bubel-ecs/source/ecs/entity_allocator.d

module ecs.entity_allocator;

enum bucketSize = 4096;
enum bucketsInAllocation = 128;

struct Bucket
{
    union
    {
        ubyte[bucketSize] memory;
        Bucket* next;
    }

}

struct BucketArray
{
    Bucket[bucketsInAllocation] buckets;
}

struct EntityAllocator
{
    BucketArray[] arrays;
    Bucket* lastEmptyBucket;

    Bucket* initBucketArray(ref BucketArray bArr)
    {
        return null;
    }

    void allocateBucketArray()
    {
        //auto bucketArray = new BucketArray();
        BucketArray bucketArray;
        assert(cast(uint)bucketArray.buckets[0].memory.ptr % bucketSize == 0);
        arrays ~= bucketArray;
        Bucket* lasBucket = initBucketArray(bucketArray);
        lastEmptyBucket = lasBucket;
    }

    void allocateBucket()
    {
        
    }

    ubyte[] getMemory()
    {
        if (lastEmptyBucket is null)
        {
            allocateBucket();
        }
        auto bucketTmp = lastEmptyBucket;
        lastEmptyBucket = bucketTmp.next;

        return bucketTmp.memory[];
    }

}