private void SetInstanceVertexBufferData()
{
// VB.SetData(T[]) can only be used with an array of T[] (not IList<T>).
// If Instances is not a T[], then we have to copy it into an array. We
// use a static shared array to avoid garbage. Only one thread can access
// this array at a time.
var array = Instances as T[];
if (array == null)
{
// Setting SharedArray is not protected because if two threads set it in parallel,
// we only create garbage.
lock (SharedArrayLock)
{
array = SharedArray;
if (array == null || array.Length < Instances.Count)
{
array = new T[(int)MathHelper.NextPowerOf2((uint)Instances.Count - 1)];
SharedArray = array;
}
Instances.CopyTo(array, 0);
}
}
var dynamicInstanceVertexBuffer = _instanceVertexBuffer as DynamicVertexBuffer;
if (dynamicInstanceVertexBuffer != null)
{
dynamicInstanceVertexBuffer.SetData(array, 0, Instances.Count, SetDataOptions.Discard);
}
else
{
_instanceVertexBuffer.SetData(array, 0, Instances.Count);
}
}
