1 #define INKSCAPE_CANVAS_GRID_C
3 /*
4 *
5 * Copyright (C) Johan Engelen 2006-2007 <johan@shouraizou.nl>
6 * Copyright (C) Lauris Kaplinski 2000
7 *
8 */
11 #include "sp-canvas-util.h"
12 #include "display-forward.h"
13 #include <libnr/nr-pixops.h>
14 #include "desktop-handles.h"
15 #include "helper/units.h"
16 #include "svg/svg-color.h"
17 #include "xml/node-event-vector.h"
18 #include "sp-object.h"
20 #include "sp-namedview.h"
21 #include "inkscape.h"
22 #include "desktop.h"
24 #include "../document.h"
26 #include "canvas-grid.h"
27 #include "canvas-axonomgrid.h"
29 namespace Inkscape {
31 #define DEFAULTGRIDCOLOR 0x0000FF20
32 #define DEFAULTGRIDEMPCOLOR 0x0000FF40
35 static void grid_canvasitem_class_init (GridCanvasItemClass *klass);
36 static void grid_canvasitem_init (GridCanvasItem *grid);
37 static void grid_canvasitem_destroy (GtkObject *object);
39 static void grid_canvasitem_update (SPCanvasItem *item, NR::Matrix const &affine, unsigned int flags);
40 static void grid_canvasitem_render (SPCanvasItem *item, SPCanvasBuf *buf);
42 static SPCanvasItemClass * parent_class;
44 GtkType
45 grid_canvasitem_get_type (void)
46 {
47 static GtkType grid_canvasitem_type = 0;
49 if (!grid_canvasitem_type) {
50 GtkTypeInfo grid_canvasitem_info = {
51 "GridCanvasItem",
52 sizeof (GridCanvasItem),
53 sizeof (GridCanvasItemClass),
54 (GtkClassInitFunc) grid_canvasitem_class_init,
55 (GtkObjectInitFunc) grid_canvasitem_init,
56 NULL, NULL,
57 (GtkClassInitFunc) NULL
58 };
59 grid_canvasitem_type = gtk_type_unique (sp_canvas_item_get_type (), &grid_canvasitem_info);
60 }
61 return grid_canvasitem_type;
62 }
64 static void
65 grid_canvasitem_class_init (GridCanvasItemClass *klass)
66 {
67 GtkObjectClass *object_class;
68 SPCanvasItemClass *item_class;
70 object_class = (GtkObjectClass *) klass;
71 item_class = (SPCanvasItemClass *) klass;
73 parent_class = (SPCanvasItemClass*)gtk_type_class (sp_canvas_item_get_type ());
75 object_class->destroy = grid_canvasitem_destroy;
77 item_class->update = grid_canvasitem_update;
78 item_class->render = grid_canvasitem_render;
79 }
81 static void
82 grid_canvasitem_init (GridCanvasItem *griditem)
83 {
84 griditem->grid = NULL;
85 }
87 static void
88 grid_canvasitem_destroy (GtkObject *object)
89 {
90 g_return_if_fail (object != NULL);
91 g_return_if_fail (INKSCAPE_IS_GRID_CANVASITEM (object));
93 if (GTK_OBJECT_CLASS (parent_class)->destroy)
94 (* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
95 }
97 /**
98 */
99 static void
100 grid_canvasitem_render (SPCanvasItem * item, SPCanvasBuf * buf)
101 {
102 GridCanvasItem *gridcanvasitem = INKSCAPE_GRID_CANVASITEM (item);
104 sp_canvas_prepare_buffer (buf);
106 if (gridcanvasitem->grid) gridcanvasitem->grid->Render(buf);
107 }
109 static void
110 grid_canvasitem_update (SPCanvasItem *item, NR::Matrix const &affine, unsigned int flags)
111 {
112 GridCanvasItem *gridcanvasitem = INKSCAPE_GRID_CANVASITEM (item);
114 if (parent_class->update)
115 (* parent_class->update) (item, affine, flags);
117 if (gridcanvasitem->grid) {
118 gridcanvasitem->grid->Update(affine, flags);
120 sp_canvas_request_redraw (item->canvas,
121 -1000000, -1000000,
122 1000000, 1000000);
124 item->x1 = item->y1 = -1000000;
125 item->x2 = item->y2 = 1000000;
126 }
127 }
131 // ##########################################################
132 // CanvasGrid
134 static Inkscape::XML::NodeEventVector const _repr_events = {
135 NULL, /* child_added */
136 NULL, /* child_removed */
137 CanvasGrid::on_repr_attr_changed,
138 NULL, /* content_changed */
139 NULL /* order_changed */
140 };
142 CanvasGrid::CanvasGrid(SPNamedView * nv, Inkscape::XML::Node * in_repr)
143 {
144 repr = in_repr;
145 if (repr) {
146 repr->addListener (&_repr_events, this);
147 }
149 namedview = nv;
150 canvasitems = NULL;
151 }
153 CanvasGrid::~CanvasGrid()
154 {
155 if (repr) {
156 repr->removeListenerByData (this);
157 }
159 while (canvasitems) {
160 gtk_object_destroy(GTK_OBJECT(canvasitems->data));
161 canvasitems = g_slist_remove(canvasitems, canvasitems->data);
162 }
163 }
165 /*
166 * writes an <inkscape:grid> child to repr.
167 */
168 void
169 CanvasGrid::writeNewGridToRepr(Inkscape::XML::Node * repr, const char * gridtype)
170 {
171 if (!repr) return;
172 if (!gridtype) return;
174 // first create the child xml node, then hook it to repr. This order is important, to not set off listeners to repr before the new node is complete.
176 Inkscape::XML::Document *xml_doc = sp_document_repr_doc(sp_desktop_document(SP_ACTIVE_DESKTOP));
177 Inkscape::XML::Node *newnode;
178 newnode = xml_doc->createElement("inkscape:grid");
179 newnode->setAttribute("type",gridtype);
181 repr->appendChild(newnode);
183 // FIXME: add this to history?
184 // sp_document_done(current_document, SP_VERB_DIALOG_XML_EDITOR,
185 // _("Create new element node"));
186 }
188 /*
189 * Creates a new CanvasGrid object of type gridtype
190 */
191 CanvasGrid*
192 CanvasGrid::NewGrid(SPNamedView * nv, Inkscape::XML::Node * in_repr, const char * gridtype)
193 {
194 if (!in_repr) return NULL;
195 if (!gridtype) return NULL;
197 if (!strcmp(gridtype,"xygrid")) {
198 return (CanvasGrid*) new CanvasXYGrid(nv, in_repr);
199 } else if (!strcmp(gridtype,"axonometric")) {
200 return (CanvasGrid*) new CanvasAxonomGrid(nv, in_repr);
201 }
203 return NULL;
204 }
207 /**
208 * creates a new grid canvasitem for the SPDesktop given as parameter. Keeps a link to this canvasitem in the canvasitems list.
209 */
210 GridCanvasItem *
211 CanvasGrid::createCanvasItem(SPDesktop * desktop)
212 {
213 if (!desktop) return NULL;
214 //Johan: I think for multiple desktops it is best if each has their own canvasitem, but share the same CanvasGrid object; that is what this function is for.
216 // check if there is already a canvasitem on this desktop linking to this grid
217 for (GSList *l = canvasitems; l != NULL; l = l->next) {
218 if ( sp_desktop_gridgroup(desktop) == SP_CANVAS_GROUP(SP_CANVAS_ITEM(l->data)->parent) ) {
219 return NULL;
220 }
221 }
223 GridCanvasItem * item = INKSCAPE_GRID_CANVASITEM( sp_canvas_item_new(sp_desktop_gridgroup(desktop), INKSCAPE_TYPE_GRID_CANVASITEM, NULL) );
224 item->grid = this;
225 sp_canvas_item_show(SP_CANVAS_ITEM(item));
227 gtk_object_ref(GTK_OBJECT(item)); // since we're keeping a link to this item, we need to bump up the ref count
228 canvasitems = g_slist_prepend(canvasitems, item);
230 return item;
231 }
233 void
234 CanvasGrid::on_repr_attr_changed (Inkscape::XML::Node * repr, const gchar *key, const gchar *oldval, const gchar *newval, bool is_interactive, void * data)
235 {
236 if (!data)
237 return;
239 ((CanvasGrid*) data)->onReprAttrChanged(repr, key, oldval, newval, is_interactive);
240 }
244 // ##########################################################
245 // CanvasXYGrid
248 /**
249 * "attach_all" function
250 * A DIRECT COPY-PASTE FROM DOCUMENT-PROPERTIES.CPP TO QUICKLY GET RESULTS
251 *
252 * Helper function that attachs widgets in a 3xn table. The widgets come in an
253 * array that has two entries per table row. The two entries code for four
254 * possible cases: (0,0) means insert space in first column; (0, non-0) means
255 * widget in columns 2-3; (non-0, 0) means label in columns 1-3; and
256 * (non-0, non-0) means two widgets in columns 2 and 3.
257 **/
258 #define SPACE_SIZE_X 15
259 #define SPACE_SIZE_Y 10
260 static inline void
261 attach_all (Gtk::Table &table, const Gtk::Widget *arr[], unsigned size, int start = 0)
262 {
263 for (unsigned i=0, r=start; i<size/sizeof(Gtk::Widget*); i+=2)
264 {
265 if (arr[i] && arr[i+1])
266 {
267 table.attach (const_cast<Gtk::Widget&>(*arr[i]), 1, 2, r, r+1,
268 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
269 table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 2, 3, r, r+1,
270 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
271 }
272 else
273 {
274 if (arr[i+1])
275 table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 1, 3, r, r+1,
276 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
277 else if (arr[i])
278 {
279 Gtk::Label& label = reinterpret_cast<Gtk::Label&> (const_cast<Gtk::Widget&>(*arr[i]));
280 label.set_alignment (0.0);
281 table.attach (label, 0, 3, r, r+1,
282 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
283 }
284 else
285 {
286 Gtk::HBox *space = manage (new Gtk::HBox);
287 space->set_size_request (SPACE_SIZE_X, SPACE_SIZE_Y);
288 table.attach (*space, 0, 1, r, r+1,
289 (Gtk::AttachOptions)0, (Gtk::AttachOptions)0,0,0);
290 }
291 }
292 ++r;
293 }
294 }
296 CanvasXYGrid::CanvasXYGrid (SPNamedView * nv, Inkscape::XML::Node * in_repr)
297 : CanvasGrid(nv, in_repr), table(1, 1)
298 {
299 origin[NR::X] = origin[NR::Y] = 0.0;
300 color = DEFAULTGRIDCOLOR;
301 empcolor = DEFAULTGRIDEMPCOLOR;
302 empspacing = 5;
303 spacing[NR::X] = spacing[NR::Y] = 1.0;
304 gridunit = &sp_unit_get_by_id(SP_UNIT_PX);
305 render_dotted = false;
307 snapper = new CanvasXYGridSnapper(this, namedview, 0);
309 // initialize widgets:
310 vbox.set_border_width(2);
311 table.set_spacings(2);
312 vbox.pack_start(table, false, false, 0);
314 _rumg.init (_("Grid _units:"), "units", _wr, repr);
315 _rsu_ox.init (_("_Origin X:"), _("X coordinate of grid origin"),
316 "originx", _rumg, _wr, repr);
317 _rsu_oy.init (_("O_rigin Y:"), _("Y coordinate of grid origin"),
318 "originy", _rumg, _wr, repr);
319 _rsu_sx.init (_("Spacing _X:"), _("Distance between vertical grid lines"),
320 "spacingx", _rumg, _wr, repr);
321 _rsu_sy.init (_("Spacing _Y:"), _("Distance between horizontal grid lines"),
322 "spacingy", _rumg, _wr, repr);
323 _rcp_gcol.init (_("Grid line _color:"), _("Grid line color"),
324 _("Color of grid lines"), "color", "opacity", _wr, repr);
325 _rcp_gmcol.init (_("Ma_jor grid line color:"), _("Major grid line color"),
326 _("Color of the major (highlighted) grid lines"),
327 "empcolor", "empopacity", _wr, repr);
328 _rsi.init (_("_Major grid line every:"), _("lines"), "empspacing", _wr, repr);
329 _rcb_dotted.init ( _("_Show dots instead of lines"),
330 _("If set, displays dots at gridpoints instead of gridlines"),
331 "dotted", _wr, false, repr);
333 const Gtk::Widget* widget_array[] =
334 {
335 _rumg._label, _rumg._sel,
336 0, _rsu_ox.getSU(),
337 0, _rsu_oy.getSU(),
338 0, _rsu_sx.getSU(),
339 0, _rsu_sy.getSU(),
340 _rcp_gcol._label, _rcp_gcol._cp,
341 0, 0,
342 _rcp_gmcol._label, _rcp_gmcol._cp,
343 _rsi._label, &_rsi._hbox,
344 0, _rcb_dotted._button,
345 };
347 attach_all (table, widget_array, sizeof(widget_array));
349 vbox.show();
351 if (repr) readRepr();
352 updateWidgets();
353 }
355 CanvasXYGrid::~CanvasXYGrid ()
356 {
357 if (snapper) delete snapper;
358 }
361 /* fixme: Collect all these length parsing methods and think common sane API */
363 static gboolean sp_nv_read_length(const gchar *str, guint base, gdouble *val, const SPUnit **unit)
364 {
365 if (!str) {
366 return FALSE;
367 }
369 gchar *u;
370 gdouble v = g_ascii_strtod(str, &u);
371 if (!u) {
372 return FALSE;
373 }
374 while (isspace(*u)) {
375 u += 1;
376 }
378 if (!*u) {
379 /* No unit specified - keep default */
380 *val = v;
381 return TRUE;
382 }
384 if (base & SP_UNIT_DEVICE) {
385 if (u[0] && u[1] && !isalnum(u[2]) && !strncmp(u, "px", 2)) {
386 *unit = &sp_unit_get_by_id(SP_UNIT_PX);
387 *val = v;
388 return TRUE;
389 }
390 }
392 if (base & SP_UNIT_ABSOLUTE) {
393 if (!strncmp(u, "pt", 2)) {
394 *unit = &sp_unit_get_by_id(SP_UNIT_PT);
395 } else if (!strncmp(u, "mm", 2)) {
396 *unit = &sp_unit_get_by_id(SP_UNIT_MM);
397 } else if (!strncmp(u, "cm", 2)) {
398 *unit = &sp_unit_get_by_id(SP_UNIT_CM);
399 } else if (!strncmp(u, "m", 1)) {
400 *unit = &sp_unit_get_by_id(SP_UNIT_M);
401 } else if (!strncmp(u, "in", 2)) {
402 *unit = &sp_unit_get_by_id(SP_UNIT_IN);
403 } else {
404 return FALSE;
405 }
406 *val = v;
407 return TRUE;
408 }
410 return FALSE;
411 }
413 static gboolean sp_nv_read_opacity(const gchar *str, guint32 *color)
414 {
415 if (!str) {
416 return FALSE;
417 }
419 gchar *u;
420 gdouble v = g_ascii_strtod(str, &u);
421 if (!u) {
422 return FALSE;
423 }
424 v = CLAMP(v, 0.0, 1.0);
426 *color = (*color & 0xffffff00) | (guint32) floor(v * 255.9999);
428 return TRUE;
429 }
433 void
434 CanvasXYGrid::readRepr()
435 {
436 gchar const* value;
437 if ( (value = repr->attribute("originx")) ) {
438 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::X], &gridunit);
439 origin[NR::X] = sp_units_get_pixels(origin[NR::X], *(gridunit));
440 }
441 if ( (value = repr->attribute("originy")) ) {
442 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::Y], &gridunit);
443 origin[NR::Y] = sp_units_get_pixels(origin[NR::Y], *(gridunit));
444 }
446 if ( (value = repr->attribute("spacingx")) ) {
447 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &spacing[NR::X], &gridunit);
448 spacing[NR::X] = sp_units_get_pixels(spacing[NR::X], *(gridunit));
449 }
450 if ( (value = repr->attribute("spacingy")) ) {
451 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &spacing[NR::Y], &gridunit);
452 spacing[NR::Y] = sp_units_get_pixels(spacing[NR::Y], *(gridunit));
453 }
455 if ( (value = repr->attribute("color")) ) {
456 color = (color & 0xff) | sp_svg_read_color(value, color);
457 }
459 if ( (value = repr->attribute("empcolor")) ) {
460 empcolor = (empcolor & 0xff) | sp_svg_read_color(value, empcolor);
461 }
463 if ( (value = repr->attribute("opacity")) ) {
464 sp_nv_read_opacity(value, &color);
465 }
466 if ( (value = repr->attribute("empopacity")) ) {
467 sp_nv_read_opacity(value, &empcolor);
468 }
470 if ( (value = repr->attribute("empspacing")) ) {
471 empspacing = atoi(value);
472 }
474 if ( (value = repr->attribute("dotted")) ) {
475 render_dotted = (strcmp(value,"true") == 0);
476 }
478 for (GSList *l = canvasitems; l != NULL; l = l->next) {
479 sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) );
480 }
482 return;
483 }
485 /**
486 * Called when XML node attribute changed; updates dialog widgets if change was not done by widgets themselves.
487 */
488 void
489 CanvasXYGrid::onReprAttrChanged (Inkscape::XML::Node * repr, const gchar *key, const gchar *oldval, const gchar *newval, bool is_interactive)
490 {
491 readRepr();
493 if ( ! (_wr.isUpdating()) )
494 updateWidgets();
495 }
500 Gtk::Widget &
501 CanvasXYGrid::getWidget()
502 {
503 return vbox;
504 }
507 /**
508 * Update dialog widgets from object's values.
509 */
510 void
511 CanvasXYGrid::updateWidgets()
512 {
513 if (_wr.isUpdating()) return;
515 _wr.setUpdating (true);
517 _rumg.setUnit (gridunit);
519 gdouble val;
520 val = origin[NR::X];
521 val = sp_pixels_get_units (val, *(gridunit));
522 _rsu_ox.setValue (val);
523 val = origin[NR::Y];
524 val = sp_pixels_get_units (val, *(gridunit));
525 _rsu_oy.setValue (val);
526 val = spacing[NR::X];
527 double gridx = sp_pixels_get_units (val, *(gridunit));
528 _rsu_sx.setValue (gridx);
529 val = spacing[NR::Y];
530 double gridy = sp_pixels_get_units (val, *(gridunit));
531 _rsu_sy.setValue (gridy);
533 _rcp_gcol.setRgba32 (color);
534 _rcp_gmcol.setRgba32 (empcolor);
535 _rsi.setValue (empspacing);
537 _wr.setUpdating (false);
539 return;
540 }
544 void
545 CanvasXYGrid::Update (NR::Matrix const &affine, unsigned int flags)
546 {
547 ow = origin * affine;
548 sw = spacing * affine;
549 sw -= NR::Point(affine[4], affine[5]);
551 for(int dim = 0; dim < 2; dim++) {
552 gint scaling_factor = empspacing;
554 if (scaling_factor <= 1)
555 scaling_factor = 5;
557 scaled[dim] = FALSE;
558 sw[dim] = fabs (sw[dim]);
559 while (sw[dim] < 8.0) {
560 scaled[dim] = TRUE;
561 sw[dim] *= scaling_factor;
562 /* First pass, go up to the major line spacing, then
563 keep increasing by two. */
564 scaling_factor = 2;
565 }
566 }
567 }
570 static void
571 grid_hline (SPCanvasBuf *buf, gint y, gint xs, gint xe, guint32 rgba)
572 {
573 if ((y >= buf->rect.y0) && (y < buf->rect.y1)) {
574 guint r, g, b, a;
575 gint x0, x1, x;
576 guchar *p;
577 r = NR_RGBA32_R (rgba);
578 g = NR_RGBA32_G (rgba);
579 b = NR_RGBA32_B (rgba);
580 a = NR_RGBA32_A (rgba);
581 x0 = MAX (buf->rect.x0, xs);
582 x1 = MIN (buf->rect.x1, xe + 1);
583 p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x0 - buf->rect.x0) * 3;
584 for (x = x0; x < x1; x++) {
585 p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
586 p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
587 p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
588 p += 3;
589 }
590 }
591 }
593 static void
594 grid_vline (SPCanvasBuf *buf, gint x, gint ys, gint ye, guint32 rgba)
595 {
596 if ((x >= buf->rect.x0) && (x < buf->rect.x1)) {
597 guint r, g, b, a;
598 gint y0, y1, y;
599 guchar *p;
600 r = NR_RGBA32_R(rgba);
601 g = NR_RGBA32_G (rgba);
602 b = NR_RGBA32_B (rgba);
603 a = NR_RGBA32_A (rgba);
604 y0 = MAX (buf->rect.y0, ys);
605 y1 = MIN (buf->rect.y1, ye + 1);
606 p = buf->buf + (y0 - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
607 for (y = y0; y < y1; y++) {
608 p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
609 p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
610 p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
611 p += buf->buf_rowstride;
612 }
613 }
614 }
616 static void
617 grid_dot (SPCanvasBuf *buf, gint x, gint y, guint32 rgba)
618 {
619 if ( (y >= buf->rect.y0) && (y < buf->rect.y1)
620 && (x >= buf->rect.x0) && (x < buf->rect.x1) ) {
621 guint r, g, b, a;
622 guchar *p;
623 r = NR_RGBA32_R (rgba);
624 g = NR_RGBA32_G (rgba);
625 b = NR_RGBA32_B (rgba);
626 a = NR_RGBA32_A (rgba);
627 p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
628 p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
629 p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
630 p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
631 }
632 }
634 void
635 CanvasXYGrid::Render (SPCanvasBuf *buf)
636 {
637 const gdouble sxg = floor ((buf->rect.x0 - ow[NR::X]) / sw[NR::X]) * sw[NR::X] + ow[NR::X];
638 const gint xlinestart = (gint) Inkscape::round((sxg - ow[NR::X]) / sw[NR::X]);
639 const gdouble syg = floor ((buf->rect.y0 - ow[NR::Y]) / sw[NR::Y]) * sw[NR::Y] + ow[NR::Y];
640 const gint ylinestart = (gint) Inkscape::round((syg - ow[NR::Y]) / sw[NR::Y]);
642 if (!render_dotted) {
643 gint ylinenum;
644 gdouble y;
645 for (y = syg, ylinenum = ylinestart; y < buf->rect.y1; y += sw[NR::Y], ylinenum++) {
646 const gint y0 = (gint) Inkscape::round(y);
648 if (!scaled[NR::Y] && (ylinenum % empspacing) == 0) {
649 grid_hline (buf, y0, buf->rect.x0, buf->rect.x1 - 1, empcolor);
650 } else {
651 grid_hline (buf, y0, buf->rect.x0, buf->rect.x1 - 1, color);
652 }
653 }
655 gint xlinenum;
656 gdouble x;
657 for (x = sxg, xlinenum = xlinestart; x < buf->rect.x1; x += sw[NR::X], xlinenum++) {
658 const gint ix = (gint) Inkscape::round(x);
659 if (!scaled[NR::X] && (xlinenum % empspacing) == 0) {
660 grid_vline (buf, ix, buf->rect.y0, buf->rect.y1, empcolor);
661 } else {
662 grid_vline (buf, ix, buf->rect.y0, buf->rect.y1, color);
663 }
664 }
665 } else {
666 gint ylinenum;
667 gdouble y;
668 for (y = syg, ylinenum = ylinestart; y < buf->rect.y1; y += sw[NR::Y], ylinenum++) {
669 const gint iy = (gint) Inkscape::round(y);
671 gint xlinenum;
672 gdouble x;
673 for (x = sxg, xlinenum = xlinestart; x < buf->rect.x1; x += sw[NR::X], xlinenum++) {
674 const gint ix = (gint) Inkscape::round(x);
675 if ( (!scaled[NR::X] && (xlinenum % empspacing) == 0)
676 || (!scaled[NR::Y] && (ylinenum % empspacing) == 0) )
677 {
678 grid_dot (buf, ix, iy, empcolor | (guint32)0x000000FF); // put alpha to max value
679 }
680 else
681 {
682 grid_dot (buf, ix, iy, color | (guint32)0x000000FF); // put alpha to max value
683 }
684 }
686 }
687 }
688 }
693 /**
694 * \return x rounded to the nearest multiple of c1 plus c0.
695 *
696 * \note
697 * If c1==0 (and c0 is finite), then returns +/-inf. This makes grid spacing of zero
698 * mean "ignore the grid in this dimention". We're currently discussing "good" semantics
699 * for guide/grid snapping.
700 */
702 /* FIXME: move this somewhere else, perhaps */
703 static double round_to_nearest_multiple_plus(double x, double const c1, double const c0)
704 {
705 return floor((x - c0) / c1 + .5) * c1 + c0;
706 }
708 CanvasXYGridSnapper::CanvasXYGridSnapper(CanvasXYGrid *grid, SPNamedView const *nv, NR::Coord const d) : LineSnapper(nv, d)
709 {
710 this->grid = grid;
711 }
713 LineSnapper::LineList
714 CanvasXYGridSnapper::_getSnapLines(NR::Point const &p) const
715 {
716 LineList s;
718 if ( grid == NULL ) {
719 return s;
720 }
722 for (unsigned int i = 0; i < 2; ++i) {
724 /* This is to make sure we snap to only visible grid lines */
725 double scaled_spacing = grid->sw[i]; // this is spacing of visible lines if screen pixels
727 // convert screen pixels to px
728 // FIXME: after we switch to snapping dist in screen pixels, this will be unnecessary
729 if (SP_ACTIVE_DESKTOP) {
730 scaled_spacing /= SP_ACTIVE_DESKTOP->current_zoom();
731 }
733 NR::Coord const rounded = round_to_nearest_multiple_plus(p[i],
734 scaled_spacing,
735 grid->origin[i]);
737 s.push_back(std::make_pair(NR::Dim2(i), rounded));
738 }
740 return s;
741 }
747 }; /* namespace Inkscape */
749 /*
750 Local Variables:
751 mode:c++
752 c-file-style:"stroustrup"
753 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
754 indent-tabs-mode:nil
755 fill-column:99
756 End:
757 */
758 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :