1 #define CANVAS_AXONOMGRID_C
3 /*
4 * Copyright (C) 2006-2008 Johan Engelen <johan@shouraizou.nl>
5 */
7 /*
8 * Current limits are: one axis (y-axis) is always vertical. The other two
9 * axes are bound to a certain range of angles. The z-axis always has an angle
10 * smaller than 90 degrees (measured from horizontal, 0 degrees being a line extending
11 * to the right). The x-axis will always have an angle between 0 and 90 degrees.
12 */
14 /*
15 * TODO:
16 * THIS FILE AND THE HEADER FILE NEED CLEANING UP. PLEASE DO NOT HESISTATE TO DO SO.
17 * For example: the line drawing code should not be here. There _must_ be a function somewhere else that can provide this functionality...
18 */
20 #include "sp-canvas-util.h"
21 #include "canvas-axonomgrid.h"
22 #include "util/mathfns.h"
23 #include "2geom/geom.h"
24 #include "display-forward.h"
25 #include <libnr/nr-pixops.h>
27 #include "canvas-grid.h"
28 #include "desktop-handles.h"
29 #include "helper/units.h"
30 #include "svg/svg-color.h"
31 #include "xml/node-event-vector.h"
32 #include "sp-object.h"
34 #include "sp-namedview.h"
35 #include "inkscape.h"
36 #include "desktop.h"
38 #include "document.h"
39 #include "prefs-utils.h"
41 #define SAFE_SETPIXEL //undefine this when it is certain that setpixel is never called with invalid params
43 enum Dim3 { X=0, Y, Z };
45 #ifndef M_PI
46 # define M_PI 3.14159265358979323846
47 #endif
49 static double deg_to_rad(double deg) { return deg*M_PI/180.0;}
52 /**
53 \brief This function renders a pixel on a particular buffer.
55 The topleft of the buffer equals
56 ( rect.x0 , rect.y0 ) in screen coordinates
57 ( 0 , 0 ) in setpixel coordinates
58 The bottomright of the buffer equals
59 ( rect.x1 , rect,y1 ) in screen coordinates
60 ( rect.x1 - rect.x0 , rect.y1 - rect.y0 ) in setpixel coordinates
61 */
62 static void
63 sp_caxonomgrid_setpixel (SPCanvasBuf *buf, gint x, gint y, guint32 rgba)
64 {
65 #ifdef SAFE_SETPIXEL
66 if ( (x >= buf->rect.x0) && (x < buf->rect.x1) && (y >= buf->rect.y0) && (y < buf->rect.y1) ) {
67 #endif
68 guint r, g, b, a;
69 r = NR_RGBA32_R (rgba);
70 g = NR_RGBA32_G (rgba);
71 b = NR_RGBA32_B (rgba);
72 a = NR_RGBA32_A (rgba);
73 guchar * p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 4;
74 p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
75 p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
76 p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
77 #ifdef SAFE_SETPIXEL
78 }
79 #endif
80 }
82 /**
83 \brief This function renders a line on a particular canvas buffer,
84 using Bresenham's line drawing function.
85 http://www.cs.unc.edu/~mcmillan/comp136/Lecture6/Lines.html
86 Coordinates are interpreted as SCREENcoordinates
87 */
88 static void
89 sp_caxonomgrid_drawline (SPCanvasBuf *buf, gint x0, gint y0, gint x1, gint y1, guint32 rgba)
90 {
91 int dy = y1 - y0;
92 int dx = x1 - x0;
93 int stepx, stepy;
95 if (dy < 0) { dy = -dy; stepy = -1; } else { stepy = 1; }
96 if (dx < 0) { dx = -dx; stepx = -1; } else { stepx = 1; }
97 dy <<= 1; // dy is now 2*dy
98 dx <<= 1; // dx is now 2*dx
100 sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
101 if (dx > dy) {
102 int fraction = dy - (dx >> 1); // same as 2*dy - dx
103 while (x0 != x1) {
104 if (fraction >= 0) {
105 y0 += stepy;
106 fraction -= dx; // same as fraction -= 2*dx
107 }
108 x0 += stepx;
109 fraction += dy; // same as fraction -= 2*dy
110 sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
111 }
112 } else {
113 int fraction = dx - (dy >> 1);
114 while (y0 != y1) {
115 if (fraction >= 0) {
116 x0 += stepx;
117 fraction -= dy;
118 }
119 y0 += stepy;
120 fraction += dx;
121 sp_caxonomgrid_setpixel(buf, x0, y0, rgba);
122 }
123 }
125 }
127 static void
128 sp_grid_vline (SPCanvasBuf *buf, gint x, gint ys, gint ye, guint32 rgba)
129 {
130 if ((x >= buf->rect.x0) && (x < buf->rect.x1)) {
131 guint r, g, b, a;
132 gint y0, y1, y;
133 guchar *p;
134 r = NR_RGBA32_R(rgba);
135 g = NR_RGBA32_G (rgba);
136 b = NR_RGBA32_B (rgba);
137 a = NR_RGBA32_A (rgba);
138 y0 = MAX (buf->rect.y0, ys);
139 y1 = MIN (buf->rect.y1, ye + 1);
140 p = buf->buf + (y0 - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 4;
141 for (y = y0; y < y1; y++) {
142 p[0] = NR_COMPOSEN11_1111 (r, a, p[0]);
143 p[1] = NR_COMPOSEN11_1111 (g, a, p[1]);
144 p[2] = NR_COMPOSEN11_1111 (b, a, p[2]);
145 p += buf->buf_rowstride;
146 }
147 }
148 }
150 namespace Inkscape {
153 /**
154 * A DIRECT COPY-PASTE FROM DOCUMENT-PROPERTIES.CPP TO QUICKLY GET RESULTS
155 *
156 * Helper function that attachs widgets in a 3xn table. The widgets come in an
157 * array that has two entries per table row. The two entries code for four
158 * possible cases: (0,0) means insert space in first column; (0, non-0) means
159 * widget in columns 2-3; (non-0, 0) means label in columns 1-3; and
160 * (non-0, non-0) means two widgets in columns 2 and 3.
161 **/
162 #define SPACE_SIZE_X 15
163 #define SPACE_SIZE_Y 10
164 static inline void
165 attach_all(Gtk::Table &table, Gtk::Widget const *const arr[], unsigned size, int start = 0)
166 {
167 for (unsigned i=0, r=start; i<size/sizeof(Gtk::Widget*); i+=2) {
168 if (arr[i] && arr[i+1]) {
169 table.attach (const_cast<Gtk::Widget&>(*arr[i]), 1, 2, r, r+1,
170 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
171 table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 2, 3, r, r+1,
172 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
173 } else {
174 if (arr[i+1]) {
175 table.attach (const_cast<Gtk::Widget&>(*arr[i+1]), 1, 3, r, r+1,
176 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
177 } else if (arr[i]) {
178 Gtk::Label& label = reinterpret_cast<Gtk::Label&> (const_cast<Gtk::Widget&>(*arr[i]));
179 label.set_alignment (0.0);
180 table.attach (label, 0, 3, r, r+1,
181 Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0);
182 } else {
183 Gtk::HBox *space = manage (new Gtk::HBox);
184 space->set_size_request (SPACE_SIZE_X, SPACE_SIZE_Y);
185 table.attach (*space, 0, 1, r, r+1,
186 (Gtk::AttachOptions)0, (Gtk::AttachOptions)0,0,0);
187 }
188 }
189 ++r;
190 }
191 }
193 CanvasAxonomGrid::CanvasAxonomGrid (SPNamedView * nv, Inkscape::XML::Node * in_repr, SPDocument * in_doc)
194 : CanvasGrid(nv, in_repr, in_doc, GRID_AXONOMETRIC)
195 {
196 gridunit = sp_unit_get_by_abbreviation( prefs_get_string_attribute("options.grids.axonom", "units") );
197 if (!gridunit)
198 gridunit = &sp_unit_get_by_id(SP_UNIT_PX);
199 origin[NR::X] = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "origin_x", 0.0), *(gridunit) );
200 origin[NR::Y] = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "origin_y", 0.0), *(gridunit) );
201 color = prefs_get_int_attribute("options.grids.axonom", "color", 0x0000ff20);
202 empcolor = prefs_get_int_attribute("options.grids.axonom", "empcolor", 0x0000ff40);
203 empspacing = prefs_get_int_attribute("options.grids.axonom", "empspacing", 5);
204 lengthy = sp_units_get_pixels( prefs_get_double_attribute ("options.grids.axonom", "spacing_y", 1.0), *(gridunit) );
205 angle_deg[X] = prefs_get_double_attribute ("options.grids.axonom", "angle_x", 30.0);
206 angle_deg[Z] = prefs_get_double_attribute ("options.grids.axonom", "angle_z", 30.0);
207 angle_deg[Y] = 0;
209 angle_rad[X] = deg_to_rad(angle_deg[X]);
210 tan_angle[X] = tan(angle_rad[X]);
211 angle_rad[Z] = deg_to_rad(angle_deg[Z]);
212 tan_angle[Z] = tan(angle_rad[Z]);
214 snapper = new CanvasAxonomGridSnapper(this, namedview, 0);
216 if (repr) readRepr();
217 }
219 CanvasAxonomGrid::~CanvasAxonomGrid ()
220 {
221 if (snapper) delete snapper;
222 }
225 /* fixme: Collect all these length parsing methods and think common sane API */
227 static gboolean sp_nv_read_length(gchar const *str, guint base, gdouble *val, SPUnit const **unit)
228 {
229 if (!str) {
230 return FALSE;
231 }
233 gchar *u;
234 gdouble v = g_ascii_strtod(str, &u);
235 if (!u) {
236 return FALSE;
237 }
238 while (isspace(*u)) {
239 u += 1;
240 }
242 if (!*u) {
243 /* No unit specified - keep default */
244 *val = v;
245 return TRUE;
246 }
248 if (base & SP_UNIT_DEVICE) {
249 if (u[0] && u[1] && !isalnum(u[2]) && !strncmp(u, "px", 2)) {
250 *unit = &sp_unit_get_by_id(SP_UNIT_PX);
251 *val = v;
252 return TRUE;
253 }
254 }
256 if (base & SP_UNIT_ABSOLUTE) {
257 if (!strncmp(u, "pt", 2)) {
258 *unit = &sp_unit_get_by_id(SP_UNIT_PT);
259 } else if (!strncmp(u, "mm", 2)) {
260 *unit = &sp_unit_get_by_id(SP_UNIT_MM);
261 } else if (!strncmp(u, "cm", 2)) {
262 *unit = &sp_unit_get_by_id(SP_UNIT_CM);
263 } else if (!strncmp(u, "m", 1)) {
264 *unit = &sp_unit_get_by_id(SP_UNIT_M);
265 } else if (!strncmp(u, "in", 2)) {
266 *unit = &sp_unit_get_by_id(SP_UNIT_IN);
267 } else {
268 return FALSE;
269 }
270 *val = v;
271 return TRUE;
272 }
274 return FALSE;
275 }
277 static gboolean sp_nv_read_opacity(gchar const *str, guint32 *color)
278 {
279 if (!str) {
280 return FALSE;
281 }
283 gchar *u;
284 gdouble v = g_ascii_strtod(str, &u);
285 if (!u) {
286 return FALSE;
287 }
288 v = CLAMP(v, 0.0, 1.0);
290 *color = (*color & 0xffffff00) | (guint32) floor(v * 255.9999);
292 return TRUE;
293 }
297 void
298 CanvasAxonomGrid::readRepr()
299 {
300 gchar const *value;
301 if ( (value = repr->attribute("originx")) ) {
302 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::X], &gridunit);
303 origin[NR::X] = sp_units_get_pixels(origin[NR::X], *(gridunit));
304 }
305 if ( (value = repr->attribute("originy")) ) {
306 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::Y], &gridunit);
307 origin[NR::Y] = sp_units_get_pixels(origin[NR::Y], *(gridunit));
308 }
310 if ( (value = repr->attribute("spacingy")) ) {
311 sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &lengthy, &gridunit);
312 lengthy = sp_units_get_pixels(lengthy, *(gridunit));
313 if (lengthy < 1.0) lengthy = 1.0;
314 }
316 if ( (value = repr->attribute("gridanglex")) ) {
317 angle_deg[X] = g_ascii_strtod(value, NULL);
318 if (angle_deg[X] < 1.0) angle_deg[X] = 1.0;
319 if (angle_deg[X] > 89.0) angle_deg[X] = 89.0;
320 angle_rad[X] = deg_to_rad(angle_deg[X]);
321 tan_angle[X] = tan(angle_rad[X]);
322 }
324 if ( (value = repr->attribute("gridanglez")) ) {
325 angle_deg[Z] = g_ascii_strtod(value, NULL);
326 if (angle_deg[Z] < 1.0) angle_deg[Z] = 1.0;
327 if (angle_deg[Z] > 89.0) angle_deg[Z] = 89.0;
328 angle_rad[Z] = deg_to_rad(angle_deg[Z]);
329 tan_angle[Z] = tan(angle_rad[Z]);
330 }
332 if ( (value = repr->attribute("color")) ) {
333 color = (color & 0xff) | sp_svg_read_color(value, color);
334 }
336 if ( (value = repr->attribute("empcolor")) ) {
337 empcolor = (empcolor & 0xff) | sp_svg_read_color(value, empcolor);
338 }
340 if ( (value = repr->attribute("opacity")) ) {
341 sp_nv_read_opacity(value, &color);
342 }
343 if ( (value = repr->attribute("empopacity")) ) {
344 sp_nv_read_opacity(value, &empcolor);
345 }
347 if ( (value = repr->attribute("empspacing")) ) {
348 empspacing = atoi(value);
349 }
351 if ( (value = repr->attribute("visible")) ) {
352 visible = (strcmp(value,"true") == 0);
353 }
355 if ( (value = repr->attribute("enabled")) ) {
356 g_assert(snapper != NULL);
357 snapper->setEnabled(strcmp(value,"true") == 0);
358 }
360 for (GSList *l = canvasitems; l != NULL; l = l->next) {
361 sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) );
362 }
363 return;
364 }
366 /**
367 * Called when XML node attribute changed; updates dialog widgets if change was not done by widgets themselves.
368 */
369 void
370 CanvasAxonomGrid::onReprAttrChanged(Inkscape::XML::Node */*repr*/, gchar const */*key*/, gchar const */*oldval*/, gchar const */*newval*/, bool /*is_interactive*/)
371 {
372 readRepr();
374 if ( ! (_wr.isUpdating()) )
375 updateWidgets();
376 }
381 Gtk::Widget *
382 CanvasAxonomGrid::newSpecificWidget()
383 {
384 Gtk::Table * table = Gtk::manage( new Gtk::Table(1,1) );
385 table->set_spacings(2);
387 _wr.setUpdating (true);
389 Inkscape::UI::Widget::RegisteredUnitMenu *_rumg = Gtk::manage( new Inkscape::UI::Widget::RegisteredUnitMenu(
390 _("Grid _units:"), "units", _wr, repr, doc) );
391 Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_ox = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
392 _("_Origin X:"), _("X coordinate of grid origin"), "originx", *_rumg, _wr, repr, doc) );
393 Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_oy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
394 _("O_rigin Y:"), _("Y coordinate of grid origin"), "originy", *_rumg, _wr, repr, doc) );
395 Inkscape::UI::Widget::RegisteredScalarUnit *_rsu_sy = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalarUnit(
396 _("Spacing _Y:"), _("Base length of z-axis"), "spacingy", *_rumg, _wr, repr, doc) );
397 Inkscape::UI::Widget::RegisteredScalar *_rsu_ax = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalar(
398 _("Angle X:"), _("Angle of x-axis"), "gridanglex", _wr, repr, doc ) );
399 Inkscape::UI::Widget::RegisteredScalar *_rsu_az = Gtk::manage( new Inkscape::UI::Widget::RegisteredScalar(
400 _("Angle Z:"), _("Angle of z-axis"), "gridanglez", _wr, repr, doc ) );
402 Inkscape::UI::Widget::RegisteredColorPicker *_rcp_gcol = Gtk::manage(
403 new Inkscape::UI::Widget::RegisteredColorPicker(
404 _("Grid line _color:"), _("Grid line color"), _("Color of grid lines"),
405 "color", "opacity", _wr, repr, doc));
407 Inkscape::UI::Widget::RegisteredColorPicker *_rcp_gmcol = Gtk::manage(
408 new Inkscape::UI::Widget::RegisteredColorPicker(
409 _("Ma_jor grid line color:"), _("Major grid line color"),
410 _("Color of the major (highlighted) grid lines"),
411 "empcolor", "empopacity", _wr, repr, doc));
413 Inkscape::UI::Widget::RegisteredSuffixedInteger *_rsi = Gtk::manage( new Inkscape::UI::Widget::RegisteredSuffixedInteger(
414 _("_Major grid line every:"), "", _("lines"), "empspacing", _wr, repr, doc ) );
416 _rsu_ox->setDigits(4);
417 _rsu_ox->setIncrements(0.1, 1.0);
419 _rsu_oy->setDigits(4);
420 _rsu_oy->setIncrements(0.1, 1.0);
422 _rsu_sy->setDigits(4);
423 _rsu_sy->setIncrements(0.1, 1.0);
425 _wr.setUpdating (false);
427 Gtk::Widget const *const widget_array[] = {
428 0, _rumg,
429 0, _rsu_ox,
430 0, _rsu_oy,
431 0, _rsu_sy,
432 0, _rsu_ax,
433 0, _rsu_az,
434 _rcp_gcol->_label, _rcp_gcol,
435 0, 0,
436 _rcp_gmcol->_label, _rcp_gmcol,
437 0, _rsi,
438 };
440 attach_all (*table, widget_array, sizeof(widget_array));
442 // set widget values
443 _rumg->setUnit (gridunit);
445 gdouble val;
446 val = origin[NR::X];
447 val = sp_pixels_get_units (val, *(gridunit));
448 _rsu_ox->setValue (val);
449 val = origin[NR::Y];
450 val = sp_pixels_get_units (val, *(gridunit));
451 _rsu_oy->setValue (val);
452 val = lengthy;
453 double gridy = sp_pixels_get_units (val, *(gridunit));
454 _rsu_sy->setValue (gridy);
456 _rsu_ax->setValue(angle_deg[X]);
457 _rsu_az->setValue(angle_deg[Z]);
459 _rcp_gcol->setRgba32 (color);
460 _rcp_gmcol->setRgba32 (empcolor);
461 _rsi->setValue (empspacing);
463 return table;
464 }
467 /**
468 * Update dialog widgets from object's values.
469 */
470 void
471 CanvasAxonomGrid::updateWidgets()
472 {
473 /* if (_wr.isUpdating()) return;
475 _wr.setUpdating (true);
477 _rcb_visible.setActive(visible);
478 if (snapper != NULL) {
479 _rcb_enabled.setActive(snapper->getEnabled());
480 }
482 _rumg.setUnit (gridunit);
484 gdouble val;
485 val = origin[NR::X];
486 val = sp_pixels_get_units (val, *(gridunit));
487 _rsu_ox.setValue (val);
488 val = origin[NR::Y];
489 val = sp_pixels_get_units (val, *(gridunit));
490 _rsu_oy.setValue (val);
491 val = lengthy;
492 double gridy = sp_pixels_get_units (val, *(gridunit));
493 _rsu_sy.setValue (gridy);
495 _rsu_ax.setValue(angle_deg[X]);
496 _rsu_az.setValue(angle_deg[Z]);
498 _rcp_gcol.setRgba32 (color);
499 _rcp_gmcol.setRgba32 (empcolor);
500 _rsi.setValue (empspacing);
502 _wr.setUpdating (false);
504 return;
505 */
506 }
510 void
511 CanvasAxonomGrid::Update (NR::Matrix const &affine, unsigned int /*flags*/)
512 {
513 ow = origin * affine;
514 sw = NR::Point(fabs(affine[0]),fabs(affine[3]));
516 for(int dim = 0; dim < 2; dim++) {
517 gint scaling_factor = empspacing;
519 if (scaling_factor <= 1)
520 scaling_factor = 5;
522 scaled = FALSE;
523 int watchdog = 0;
524 while ( (sw[dim] < 8.0) & (watchdog < 100) ) {
525 scaled = TRUE;
526 sw[dim] *= scaling_factor;
527 // First pass, go up to the major line spacing, then
528 // keep increasing by two.
529 scaling_factor = 2;
530 watchdog++;
531 }
533 }
535 spacing_ylines = sw[NR::X] * lengthy /(tan_angle[X] + tan_angle[Z]);
536 lyw = sw[NR::Y] * lengthy;
537 lxw_x = (lengthy / tan_angle[X]) * sw[NR::X];
538 lxw_z = (lengthy / tan_angle[Z]) * sw[NR::X];
540 if (empspacing == 0) {
541 scaled = TRUE;
542 }
544 }
546 void
547 CanvasAxonomGrid::Render (SPCanvasBuf *buf)
548 {
549 //set correct coloring, depending preference (when zoomed out, always major coloring or minor coloring)
550 guint32 _empcolor;
551 bool preference = prefs_get_int_attribute ("options.grids", "no_emphasize_when_zoomedout", 0) == 1;
552 if( scaled && preference ) {
553 _empcolor = color;
554 } else {
555 _empcolor = empcolor;
556 }
558 // gc = gridcoordinates (the coordinates calculated from the grids origin 'grid->ow'.
559 // sc = screencoordinates ( for example "buf->rect.x0" is in screencoordinates )
560 // bc = buffer patch coordinates
562 // tl = topleft ; br = bottomright
563 NR::Point buf_tl_gc;
564 NR::Point buf_br_gc;
565 buf_tl_gc[NR::X] = buf->rect.x0 - ow[NR::X];
566 buf_tl_gc[NR::Y] = buf->rect.y0 - ow[NR::Y];
567 buf_br_gc[NR::X] = buf->rect.x1 - ow[NR::X];
568 buf_br_gc[NR::Y] = buf->rect.y1 - ow[NR::Y];
570 gdouble x;
571 gdouble y;
573 // render the three separate line groups representing the main-axes
575 // x-axis always goes from topleft to bottomright. (0,0) - (1,1)
576 gdouble const xintercept_y_bc = (buf_tl_gc[NR::X] * tan_angle[X]) - buf_tl_gc[NR::Y] ;
577 gdouble const xstart_y_sc = ( xintercept_y_bc - floor(xintercept_y_bc/lyw)*lyw ) + buf->rect.y0;
578 gint const xlinestart = (gint) Inkscape::round( (xstart_y_sc - buf->rect.x0*tan_angle[X] -ow[NR::Y]) / lyw );
579 gint xlinenum = xlinestart;
580 // lines starting on left side.
581 for (y = xstart_y_sc; y < buf->rect.y1; y += lyw, xlinenum++) {
582 gint const x0 = buf->rect.x0;
583 gint const y0 = (gint) Inkscape::round(y);
584 gint const x1 = x0 + (gint) Inkscape::round( (buf->rect.y1 - y) / tan_angle[X] );
585 gint const y1 = buf->rect.y1;
587 if (!scaled && (xlinenum % empspacing) != 0) {
588 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
589 } else {
590 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, _empcolor);
591 }
592 }
593 // lines starting from top side
594 gdouble const xstart_x_sc = buf->rect.x0 + (lxw_x - (xstart_y_sc - buf->rect.y0) / tan_angle[X]) ;
595 xlinenum = xlinestart-1;
596 for (x = xstart_x_sc; x < buf->rect.x1; x += lxw_x, xlinenum--) {
597 gint const y0 = buf->rect.y0;
598 gint const y1 = buf->rect.y1;
599 gint const x0 = (gint) Inkscape::round(x);
600 gint const x1 = x0 + (gint) Inkscape::round( (y1 - y0) / tan_angle[X] );
602 if (!scaled && (xlinenum % empspacing) != 0) {
603 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
604 } else {
605 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, _empcolor);
606 }
607 }
609 // y-axis lines (vertical)
610 gdouble const ystart_x_sc = floor (buf_tl_gc[NR::X] / spacing_ylines) * spacing_ylines + ow[NR::X];
611 gint const ylinestart = (gint) Inkscape::round((ystart_x_sc - ow[NR::X]) / spacing_ylines);
612 gint ylinenum = ylinestart;
613 for (x = ystart_x_sc; x < buf->rect.x1; x += spacing_ylines, ylinenum++) {
614 gint const x0 = (gint) Inkscape::round(x);
616 if (!scaled && (ylinenum % empspacing) != 0) {
617 sp_grid_vline (buf, x0, buf->rect.y0, buf->rect.y1 - 1, color);
618 } else {
619 sp_grid_vline (buf, x0, buf->rect.y0, buf->rect.y1 - 1, _empcolor);
620 }
621 }
623 // z-axis always goes from bottomleft to topright. (0,1) - (1,0)
624 gdouble const zintercept_y_bc = (buf_tl_gc[NR::X] * -tan_angle[Z]) - buf_tl_gc[NR::Y] ;
625 gdouble const zstart_y_sc = ( zintercept_y_bc - floor(zintercept_y_bc/lyw)*lyw ) + buf->rect.y0;
626 gint const zlinestart = (gint) Inkscape::round( (zstart_y_sc + buf->rect.x0*tan_angle[Z] - ow[NR::Y]) / lyw );
627 gint zlinenum = zlinestart;
628 // lines starting from left side
629 for (y = zstart_y_sc; y < buf->rect.y1; y += lyw, zlinenum++) {
630 gint const x0 = buf->rect.x0;
631 gint const y0 = (gint) Inkscape::round(y);
632 gint const x1 = x0 + (gint) Inkscape::round( (y - buf->rect.y0 ) / tan_angle[Z] );
633 gint const y1 = buf->rect.y0;
635 if (!scaled && (zlinenum % empspacing) != 0) {
636 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
637 } else {
638 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, _empcolor);
639 }
640 }
641 // draw lines from bottom-up
642 gdouble const zstart_x_sc = buf->rect.x0 + (y - buf->rect.y1) / tan_angle[Z] ;
643 for (x = zstart_x_sc; x < buf->rect.x1; x += lxw_z, zlinenum++) {
644 gint const y0 = buf->rect.y1;
645 gint const y1 = buf->rect.y0;
646 gint const x0 = (gint) Inkscape::round(x);
647 gint const x1 = x0 + (gint) Inkscape::round( (buf->rect.y1 - buf->rect.y0) / tan_angle[Z] );
649 if (!scaled && (zlinenum % empspacing) != 0) {
650 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, color);
651 } else {
652 sp_caxonomgrid_drawline (buf, x0, y0, x1, y1, _empcolor);
653 }
654 }
655 }
657 CanvasAxonomGridSnapper::CanvasAxonomGridSnapper(CanvasAxonomGrid *grid, SPNamedView const *nv, NR::Coord const d) : LineSnapper(nv, d)
658 {
659 this->grid = grid;
660 }
662 LineSnapper::LineList
663 CanvasAxonomGridSnapper::_getSnapLines(NR::Point const &p) const
664 {
665 LineList s;
667 if ( grid == NULL ) {
668 return s;
669 }
671 /* This is to make sure we snap to only visible grid lines */
672 double scaled_spacing_h = grid->spacing_ylines; // this is spacing of visible lines if screen pixels
673 double scaled_spacing_v = grid->lyw; // vertical
675 // convert screen pixels to px
676 // FIXME: after we switch to snapping dist in screen pixels, this will be unnecessary
677 if (SP_ACTIVE_DESKTOP) {
678 scaled_spacing_h /= SP_ACTIVE_DESKTOP->current_zoom();
679 scaled_spacing_v /= SP_ACTIVE_DESKTOP->current_zoom();
680 }
682 // In an axonometric grid, any point will be surrounded by 6 grid lines:
683 // - 2 vertical grid lines, one left and one right from the point
684 // - 2 angled z grid lines, one above and one below the point
685 // - 2 angled x grid lines, one above and one below the point
687 // Calculate the x coordinate of the vertical grid lines
688 NR::Coord x_max = Inkscape::Util::round_to_upper_multiple_plus(p[NR::X], scaled_spacing_h, grid->origin[NR::X]);
689 NR::Coord x_min = Inkscape::Util::round_to_lower_multiple_plus(p[NR::X], scaled_spacing_h, grid->origin[NR::X]);
691 // Calculate the y coordinate of the intersection of the angled grid lines with the y-axis
692 double y_proj_along_z = p[NR::Y] - grid->tan_angle[Z]*(p[NR::X] - grid->origin[NR::X]);
693 double y_proj_along_x = p[NR::Y] + grid->tan_angle[X]*(p[NR::X] - grid->origin[NR::X]);
694 double y_proj_along_z_max = Inkscape::Util::round_to_upper_multiple_plus(y_proj_along_z, scaled_spacing_v, grid->origin[NR::Y]);
695 double y_proj_along_z_min = Inkscape::Util::round_to_lower_multiple_plus(y_proj_along_z, scaled_spacing_v, grid->origin[NR::Y]);
696 double y_proj_along_x_max = Inkscape::Util::round_to_upper_multiple_plus(y_proj_along_x, scaled_spacing_v, grid->origin[NR::Y]);
697 double y_proj_along_x_min = Inkscape::Util::round_to_lower_multiple_plus(y_proj_along_x, scaled_spacing_v, grid->origin[NR::Y]);
699 // Calculate the normal for the angled grid lines
700 NR::Point norm_x = NR::rot90(NR::Point(1, -grid->tan_angle[X]));
701 NR::Point norm_z = NR::rot90(NR::Point(1, grid->tan_angle[Z]));
703 // The four angled grid lines form a parallellogram, enclosing the point
704 // One of the two vertical grid lines divides this parallellogram in two triangles
705 // We will now try to find out in which half (i.e. triangle) our point is, and return
706 // only the three grid lines defining that triangle
708 // The vertical grid line is at the intersection of two angled grid lines.
709 // Now go find that intersection!
710 Geom::Point result;
711 Geom::IntersectorKind is = line_intersection(norm_x.to_2geom(), norm_x[NR::Y]*y_proj_along_x_max,
712 norm_z.to_2geom(), norm_z[NR::Y]*y_proj_along_z_max,
713 result);
715 // Determine which half of the parallellogram to use
716 bool use_left_half = true;
717 bool use_right_half = true;
719 if (is == Geom::intersects) {
720 use_left_half = (p[NR::X] - grid->origin[NR::X]) < result[Geom::X];
721 use_right_half = !use_left_half;
722 }
724 //std::cout << "intersection at " << result << " leads to use_left_half = " << use_left_half << " and use_right_half = " << use_right_half << std::endl;
726 // Return the three grid lines which define the triangle that encloses our point
727 // If we didn't find an intersection above, all 6 grid lines will be returned
728 if (use_left_half) {
729 s.push_back(std::make_pair(norm_z, NR::Point(grid->origin[NR::X], y_proj_along_z_max)));
730 s.push_back(std::make_pair(norm_x, NR::Point(grid->origin[NR::X], y_proj_along_x_min)));
731 s.push_back(std::make_pair(component_vectors[NR::X], NR::Point(x_max, 0)));
732 }
734 if (use_right_half) {
735 s.push_back(std::make_pair(norm_z, NR::Point(grid->origin[NR::X], y_proj_along_z_min)));
736 s.push_back(std::make_pair(norm_x, NR::Point(grid->origin[NR::X], y_proj_along_x_max)));
737 s.push_back(std::make_pair(component_vectors[NR::X], NR::Point(x_min, 0)));
738 }
740 return s;
741 }
743 void CanvasAxonomGridSnapper::_addSnappedLine(SnappedConstraints &sc, NR::Point const snapped_point, NR::Coord const snapped_distance, NR::Point const normal_to_line, NR::Point const point_on_line) const
744 {
745 SnappedLine dummy = SnappedLine(snapped_point, snapped_distance, getSnapperTolerance(), getSnapperAlwaysSnap(), normal_to_line, point_on_line);
746 sc.grid_lines.push_back(dummy);
747 }
751 }; // namespace Inkscape
754 /*
755 Local Variables:
756 mode:c++
757 c-file-style:"stroustrup"
758 c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
759 indent-tabs-mode:nil
760 fill-column:99
761 End:
762 */
763 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :