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 "selection-chemistry.h"
25 #include "draw-anchor.h"
26 #include "message-stack.h"
27 #include "message-context.h"
28 #include "modifier-fns.h"
29 #include "sp-path.h"
30 #include "prefs-utils.h"
31 #include "snap.h"
32 #include "pixmaps/cursor-pencil.xpm"
33 #include "display/bezier-utils.h"
34 #include "display/canvas-bpath.h"
35 #include "display/snap-indicator.h"
36 #include <glibmm/i18n.h>
37 #include "libnr/in-svg-plane.h"
38 #include "libnr/n-art-bpath.h"
39 #include "context-fns.h"
40 #include "sp-namedview.h"
41 #include "xml/repr.h"
42 #include "document.h"
43 #include "desktop-style.h"
44 #include "macros.h"
46 static void sp_pencil_context_class_init(SPPencilContextClass *klass);
47 static void sp_pencil_context_init(SPPencilContext *pc);
48 static void sp_pencil_context_setup(SPEventContext *ec);
49 static void sp_pencil_context_dispose(GObject *object);
51 static gint sp_pencil_context_root_handler(SPEventContext *event_context, GdkEvent *event);
52 static gint pencil_handle_button_press(SPPencilContext *const pc, GdkEventButton const &bevent);
53 static gint pencil_handle_motion_notify(SPPencilContext *const pc, GdkEventMotion const &mevent);
54 static gint pencil_handle_button_release(SPPencilContext *const pc, GdkEventButton const &revent);
55 static gint pencil_handle_key_press(SPPencilContext *const pc, guint const keyval, guint const state);
57 static void spdc_set_startpoint(SPPencilContext *pc, NR::Point const p);
58 static void spdc_set_endpoint(SPPencilContext *pc, NR::Point const p);
59 static void spdc_finish_endpoint(SPPencilContext *pc);
60 static void spdc_add_freehand_point(SPPencilContext *pc, NR::Point p, guint state);
61 static void fit_and_split(SPPencilContext *pc);
64 static SPDrawContextClass *pencil_parent_class;
66 /**
67 * Register SPPencilContext class with Gdk and return its type number.
68 */
69 GType
70 sp_pencil_context_get_type()
71 {
72 static GType type = 0;
73 if (!type) {
74 GTypeInfo info = {
75 sizeof(SPPencilContextClass),
76 NULL, NULL,
77 (GClassInitFunc) sp_pencil_context_class_init,
78 NULL, NULL,
79 sizeof(SPPencilContext),
80 4,
81 (GInstanceInitFunc) sp_pencil_context_init,
82 NULL, /* value_table */
83 };
84 type = g_type_register_static(SP_TYPE_DRAW_CONTEXT, "SPPencilContext", &info, (GTypeFlags)0);
85 }
86 return type;
87 }
89 /**
90 * Initialize SPPencilContext vtable.
91 */
92 static void
93 sp_pencil_context_class_init(SPPencilContextClass *klass)
94 {
95 GObjectClass *object_class;
96 SPEventContextClass *event_context_class;
98 object_class = (GObjectClass *) klass;
99 event_context_class = (SPEventContextClass *) klass;
101 pencil_parent_class = (SPDrawContextClass*)g_type_class_peek_parent(klass);
103 object_class->dispose = sp_pencil_context_dispose;
105 event_context_class->setup = sp_pencil_context_setup;
106 event_context_class->root_handler = sp_pencil_context_root_handler;
107 }
109 /**
110 * Callback to initialize SPPencilContext object.
111 */
112 static void
113 sp_pencil_context_init(SPPencilContext *pc)
114 {
115 SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
117 event_context->cursor_shape = cursor_pencil_xpm;
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 SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
207 if ( bevent.button == 1 && !event_context->space_panning) {
209 SPDrawContext *dc = SP_DRAW_CONTEXT (pc);
210 SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
211 Inkscape::Selection *selection = sp_desktop_selection(desktop);
213 if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
214 return TRUE;
215 }
217 NR::Point const button_w(bevent.x, bevent.y);
219 /* Find desktop coordinates */
220 NR::Point p = pc->desktop->w2d(button_w);
222 /* Test whether we hit any anchor. */
223 SPDrawAnchor *anchor = spdc_test_inside(pc, button_w);
225 switch (pc->state) {
226 case SP_PENCIL_CONTEXT_ADDLINE:
227 /* Current segment will be finished with release */
228 ret = TRUE;
229 break;
230 default:
231 /* Set first point of sequence */
232 if (bevent.state & GDK_CONTROL_MASK) {
233 freehand_create_single_dot(event_context, p, "tools.freehand.pencil", bevent.state);
234 ret = true;
235 break;
236 }
237 if (anchor) {
238 p = anchor->dp;
239 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Continuing selected path"));
240 } else {
242 if (!(bevent.state & GDK_SHIFT_MASK)) {
244 // This is the first click of a new curve; deselect item so that
245 // this curve is not combined with it (unless it is drawn from its
246 // anchor, which is handled by the sibling branch above)
247 selection->clear();
248 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Creating new path"));
249 SnapManager const &m = desktop->namedview->snap_manager;
250 p = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, p, NULL).getPoint();
251 } else if (selection->singleItem() && SP_IS_PATH(selection->singleItem())) {
252 desktop->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Appending to selected path"));
253 }
254 }
255 pc->sa = anchor;
256 spdc_set_startpoint(pc, p);
257 ret = TRUE;
258 break;
259 }
261 pc->is_drawing = true;
262 }
263 return ret;
264 }
266 static gint
267 pencil_handle_motion_notify(SPPencilContext *const pc, GdkEventMotion const &mevent)
268 {
269 if ((mevent.state & GDK_CONTROL_MASK) && (mevent.state & GDK_BUTTON1_MASK)) {
270 // mouse was accidentally moved during Ctrl+click;
271 // ignore the motion and create a single point
272 pc->is_drawing = false;
273 return TRUE;
274 }
275 gint ret = FALSE;
276 SPDesktop *const dt = pc->desktop;
278 dt->snapindicator->remove_snappoint();
280 SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
281 if (event_context->space_panning || mevent.state & GDK_BUTTON2_MASK || mevent.state & GDK_BUTTON3_MASK) {
282 // allow scrolling
283 return FALSE;
284 }
286 if ( ( mevent.state & GDK_BUTTON1_MASK ) && !pc->grab && pc->is_drawing) {
287 /* Grab mouse, so release will not pass unnoticed */
288 pc->grab = SP_CANVAS_ITEM(dt->acetate);
289 sp_canvas_item_grab(pc->grab, ( GDK_KEY_PRESS_MASK | GDK_BUTTON_PRESS_MASK |
290 GDK_BUTTON_RELEASE_MASK |
291 GDK_POINTER_MOTION_MASK ),
292 NULL, mevent.time);
293 }
295 /* Find desktop coordinates */
296 NR::Point p = dt->w2d(NR::Point(mevent.x, mevent.y));
298 /* Test whether we hit any anchor. */
299 SPDrawAnchor *anchor = spdc_test_inside(pc, NR::Point(mevent.x, mevent.y));
301 switch (pc->state) {
302 case SP_PENCIL_CONTEXT_ADDLINE:
303 /* Set red endpoint */
304 if (anchor) {
305 p = anchor->dp;
306 } else {
307 spdc_endpoint_snap(pc, p, mevent.state);
308 }
309 spdc_set_endpoint(pc, p);
310 ret = TRUE;
311 break;
312 default:
313 /* We may be idle or already freehand */
314 if ( mevent.state & GDK_BUTTON1_MASK && pc->is_drawing ) {
315 pc->state = SP_PENCIL_CONTEXT_FREEHAND;
316 if ( !pc->sa && !pc->green_anchor ) {
317 /* Create green anchor */
318 pc->green_anchor = sp_draw_anchor_new(pc, pc->green_curve, TRUE, pc->p[0]);
319 }
320 /** \todo
321 * fixme: I am not sure whether we want to snap to anchors
322 * in middle of freehand (Lauris)
323 */
324 if (anchor) {
325 p = anchor->dp;
326 } else if ((mevent.state & GDK_SHIFT_MASK) == 0) {
327 SnapManager const &m = dt->namedview->snap_manager;
328 Inkscape::SnappedPoint const s = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, p, NULL);
329 p = s.getPoint();
330 if (s.getDistance() < NR_HUGE) {
331 dt->snapindicator->set_new_snappoint(p.to_2geom());
332 }
333 }
334 if ( pc->npoints != 0 ) { // buttonpress may have happened before we entered draw context!
335 spdc_add_freehand_point(pc, p, mevent.state);
336 ret = TRUE;
337 }
339 if (anchor && !pc->anchor_statusbar) {
340 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Release</b> here to close and finish the path."));
341 pc->anchor_statusbar = true;
342 } else if (!anchor && pc->anchor_statusbar) {
343 pc->_message_context->clear();
344 pc->anchor_statusbar = false;
345 } else if (!anchor) {
346 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("Drawing a freehand path"));
347 }
349 } else {
350 if (anchor && !pc->anchor_statusbar) {
351 pc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drag</b> to continue the path from this point."));
352 pc->anchor_statusbar = true;
353 } else if (!anchor && pc->anchor_statusbar) {
354 pc->_message_context->clear();
355 pc->anchor_statusbar = false;
356 }
357 }
358 break;
359 }
360 return ret;
361 }
363 static gint
364 pencil_handle_button_release(SPPencilContext *const pc, GdkEventButton const &revent)
365 {
366 gint ret = FALSE;
368 SPEventContext *event_context = SP_EVENT_CONTEXT(pc);
369 if ( revent.button == 1 && pc->is_drawing && !event_context->space_panning) {
370 SPDesktop *const dt = pc->desktop;
372 pc->is_drawing = false;
374 /* Find desktop coordinates */
375 NR::Point p = dt->w2d(NR::Point(revent.x, revent.y));
377 /* Test whether we hit any anchor. */
378 SPDrawAnchor *anchor = spdc_test_inside(pc, NR::Point(revent.x,
379 revent.y));
381 switch (pc->state) {
382 case SP_PENCIL_CONTEXT_IDLE:
383 /* Releasing button in idle mode means single click */
384 /* We have already set up start point/anchor in button_press */
385 if (!(revent.state & GDK_CONTROL_MASK)) {
386 // Ctrl+click creates a single point so only set context in ADDLINE mode when Ctrl isn't pressed
387 pc->state = SP_PENCIL_CONTEXT_ADDLINE;
388 }
389 ret = TRUE;
390 break;
391 case SP_PENCIL_CONTEXT_ADDLINE:
392 /* Finish segment now */
393 if (anchor) {
394 p = anchor->dp;
395 } else {
396 spdc_endpoint_snap(pc, p, revent.state);
397 }
398 pc->ea = anchor;
399 spdc_set_endpoint(pc, p);
400 spdc_finish_endpoint(pc);
401 pc->state = SP_PENCIL_CONTEXT_IDLE;
402 ret = TRUE;
403 break;
404 case SP_PENCIL_CONTEXT_FREEHAND:
405 /* Finish segment now */
406 /// \todo fixme: Clean up what follows (Lauris)
407 if (anchor) {
408 p = anchor->dp;
409 }
410 pc->ea = anchor;
411 /* Write curves to object */
413 dt->messageStack()->flash(Inkscape::NORMAL_MESSAGE, _("Finishing freehand"));
415 spdc_concat_colors_and_flush(pc, FALSE);
416 pc->sa = NULL;
417 pc->ea = NULL;
418 if (pc->green_anchor) {
419 pc->green_anchor = sp_draw_anchor_destroy(pc->green_anchor);
420 }
421 pc->state = SP_PENCIL_CONTEXT_IDLE;
422 ret = TRUE;
423 break;
424 default:
425 break;
426 }
428 if (pc->grab) {
429 /* Release grab now */
430 sp_canvas_item_ungrab(pc->grab, revent.time);
431 pc->grab = NULL;
432 }
434 ret = TRUE;
435 }
436 return ret;
437 }
439 static void
440 pencil_cancel (SPPencilContext *const pc)
441 {
442 if (pc->grab) {
443 /* Release grab now */
444 sp_canvas_item_ungrab(pc->grab, 0);
445 pc->grab = NULL;
446 }
448 pc->is_drawing = false;
450 pc->state = SP_PENCIL_CONTEXT_IDLE;
452 sp_curve_reset(pc->red_curve);
453 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), NULL);
454 while (pc->green_bpaths) {
455 gtk_object_destroy(GTK_OBJECT(pc->green_bpaths->data));
456 pc->green_bpaths = g_slist_remove(pc->green_bpaths, pc->green_bpaths->data);
457 }
458 sp_curve_reset(pc->green_curve);
459 if (pc->green_anchor) {
460 pc->green_anchor = sp_draw_anchor_destroy(pc->green_anchor);
461 }
463 pc->_message_context->clear();
464 pc->_message_context->flash(Inkscape::NORMAL_MESSAGE, _("Drawing cancelled"));
466 sp_canvas_end_forced_full_redraws(pc->desktop->canvas);
467 }
470 static gint
471 pencil_handle_key_press(SPPencilContext *const pc, guint const keyval, guint const state)
472 {
473 gint ret = FALSE;
474 switch (keyval) {
475 case GDK_Up:
476 case GDK_Down:
477 case GDK_KP_Up:
478 case GDK_KP_Down:
479 // Prevent the zoom field from activation.
480 if (!mod_ctrl_only(state)) {
481 ret = TRUE;
482 }
483 break;
484 case GDK_Escape:
485 if (pc->npoints != 0) {
486 // if drawing, cancel, otherwise pass it up for deselecting
487 if (pc->is_drawing) {
488 pencil_cancel (pc);
489 ret = TRUE;
490 }
491 }
492 break;
493 case GDK_z:
494 case GDK_Z:
495 if (mod_ctrl_only(state) && pc->npoints != 0) {
496 // if drawing, cancel, otherwise pass it up for undo
497 if (pc->is_drawing) {
498 pencil_cancel (pc);
499 ret = TRUE;
500 }
501 }
502 break;
503 case GDK_g:
504 case GDK_G:
505 if (mod_shift_only(state)) {
506 sp_selection_to_guides();
507 ret = true;
508 }
509 break;
510 default:
511 break;
512 }
513 return ret;
514 }
516 /**
517 * Reset points and set new starting point.
518 */
519 static void
520 spdc_set_startpoint(SPPencilContext *const pc, NR::Point const p)
521 {
522 pc->npoints = 0;
523 pc->red_curve_is_valid = false;
524 if (in_svg_plane(p)) {
525 pc->p[pc->npoints++] = p;
526 }
527 }
529 /**
530 * Change moving endpoint position.
531 * <ul>
532 * <li>Ctrl constrains to moving to H/V direction, snapping in given direction.
533 * <li>Otherwise we snap freely to whatever attractors are available.
534 * </ul>
535 *
536 * Number of points is (re)set to 2 always, 2nd point is modified.
537 * We change RED curve.
538 */
539 static void
540 spdc_set_endpoint(SPPencilContext *const pc, NR::Point const p)
541 {
542 if (pc->npoints == 0) {
543 return;
544 /* May occur if first point wasn't in SVG plane (e.g. weird w2d transform, perhaps from bad
545 * zoom setting).
546 */
547 }
548 g_return_if_fail( pc->npoints > 0 );
550 sp_curve_reset(pc->red_curve);
551 if ( ( p == pc->p[0] )
552 || !in_svg_plane(p) )
553 {
554 pc->npoints = 1;
555 } else {
556 pc->p[1] = p;
557 pc->npoints = 2;
559 sp_curve_moveto(pc->red_curve, pc->p[0]);
560 sp_curve_lineto(pc->red_curve, pc->p[1]);
561 pc->red_curve_is_valid = true;
563 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
564 }
565 }
567 /**
568 * Finalize addline.
569 *
570 * \todo
571 * fixme: I'd like remove red reset from concat colors (lauris).
572 * Still not sure, how it will make most sense.
573 */
574 static void
575 spdc_finish_endpoint(SPPencilContext *const pc)
576 {
577 if ( ( SP_CURVE_LENGTH(pc->red_curve) != 2 )
578 || ( SP_CURVE_SEGMENT(pc->red_curve, 0)->c(3) ==
579 SP_CURVE_SEGMENT(pc->red_curve, 1)->c(3) ) )
580 {
581 sp_curve_reset(pc->red_curve);
582 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), NULL);
583 } else {
584 /* Write curves to object. */
585 spdc_concat_colors_and_flush(pc, FALSE);
586 pc->sa = NULL;
587 pc->ea = NULL;
588 }
589 }
591 static void
592 spdc_add_freehand_point(SPPencilContext *pc, NR::Point p, guint /*state*/)
593 {
594 g_assert( pc->npoints > 0 );
595 g_return_if_fail(unsigned(pc->npoints) < G_N_ELEMENTS(pc->p));
597 if ( ( p != pc->p[ pc->npoints - 1 ] )
598 && in_svg_plane(p) )
599 {
600 pc->p[pc->npoints++] = p;
601 fit_and_split(pc);
602 }
603 }
605 static inline double
606 square(double const x)
607 {
608 return x * x;
609 }
611 static void
612 fit_and_split(SPPencilContext *pc)
613 {
614 g_assert( pc->npoints > 1 );
616 double const tolerance_sq = square( NR::expansion(pc->desktop->w2d())
617 * prefs_get_double_attribute_limited("tools.freehand.pencil",
618 "tolerance", 10.0, 1.0, 100.0) );
620 NR::Point b[4];
621 g_assert(is_zero(pc->req_tangent)
622 || is_unit_vector(pc->req_tangent));
623 NR::Point const tHatEnd(0, 0);
624 int const n_segs = sp_bezier_fit_cubic_full(b, NULL, pc->p, pc->npoints,
625 pc->req_tangent, tHatEnd, tolerance_sq, 1);
626 if ( n_segs > 0
627 && unsigned(pc->npoints) < G_N_ELEMENTS(pc->p) )
628 {
629 /* Fit and draw and reset state */
630 sp_curve_reset(pc->red_curve);
631 sp_curve_moveto(pc->red_curve, b[0]);
632 sp_curve_curveto(pc->red_curve, b[1], b[2], b[3]);
633 sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(pc->red_bpath), pc->red_curve);
634 pc->red_curve_is_valid = true;
635 } else {
636 /* Fit and draw and copy last point */
638 g_assert(!sp_curve_empty(pc->red_curve));
640 /* Set up direction of next curve. */
641 {
642 NArtBpath const &last_seg = *sp_curve_last_bpath(pc->red_curve);
643 pc->p[0] = last_seg.c(3);
644 pc->npoints = 1;
645 g_assert( last_seg.code == NR_CURVETO );
646 /* Relevance: validity of last_seg.c(2). */
647 NR::Point const req_vec( pc->p[0] - last_seg.c(2) );
648 pc->req_tangent = ( ( NR::is_zero(req_vec) || !in_svg_plane(req_vec) )
649 ? NR::Point(0, 0)
650 : NR::unit_vector(req_vec) );
651 }
653 sp_curve_append_continuous(pc->green_curve, pc->red_curve, 0.0625);
654 SPCurve *curve = sp_curve_copy(pc->red_curve);
656 /// \todo fixme:
657 SPCanvasItem *cshape = sp_canvas_bpath_new(sp_desktop_sketch(pc->desktop), curve);
658 sp_curve_unref(curve);
659 sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cshape), pc->green_color, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);
661 pc->green_bpaths = g_slist_prepend(pc->green_bpaths, cshape);
663 pc->red_curve_is_valid = false;
664 }
665 }
668 /*
669 Local Variables:
670 mode:c++
671 c-file-style:"stroustrup"
672 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
673 indent-tabs-mode:nil
674 fill-column:99
675 End:
676 */
677 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :