#define INKSCAPE_CANVAS_GRID_C /* * * Copyright (C) Johan Engelen 2006-2007 * Copyright (C) Lauris Kaplinski 2000 * */ #include "sp-canvas-util.h" #include "display-forward.h" #include #include "desktop-handles.h" #include "helper/units.h" #include "svg/svg-color.h" #include "xml/node-event-vector.h" #include "sp-object.h" #include "sp-namedview.h" #include "inkscape.h" #include "desktop.h" #include "../document.h" #include "canvas-grid.h" #include "canvas-axonomgrid.h" namespace Inkscape { #define DEFAULTGRIDCOLOR 0x0000FF20 #define DEFAULTGRIDEMPCOLOR 0x0000FF40 static gchar const *const grid_name[] = { N_("Rectangular grid"), N_("Axonometric grid") }; static gchar const *const grid_svgname[] = { "xygrid", "axonomgrid" }; // ########################################################## // Grid CanvasItem static void grid_canvasitem_class_init (GridCanvasItemClass *klass); static void grid_canvasitem_init (GridCanvasItem *grid); static void grid_canvasitem_destroy (GtkObject *object); static void grid_canvasitem_update (SPCanvasItem *item, NR::Matrix const &affine, unsigned int flags); static void grid_canvasitem_render (SPCanvasItem *item, SPCanvasBuf *buf); static SPCanvasItemClass * parent_class; GtkType grid_canvasitem_get_type (void) { static GtkType grid_canvasitem_type = 0; if (!grid_canvasitem_type) { GtkTypeInfo grid_canvasitem_info = { "GridCanvasItem", sizeof (GridCanvasItem), sizeof (GridCanvasItemClass), (GtkClassInitFunc) grid_canvasitem_class_init, (GtkObjectInitFunc) grid_canvasitem_init, NULL, NULL, (GtkClassInitFunc) NULL }; grid_canvasitem_type = gtk_type_unique (sp_canvas_item_get_type (), &grid_canvasitem_info); } return grid_canvasitem_type; } static void grid_canvasitem_class_init (GridCanvasItemClass *klass) { GtkObjectClass *object_class; SPCanvasItemClass *item_class; object_class = (GtkObjectClass *) klass; item_class = (SPCanvasItemClass *) klass; parent_class = (SPCanvasItemClass*)gtk_type_class (sp_canvas_item_get_type ()); object_class->destroy = grid_canvasitem_destroy; item_class->update = grid_canvasitem_update; item_class->render = grid_canvasitem_render; } static void grid_canvasitem_init (GridCanvasItem *griditem) { griditem->grid = NULL; } static void grid_canvasitem_destroy (GtkObject *object) { g_return_if_fail (object != NULL); g_return_if_fail (INKSCAPE_IS_GRID_CANVASITEM (object)); if (GTK_OBJECT_CLASS (parent_class)->destroy) (* GTK_OBJECT_CLASS (parent_class)->destroy) (object); } /** */ static void grid_canvasitem_render (SPCanvasItem * item, SPCanvasBuf * buf) { GridCanvasItem *gridcanvasitem = INKSCAPE_GRID_CANVASITEM (item); sp_canvas_prepare_buffer (buf); if (gridcanvasitem->grid) gridcanvasitem->grid->Render(buf); } static void grid_canvasitem_update (SPCanvasItem *item, NR::Matrix const &affine, unsigned int flags) { GridCanvasItem *gridcanvasitem = INKSCAPE_GRID_CANVASITEM (item); if (parent_class->update) (* parent_class->update) (item, affine, flags); if (gridcanvasitem->grid) { gridcanvasitem->grid->Update(affine, flags); sp_canvas_request_redraw (item->canvas, -1000000, -1000000, 1000000, 1000000); item->x1 = item->y1 = -1000000; item->x2 = item->y2 = 1000000; } } // ########################################################## // CanvasGrid static Inkscape::XML::NodeEventVector const _repr_events = { NULL, /* child_added */ NULL, /* child_removed */ CanvasGrid::on_repr_attr_changed, NULL, /* content_changed */ NULL /* order_changed */ }; CanvasGrid::CanvasGrid(SPNamedView * nv, Inkscape::XML::Node * in_repr, SPDocument *in_doc) { repr = in_repr; doc = in_doc; if (repr) { repr->addListener (&_repr_events, this); } namedview = nv; canvasitems = NULL; } CanvasGrid::~CanvasGrid() { if (repr) { repr->removeListenerByData (this); } while (canvasitems) { gtk_object_destroy(GTK_OBJECT(canvasitems->data)); canvasitems = g_slist_remove(canvasitems, canvasitems->data); } } char const * CanvasGrid::getName(GridType type) { return _(grid_name[type]); } char const * CanvasGrid::getSVGName(GridType type) { return grid_svgname[type]; } GridType CanvasGrid::getGridTypeFromSVGName(char const *typestr) { if (!typestr) return GRID_RECTANGULAR; gint t = 0; for (t = GRID_MAXTYPENR; t >= 0; t--) { //this automatically defaults to grid0 which is rectangular grid if (!strcmp(typestr, grid_svgname[t])) break; } return (GridType) t; } GridType CanvasGrid::getGridTypeFromName(char const *typestr) { if (!typestr) return GRID_RECTANGULAR; gint t = 0; for (t = GRID_MAXTYPENR; t >= 0; t--) { //this automatically defaults to grid0 which is rectangular grid if (!strcmp(typestr, _(grid_name[t]))) break; } return (GridType) t; } /* * writes an child to repr. */ void CanvasGrid::writeNewGridToRepr(Inkscape::XML::Node * repr, SPDocument * doc, GridType gridtype) { if (!repr) return; if (gridtype > GRID_MAXTYPENR) return; // 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. Inkscape::XML::Document *xml_doc = sp_document_repr_doc(doc); Inkscape::XML::Node *newnode; newnode = xml_doc->createElement("inkscape:grid"); newnode->setAttribute("type", getSVGName(gridtype)); repr->appendChild(newnode); // Inkscape::GC::release(repr); FIX THIS. THIS SHOULD BE HERE!!! sp_document_done(doc, SP_VERB_DIALOG_NAMEDVIEW, _("Create new grid")); } /* * Creates a new CanvasGrid object of type gridtype */ CanvasGrid* CanvasGrid::NewGrid(SPNamedView * nv, Inkscape::XML::Node * repr, SPDocument * doc, GridType gridtype) { if (!repr) return NULL; if (!doc) { g_error("CanvasGrid::NewGrid - doc==NULL"); return NULL; } switch (gridtype) { case GRID_RECTANGULAR: return (CanvasGrid*) new CanvasXYGrid(nv, repr, doc); case GRID_AXONOMETRIC: return (CanvasGrid*) new CanvasAxonomGrid(nv, repr, doc); } return NULL; } /** * creates a new grid canvasitem for the SPDesktop given as parameter. Keeps a link to this canvasitem in the canvasitems list. */ GridCanvasItem * CanvasGrid::createCanvasItem(SPDesktop * desktop) { if (!desktop) return NULL; //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. // check if there is already a canvasitem on this desktop linking to this grid for (GSList *l = canvasitems; l != NULL; l = l->next) { if ( sp_desktop_gridgroup(desktop) == SP_CANVAS_GROUP(SP_CANVAS_ITEM(l->data)->parent) ) { return NULL; } } GridCanvasItem * item = INKSCAPE_GRID_CANVASITEM( sp_canvas_item_new(sp_desktop_gridgroup(desktop), INKSCAPE_TYPE_GRID_CANVASITEM, NULL) ); item->grid = this; sp_canvas_item_show(SP_CANVAS_ITEM(item)); gtk_object_ref(GTK_OBJECT(item)); // since we're keeping a link to this item, we need to bump up the ref count canvasitems = g_slist_prepend(canvasitems, item); return item; } void CanvasGrid::on_repr_attr_changed(Inkscape::XML::Node *repr, gchar const *key, gchar const *oldval, gchar const *newval, bool is_interactive, void *data) { if (!data) return; ((CanvasGrid*) data)->onReprAttrChanged(repr, key, oldval, newval, is_interactive); } // ########################################################## // CanvasXYGrid /** * "attach_all" function * A DIRECT COPY-PASTE FROM DOCUMENT-PROPERTIES.CPP TO QUICKLY GET RESULTS * * Helper function that attachs widgets in a 3xn table. The widgets come in an * array that has two entries per table row. The two entries code for four * possible cases: (0,0) means insert space in first column; (0, non-0) means * widget in columns 2-3; (non-0, 0) means label in columns 1-3; and * (non-0, non-0) means two widgets in columns 2 and 3. **/ #define SPACE_SIZE_X 15 #define SPACE_SIZE_Y 10 static inline void attach_all(Gtk::Table &table, Gtk::Widget const *const arr[], unsigned size, int start = 0) { for (unsigned i=0, r=start; i(*arr[i]), 1, 2, r, r+1, Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0); table.attach (const_cast(*arr[i+1]), 2, 3, r, r+1, Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0); } else { if (arr[i+1]) { table.attach (const_cast(*arr[i+1]), 1, 3, r, r+1, Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0); } else if (arr[i]) { Gtk::Label& label = reinterpret_cast (const_cast(*arr[i])); label.set_alignment (0.0); table.attach (label, 0, 3, r, r+1, Gtk::FILL|Gtk::EXPAND, (Gtk::AttachOptions)0,0,0); } else { Gtk::HBox *space = manage (new Gtk::HBox); space->set_size_request (SPACE_SIZE_X, SPACE_SIZE_Y); table.attach (*space, 0, 1, r, r+1, (Gtk::AttachOptions)0, (Gtk::AttachOptions)0,0,0); } } ++r; } } CanvasXYGrid::CanvasXYGrid (SPNamedView * nv, Inkscape::XML::Node * in_repr, SPDocument * in_doc) : CanvasGrid(nv, in_repr, in_doc), table(1, 1) { origin[NR::X] = origin[NR::Y] = 0.0; color = DEFAULTGRIDCOLOR; empcolor = DEFAULTGRIDEMPCOLOR; empspacing = 5; spacing[NR::X] = spacing[NR::Y] = 1.0; gridunit = &sp_unit_get_by_id(SP_UNIT_PX); render_dotted = false; snapper = new CanvasXYGridSnapper(this, namedview, 0); // initialize widgets: vbox.set_border_width(2); table.set_spacings(2); vbox.pack_start(table, false, false, 0); _rumg.init (_("Grid _units:"), "units", _wr, repr, doc); _rsu_ox.init (_("_Origin X:"), _("X coordinate of grid origin"), "originx", _rumg, _wr, repr, doc); _rsu_oy.init (_("O_rigin Y:"), _("Y coordinate of grid origin"), "originy", _rumg, _wr, repr, doc); _rsu_sx.init (_("Spacing _X:"), _("Distance between vertical grid lines"), "spacingx", _rumg, _wr, repr, doc); _rsu_sy.init (_("Spacing _Y:"), _("Distance between horizontal grid lines"), "spacingy", _rumg, _wr, repr, doc); _rcp_gcol.init (_("Grid line _color:"), _("Grid line color"), _("Color of grid lines"), "color", "opacity", _wr, repr, doc); _rcp_gmcol.init (_("Ma_jor grid line color:"), _("Major grid line color"), _("Color of the major (highlighted) grid lines"), "empcolor", "empopacity", _wr, repr, doc); _rsi.init (_("_Major grid line every:"), _("lines"), "empspacing", _wr, repr, doc); _rcb_dotted.init ( _("_Show dots instead of lines"), _("If set, displays dots at gridpoints instead of gridlines"), "dotted", _wr, false, repr, doc); Gtk::Widget const *const widget_array[] = { _rumg._label, _rumg._sel, 0, _rsu_ox.getSU(), 0, _rsu_oy.getSU(), 0, _rsu_sx.getSU(), 0, _rsu_sy.getSU(), _rcp_gcol._label, _rcp_gcol._cp, 0, 0, _rcp_gmcol._label, _rcp_gmcol._cp, _rsi._label, &_rsi._hbox, 0, _rcb_dotted._button, }; attach_all (table, widget_array, sizeof(widget_array)); vbox.show(); if (repr) readRepr(); updateWidgets(); } CanvasXYGrid::~CanvasXYGrid () { if (snapper) delete snapper; } /* fixme: Collect all these length parsing methods and think common sane API */ static gboolean sp_nv_read_length(gchar const *str, guint base, gdouble *val, SPUnit const **unit) { if (!str) { return FALSE; } gchar *u; gdouble v = g_ascii_strtod(str, &u); if (!u) { return FALSE; } while (isspace(*u)) { u += 1; } if (!*u) { /* No unit specified - keep default */ *val = v; return TRUE; } if (base & SP_UNIT_DEVICE) { if (u[0] && u[1] && !isalnum(u[2]) && !strncmp(u, "px", 2)) { *unit = &sp_unit_get_by_id(SP_UNIT_PX); *val = v; return TRUE; } } if (base & SP_UNIT_ABSOLUTE) { if (!strncmp(u, "pt", 2)) { *unit = &sp_unit_get_by_id(SP_UNIT_PT); } else if (!strncmp(u, "mm", 2)) { *unit = &sp_unit_get_by_id(SP_UNIT_MM); } else if (!strncmp(u, "cm", 2)) { *unit = &sp_unit_get_by_id(SP_UNIT_CM); } else if (!strncmp(u, "m", 1)) { *unit = &sp_unit_get_by_id(SP_UNIT_M); } else if (!strncmp(u, "in", 2)) { *unit = &sp_unit_get_by_id(SP_UNIT_IN); } else { return FALSE; } *val = v; return TRUE; } return FALSE; } static gboolean sp_nv_read_opacity(gchar const *str, guint32 *color) { if (!str) { return FALSE; } gchar *u; gdouble v = g_ascii_strtod(str, &u); if (!u) { return FALSE; } v = CLAMP(v, 0.0, 1.0); *color = (*color & 0xffffff00) | (guint32) floor(v * 255.9999); return TRUE; } /** If the passed scalar is invalid (<=0), then set the widget and the scalar to use the given old value. @param oldVal Old value to use if the new one is invalid. @param pTarget The scalar to validate. @param widget Widget associated with the scalar. */ static void validateScalar(double oldVal, double* pTarget, Inkscape::UI::Widget::RegisteredScalarUnit& widget) { // Avoid nullness. if ( pTarget == NULL ) return; // Invalid new value? if ( *pTarget <= 0 ) { // If the old value is somehow invalid as well, then default to 1. if ( oldVal <= 0 ) oldVal = 1; // Reset the scalar and associated widget to the old value. *pTarget = oldVal; widget.setValue( *pTarget); } //if } //validateScalar /** If the passed int is invalid (<=0), then set the widget and the int to use the given old value. @param oldVal Old value to use if the new one is invalid. @param pTarget The int to validate. @param widget Widget associated with the int. */ static void validateInt(gint oldVal, gint* pTarget, Inkscape::UI::Widget::RegisteredSuffixedInteger& widget) { // Avoid nullness. if ( pTarget == NULL ) return; // Invalid new value? if ( *pTarget <= 0 ) { // If the old value is somehow invalid as well, then default to 1. if ( oldVal <= 0 ) oldVal = 1; // Reset the int and associated widget to the old value. *pTarget = oldVal; widget.setValue( *pTarget); } //if } //validateInt void CanvasXYGrid::readRepr() { char buff[100]; gchar const *value; if ( (value = repr->attribute("originx")) ) { sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::X], &gridunit); origin[NR::X] = sp_units_get_pixels(origin[NR::X], *(gridunit)); } if ( (value = repr->attribute("originy")) ) { sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &origin[NR::Y], &gridunit); origin[NR::Y] = sp_units_get_pixels(origin[NR::Y], *(gridunit)); } if ( (value = repr->attribute("spacingx")) ) { double oldVal = spacing[NR::X]; sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &spacing[NR::X], &gridunit); validateScalar( oldVal, &spacing[NR::X], _rsu_sx ); spacing[NR::X] = sp_units_get_pixels(spacing[NR::X], *(gridunit)); } if ( (value = repr->attribute("spacingy")) ) { double oldVal = spacing[NR::Y]; sp_nv_read_length(value, SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE, &spacing[NR::Y], &gridunit); validateScalar( oldVal, &spacing[NR::Y], _rsu_sy ); spacing[NR::Y] = sp_units_get_pixels(spacing[NR::Y], *(gridunit)); } if ( (value = repr->attribute("color")) ) { color = (color & 0xff) | sp_svg_read_color(value, color); } if ( (value = repr->attribute("empcolor")) ) { empcolor = (empcolor & 0xff) | sp_svg_read_color(value, empcolor); } if ( (value = repr->attribute("opacity")) ) { sp_nv_read_opacity(value, &color); } if ( (value = repr->attribute("empopacity")) ) { sp_nv_read_opacity(value, &empcolor); } if ( (value = repr->attribute("empspacing")) ) { gint oldVal = empspacing; empspacing = atoi(value); validateInt( oldVal, &empspacing, _rsi ); } if ( (value = repr->attribute("dotted")) ) { render_dotted = (strcmp(value,"true") == 0); } for (GSList *l = canvasitems; l != NULL; l = l->next) { sp_canvas_item_request_update ( SP_CANVAS_ITEM(l->data) ); } return; } /** * Called when XML node attribute changed; updates dialog widgets if change was not done by widgets themselves. */ void CanvasXYGrid::onReprAttrChanged(Inkscape::XML::Node *repr, gchar const *key, gchar const *oldval, gchar const *newval, bool is_interactive) { readRepr(); if ( ! (_wr.isUpdating()) ) updateWidgets(); } Gtk::Widget & CanvasXYGrid::getWidget() { return vbox; } /** * Update dialog widgets from object's values. */ void CanvasXYGrid::updateWidgets() { if (_wr.isUpdating()) return; _wr.setUpdating (true); _rumg.setUnit (gridunit); gdouble val; val = origin[NR::X]; val = sp_pixels_get_units (val, *(gridunit)); _rsu_ox.setValue (val); val = origin[NR::Y]; val = sp_pixels_get_units (val, *(gridunit)); _rsu_oy.setValue (val); val = spacing[NR::X]; double gridx = sp_pixels_get_units (val, *(gridunit)); _rsu_sx.setValue (gridx); val = spacing[NR::Y]; double gridy = sp_pixels_get_units (val, *(gridunit)); _rsu_sy.setValue (gridy); _rcp_gcol.setRgba32 (color); _rcp_gmcol.setRgba32 (empcolor); _rsi.setValue (empspacing); _wr.setUpdating (false); return; } void CanvasXYGrid::Update (NR::Matrix const &affine, unsigned int flags) { ow = origin * affine; sw = spacing * affine; sw -= NR::Point(affine[4], affine[5]); for(int dim = 0; dim < 2; dim++) { gint scaling_factor = empspacing; if (scaling_factor <= 1) scaling_factor = 5; scaled[dim] = FALSE; sw[dim] = fabs (sw[dim]); while (sw[dim] < 8.0) { scaled[dim] = TRUE; sw[dim] *= scaling_factor; /* First pass, go up to the major line spacing, then keep increasing by two. */ scaling_factor = 2; } } } static void grid_hline (SPCanvasBuf *buf, gint y, gint xs, gint xe, guint32 rgba) { if ((y >= buf->rect.y0) && (y < buf->rect.y1)) { guint r, g, b, a; gint x0, x1, x; guchar *p; r = NR_RGBA32_R (rgba); g = NR_RGBA32_G (rgba); b = NR_RGBA32_B (rgba); a = NR_RGBA32_A (rgba); x0 = MAX (buf->rect.x0, xs); x1 = MIN (buf->rect.x1, xe + 1); p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x0 - buf->rect.x0) * 3; for (x = x0; x < x1; x++) { p[0] = NR_COMPOSEN11_1111 (r, a, p[0]); p[1] = NR_COMPOSEN11_1111 (g, a, p[1]); p[2] = NR_COMPOSEN11_1111 (b, a, p[2]); p += 3; } } } static void grid_vline (SPCanvasBuf *buf, gint x, gint ys, gint ye, guint32 rgba) { if ((x >= buf->rect.x0) && (x < buf->rect.x1)) { guint r, g, b, a; gint y0, y1, y; guchar *p; r = NR_RGBA32_R(rgba); g = NR_RGBA32_G (rgba); b = NR_RGBA32_B (rgba); a = NR_RGBA32_A (rgba); y0 = MAX (buf->rect.y0, ys); y1 = MIN (buf->rect.y1, ye + 1); p = buf->buf + (y0 - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3; for (y = y0; y < y1; y++) { p[0] = NR_COMPOSEN11_1111 (r, a, p[0]); p[1] = NR_COMPOSEN11_1111 (g, a, p[1]); p[2] = NR_COMPOSEN11_1111 (b, a, p[2]); p += buf->buf_rowstride; } } } static void grid_dot (SPCanvasBuf *buf, gint x, gint y, guint32 rgba) { if ( (y >= buf->rect.y0) && (y < buf->rect.y1) && (x >= buf->rect.x0) && (x < buf->rect.x1) ) { guint r, g, b, a; guchar *p; r = NR_RGBA32_R (rgba); g = NR_RGBA32_G (rgba); b = NR_RGBA32_B (rgba); a = NR_RGBA32_A (rgba); p = buf->buf + (y - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3; p[0] = NR_COMPOSEN11_1111 (r, a, p[0]); p[1] = NR_COMPOSEN11_1111 (g, a, p[1]); p[2] = NR_COMPOSEN11_1111 (b, a, p[2]); } } void CanvasXYGrid::Render (SPCanvasBuf *buf) { gdouble const sxg = floor ((buf->rect.x0 - ow[NR::X]) / sw[NR::X]) * sw[NR::X] + ow[NR::X]; gint const xlinestart = (gint) Inkscape::round((sxg - ow[NR::X]) / sw[NR::X]); gdouble const syg = floor ((buf->rect.y0 - ow[NR::Y]) / sw[NR::Y]) * sw[NR::Y] + ow[NR::Y]; gint const ylinestart = (gint) Inkscape::round((syg - ow[NR::Y]) / sw[NR::Y]); if (!render_dotted) { gint ylinenum; gdouble y; for (y = syg, ylinenum = ylinestart; y < buf->rect.y1; y += sw[NR::Y], ylinenum++) { gint const y0 = (gint) Inkscape::round(y); if (!scaled[NR::Y] && (ylinenum % empspacing) == 0) { grid_hline (buf, y0, buf->rect.x0, buf->rect.x1 - 1, empcolor); } else { grid_hline (buf, y0, buf->rect.x0, buf->rect.x1 - 1, color); } } gint xlinenum; gdouble x; for (x = sxg, xlinenum = xlinestart; x < buf->rect.x1; x += sw[NR::X], xlinenum++) { gint const ix = (gint) Inkscape::round(x); if (!scaled[NR::X] && (xlinenum % empspacing) == 0) { grid_vline (buf, ix, buf->rect.y0, buf->rect.y1, empcolor); } else { grid_vline (buf, ix, buf->rect.y0, buf->rect.y1, color); } } } else { gint ylinenum; gdouble y; for (y = syg, ylinenum = ylinestart; y < buf->rect.y1; y += sw[NR::Y], ylinenum++) { gint const iy = (gint) Inkscape::round(y); gint xlinenum; gdouble x; for (x = sxg, xlinenum = xlinestart; x < buf->rect.x1; x += sw[NR::X], xlinenum++) { gint const ix = (gint) Inkscape::round(x); if ( (!scaled[NR::X] && (xlinenum % empspacing) == 0) || (!scaled[NR::Y] && (ylinenum % empspacing) == 0) ) { grid_dot (buf, ix, iy, empcolor | (guint32)0x000000FF); // put alpha to max value } else { grid_dot (buf, ix, iy, color | (guint32)0x000000FF); // put alpha to max value } } } } } /** * \return x rounded to the nearest multiple of c1 plus c0. * * \note * If c1==0 (and c0 is finite), then returns +/-inf. This makes grid spacing of zero * mean "ignore the grid in this dimention". We're currently discussing "good" semantics * for guide/grid snapping. */ /* FIXME: move this somewhere else, perhaps */ static double round_to_nearest_multiple_plus(double x, double const c1, double const c0) { return floor((x - c0) / c1 + .5) * c1 + c0; } CanvasXYGridSnapper::CanvasXYGridSnapper(CanvasXYGrid *grid, SPNamedView const *nv, NR::Coord const d) : LineSnapper(nv, d) { this->grid = grid; } LineSnapper::LineList CanvasXYGridSnapper::_getSnapLines(NR::Point const &p) const { LineList s; if ( grid == NULL ) { return s; } for (unsigned int i = 0; i < 2; ++i) { /* This is to make sure we snap to only visible grid lines */ double scaled_spacing = grid->sw[i]; // this is spacing of visible lines if screen pixels // convert screen pixels to px // FIXME: after we switch to snapping dist in screen pixels, this will be unnecessary if (SP_ACTIVE_DESKTOP) { scaled_spacing /= SP_ACTIVE_DESKTOP->current_zoom(); } NR::Coord const rounded = round_to_nearest_multiple_plus(p[i], scaled_spacing, grid->origin[i]); s.push_back(std::make_pair(NR::Dim2(i), rounded)); } return s; } }; /* namespace Inkscape */ /* Local Variables: mode:c++ c-file-style:"stroustrup" c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) indent-tabs-mode:nil fill-column:99 End: */ // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :