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