Ejemplo n.º 1
0
        private EntityComponent ValidateItem(int index, EntityComponent item, bool isReplacing)
        {
            if (item == null)
            {
                throw new ArgumentNullException(nameof(item), @"Cannot add a null component");
            }

            var componentType = item.GetType();
            var attributes    = EntityComponentAttributes.Get(componentType);

            var onlySingleComponent = !attributes.AllowMultipleComponents;

            EntityComponent previousItem = null;

            for (int i = 0; i < Count; i++)
            {
                var existingItem = this[i];
                if (index == i && isReplacing)
                {
                    previousItem = existingItem;
                }
                else
                {
                    if (ReferenceEquals(existingItem, item))
                    {
                        throw new InvalidOperationException($"Cannot add a same component multiple times. Already set at index [{i}]");
                    }

                    if (onlySingleComponent && componentType == existingItem.GetType())
                    {
                        throw new InvalidOperationException($"Cannot add a component of type [{componentType}] multiple times");
                    }
                }
            }

            if (!AllowReplaceForeignEntity && entity != null && item.Entity != null)
            {
                throw new InvalidOperationException($"This component is already attached to entity [{item.Entity}] and cannot be attached to [{entity}]");
            }

            if (entity != null)
            {
                var transform = item as TransformComponent;
                if (transform != null)
                {
                    entity.TransformValue = transform;
                }
                else if (previousItem is TransformComponent)
                {
                    // If previous item was a transform component but we are actually replacing it, we should
                    entity.TransformValue = null;
                }

                item.Entity = entity;
            }

            return(previousItem);
        }
Ejemplo n.º 2
0
        private static EntityComponentAttributes GetInternal([NotNull] Type type)
        {
            EntityComponentAttributes attributes;

            lock (ComponentAttributes)
            {
                if (!ComponentAttributes.TryGetValue(type, out attributes))
                {
                    attributes = new EntityComponentAttributes(type.GetTypeInfo().GetCustomAttribute <AllowMultipleComponentsAttribute>() != null);
                    ComponentAttributes.Add(type, attributes);
                }
            }
            return(attributes);
        }