Merge branch 'use_new_btree' into 'master'

Use new BoxTree, activate search tree in STLBoundary

See merge request jschoeberl/netgen!259
This commit is contained in:
Joachim Schöberl 2019-10-01 10:54:42 +00:00
commit a4c7ea24b5
5 changed files with 374 additions and 389 deletions

View File

@ -741,89 +741,355 @@ public:
const ADTree3 & Tree() const { return *tree; };
};
template<int dim, typename T=INDEX>
class BoxTree
{
public:
// Number of entries per leaf
static constexpr int N = 100;
template <int dim, typename T = INDEX>
class BoxTree
struct Node;
struct Leaf
{
T_ADTree<2*dim,T> * tree;
Point<dim> boxpmin, boxpmax;
public:
BoxTree (const Box<dim> & abox)
Point<2*dim> p[N];
T index[N];
int n_elements;
Leaf() : n_elements(0)
{ }
void Add( ClosedHashTable<T, Leaf*> &leaf_index, const Point<2*dim> &ap, T aindex )
{
p[n_elements] = ap;
index[n_elements] = aindex;
n_elements++;
leaf_index[aindex] = this;
}
};
struct Node
{
union
{
boxpmin = abox.PMin();
boxpmax = abox.PMax();
Node *children[2];
Leaf *leaf;
};
double sep;
int level;
Node()
: children{nullptr,nullptr}
{ }
~Node()
{ }
Leaf *GetLeaf() const
{
return children[1] ? nullptr : leaf;
}
};
private:
Node root;
ClosedHashTable<T, Leaf*> leaf_index;
Point<dim> global_min, global_max;
double tol;
size_t n_leaves;
size_t n_nodes;
BlockAllocator ball_nodes;
BlockAllocator ball_leaves;
public:
BoxTree (const Point<dim> & pmin, const Point<dim> & pmax)
: global_min(pmin), global_max(pmax), n_leaves(1), n_nodes(1), ball_nodes(sizeof(Node)), ball_leaves(sizeof(Leaf))
{
root.leaf = (Leaf*) ball_leaves.Alloc(); new (root.leaf) Leaf();
root.level = 0;
tol = 1e-7 * Dist(pmax, pmin);
}
BoxTree (const Box<dim> & box)
: BoxTree(box.PMin(), box.PMax())
{ }
size_t GetNLeaves()
{
return n_leaves;
}
size_t GetNNodes()
{
return n_nodes;
}
template<typename TFunc>
void GetFirstIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
TFunc func=[](auto pi){return false;}) const
{
// static Timer timer("BoxTree::GetIntersecting"); RegionTimer rt(timer);
// static Timer timer1("BoxTree::GetIntersecting-LinearSearch");
ArrayMem<const Node*, 100> stack;
ArrayMem<int, 100> dir_stack;
Point<2*dim> tpmin, tpmax;
for (int i = 0; i < dim; i++)
for (size_t i : IntRange(dim))
{
tpmin(i) = tpmin(i+dim) = boxpmin(i);
tpmax(i) = tpmax(i+dim) = boxpmax(i);
tpmin(i) = global_min(i);
tpmax(i) = pmax(i)+tol;
tpmin(i+dim) = pmin(i)-tol;
tpmax(i+dim) = global_max(i);
}
tree = new T_ADTree<2*dim,T> (tpmin, tpmax);
}
BoxTree (const Point<dim> & apmin, const Point<dim> & apmax)
{
boxpmin = apmin;
boxpmax = apmax;
Point<2*dim> tpmin, tpmax;
for (int i = 0; i < dim; i++)
stack.SetSize(0);
stack.Append(&root);
dir_stack.SetSize(0);
dir_stack.Append(0);
while(stack.Size())
{
tpmin(i) = tpmin(i+dim) = boxpmin(i);
tpmax(i) = tpmax(i+dim) = boxpmax(i);
const Node *node = stack.Last();
stack.DeleteLast();
int dir = dir_stack.Last();
dir_stack.DeleteLast();
if(Leaf *leaf = node->GetLeaf())
{
// RegionTimer rt1(timer1);
for (auto i : IntRange(leaf->n_elements))
{
bool intersect = true;
const auto p = leaf->p[i];
for (int d = 0; d < dim; d++)
if (p[d] > tpmax[d])
intersect = false;
for (int d = dim; d < 2*dim; d++)
if (p[d] < tpmin[d])
intersect = false;
if(intersect)
if(func(leaf->index[i])) return;
}
}
else
{
int newdir = dir+1;
if(newdir==2*dim) newdir = 0;
if (tpmin[dir] <= node->sep)
{
stack.Append(node->children[0]);
dir_stack.Append(newdir);
}
if (tpmax[dir] >= node->sep)
{
stack.Append(node->children[1]);
dir_stack.Append(newdir);
}
}
}
tree = new T_ADTree<2*dim,T> (tpmin, tpmax);
}
~BoxTree ()
void GetIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
NgArray<T> & pis) const
{
delete tree;
pis.SetSize(0);
GetFirstIntersecting(pmin, pmax, [&pis](auto pi) { pis.Append(pi); return false;});
}
void Insert (const Point<dim> & bmin, const Point<dim> & bmax, T pi)
{
Point<2*dim> tp;
for (size_t i = 0; i < dim; i++)
{
tp(i) = bmin(i);
tp(i+dim) = bmax(i);
}
tree->Insert (tp, pi);
}
void Insert (const Box<dim> & box, T pi)
void Insert (const Box<dim> & box, T pi)
{
Insert (box.PMin(), box.PMax(), pi);
}
void DeleteElement (T pi)
void Insert (const Point<dim> & pmin, const Point<dim> & pmax, T pi)
{
tree->DeleteElement(pi);
// static Timer timer("BoxTree::Insert"); RegionTimer rt(timer);
int dir = 0;
Point<2*dim> p;
for (auto i : IntRange(dim))
{
p(i) = pmin[i];
p(i+dim) = pmax[i];
}
Node * node = &root;
Leaf * leaf = node->GetLeaf();
// search correct leaf to add point
while(!leaf)
{
node = p[dir] < node->sep ? node->children[0] : node->children[1];
dir++;
if(dir==2*dim) dir = 0;
leaf = node->GetLeaf();
}
// add point to leaf
if(leaf->n_elements < N)
leaf->Add(leaf_index, p,pi);
else // assume leaf->n_elements == N
{
// add two new nodes and one new leaf
int n_elements = leaf->n_elements;
ArrayMem<double, N> coords(n_elements);
ArrayMem<int, N> order(n_elements);
// separate points in two halves, first sort all coordinates in direction dir
for (auto i : IntRange(n_elements))
{
order[i] = i;
coords[i] = leaf->p[i][dir];
}
QuickSortI(coords, order);
int isplit = N/2;
Leaf *leaf1 = (Leaf*) ball_leaves.Alloc(); new (leaf1) Leaf();
Leaf *leaf2 = (Leaf*) ball_leaves.Alloc(); new (leaf2) Leaf();
for (auto i : order.Range(isplit))
leaf1->Add(leaf_index, leaf->p[i], leaf->index[i] );
for (auto i : order.Range(isplit, N))
leaf2->Add(leaf_index, leaf->p[i], leaf->index[i] );
Node *node1 = (Node*) ball_nodes.Alloc(); new (node1) Node();
node1->leaf = leaf1;
node1->level = node->level+1;
Node *node2 = (Node*) ball_nodes.Alloc(); new (node2) Node();
node2->leaf = leaf2;
node2->level = node->level+1;
node->children[0] = node1;
node->children[1] = node2;
node->sep = 0.5 * (leaf->p[order[isplit-1]][dir] + leaf->p[order[isplit]][dir]);
// add new point to one of the new leaves
if (p[dir] < node->sep)
leaf1->Add( leaf_index, p, pi );
else
leaf2->Add( leaf_index, p, pi );
ball_leaves.Free(leaf);
n_leaves++;
n_nodes+=2;
}
}
void GetIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
NgArray<T> & pis) const
void DeleteElement (T pi)
{
Point<2*dim> tpmin, tpmax;
double tol = Tolerance();
for (size_t i = 0; i < dim; i++)
// static Timer timer("BoxTree::DeleteElement"); RegionTimer rt(timer);
Leaf *leaf = leaf_index[pi];
leaf_index.Delete(pi);
auto & n_elements = leaf->n_elements;
auto & index = leaf->index;
auto & p = leaf->p;
for (auto i : IntRange(n_elements))
{
tpmin(i) = boxpmin(i);
tpmax(i) = pmax(i)+tol;
tpmin(i+dim) = pmin(i)-tol;
tpmax(i+dim) = boxpmax(i);
if(index[i] == pi)
{
n_elements--;
if(i!=n_elements)
{
index[i] = index[n_elements];
p[i] = p[n_elements];
}
return;
}
}
tree->GetIntersecting (tpmin, tpmax, pis);
}
double Tolerance() const { return 1e-7 * Dist(boxpmax, boxpmin); } // single precision
const auto & Tree() const { return *tree; };
auto & Tree() { return *tree; };
};
};
// template <int dim, typename T = INDEX>
// class BoxTree
// {
// T_ADTree<2*dim,T> * tree;
// Point<dim> boxpmin, boxpmax;
// public:
// BoxTree (const Box<dim> & abox)
// {
// boxpmin = abox.PMin();
// boxpmax = abox.PMax();
// Point<2*dim> tpmin, tpmax;
// for (int i = 0; i < dim; i++)
// {
// tpmin(i) = tpmin(i+dim) = boxpmin(i);
// tpmax(i) = tpmax(i+dim) = boxpmax(i);
// }
// tree = new T_ADTree<2*dim,T> (tpmin, tpmax);
// }
//
// BoxTree (const Point<dim> & apmin, const Point<dim> & apmax)
// {
// boxpmin = apmin;
// boxpmax = apmax;
// Point<2*dim> tpmin, tpmax;
// for (int i = 0; i < dim; i++)
// {
// tpmin(i) = tpmin(i+dim) = boxpmin(i);
// tpmax(i) = tpmax(i+dim) = boxpmax(i);
// }
// tree = new T_ADTree<2*dim,T> (tpmin, tpmax);
// }
//
// ~BoxTree ()
// {
// delete tree;
// }
//
// void Insert (const Point<dim> & bmin, const Point<dim> & bmax, T pi)
// {
// Point<2*dim> tp;
//
// for (size_t i = 0; i < dim; i++)
// {
// tp(i) = bmin(i);
// tp(i+dim) = bmax(i);
// }
//
// tree->Insert (tp, pi);
// }
//
// void Insert (const Box<dim> & box, T pi)
// {
// Insert (box.PMin(), box.PMax(), pi);
// }
//
// void DeleteElement (T pi)
// {
// tree->DeleteElement(pi);
// }
//
// void GetIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
// NgArray<T> & pis) const
// {
// Point<2*dim> tpmin, tpmax;
// double tol = Tolerance();
// for (size_t i = 0; i < dim; i++)
// {
// tpmin(i) = boxpmin(i);
// tpmax(i) = pmax(i)+tol;
//
// tpmin(i+dim) = pmin(i)-tol;
// tpmax(i+dim) = boxpmax(i);
// }
//
// tree->GetIntersecting (tpmin, tpmax, pis);
// }
//
//
// double Tolerance() const { return 1e-7 * Dist(boxpmax, boxpmin); } // single precision
// const auto & Tree() const { return *tree; };
// auto & Tree() { return *tree; };
// };
}

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@ -5,265 +5,6 @@
namespace netgen
{
template<int dim, typename T=INDEX>
class BTree
{
public:
// Number of entries per leaf
static constexpr int N = 100;
struct Node;
struct Leaf
{
Point<2*dim> p[N];
T index[N];
int n_elements;
Leaf() : n_elements(0) {}
void Add( Array<Leaf*, INDEX> &leaf_index, const Point<2*dim> &ap, T aindex )
{
p[n_elements] = ap;
index[n_elements] = aindex;
n_elements++;
if(leaf_index.Size()<=aindex)
leaf_index.SetSize(2*aindex);
leaf_index[aindex] = this;
}
};
struct Node
{
union
{
Node *children[2];
Leaf *leaf;
};
double sep;
int level;
Node()
: children{nullptr,nullptr}
{ }
~Node()
{ }
Leaf *GetLeaf() const
{
return children[1] ? nullptr : leaf;
}
};
private:
Node root;
Array<Leaf*, INDEX> leaf_index;
Point<dim> global_min, global_max;
double tol;
size_t n_leaves;
size_t n_nodes;
BlockAllocator ball_nodes;
BlockAllocator ball_leaves;
public:
BTree (const Point<dim> & pmin, const Point<dim> & pmax)
: global_min(pmin), global_max(pmax), n_leaves(1), n_nodes(1), ball_nodes(sizeof(Node)), ball_leaves(sizeof(Leaf))
{
root.leaf = (Leaf*) ball_leaves.Alloc(); new (root.leaf) Leaf();
root.level = 0;
tol = 1e-7 * Dist(pmax, pmin);
}
size_t GetNLeaves()
{
return n_leaves;
}
size_t GetNNodes()
{
return n_nodes;
}
template<typename TFunc>
void GetFirstIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
TFunc func=[](auto pi){return false;}) const
{
// static Timer timer("BTree::GetIntersecting"); RegionTimer rt(timer);
// static Timer timer1("BTree::GetIntersecting-LinearSearch");
static Array<const Node*> stack(1000);
static Array<int> dir_stack(1000);
Point<2*dim> tpmin, tpmax;
for (size_t i : IntRange(dim))
{
tpmin(i) = global_min(i);
tpmax(i) = pmax(i)+tol;
tpmin(i+dim) = pmin(i)-tol;
tpmax(i+dim) = global_max(i);
}
stack.SetSize(0);
stack.Append(&root);
dir_stack.SetSize(0);
dir_stack.Append(0);
while(stack.Size())
{
const Node *node = stack.Last();
stack.DeleteLast();
int dir = dir_stack.Last();
dir_stack.DeleteLast();
if(Leaf *leaf = node->GetLeaf())
{
// RegionTimer rt1(timer1);
for (auto i : IntRange(leaf->n_elements))
{
bool intersect = true;
const auto p = leaf->p[i];
for (int d = 0; d < dim; d++)
if (p[d] > tpmax[d])
intersect = false;
for (int d = dim; d < 2*dim; d++)
if (p[d] < tpmin[d])
intersect = false;
if(intersect)
if(func(leaf->index[i])) return;
}
}
else
{
int newdir = dir+1;
if(newdir==2*dim) newdir = 0;
if (tpmin[dir] <= node->sep)
{
stack.Append(node->children[0]);
dir_stack.Append(newdir);
}
if (tpmax[dir] >= node->sep)
{
stack.Append(node->children[1]);
dir_stack.Append(newdir);
}
}
}
}
void GetIntersecting (const Point<dim> & pmin, const Point<dim> & pmax,
NgArray<T> & pis) const
{
pis.SetSize(0);
GetFirstIntersecting(pmin, pmax, [&pis](auto pi) { pis.Append(pi); return false;});
}
void Insert (const Point<dim> & pmin, const Point<dim> & pmax, T pi)
{
// static Timer timer("BTree::Insert"); RegionTimer rt(timer);
int dir = 0;
Point<2*dim> p;
for (auto i : IntRange(dim))
{
p(i) = pmin[i];
p(i+dim) = pmax[i];
}
Node * node = &root;
Leaf * leaf = node->GetLeaf();
// search correct leaf to add point
while(!leaf)
{
node = p[dir] < node->sep ? node->children[0] : node->children[1];
dir++;
if(dir==2*dim) dir = 0;
leaf = node->GetLeaf();
}
// add point to leaf
if(leaf->n_elements < N)
leaf->Add(leaf_index, p,pi);
else // assume leaf->n_elements == N
{
// add two new nodes and one new leaf
int n_elements = leaf->n_elements;
ArrayMem<double, N> coords(n_elements);
ArrayMem<int, N> order(n_elements);
// separate points in two halves, first sort all coordinates in direction dir
for (auto i : IntRange(n_elements))
{
order[i] = i;
coords[i] = leaf->p[i][dir];
}
QuickSortI(coords, order);
int isplit = N/2;
Leaf *leaf1 = (Leaf*) ball_leaves.Alloc(); new (leaf1) Leaf();
Leaf *leaf2 = (Leaf*) ball_leaves.Alloc(); new (leaf2) Leaf();
for (auto i : order.Range(isplit))
leaf1->Add(leaf_index, leaf->p[i], leaf->index[i] );
for (auto i : order.Range(isplit, N))
leaf2->Add(leaf_index, leaf->p[i], leaf->index[i] );
Node *node1 = (Node*) ball_nodes.Alloc(); new (node1) Node();
node1->leaf = leaf1;
node1->level = node->level+1;
Node *node2 = (Node*) ball_nodes.Alloc(); new (node2) Node();
node2->leaf = leaf2;
node2->level = node->level+1;
node->children[0] = node1;
node->children[1] = node2;
node->sep = 0.5 * (leaf->p[order[isplit-1]][dir] + leaf->p[order[isplit]][dir]);
// add new point to one of the new leaves
if (p[dir] < node->sep)
leaf1->Add( leaf_index, p, pi );
else
leaf2->Add( leaf_index, p, pi );
ball_leaves.Free(leaf);
n_leaves++;
n_nodes+=2;
}
}
void DeleteElement (T pi)
{
// static Timer timer("BTree::DeleteElement"); RegionTimer rt(timer);
Leaf *leaf = leaf_index[pi];
auto & n_elements = leaf->n_elements;
auto & index = leaf->index;
auto & p = leaf->p;
for (auto i : IntRange(n_elements))
{
if(index[i] == pi)
{
n_elements--;
if(i!=n_elements)
{
index[i] = index[n_elements];
p[i] = p[n_elements];
}
return;
}
}
}
};
typedef BTree<3> TBoxTree;
// typedef BoxTree<3> TBoxTree;
static const int deltetfaces[][3] =
{ { 1, 2, 3 },
{ 2, 0, 3 },
@ -486,7 +227,7 @@ namespace netgen
void AddDelaunayPoint (PointIndex newpi, const Point3d & newp,
NgArray<DelaunayTet> & tempels,
Mesh & mesh,
TBoxTree & tettree,
BoxTree<3> & tettree,
MeshNB & meshnb,
NgArray<Point<3> > & centers, NgArray<double> & radi2,
NgArray<int> & connected, NgArray<int> & treesearch,
@ -894,7 +635,7 @@ namespace netgen
pmin2 = pmin2 + 0.1 * (pmin2 - pmax2);
pmax2 = pmax2 + 0.1 * (pmax2 - pmin2);
TBoxTree tettree(pmin2, pmax2);
BoxTree<3> tettree(pmin2, pmax2);
tempels.Append (startel);

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@ -146,8 +146,6 @@ void STLGeometry :: MakeAtlas(Mesh & mesh, const MeshingParameters& mparam, cons
chartbound.Clear();
chartbound.SetChart(&chart);
chartbound.BuildSearchTree(); // different !!!
if (!found) throw Exception("Make Atlas, no starttrig found");
//find surrounding trigs
@ -324,7 +322,6 @@ void STLGeometry :: MakeAtlas(Mesh & mesh, const MeshingParameters& mparam, cons
innerchartpts.SetSize(innerchartpoints.Size());
for (size_t i = 0; i < innerchartpoints.Size(); i++)
innerchartpts[i] = GetPoint(innerchartpoints[i]);
// chartbound.BuildSearchTree(); // different !!!
// NgProfiler::StopTimer (timer2);
// NgProfiler::StartTimer (timer3);

View File

@ -1095,6 +1095,9 @@ void STLBoundary ::AddTriangle(const STLTriangle & t)
segs[1] = INDEX_2(t[1], t[2]);
segs[2] = INDEX_2(t[2], t[0]);
if(!searchtree)
BuildSearchTree();
for (auto seg : segs)
{
STLBoundarySeg bseg(seg[0], seg[1], geometry->GetPoints(), chart);
@ -1312,21 +1315,18 @@ bool STLBoundary :: TestSeg(const Point<3>& p1, const Point<3> & p2, const Vec<3
void STLBoundary :: BuildSearchTree()
{
delete searchtree;
Box<2> box2d(Box<2>::EMPTY_BOX);
Box<3> box3d = geometry->GetBoundingBox();
for (size_t i = 0; i < 8; i++)
box2d.Add ( chart->Project2d (box3d.GetPointNr(i)));
// comment to enable searchtree:
// searchtree = new BoxTree<2,INDEX_2> (box2d);
searchtree = nullptr;
searchtree = make_unique<BoxTree<2,INDEX_2>> (box2d);
// searchtree = nullptr;
}
void STLBoundary :: DeleteSearchTree()
{
delete searchtree;
searchtree = nullptr;
}
@ -1349,68 +1349,49 @@ bool STLBoundary :: TestSegChartNV(const Point3d & p1, const Point3d& p2,
Line2d l1 (p2d1, p2d2);
double eps = 1e-6;
bool ok = true;
auto hasIntersection = [&] (auto i2) NETGEN_LAMBDA_INLINE
{
const STLBoundarySeg & seg = boundary_ht[i2];
if (seg.IsSmoothEdge()) return false;
if (!box2d.Intersect (seg.BoundingBox())) return false;
const Point<2> & sp1 = seg.P2D1();
const Point<2> & sp2 = seg.P2D2();
Line2d l2 (sp1, sp2);
double lam1, lam2;
int err = CrossPointBarycentric (l1, l2, lam1, lam2);
bool in1 = (lam1 > eps) && (lam1 < 1-eps);
bool on1 = (lam1 > -eps) && (lam1 < 1 + eps);
bool in2 = (lam2 > eps) && (lam2 < 1-eps);
bool on2 = (lam2 > -eps) && (lam2 < 1 + eps);
if(!err && ((on1 && in2) || (on2 && in1)))
return true;
return false;
};
if (searchtree)
{
NgArrayMem<INDEX_2,100> pis;
searchtree -> GetIntersecting (box2d.PMin(), box2d.PMax(), pis);
for (auto i2 : pis)
{
const STLBoundarySeg & seg = boundary_ht[i2];
if (seg.IsSmoothEdge()) continue;
if (!box2d.Intersect (seg.BoundingBox())) continue;
const Point<2> & sp1 = seg.P2D1();
const Point<2> & sp2 = seg.P2D2();
Line2d l2 (sp1, sp2);
double lam1, lam2;
int err = CrossPointBarycentric (l1, l2, lam1, lam2);
bool in1 = (lam1 > eps) && (lam1 < 1-eps);
bool on1 = (lam1 > -eps) && (lam1 < 1 + eps);
bool in2 = (lam2 > eps) && (lam2 < 1-eps);
bool on2 = (lam2 > -eps) && (lam2 < 1 + eps);
if(!err && ((on1 && in2) || (on2 && in1)))
{
ok = false;
break;
}
}
bool has_intersection = false;
searchtree -> GetFirstIntersecting (box2d.PMin(), box2d.PMax(),
[&] (auto i2) NETGEN_LAMBDA_INLINE
{
has_intersection = hasIntersection(i2);
return has_intersection;
});
return !has_intersection;
}
else
{
{
for(auto [i2, seg] : boundary_ht)
{
if (seg.IsSmoothEdge()) continue;
if (!box2d.Intersect (seg.BoundingBox())) continue;
const Point<2> & sp1 = seg.P2D1();
const Point<2> & sp2 = seg.P2D2();
Line2d l2 (sp1, sp2);
double lam1, lam2;
int err = CrossPointBarycentric (l1, l2, lam1, lam2);
bool in1 = (lam1 > eps) && (lam1 < 1-eps);
bool on1 = (lam1 > -eps) && (lam1 < 1 + eps);
bool in2 = (lam2 > eps) && (lam2 < 1-eps);
bool on2 = (lam2 > -eps) && (lam2 < 1 + eps);
if(!err && ((on1 && in2) || (on2 && in1)))
{
ok = false;
break;
}
}
if(hasIntersection(i2))
return false;
return true;
}
return ok;
}

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@ -191,10 +191,10 @@ private:
const STLChart * chart;
// NgArray<STLBoundarySeg> boundary;
ClosedHashTable<INDEX_2, STLBoundarySeg> boundary_ht;
BoxTree<2,INDEX_2> * searchtree = nullptr;
unique_ptr<BoxTree<2,INDEX_2>> searchtree;
public:
STLBoundary(STLGeometry * ageometry);
~STLBoundary() { delete searchtree; }
~STLBoundary() {}
void Clear() { /* boundary.SetSize(0); */ boundary_ht = ClosedHashTable<INDEX_2,STLBoundarySeg>(); }
void SetChart (const STLChart * achart) { chart = achart; }