// This routine starts with some solution (current best or a random generated
// solution) and iteratively perturb changing some nodes and applying 2OPT.
bool TSP_Perturb2OPT(TSP_Data &tsp)
{
ListGraph *g;
int nchanges,i,j;
g = &tsp.g;
vector<Node> Circuit(tsp.NNodes), BestCircuit(tsp.NNodes);
double BestCircuitValue;
//nchanges = 2 (tests with some instances indicate that nchanges=1 is better
nchanges = 1;
// Start with a initial solution (if there is no solution, generate any sequence)
if (tsp.BestCircuitValue < DBL_MAX) {
BestCircuitValue = tsp.BestCircuitValue;
for (int i=0; i<tsp.NNodes; i++) BestCircuit[i] = tsp.BestCircuit[i];
} else {
int i=0;
BestCircuitValue = 0.0;
for (ListGraph::NodeIt v(*g); v!=INVALID; ++v) BestCircuit[i++]=v;
for (i=0;i<tsp.NNodes;i++)
BestCircuitValue +=
tsp.AdjMat.Cost(BestCircuit[i] , BestCircuit[(i+1)%tsp.NNodes]);
}
for (int it=0;it<tsp.max_perturb2opt_it;it++) {
if (!(it%100)) printf("[Heuristic: Perturbation+2OPT] it = %d (of %d)\n",it+1,tsp.max_perturb2opt_it);
for (int k=0;k<tsp.NNodes;k++) Circuit[k] = BestCircuit[k];
for (int nc=0;nc<nchanges;nc++) {
i = (int) (drand48()*tsp.NNodes); // get two random nodes and exchange
j = (int) (drand48()*tsp.NNodes); // their positions
if (i!=j) ChangeNode(Circuit[i],Circuit[j]);
}
Heuristic_2_OPT(tsp.AdjMat,Circuit,BestCircuitValue,tsp.NNodes);
if (BestCircuitValue < tsp.BestCircuitValue) { //update the best circuit used
tsp.BestCircuitValue = BestCircuitValue; // by the heuristic
for (int i=0;i<tsp.NNodes;i++) {
BestCircuit[i] = Circuit[i];
tsp.BestCircuit[i] = Circuit[i];
}
}
}
return(true);
}
void CharKeys (unsigned int key, bool special, bool release, int x, int y) {
int keyfact;
must_render = true;
if (ToolsFinalStage ()) {
if (key == SDLK_y || key == SDLK_j) {
SaveToolCharacter ();
SaveToolFrame ();
Winsys.Quit();
} else if (key == SDLK_n) Winsys.Quit ();
return;
}
if (key == 304) shift = !release;
if (key == 306) control = !release;
if (key == 308) alt = !release;
if (shift) keyfact = -1; else keyfact = 1;
if (release) return;
int type = action->type[curr_act];
switch (key) {
case SDLK_TAB: SetToolMode (1); break;
case SDLK_ESCAPE: case SDLK_q: QuitTool (); break;
case SDLK_F10: ScreenshotN (); break;
case SDLK_s: SaveToolCharacter (); break;
case SDLK_c: ScreenshotN (); break;
case SDLK_m: TestChar.useMaterials = !TestChar.useMaterials; break;
case SDLK_h: TestChar.useHighlighting = !TestChar.useHighlighting; break;
case SDLK_r:
TestChar.Reset ();
ReloadToolCharacter ();
ToolsInit ();
break;
case SDLK_u: if (action != NULL) {
RecallAction (action);
TestChar.RefreshNode (curr_node);
} break;
case SDLK_PLUS: case SDLK_EQUALS: // zoom in
zposition += 0.1;
xposition -= 0.03;
break;
case SDLK_MINUS: // zoom out
zposition -= 0.1;
xposition += 0.03;
break;
// set rotations for view
case SDLK_1: SetRotation (0, 0, 0); break;
case SDLK_2: SetRotation (-50, 180, 15); break;
case SDLK_3: SetRotation (0, 180, 0); break;
case SDLK_4: SetRotation (0, -80, 0); break;
// select node
case SDLK_PAGEUP: ChangeNode (-1); break;
case SDLK_PAGEDOWN: ChangeNode (1); break;
case SDLK_END: ChangeNode (charbase); break;
case SDLK_HOME: ChangeNode (-charbase); break;
// select action
case SDLK_DOWN:
if (curr_act < lastact) curr_act++;
if (action->type[curr_act] == 4) comp = 0; else comp = 1;
break;
case SDLK_UP:
if (curr_act > 0) curr_act--;
if (action->type[curr_act] == 4) comp = 0; else comp = 1;
break;
case SDLK_LEFT: ChangeValue (type, -1); break;
case SDLK_RIGHT: ChangeValue (type, 1); break;
// select value
case SDLK_SPACE:
if (type == 0 || type == 4) {
comp++;
if (comp > 3) comp = 0;
if (type == 0 && comp == 0) comp = 1;
} break;
default: break;
}
}