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