Crash when too many units are moving

[Igoorx]

At some point, when too many units are moving, the game tries to allocate a pathfinder cell info but crashes because the info pool is empty. I encountered this crash while spamming "Angry Mob". It happened in the file AIPathfind.cpp, in the following section:

if (found) {
    return;
}

newCell->allocateInfo(scanCell);
if (!newCell->getClosed() && !newCell->getOpen()) {
    m_closedList = newCell->putOnClosedList(m_closedList);
}

adjNewCell->allocateInfo(adjacentCell);
cellCount++;
Int curCost = adjNewCell->costToHierGoal(parentCell);
Int remCost = adjNewCell->costToHierGoal(goalCell);
if (adjNewCell->getPinched() || newCell->getPinched()) {

Link

A possible fix could be to return early if allocateInfo fails, which is already done in other places that use allocateInfo. For example:

if (!newCell->allocateInfo(scanCell)) {
    // Out of cells for pathing...
    return;
}
if (!newCell->getClosed() && !newCell->getOpen()) {
    m_closedList = newCell->putOnClosedList(m_closedList);
}

if (!adjNewCell->allocateInfo(adjacentCell)) {
    // Out of cells for pathing...
    return;
}

Alternatively, increasing the size of the cell info pool is also possible, but there needs to be a sane limit for that.

[DevGeniusCode]

• Related Game crashes when a lot of units are being moved at once #81

[sorcerer86pt]

so to test this what? spam angry mob (20 units? ) and then make them move somewhere?

[simplenotezy]

Could we improve the underlying API so that the code does not crash at all if the pool is empty? That way no implementations had to change, and possible other edge cases could be fixed in one go.