int
AATree<Etype>::Remove( const Etype & X, BinaryNode<Etype> * & T )
{
static int ItemFound = 0;
static BinaryNode<Etype> *DeletePtr = NullNode;
static BinaryNode<Etype> *LastPtr;
if( T != NullNode )
{
// Step 1: Search down the tree and set LastPtr and DeletePtr
LastPtr = T;
if( X < T->Element )
Remove( X, T->Left );
else
{
DeletePtr = T;
Remove( X, T->Right );
}
// Step 2: If at the bottom of the tree and
// X is present, we remove it
if( T == LastPtr )
{
if( DeletePtr != NullNode && X == DeletePtr->Element )
{
DeletePtr->Element = T->Element;
DeletePtr = NullNode;
T = T->Right;
delete LastPtr;
ItemFound = 1;
}
else
ItemFound = 0;
}
// Step 3: Otherwise, we are not at the bottom; rebalance
else
if( T->Left->Level < T->Level - 1 ||
T->Right->Level < T->Level - 1 )
{
if( T->Right->Level > --T->Level )
T->Right->Level = T->Level;
Skew( T );
Skew( T->Right );
Skew( T->Right->Right );
Split( T );
Split( T->Right );
}
}
DeletePtr = NullNode;
return ItemFound;
}
/* START: fig12_38.txt */
AATree
Remove( ElementType Item, AATree T )
{
static Position DeletePtr, LastPtr;
if( T != NullNode )
{
/* Step 1: Search down tree */
/* set LastPtr and DeletePtr */
LastPtr = T;
if( Item < T->Element )
T->Left = Remove( Item, T->Left );
else
{
DeletePtr = T;
T->Right = Remove( Item, T->Right );
}
/* Step 2: If at the bottom of the tree and */
/* item is present, we remove it */
if( T == LastPtr )
{
if( DeletePtr != NullNode &&
Item == DeletePtr->Element )
{
DeletePtr->Element = T->Element;
DeletePtr = NullNode;
T = T->Right;
free( LastPtr );
}
}
/* Step 3: Otherwise, we are not at the bottom; */
/* rebalance */
else
if( T->Left->Level < T->Level - 1 ||
T->Right->Level < T->Level - 1 )
{
if( T->Right->Level > --T->Level )
T->Right->Level = T->Level;
T = Skew( T );
T->Right = Skew( T->Right );
T->Right->Right = Skew( T->Right->Right );
T = Split( T );
T->Right = Split( T->Right );
}
}
return T;
}
/* START: fig12_36.txt */
AATree
Insert( ElementType Item, AATree T )
{
if( T == NullNode )
{
/* Create and return a one-node tree */
T = malloc( sizeof( struct AANode ) );
if( T == NULL )
FatalError( "Out of space!!!" );
else
{
T->Element = Item; T->Level = 1;
T->Left = T->Right = NullNode;
}
}
else
if( Item < T->Element )
T->Left = Insert( Item, T->Left );
else
if( Item > T->Element )
T->Right = Insert( Item, T->Right );
/* Otherwise it's a duplicate; do nothing */
T = Skew( T );
T = Split( T );
return T;
}
vec2 Line_GetNormal(line_t *l)
{
vec2 n;
n = l->v[1] - l->v[0];
n = Skew(n);
n = Normalize(n);
return n;
}
int main()
{
int Error(0);
glm::mat4 Matrix(1);
glm::vec3 Scale;
glm::quat Orientation;
glm::vec3 Translation;
glm::vec3 Skew(1);
glm::vec4 Perspective(1);
glm::decompose(Matrix, Scale, Orientation, Translation, Skew, Perspective);
return Error;
}
int
AATree<Etype>::Insert( const Etype & X, BinaryNode<Etype> * & T )
{
if( T == NullNode )
{
T = new BinaryNode<Etype>( X, NullNode, NullNode );
return 1;
}
else if( X < T->Element )
Insert( X, T->Left );
else if( T->Element < X )
Insert( X, T->Right );
else
return 0;
Skew( T );
Split( T );
return 1;
}