// adjust balance for a double rotate left
void AVLTreeIndex::adjustRL(AVLTreeNode *last, AVLTreeNode *first)
{
if (last == root) last->balance = balanced;
else if (first->key > last->parent->key) {
last->balance = biasleft;
adjustBalance(last->parent->right, first);
} else {
last->balance = balanced;
last->parent->right->balance = biasright;
adjustBalance(last, first);
}
}
void DSP::read(signed channel[]) {
adjustVolume();
adjustBalance();
for(unsigned c = 0; c < settings.channels; c++) {
channel[c] = clamp(settings.precision, output.read(c) * settings.intensity);
}
output.rdoffset++;
}
void AVLTreeIndex::restoreBalance(AVLTreeNode *parent, AVLTreeNode *newNode)
{
// case 1: parent DNE, newNode unbalances
if (parent == NULL) {
if (newNode->key < root->key) root->balance = biasleft; // newNode inserted left of root
else root->balance = biasright; // newNode inserted right of root
adjustBalance(root, newNode);
}
// case 2: insertion of newNode in opposite subtree of parent, balances parent
else if (((parent->balance == biasleft) && (newNode->key.compare(parent->key) > 0)) ||
((parent->balance == biasright) && (newNode->key.compare(parent->key) < 0))) {
parent->balance = balanced;
adjustBalance(parent, newNode);
}
// case 3: insertion of newNode in right child of parent
else if (parent->balance == biasright) {
if (newNode->key > parent->right->key) { // insertion into right subtree of right child, single rotation left
parent->balance = balanced;
rotateLeft(parent);
adjustBalance(parent->parent, newNode);
} else if (newNode->key < parent->right->key) { // insertion into left subtree of right child, double rotation left
rotateRight(parent->right);
rotateLeft(parent);
adjustRL(parent, newNode);
}
}
// case 4: insertion of newNode in left child of parent
else if (parent->balance == biasleft) {
if (newNode->key < parent->left->key) { // insertion into left subtree of left child, single rotation right
parent->balance = balanced;
rotateRight(parent);
adjustBalance(parent->parent, newNode);
} else if (newNode->key < parent->right->key) { // insertion into right subtree of left child, double rotation right
rotateLeft(parent->left);
rotateRight(parent);
adjustLR(parent, newNode);
}
}
}
static TNode *insertBalance(TNode *root, int dir) {
TNode *n = root->link[dir];
int bal = (dir == 0) ? -1 : +1;
if (n->balance == bal) {
root->balance = n->balance = 0;
root = singleRotate(root, !dir);
} else { /* n->balance == -bal */
adjustBalance(root, dir, bal);
root = doubleRotate(root, !dir);
}
return root;
}
static TNode *removeBalance(TNode *root, int dir, int *done) {
TNode *n = root->link[!dir];
int bal = (dir == 0) ? -1 : +1;
if (n->balance == -bal) {
root->balance = n->balance = 0;
root = singleRotate(root, dir);
} else if (n->balance == bal) {
adjustBalance(root, !dir, -bal);
root = doubleRotate(root, dir);
} else { /* n->balance == 0 */
root->balance = -bal;
n->balance = bal;
root = singleRotate(root, dir);
*done = 1;
}
return root;
}
