Struct Table

pub struct Table { /* private fields */ }

A column-oriented structure-of-arrays based storage for Components of entities in a World.

Conceptually, a Table can be thought of as an HashMap<ComponentId, Column>, where each ThinColumn is a type-erased Vec<T: Component>. Each row corresponds to a single entity (i.e. index 3 in Column A and index 3 in Column B point to different components on the same entity). Fetching components from a table involves fetching the associated column for a component type (via its ComponentId), then fetching the entity’s row within that column.

Implementations

impl Table

pub fn entities(&self) -> &[Entity]

Fetches a read-only slice of the entities stored within the Table.

pub fn capacity(&self) -> usize

Get the capacity of this table, in entities. Note that if an allocation is in process, this might not match the actual capacity of the columns, but it should once the allocation ends.

pub unsafe fn get_data_slice_for<T>( &self, component_id: ComponentId, ) -> Option<&[UnsafeCell<T>]>

Get the data of the column matching component_id as a slice.

Safety

row.as_usize() < self.len()

• T must match the component_id

pub fn get_added_ticks_slice_for( &self, component_id: ComponentId, ) -> Option<&[UnsafeCell<Tick>]>

Get the added ticks of the column matching component_id as a slice.

pub fn get_changed_ticks_slice_for( &self, component_id: ComponentId, ) -> Option<&[UnsafeCell<Tick>]>

Get the changed ticks of the column matching component_id as a slice.

pub fn get_changed_tick( &self, component_id: ComponentId, row: TableRow, ) -> Option<&UnsafeCell<Tick>>

Get the specific change tick of the component matching component_id in row.

pub fn get_added_tick( &self, component_id: ComponentId, row: TableRow, ) -> Option<&UnsafeCell<Tick>>

Get the specific added tick of the component matching component_id in row.

pub unsafe fn get_ticks_unchecked( &self, component_id: ComponentId, row: TableRow, ) -> Option<ComponentTicks>

Get the ComponentTicks of the component matching component_id in row.

Safety

• row.as_usize() < self.len()

pub fn get_column(&self, component_id: ComponentId) -> Option<&ThinColumn>

Fetches a read-only reference to the ThinColumn for a given Component within the table.

Returns None if the corresponding component does not belong to the table.

pub fn has_column(&self, component_id: ComponentId) -> bool

Checks if the table contains a ThinColumn for a given Component.

Returns true if the column is present, false otherwise.

pub fn entity_count(&self) -> usize

Gets the number of entities currently being stored in the table.

pub fn get_drop_for( &self, component_id: ComponentId, ) -> Option<unsafe fn(_: OwningPtr<'_>)>

Get the drop function for some component that is stored in this table.

pub fn component_count(&self) -> usize

Gets the number of components being stored in the table.

pub fn entity_capacity(&self) -> usize

Gets the maximum number of entities the table can currently store without reallocating the underlying memory.

pub fn is_empty(&self) -> bool

Checks if the Table is empty or not.

Returns true if the table contains no entities, false otherwise.

pub fn iter_columns(&self) -> impl Iterator<Item = &ThinColumn>

Iterates over the ThinColumns of the Table.

pub unsafe fn get_component( &self, component_id: ComponentId, row: TableRow, ) -> Option<Ptr<'_>>

Get the component at a given row, if the Table stores components with the given component_id

Safety

row.as_usize() < self.len()

Trait Implementations

impl Drop for Table

fn drop(&mut self)

Executes the destructor for this type.