int _IsolateMinorE1(graphP theGraph)
{
isolatorContextP IC = &theGraph->IC;
if (gp_GetVertexObstructionType(theGraph, IC->z) == VERTEX_OBSTRUCTIONTYPE_LOW_RXW)
{
gp_ResetVertexObstructionType(theGraph, IC->px, VERTEX_OBSTRUCTIONTYPE_HIGH_RXW);
IC->x=IC->z;
IC->ux=IC->uz;
IC->dx=IC->dz;
}
else if (gp_GetVertexObstructionType(theGraph, IC->z) == VERTEX_OBSTRUCTIONTYPE_LOW_RYW)
{
gp_ResetVertexObstructionType(theGraph, IC->py, VERTEX_OBSTRUCTIONTYPE_HIGH_RYW);
IC->y=IC->z;
IC->uy=IC->uz;
IC->dy=IC->dz;
}
else return NOTOK;
// Note: The x-y path is already marked, due to identifying E as the type of non-planarity minor,
// but the x-y path is also included in minor C, so we let it stay marked since the minor C
// isolator also assumes the x-y path has been marked by non-planarity minor type identification
IC->z = IC->uz = IC->dz = NIL;
theGraph->IC.minorType ^= MINORTYPE_E;
theGraph->IC.minorType |= (MINORTYPE_C|MINORTYPE_E1);
return _IsolateMinorC(theGraph);
}
int _IsolateKuratowskiSubgraph(graphP theGraph, int I, int R)
{
int RetVal;
/* A subgraph homeomorphic to K_{3,3} or K_5 will be isolated by using the visited
flags, 1=keep edge/vertex and 0=omit. Here we initialize to omit all, then we
subsequently set visited to 1 on all edges and vertices in the homeomorph. */
_FillVisitedFlags(theGraph, 0);
/* Next, we determine which of the non-planarity Minors was encountered
and the principal bicomp on which the isolator will focus attention. */
if (_ChooseTypeOfNonplanarityMinor(theGraph, I, R) != OK)
return NOTOK;
if (_InitializeIsolatorContext(theGraph) != OK)
return NOTOK;
/* Call the appropriate isolator */
if (theGraph->IC.minorType & MINORTYPE_A)
RetVal = _IsolateMinorA(theGraph);
else if (theGraph->IC.minorType & MINORTYPE_B)
RetVal = _IsolateMinorB(theGraph);
else if (theGraph->IC.minorType & MINORTYPE_C)
RetVal = _IsolateMinorC(theGraph);
else if (theGraph->IC.minorType & MINORTYPE_D)
RetVal = _IsolateMinorD(theGraph);
else if (theGraph->IC.minorType & MINORTYPE_E)
RetVal = _IsolateMinorE(theGraph);
else
RetVal = NOTOK;
/* Delete the unmarked edges and vertices, and return */
if (RetVal == OK)
RetVal = _DeleteUnmarkedVerticesAndEdges(theGraph);
return RetVal;
}
int _IsolateMinorE1(graphP theGraph)
{
isolatorContextP IC = &theGraph->IC;
if (theGraph->G[IC->z].type == VERTEX_LOW_RXW)
{
theGraph->G[IC->px].type = VERTEX_HIGH_RXW;
IC->x=IC->z; IC->ux=IC->uz; IC->dx=IC->dz;
}
else if (theGraph->G[IC->z].type == VERTEX_LOW_RYW)
{
theGraph->G[IC->py].type = VERTEX_HIGH_RYW;
IC->y=IC->z; IC->uy=IC->uz; IC->dy=IC->dz;
}
else return NOTOK;
IC->z = IC->uz = IC->dz = NIL;
theGraph->IC.minorType ^= MINORTYPE_E;
theGraph->IC.minorType |= (MINORTYPE_C|MINORTYPE_E1);
return _IsolateMinorC(theGraph);
}
int _IsolateMinorE1(graphP theGraph)
{
isolatorContextP IC = &theGraph->IC;
if (gp_GetVertexObstructionType(theGraph, IC->z) == VERTEX_OBSTRUCTIONTYPE_LOW_RXW)
{
gp_ResetVertexObstructionType(theGraph, IC->px, VERTEX_OBSTRUCTIONTYPE_HIGH_RXW);
IC->x=IC->z; IC->ux=IC->uz; IC->dx=IC->dz;
}
else if (gp_GetVertexObstructionType(theGraph, IC->z) == VERTEX_OBSTRUCTIONTYPE_LOW_RYW)
{
gp_ResetVertexObstructionType(theGraph, IC->py, VERTEX_OBSTRUCTIONTYPE_HIGH_RYW);
IC->y=IC->z; IC->uy=IC->uz; IC->dy=IC->dz;
}
else return NOTOK;
IC->z = IC->uz = IC->dz = NIL;
theGraph->IC.minorType ^= MINORTYPE_E;
theGraph->IC.minorType |= (MINORTYPE_C|MINORTYPE_E1);
return _IsolateMinorC(theGraph);
}
