public void DistanceAndFrustumCulling(CameraFrustum frustum)
{
var viewPoint = frustum.ViewPoint;
var halfSize = _clusterDimensions / 2;
var minVisiblePosX = viewPoint.x - _cullingDistance;
var minVisiblePosZ = viewPoint.z - _cullingDistance;
var maxVisiblePosX = minVisiblePosX + _cullingDistance * 2;
var maxVisiblePosZ = minVisiblePosZ + _cullingDistance * 2;
int curVisibleStartX = Mathf.FloorToInt(minVisiblePosX / _clusterSize) + halfSize;
int curVisibleStartZ = Mathf.FloorToInt(minVisiblePosZ / _clusterSize) + halfSize;
int curVisibleEndX = Mathf.CeilToInt(maxVisiblePosX / _clusterSize) + halfSize;
int curVisibleEndZ = Mathf.CeilToInt(maxVisiblePosZ / _clusterSize) + halfSize;
bool enoughRoom = true;
for (int i = _lastVisibleStartX; i < _lastVisibleEndX; ++i)
{
for (int j = _lastVisibleStartZ; j < _lastVisibleEndZ; ++j)
{
if (i >= 0 && i < _clusterDimensions && j >= 0 && j < _clusterDimensions)
{
var cluster = _nodeClusters[i, j];
if (cluster == null)
{
continue;
}
var node = cluster.DistanceAndFrustumCulling(viewPoint, enoughRoom);
if (node != null && enoughRoom)
{
_curInstantiatingNode = node;
enoughRoom = false;
}
}
}
}
if (_lastVisibleStartX != curVisibleStartX || _lastVisibleEndX != curVisibleEndX ||
_lastVisibleStartZ != curVisibleStartZ || _lastVisibleEndZ != curVisibleEndZ)
{
for (int i = curVisibleStartX; i < curVisibleEndX; ++i)
{
for (int j = curVisibleStartZ; j < curVisibleEndZ; ++j)
{
if (i >= 0 && i < _clusterDimensions && j >= 0 && j < _clusterDimensions)
{
var cluster = _nodeClusters[i, j];
if (cluster == null)
{
continue;
}
var node = cluster.DistanceAndFrustumCulling(viewPoint, enoughRoom);
if (node != null && enoughRoom)
{
_curInstantiatingNode = node;
enoughRoom = false;
}
}
}
}
_lastVisibleStartX = curVisibleStartX;
_lastVisibleEndX = curVisibleEndX;
_lastVisibleStartZ = curVisibleStartZ;
_lastVisibleEndZ = curVisibleEndZ;
}
if (!enoughRoom)
{
_curInstantiatingNode.SetInstantiating();
_curInstantiatingNode.Node.BuildBuffer(_curInstantiatingNode.HeightBuffer());
}
var count = _cachedNodes.Length;
for (int i = 0; i < count; ++i)
{
var node = _cachedNodes[i];
if (node != null && node.IsInstantiated)
{
node.IsActive = frustum.IsDetailNodeVisible(node.Mins, node.Maxs);
}
}
}
