void MoleculeLayoutGraph::_assignFirstCycle (const Cycle &cycle)
{
// TODO: Start drawing from vertex with maximum code and continue to the right with one of two which has maximum code
int i, n;
float phi;
n = cycle.vertexCount();
for (i = 0; i < n; i++)
{
_layout_vertices[cycle.getVertex(i)].type = ELEMENT_BOUNDARY;
_layout_edges[cycle.getEdge(i)].type = ELEMENT_BOUNDARY;
}
_first_vertex_idx = cycle.getVertex(0);
_layout_vertices[cycle.getVertex(0)].pos.set(0.f, 0.f);
_layout_vertices[cycle.getVertex(1)].pos.set(1.f, 0.f);
phi = (float)M_PI * (n - 2) / n;
for (i = 1; i < n - 1; i++)
{
const Vec2f &v1 = _layout_vertices[cycle.getVertex(i - 1)].pos;
const Vec2f &v2 = _layout_vertices[cycle.getVertex(i)].pos;
_layout_vertices[cycle.getVertex(i + 1)].pos.rotateAroundSegmentEnd(v1, v2, phi);
}
}
// Split border in two parts by two vertices
void MoleculeLayoutGraph::_splitBorder (int v1, int v2, Array<int> &part1v, Array<int> &part1e, Array<int> &part2v, Array<int> &part2e) const
{
Cycle border;
_getBorder(border);
int idx1 = border.findVertex(v1);
int idx2 = border.findVertex(v2);
int i;
if (idx1 == -1 || idx2 == -1)
throw Error("border division by non-boundary vertex");
if (idx1 > idx2)
__swap(idx1, idx2, i);
part1v.clear();
part1e.clear();
part2v.clear();
part2e.clear();
for (i = idx1; i < idx2 + 1; i++)
{
part1v.push(border.getVertex(i));
part1e.push(border.getEdge(i));
}
part1e.pop(); // edge count is less
for (i = idx2; i < border.vertexCount(); i++)
{
part2v.push(border.getVertex(i));
part2e.push(border.getEdge(i));
}
for (i = 0; i < idx1 + 1; i++)
{
part2v.push(border.getVertex(i));
part2e.push(border.getEdge(i));
}
part2e.pop(); // edge count is less
}