src/graphlayout/graphlayout.cpp

   1 /** \file
   2  * Interface between Inkscape code (SPItem) and graphlayout functions.
   3  */
   4 /*
   5 * Authors:
   6 *   Tim Dwyer <Tim.Dwyer@infotech.monash.edu.au>
   7 *
   8 * Copyright (C) 2005 Authors
   9 *
  10 * Released under GNU GPL.  Read the file 'COPYING' for more information.
  11 */
  12 #include <iostream>
  13 #include <config.h>
  14 #include <map>
  15 #include <vector>
  16 #include <algorithm>
  17 #include <float.h>
  18
  19 #include "desktop.h"
  20 #include "inkscape.h"
  21 #include "sp-namedview.h"
  22 #include "util/glib-list-iterators.h"
  23 #include "graphlayout/graphlayout.h"
  24 #include "sp-path.h"
  25 #include "sp-item.h"
  26 #include "sp-item-transform.h"
  27 #include "sp-conn-end-pair.h"
  28 #include "style.h"
  29 #include "conn-avoid-ref.h"
  30 #include "libavoid/connector.h"
  31 #include "libavoid/geomtypes.h"
  32 #include "libcola/cola.h"
  33 #include "libvpsc/generate-constraints.h"
  34 #include "prefs-utils.h"
  35
  36 using namespace std;
  37 using namespace cola;
  38 using namespace vpsc;
  39
  40 /**
  41  * Returns true if item is a connector
  42  */
  43 bool isConnector(SPItem const *const i) {
  44         SPPath *path = NULL;
  45         if(SP_IS_PATH(i)) {
  46                 path = SP_PATH(i);
  47         }
  48         return path && path->connEndPair.isAutoRoutingConn();
  49 }
  50
  51 /**
  52  * Scans the items list and places those items that are
  53  * not connectors in filtered
  54  */
  55 void filterConnectors(GSList const *const items, list<SPItem *> &filtered) {
  56         for(GSList *i=(GSList *)items; i!=NULL; i=i->next) {
  57                 SPItem *item=SP_ITEM(i->data);
  58                 if(!isConnector(item)) {
  59                         filtered.push_back(item);
  60                 }
  61         }
  62 }
  63 /**
  64 * Takes a list of inkscape items, extracts the graph defined by
  65 * connectors between them, and uses graph layout techniques to find
  66 * a nice layout
  67 */
  68 void graphlayout(GSList const *const items) {
  69         if(!items) {
  70                 return;
  71         }
  72
  73         using Inkscape::Util::GSListConstIterator;
  74         list<SPItem *> selected;
  75         filterConnectors(items,selected);
  76         if (selected.empty()) return;
  77
  78         const unsigned n=selected.size();
  79         //Check 2 or more selected objects
  80         if (n < 2) return;
  81
  82     // add the connector spacing to the size of node bounding boxes
  83     // so that connectors can always be routed between shapes
  84     SPDesktop* desktop = inkscape_active_desktop();
  85     double spacing = 0;
  86     if(desktop) spacing = desktop->namedview->connector_spacing+0.1;
  87
  88         map<string,unsigned> nodelookup;
  89         vector<Rectangle*> rs;
  90         vector<Edge> es;
  91         for (list<SPItem *>::iterator i(selected.begin());
  92                 i != selected.end();
  93                 ++i)
  94         {
  95                 SPItem *u=*i;
  96                 NR::Maybe<NR::Rect> const item_box(sp_item_bbox_desktop(u));
  97         g_assert(item_box);
  98                 NR::Point ll(item_box->min());
  99                 NR::Point ur(item_box->max());
 100                 nodelookup[u->id]=rs.size();
 101                 rs.push_back(new Rectangle(ll[0]-spacing,ur[0]+spacing,
 102                     ll[1]-spacing,ur[1]+spacing));
 103         }
 104
 105         SimpleConstraints scx,scy;
 106         double ideal_connector_length = prefs_get_double_attribute("tools.connector","length",100);
 107         double directed_edge_height_modifier = 1.0;
 108         gchar const *directed_str = NULL, *overlaps_str = NULL;
 109         directed_str = prefs_get_string_attribute("tools.connector",
 110                         "directedlayout");
 111         overlaps_str = prefs_get_string_attribute("tools.connector",
 112                         "avoidoverlaplayout");
 113         bool avoid_overlaps = false;
 114         bool directed = false;
 115     if (directed_str && !strcmp(directed_str, "true")) {
 116             directed = true;
 117         }
 118     if (overlaps_str && !strcmp(overlaps_str, "true")) {
 119             avoid_overlaps = true;
 120         }
 121
 122         for (list<SPItem *>::iterator i(selected.begin());
 123                 i != selected.end();
 124                 ++i)
 125         {
 126                 SPItem *iu=*i;
 127                 unsigned u=nodelookup[iu->id];
 128                 GSList *nlist=iu->avoidRef->getAttachedConnectors(Avoid::runningFrom);
 129                 list<SPItem *> connectors;
 130
 131                 connectors.insert<GSListConstIterator<SPItem *> >(connectors.end(),nlist,NULL);
 132                 for (list<SPItem *>::iterator j(connectors.begin());
 133                                 j != connectors.end();
 134                                 ++j) {
 135                         SPItem *conn=*j;
 136                         SPItem *iv;
 137                         SPItem *items[2];
 138                         assert(isConnector(conn));
 139                         SP_PATH(conn)->connEndPair.getAttachedItems(items);
 140                         if(items[0]==iu) {
 141                                 iv=items[1];
 142                         } else {
 143                                 iv=items[0];
 144                         }
 145
 146             if (iv == NULL) {
 147                 // The connector is not attached to anything at the
 148                 // other end so we should just ignore it.
 149                 continue;
 150             }
 151
 152                         // What do we do if iv not in nodelookup?!?!
 153                         map<string,unsigned>::iterator v_pair=nodelookup.find(iv->id);
 154                         if(v_pair!=nodelookup.end()) {
 155                                 unsigned v=v_pair->second;
 156                                 //cout << "Edge: (" << u <<","<<v<<")"<<endl;
 157                                 es.push_back(make_pair(u,v));
 158                                 if(conn->style->marker[SP_MARKER_LOC_END].set) {
 159                                         if(directed && strcmp(conn->style->marker[SP_MARKER_LOC_END].value,"none")) {
 160                                                 scy.push_back(new SimpleConstraint(v, u,
 161                                     (ideal_connector_length * directed_edge_height_modifier)));
 162                                         }
 163                                 }
 164                         }
 165                 }
 166                 if(nlist) {
 167                         g_slist_free(nlist);
 168                 }
 169         }
 170         const unsigned E = es.size();
 171         double eweights[E];
 172         fill(eweights,eweights+E,1);
 173     vector<Component*> cs;
 174     connectedComponents(rs,es,scx,scy,cs);
 175     for(unsigned i=0;i<cs.size();i++) {
 176         Component* c=cs[i];
 177         if(c->edges.size()<2) continue;
 178         ConstrainedMajorizationLayout alg(c->rects,c->edges,eweights,ideal_connector_length);
 179         alg.setupConstraints(NULL,NULL,avoid_overlaps,
 180                 NULL,NULL,&c->scx,&c->scy,NULL,NULL);
 181         alg.run();
 182     }
 183     separateComponents(cs);
 184
 185         for (list<SPItem *>::iterator it(selected.begin());
 186                 it != selected.end();
 187                 ++it)
 188         {
 189                 SPItem *u=*it;
 190                 if(!isConnector(u)) {
 191                         Rectangle* r=rs[nodelookup[u->id]];
 192                         NR::Maybe<NR::Rect> item_box(sp_item_bbox_desktop(u));
 193             g_assert(item_box);
 194                         NR::Point const curr(item_box->midpoint());
 195                         NR::Point const dest(r->getCentreX(),r->getCentreY());
 196                         sp_item_move_rel(u, NR::translate(dest - curr));
 197                 }
 198         }
 199     for(unsigned i=0;i<scx.size();i++) {
 200         delete scx[i];
 201     }
 202     for(unsigned i=0;i<scy.size();i++) {
 203         delete scy[i];
 204     }
 205     for(unsigned i=0;i<rs.size();i++) {
 206         delete rs[i];
 207     }
 208 }
 209 // vim: set cindent
 210 // vim: ts=4 sw=4 et tw=0 wm=0