void LayerTriangulation::triangulate1(int layer0, int layer1, const std::vector<Point2D> &points)
{
std::vector<int> &idx0 = layers[layer0];
std::vector<int> &idx1 = layers[layer1];
int point0 = lowest[layer0], point1 = 0;
real min_dist = distance(points[idx0[point0]], points[idx1[point1]]);
for (int index = 1; index < idx1.size(); ++index) {
real dist = distance(points[idx0[point0]], points[idx1[index]]);
if (dist < min_dist) {
point1 = index;
min_dist = dist;
}
}
int end0 = point0, end1 = point1;
do {
edges.push_back(std::make_pair(idx0[point0], idx1[point1]));
int next0 = (point0 + 1) % idx0.size(), next1 = (point1 + 1) % idx1.size();
if ((point0 == end0 && next1 == end1 && idx1.size() > 1) || (point1 == end1 && next0 == end0))
break;
if (!is_ccw(points[idx0[point0]], points[idx1[point1]], points[idx1[next1]])) {
// Check if we can build next triangle
if (!is_ccw(points[idx0[next0]], points[idx1[point1]], points[idx1[next1]])) {
// Check triangle with minimum angle
real angle0 = std::min(min_angle(points[idx0[point0]], points[idx1[point1]], points[idx1[next1]]),
min_angle(points[idx0[point0]], points[idx1[next1]], points[idx0[next0]]));
real angle1 = std::min(min_angle(points[idx0[point0]], points[idx0[next0]], points[idx1[point1]]),
min_angle(points[idx0[next0]], points[idx1[next1]], points[idx1[point1]]));
if (angle0 > angle1) {
point1 = next1;
} else {
point0 = next0;
}
} else {
point1 = next1;
}
} else {
point0 = next0;
}
} while (point0 != end0 || point1 != end1);
}
void LayerTriangulation::grahamScan0(const std::vector<int> &indices, const std::vector<Point2D> &points, std::vector<int> &inner)
{
if (indices.size() == 0)
return;
layers.push_back(std::vector<int>());
std::vector<int> &layer = layers.back();
if (indices.size() < 3) {
for (int index : indices)
layer.push_back(index);
} else if (indices.size() == 3) {
layer.push_back(indices[0]);
layer.push_back(indices[1]);
layer.push_back(indices[2]);
} else {
std::vector<bool> mask(indices.size(), false);
layer.reserve(indices.size());
layer.push_back(0);
layer.push_back(1);
layer.push_back(2);
for (size_t index = 3; index < indices.size(); ++index) {
int prev_index = layer.back(); layer.pop_back();
while (!is_ccw(points[indices[layer.back()]], points[indices[prev_index]], points[indices[index]])) {
mask[prev_index] = true;
prev_index = layer.back();
layer.pop_back();
}
layer.push_back(prev_index);
layer.push_back(index);
}
for (size_t index = 0; index < layer.size(); ++index) {
layer[index] = indices[layer[index]];
}
inner.push_back(indices[0]);
for (size_t index = 0; index < mask.size(); ++index) {
if (mask[index])
inner.push_back(indices[index]);
}
}
}
void LayerTriangulation::triangulate0(int layer0, int layer1, const std::vector<Point2D> &points)
{
int point0 = lowest[layer0];
int point1 = lowest[layer1];
std::vector<int> &idx0 = layers[layer0];
std::vector<int> &idx1 = layers[layer1];
do {
edges.push_back(std::make_pair(idx0[point0], idx1[point1]));
if (!is_ccw(points[idx0[point0]], points[idx1[point1]], points[idx1[(point1 + 1) % idx1.size()]])) {
point1 = (point1 + 1) % idx1.size();
} else {
point0 = (point0 + 1) % idx0.size();
}
} while (point0 != lowest[layer0] || point1 != lowest[layer1]);
}
//------------------------------------------------------------------------
void vcgen_contour::rewind(unsigned)
{
if(m_status == initial)
{
m_src_vertices.close(true);
if(m_auto_detect)
{
if(!is_oriented(m_orientation))
{
m_orientation = (calc_polygon_area(m_src_vertices) > 0.0) ?
path_flags_ccw :
path_flags_cw;
}
}
if(is_oriented(m_orientation))
{
m_stroker.width(is_ccw(m_orientation) ? m_width : -m_width);
}
}
m_status = ready;
m_src_vertex = 0;
}
void LayerTriangulation::grahamScan1(const std::vector<int> &indices, const std::vector<Point2D> &points, std::vector<int> &inner)
{
if (indices.size() <= 1)
return;
layers.push_back(std::vector<int>());
std::vector<int> &layer = layers.back();
if (indices.size() < 4) {
for (size_t index = 1; index < indices.size(); ++index) {
layer.push_back(indices[index]);
}
} else if (indices.size() == 4) {
if (is_ccw(points[indices[1]], points[indices[2]], points[indices[3]])) {
layer.push_back(indices[1]);
layer.push_back(indices[2]);
layer.push_back(indices[3]);
} else {
layer.push_back(indices[1]);
layer.push_back(indices[3]);
layer.push_back(indices[2]);
}
} else {
std::deque<int> hull;
std::vector<bool> mask(indices.size(), false);
hull.push_back(0);
hull.push_back(1);
hull.push_back(2);
for (size_t index = 3; index < indices.size(); ++index) {
int prev_index = hull.back(); hull.pop_back();
while (!is_ccw(points[indices[hull.back()]], points[indices[prev_index]], points[indices[index]])) {
mask[prev_index] = true;
prev_index = hull.back();
hull.pop_back();
}
hull.push_back(prev_index);
hull.push_back(index);
}
mask[1] = true;
hull.pop_front();
for (int index = (int)indices.size() - 1; index > 0; --index) {
if (mask[index]) {
int prev_index = hull.back(); hull.pop_back();
while (!is_ccw(points[indices[hull.back()]], points[indices[prev_index]], points[indices[index]])) {
mask[prev_index] = true;
prev_index = hull.back();
hull.pop_back();
}
mask[prev_index] = false;
mask[index] = false;
hull.push_back(prev_index);
hull.push_back(index);
}
}
mask[1] = false;
hull.pop_back();
for (auto it = hull.begin(); it != hull.end(); ++it) {
layer.push_back(indices[*it]);
}
inner.push_back(indices[0]);
for (size_t index = 0; index < mask.size(); ++index) {
if (mask[index])
inner.push_back(indices[index]);
}
}
}
