src/graphlayout.cpp

   1 /** @file
   2  * @brief Interface between Inkscape code (SPItem) and graphlayout functions.
   3  */
   4 /*
   5  * Authors:
   6  *   Tim Dwyer <Tim.Dwyer@infotech.monash.edu.au>
   7  *   Abhishek Sharma
   8  *
   9  * Copyright (C) 2005 Authors
  10  *
  11  * Released under GNU GPL.  Read the file 'COPYING' for more information.
  12  */
  13
  14 #include <iostream>
  15 #include <config.h>
  16 #include <map>
  17 #include <vector>
  18 #include <algorithm>
  19 #include <cstring>
  20 #include <cstdlib>
  21 #include <float.h>
  22
  23 #include "desktop.h"
  24 #include "inkscape.h"
  25 #include "sp-namedview.h"
  26 #include "util/glib-list-iterators.h"
  27 #include "graphlayout.h"
  28 #include "sp-path.h"
  29 #include "sp-item.h"
  30 #include "sp-item-transform.h"
  31 #include "sp-conn-end-pair.h"
  32 #include "style.h"
  33 #include "conn-avoid-ref.h"
  34 #include "libavoid/connector.h"
  35 #include "libavoid/router.h"
  36 #include "libavoid/geomtypes.h"
  37 #include "libcola/cola.h"
  38 #include "libvpsc/generate-constraints.h"
  39 #include "preferences.h"
  40
  41 using namespace std;
  42 using namespace cola;
  43 using namespace vpsc;
  44 /**
  45  * Returns true if item is a connector
  46  */
  47 bool isConnector(SPItem const *const i) {
  48     SPPath *path = NULL;
  49     if(SP_IS_PATH(i)) {
  50         path = SP_PATH(i);
  51     }
  52     return path && path->connEndPair.isAutoRoutingConn();
  53 }
  54
  55 struct CheckProgress : TestConvergence {
  56     CheckProgress(double d,unsigned i,list<SPItem *>&
  57                   selected,vector<Rectangle*>& rs,map<string,unsigned>& nodelookup) :
  58         TestConvergence(d,i), selected(selected), rs(rs), nodelookup(nodelookup) {}
  59     bool operator()(double new_stress, double* X, double* Y) {
  60         /* This is where, if we wanted to animate the layout, we would need to update
  61          * the positions of all objects and redraw the canvas and maybe sleep a bit
  62          cout << "stress="<<new_stress<<endl;
  63         cout << "x[0]="<<rs[0]->getMinX()<<endl;
  64         for (list<SPItem *>::iterator it(selected.begin());
  65             it != selected.end();
  66             ++it)
  67         {
  68             SPItem *u=*it;
  69             if(!isConnector(u)) {
  70                 Rectangle* r=rs[nodelookup[u->id]];
  71                 Geom::Rect const item_box(sp_item_bbox_desktop(u));
  72                 Geom::Point const curr(item_box.midpoint());
  73                 Geom::Point const dest(r->getCentreX(),r->getCentreY());
  74                 sp_item_move_rel(u, Geom::Translate(dest - curr));
  75             }
  76         }
  77         */
  78         return TestConvergence::operator()(new_stress,X,Y);
  79     }
  80     list<SPItem *>& selected;
  81     vector<Rectangle*>& rs;
  82     map<string,unsigned>& nodelookup;
  83 };
  84
  85 /**
  86  * Scans the items list and places those items that are
  87  * not connectors in filtered
  88  */
  89 void filterConnectors(GSList const *const items, list<SPItem *> &filtered) {
  90     for(GSList *i=(GSList *)items; i!=NULL; i=i->next) {
  91         SPItem *item=SP_ITEM(i->data);
  92         if(!isConnector(item)) {
  93             filtered.push_back(item);
  94         }
  95     }
  96 }
  97 /**
  98 * Takes a list of inkscape items, extracts the graph defined by
  99 * connectors between them, and uses graph layout techniques to find
 100 * a nice layout
 101 */
 102 void graphlayout(GSList const *const items) {
 103     if(!items) {
 104         return;
 105     }
 106
 107     using Inkscape::Util::GSListConstIterator;
 108     list<SPItem *> selected;
 109     filterConnectors(items,selected);
 110     if (selected.empty()) return;
 111
 112     const unsigned n=selected.size();
 113     //Check 2 or more selected objects
 114     if (n < 2) return;
 115
 116     // add the connector spacing to the size of node bounding boxes
 117     // so that connectors can always be routed between shapes
 118     SPDesktop* desktop = inkscape_active_desktop();
 119     double spacing = 0;
 120     if(desktop) spacing = desktop->namedview->connector_spacing+0.1;
 121
 122     map<string,unsigned> nodelookup;
 123     vector<Rectangle*> rs;
 124     vector<Edge> es;
 125     for (list<SPItem *>::iterator i(selected.begin());
 126          i != selected.end();
 127          ++i)
 128     {
 129         SPItem *u=*i;
 130         Geom::OptRect const item_box(u->getBboxDesktop());
 131         if(item_box) {
 132             Geom::Point ll(item_box->min());
 133             Geom::Point ur(item_box->max());
 134             nodelookup[u->getId()]=rs.size();
 135             rs.push_back(new Rectangle(ll[0]-spacing,ur[0]+spacing,
 136                         ll[1]-spacing,ur[1]+spacing));
 137         } else {
 138             // I'm not actually sure if it's possible for something with a
 139             // NULL item-box to be attached to a connector in which case we
 140             // should never get to here... but if such a null box can occur it's
 141             // probably pretty safe to simply ignore
 142             //fprintf(stderr,"NULL item_box found in graphlayout, ignoring!\n");
 143         }
 144     }
 145
 146     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
 147     SimpleConstraints scx,scy;
 148     double ideal_connector_length = prefs->getDouble("/tools/connector/length", 100.0);
 149     double directed_edge_height_modifier = 1.0;
 150
 151     bool directed =       prefs->getBool("/tools/connector/directedlayout");
 152     bool avoid_overlaps = prefs->getBool("/tools/connector/avoidoverlaplayout");
 153
 154     for (list<SPItem *>::iterator i(selected.begin());
 155          i != selected.end();
 156          ++i)
 157     {
 158         SPItem *iu=*i;
 159         map<string,unsigned>::iterator i=nodelookup.find(iu->getId());
 160         if(i==nodelookup.end()) {
 161             continue;
 162         }
 163         unsigned u=i->second;
 164         GSList *nlist=iu->avoidRef->getAttachedConnectors(Avoid::runningFrom);
 165         list<SPItem *> connectors;
 166
 167         connectors.insert<GSListConstIterator<SPItem *> >(connectors.end(),nlist,NULL);
 168         for (list<SPItem *>::iterator j(connectors.begin());
 169                 j != connectors.end();
 170                 ++j) {
 171             SPItem *conn=*j;
 172             SPItem *iv;
 173             SPItem *items[2];
 174             assert(isConnector(conn));
 175             SP_PATH(conn)->connEndPair.getAttachedItems(items);
 176             if(items[0]==iu) {
 177                 iv=items[1];
 178             } else {
 179                 iv=items[0];
 180             }
 181
 182             if (iv == NULL) {
 183                 // The connector is not attached to anything at the
 184                 // other end so we should just ignore it.
 185                 continue;
 186             }
 187
 188             // If iv not in nodelookup we again treat the connector
 189             // as disconnected and continue
 190             map<string,unsigned>::iterator v_pair=nodelookup.find(iv->getId());
 191             if(v_pair!=nodelookup.end()) {
 192                 unsigned v=v_pair->second;
 193                 //cout << "Edge: (" << u <<","<<v<<")"<<endl;
 194                 es.push_back(make_pair(u,v));
 195                 if(conn->style->marker[SP_MARKER_LOC_END].set) {
 196                     if(directed && strcmp(conn->style->marker[SP_MARKER_LOC_END].value,"none")) {
 197                         scy.push_back(new SimpleConstraint(v, u,
 198                                     (ideal_connector_length * directed_edge_height_modifier)));
 199                     }
 200                 }
 201             }
 202         }
 203         if(nlist) {
 204             g_slist_free(nlist);
 205         }
 206     }
 207     const unsigned E = es.size();
 208     double eweights[E];
 209     fill(eweights,eweights+E,1);
 210     vector<Component*> cs;
 211     connectedComponents(rs,es,scx,scy,cs);
 212     for(unsigned i=0;i<cs.size();i++) {
 213         Component* c=cs[i];
 214         if(c->edges.size()<2) continue;
 215         CheckProgress test(0.0001,100,selected,rs,nodelookup);
 216         ConstrainedMajorizationLayout alg(c->rects,c->edges,eweights,ideal_connector_length,test);
 217         alg.setupConstraints(NULL,NULL,avoid_overlaps,
 218                 NULL,NULL,&c->scx,&c->scy,NULL,NULL);
 219         alg.run();
 220     }
 221     separateComponents(cs);
 222
 223     for (list<SPItem *>::iterator it(selected.begin());
 224          it != selected.end();
 225          ++it)
 226     {
 227         SPItem *u=*it;
 228         if(!isConnector(u)) {
 229             map<string,unsigned>::iterator i=nodelookup.find(u->getId());
 230             if(i!=nodelookup.end()) {
 231                 Rectangle* r=rs[i->second];
 232                 Geom::OptRect item_box(u->getBboxDesktop());
 233                 if(item_box) {
 234                     Geom::Point const curr(item_box->midpoint());
 235                     Geom::Point const dest(r->getCentreX(),r->getCentreY());
 236                     sp_item_move_rel(u, Geom::Translate(dest - curr));
 237                 }
 238             }
 239         }
 240     }
 241     for(unsigned i=0;i<scx.size();i++) {
 242         delete scx[i];
 243     }
 244     for(unsigned i=0;i<scy.size();i++) {
 245         delete scy[i];
 246     }
 247     for(unsigned i=0;i<rs.size();i++) {
 248         delete rs[i];
 249     }
 250 }
 251 // vim: set cindent
 252 // vim: ts=4 sw=4 et tw=0 wm=0
 253
 254 /*
 255   Local Variables:
 256   mode:c++
 257   c-file-style:"stroustrup"
 258   c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
 259   indent-tabs-mode:nil
 260   fill-column:99
 261   End:
 262 */
 263 // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :