void Delaunay::addBounding( const VertexVector &verSet,
TriangleVector &triSet )
{
double max_x = -100000, max_y = -100000;
double min_x = 100000, min_y = 100000;
for (int i = 0; i < verSet.size(); i++)
{
Vec3d v = verSet[i].m_xyz;
max_x = max_x < v[0] ? v[0] : max_x;
min_x = min_x > v[0] ? v[0] : min_x;
max_y = max_y < v[1] ? v[1] : max_y;
min_y = min_y > v[1] ? v[1] : min_y;
}
// 将矩形区域的外接三角形作为边界
double dx = max_x - min_x;
double dy = max_y - min_y;
double mid_x = (min_x + max_x) / 2;
double mid_y = (min_y + max_y) / 2;
// 为了去除边界方便讲边界点的索引置为负数
Vertex v0(Vec3d(mid_x, max_y + dy, 0.0f), -1);
Vertex v1(Vec3d(mid_x - dx, min_y, 0.0f), -2);
Vertex v2(Vec3d(mid_x + dx, min_y, 0.0f), -3);
triSet.push_back(Triangle(v0, v1, v2));
}
void Delaunay::removeBounding( TriangleVector inSet,
TriangleVector &outSet, const int &index )
{
for (TriangleVector::iterator iter = inSet.begin();
iter != inSet.end(); iter++)
{
if (iter->m_vertices[0].m_index >= 0 &&
iter->m_vertices[1].m_index >= 0 &&
iter->m_vertices[2].m_index >= 0 &&
iter->isVertex(index) &&
iter->angleCriterion(m_minAngle, m_maxAngle))
{
outSet.push_back(*iter);
}
}
}
bool Delaunay::flipTest( TriangleVector &triSet, Triangle t )
{
bool flipped = false;
Vertex a = t.m_vertices[0];
Vertex b = t.m_vertices[1];
Vertex c = t.m_vertices[2];
TriangleVector tSet;
for (TriangleVector::iterator iter = triSet.begin();
iter != triSet.end();)
{
Vertex d;
d.m_index = -100;
// 寻找拥有相同边ab的三角形
int satisfy[3] = {0, 0, 0};
for (int j = 0, k = 1; j < Triangle::Vertex_Size; j++, k *= 2)
{
if (iter->m_vertices[j].m_index == a.m_index ||
iter->m_vertices[j].m_index == b.m_index)
{
satisfy[j] = k;
}
}
switch (satisfy[0] | satisfy[1] | satisfy[2])
{
case 3: // v2
if (Vertex::cross(a, c, iter->m_vertices[2]) != 0 &&
Vertex::cross(b, c, iter->m_vertices[2]) != 0)
{
d = iter->m_vertices[2];
}
break;
case 5: // v1
if (Vertex::cross(a, c, iter->m_vertices[1]) != 0 &&
Vertex::cross(b, c, iter->m_vertices[1]) != 0)
{
d = iter->m_vertices[1];
}
break;
case 6: // v0
if (Vertex::cross(a, c, iter->m_vertices[0]) != 0 &&
Vertex::cross(b, c, iter->m_vertices[0]) != 0)
{
d = iter->m_vertices[0];
}
break;
default:
break;
}
if (d.m_index != -100)
{
if (inCircle(a, b, c, d)) // 判断d是否在三角形abc的外接圆内
{
flipped = true;
Triangle t0(a, d, c);
Triangle t1(d, b, c);
tSet.push_back(t0);
tSet.push_back(t1);
iter = triSet.erase(iter);
break;
}
else
{
iter++;
}
}
else
{
iter++;
}
}
for (int i = 0; i < tSet.size(); i++)
{
if (!flipTest(triSet, tSet[i]))
{
triSet.push_back(tSet[i]);
}
}
return flipped;
}
void Delaunay::insertVertex( TriangleVector &triSet, const Vertex &v )
{
TriangleVector tmp;
for (TriangleVector::iterator iter = triSet.begin();
iter != triSet.end();)
{
int r = iter->inTriangle(v); // 判断点是否在三角形内
// cout << iter->m_vertices[0].m_xyz
// << iter->m_vertices[1].m_xyz
// << iter->m_vertices[2].m_xyz << endl;
switch (r)
{
case 0: // in
{
Triangle t0(iter->m_vertices[0], iter->m_vertices[1], v);
Triangle t1(iter->m_vertices[1], iter->m_vertices[2], v);
Triangle t2(iter->m_vertices[2], iter->m_vertices[0], v);
tmp.push_back(t0);
tmp.push_back(t1);
tmp.push_back(t2);
iter = triSet.erase(iter);
}
break;
case -1: // on v0v1
{
Triangle t0(iter->m_vertices[1], iter->m_vertices[2], v);
Triangle t1(iter->m_vertices[2], iter->m_vertices[0], v);
tmp.push_back(t0);
tmp.push_back(t1);
iter = triSet.erase(iter);
}
break;
case -2: // on v1v2
{
Triangle t0(iter->m_vertices[0], iter->m_vertices[1], v);
Triangle t1(iter->m_vertices[2], iter->m_vertices[0], v);
tmp.push_back(t0);
tmp.push_back(t1);
iter = triSet.erase(iter);
}
break;
case -3: // on v2v0
{
Triangle t0(iter->m_vertices[0], iter->m_vertices[1], v);
Triangle t1(iter->m_vertices[1], iter->m_vertices[2], v);
tmp.push_back(t0);
tmp.push_back(t1);
iter = triSet.erase(iter);
}
break;
default:
iter++;
break;
}
if (r <= 0)
{
break;
}
}
for (int i = 0; i < tmp.size(); i++)
{
if (!flipTest(triSet, tmp[i])) // 优化delaunay三角
{
triSet.push_back(tmp[i]);
}
/* drawTrianglesOnPlane(triSet);*/
}
}
