit any anchor. */
358 SPDrawAnchor *anchor = spdc_test_inside(pc, NR::Point(revent.x,
359 revent.y));
361 switch (pc->state) {
362 case SP_PENCIL_CONTEXT_IDLE:
363 /* Releasing button in idle mode means single click */
364 /* We have already set up start point/anchor in button_press */
365 pc->state = SP_PENCIL_CONTEXT_ADDLINE;
366 ret = TRUE;
367 break;
368 case SP_PENCIL_CONTEXT_ADDLINE:
369 /* Finish segment now */
370 if (anchor) {
371 p = anchor->dp;
372 } else {
373 spdc_endpoint_snap(pc, p, revent.state);
374 }
375 pc->ea = anchor;
376 spdc_set_endpoint(pc, p);
377 spdc_finish_endpoint(pc);
378 pc->state = SP_PENCIL_CONTEXT_IDLE;
379 ret = TRUE;
380 break;
381 case SP_PENCIL_CONTEXT_FREEHAND:
382 /* Finish segment now */
383 /// \todo fixme: Clean up what follows (Lauris)
384 if (anchor) {
385 p = anchor->dp;
386 }
387 pc->ea = anchor;
388 /* Write curves to object */
390 dt->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Finishing freehand"));
392 spdc_concat_colors_and_flush(pc, FALSE);
393 pc->sa = NULL;
394 pc->ea = NULL;
395 if (pc->green_anchor) {
396 pc->green_anchor = sp_draw_anchor_destroy(pc->green_anchor);
397 }
398 pc->state = SP_PENCIL_CONTEXT_IDLE;
399 ret = TRUE;
400 break;
401 default:
402 break;
403 }
405 if (pc->grab) {
406 /* Release grab now */
407 sp_canvas_item_ungrab(pc->grab, revent.time);
408 pc->grab = NULL;
409 }
411 pc->grab = NULL;
412 ret = TRUE;
413 }
414 return ret;
415 }
417 static gint
418 pencil_handle_key_press(SPPencilContext *const pc, guint const keyval, guint const state)
419 {
420 gint ret = FALSE;
421 switch (keyval) {
422 case GDK_Up:
423 case GDK_Down:
424 case GDK_KP_Up:
425 case GDK_KP_Down:
426 // Prevent the zoom field from activation.
427 if (!mod_ctrl_only(state)) {
428 ret = TRUE;
429 }
430 break;
431 default:
432 break;
433 }
434 return ret;
435 }
437 /**
438 * Reset points and set new starting point.
439 */
440 static void
441 spdc_set_startpoint(SPPencilContext *const pc, NR::Point const p)
442 {
443 pc->npoints = 0;
444 pc->red_curve_is_valid = false;
445 if (in_svg_plane(p)) {
446 pc->p[pc->npoints++] = p;
447 }
448 }
450 /**
451 * Change moving endpoint position.
452 * <ul>
453 * <li>Ctrl constrains to moving to H/V direction, snapping in given direction.
454 * <li>Otherwise we snap freely to whatever attractors are available.
455 * </ul>
456 *
457 * Number of points is (re)set to 2 always, 2nd point is modified.
458 * We change RED curve.
459 */
460 static void
461 spdc_set_endpoint(SPPencilContext *const pc, NR::Point const p)
462 {
463 if (pc->npoints == 0) {
464 return;
465 /* May occur if first point wasn't in SVG plane (e.g. weird w2d transform, perhaps from bad
466 * zoom setting).
467 */
468 }
469 g_return_if_fail( pc->npoints > 0 );
471 sp_curve_reset(pc->red_curve);
472 if ( ( p == pc->p[0] )
473 || !in_svg_plane(p) )
474 {
475 pc->npoints = 1;
476 } else {
477 pc->p[1] = p;
478 pc->npoints = 2;
480 sp_curve_moveto(pc->red_curve, pc->p[0]);
481 sp_curve_lineto(pc->red_curve, pc->p[1]);
482 pc->red_curve_is_valid = true;
484 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
485 }
486 }
488 /**
489 * Finalize addline.
490 *
491 * \todo
492 * fixme: I'd like remove red reset from concat colors (lauris).
493 * Still not sure, how it will make most sense.
494 */
495 static void
496 spdc_finish_endpoint(SPPencilContext *const pc)
497 {
498 if ( ( SP_CURVE_LENGTH(pc->red_curve) != 2 )
499 || ( SP_CURVE_SEGMENT(pc->red_curve, 0)->c(3) ==
500 SP_CURVE_SEGMENT(pc->red_curve, 1)->c(3) ) )
501 {
502 sp_curve_reset(pc->red_curve);
503 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), NULL);
504 } else {
505 /* Write curves to object. */
506 spdc_concat_colors_and_flush(pc, FALSE);
507 pc->sa = NULL;
508 pc->ea = NULL;
509 }
510 }
512 static void
513 spdc_add_freehand_point(SPPencilContext *pc, NR::Point p, guint state)
514 {
515 g_assert( pc->npoints > 0 );
516 g_return_if_fail(unsigned(pc->npoints) < G_N_ELEMENTS(pc->p));
518 if ( ( p != pc->p[ pc->npoints - 1 ] )
519 && in_svg_plane(p) )
520 {
521 pc->p[pc->npoints++] = p;
522 fit_and_split(pc);
523 }
524 }
526 static inline double
527 square(double const x)
528 {
529 return x * x;
530 }
532 static void
533 fit_and_split(SPPencilContext *pc)
534 {
535 g_assert( pc->npoints > 1 );
537 double const tolerance_sq = square( NR::expansion(pc->desktop->w2d())
538 * prefs_get_double_attribute_limited("tools.freehand.pencil",
539 "tolerance", 10.0, 1.0, 100.0) );
541 NR::Point b[4];
542 g_assert(is_zero(pc->req_tangent)
543 || is_unit_vector(pc->req_tangent));
544 NR::Point const tHatEnd(0, 0);
545 int const n_segs = sp_bezier_fit_cubic_full(b, NULL, pc->p, pc->npoints,
546 pc->req_tangent, tHatEnd, tolerance_sq, 1);
547 if ( n_segs > 0
548 && unsigned(pc->npoints) < G_N_ELEMENTS(pc->p) )
549 {
550 /* Fit and draw and reset state */
551 sp_curve_reset(pc->red_curve);
552 sp_curve_moveto(pc->red_curve, b[0]);
553 sp_curve_curveto(pc->red_curve, b[1], b[2], b[3]);
554 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
555 pc->red_curve_is_valid = true;
556 } else {
557 /* Fit and draw and copy last point */
559 g_assert(!sp_curve_empty(pc->red_curve));
561 /* Set up direction of next curve. */
562 {
563 NArtBpath const &last_seg = *sp_curve_last_bpath(pc->red_curve);
564 pc->p[0] = last_seg.c(3);
565 pc->npoints = 1;
566 g_assert( last_seg.code == NR_CURVETO );
567 /* Relevance: validity of last_seg.c(2). */
568 NR::Point const req_vec( pc->p[0] - last_seg.c(2) );
569 pc->req_tangent = ( ( NR::is_zero(req_vec) || !in_svg_plane(req_vec) )
570 ? NR::Point(0, 0)
571 : NR::unit_vector(req_vec) );
572 }
574 sp_curve_append_continuous(pc->green_curve, pc->red_curve, 0.0625);
575 SPCurve *curve = sp_curve_copy(pc->red_curve);
577 /// \todo fixme:
578 SPCanvasItem *cshape = sp_canvas_bpath_new(sp_desktop_sketch(pc->desktop), curve);
579 sp_curve_unref(curve);
580 sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cshape), pc->green_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
582 pc->green_bpaths = g_slist_prepend(pc->green_bpaths, cshape);
584 pc->red_curve_is_valid = false;
585 }
586 }
589 /*
590 Local Variables:
591 mode:c++
592 c-file-style:"stroustrup"
593 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
594 indent-tabs-mode:nil
595 fill-column:99
596 End:
597 */
598 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :