void LiveWireDP(int seedX, int seedY, Node* nodes, int width, int height, const unsigned char* selection, int numExpanded)
{
CTypedPtrHeap<Node> pq;
for (int i=0;i<width*height;i++){ nodes[i].state = INITIAL; }
NODE(nodes, seedX, seedY, width).totalCost = 0;
NODE(nodes, seedX, seedY, width).prevNode = NULL;
pq.Insert(&NODE(nodes,seedX,seedY,width));
Node* cur;
int dx, dy;
while (!pq.IsEmpty() && numExpanded > 0){
cur = pq.ExtractMin();
cur->state = EXPANDED;
for(int i=0;i<8;i++){
cur->nbrNodeOffset( dx, dy, i);
int x2 = cur->column+dx;
int y2 = cur->row + dy;
if (x2 > -1 && x2 < width && y2 > -1 && y2 < height && (selection == NULL || selection[y2*width+x2])){
Node* n = &NODE(nodes, cur->column + dx, cur->row + dy, width);
int v = cur->totalCost + cur->linkCost[i];
switch(n->state){
case INITIAL:
n->totalCost = v;
n->state = ACTIVE;
n->prevNode = cur;
pq.Insert(n);
break;
case ACTIVE:
if (n->totalCost > v) {
n->totalCost = v;
n->prevNode = cur;
pq.Update(n);
}
break;
}
}
}
}
}
void LiveWireDP(int seedX, int seedY, Node *nodes, int width, int height, const unsigned char *selection, int numExpanded)
{
CTypedPtrHeap<Node> priorityQueue;
Node *curNode = nodes + seedY*width + seedX;
int expandedCount = 0;
//Initialize all nodes
for (int i = 0; i < width * height; i++)
{
nodes[i].state = INITIAL;
}
curNode->totalCost = 0.;
curNode->prevNode = NULL;
priorityQueue.Insert(curNode);
while (!priorityQueue.IsEmpty())
{
// remove selected node from the running
// and expand it
curNode = priorityQueue.ExtractMin();
curNode->state = EXPANDED;
if (++expandedCount == numExpanded)
{
return;
}
//iterate across neighbors
for (int linkIndex = 0; linkIndex < 8; linkIndex++)
{
int offsetX, offsetY;
curNode->nbrNodeOffset(offsetX, offsetY, linkIndex);
int xPosition = curNode->column + offsetX;
int yPosition = curNode->row + offsetY;
if (xPosition < 0 || xPosition >= width || yPosition < 0 || yPosition >= height)
{
continue;
}
if (selection == NULL || selection[yPosition*width+xPosition] == 1)
{
Node *tempNode = &nodes[yPosition*width+xPosition];
if (tempNode->state == INITIAL)
{
tempNode->totalCost = curNode->totalCost + curNode->linkCost[linkIndex];
tempNode->state = ACTIVE;
tempNode->prevNode = curNode;
priorityQueue.Insert(tempNode);
}
else if(tempNode->state == ACTIVE)
{
if (curNode->totalCost + curNode->linkCost[linkIndex] < tempNode->totalCost)
{
tempNode->prevNode = curNode;
priorityQueue.Update(tempNode);
}
}
else
{
continue;
}
}
}
}
}
