cubos::core::ecs::QueryArchetypeNode class final
#include <core/ecs/query/node/archetype.hpp>

Node which forces a given target to belong to a set of archetypes.

Base classes

class QueryNode
Query filter step, which receives an iterator and advances it until it points to a valid match.

Constructors, destructors, conversion operators

QueryArchetypeNode(int target)
Constructs.

Public functions

void with(ColumnId column)
Forces the node to match only archetypes with the given column.
void without(ColumnId column)
Forces the node to match only archetypes without the given column.
auto equivalent(const QueryArchetypeNode& other) const -> bool
Returns whether two nodes are equivalent.
auto target() const -> int
Gets the target being filtered.
auto archetypes() const -> const std::vector<ArchetypeId>&
Gets the known archetypes which match the requirements for the target.
auto estimate() const -> std::size_t override
Returns a rough estimate on how many matches this node produces by itself.
void update(World& world) override
Updates the node with new data from the given world.
auto next(World& world, TargetMask pins, Iterator& iterator) const -> bool override
Advances the iterator to the next valid match, or checks if the pinned targets are valid.

Function documentation

cubos::core::ecs::QueryArchetypeNode::QueryArchetypeNode(int target)

Constructs.

Parameters
target Target.

bool cubos::core::ecs::QueryArchetypeNode::equivalent(const QueryArchetypeNode& other) const

Returns whether two nodes are equivalent.

Parameters
other Other node.

std::size_t cubos::core::ecs::QueryArchetypeNode::estimate() const override

Returns a rough estimate on how many matches this node produces by itself.

Nodes are sorted by this value to minimize the number of iterations. It makes more sense to first run the node which produces the fewest matches, as it will be the most selective.

void cubos::core::ecs::QueryArchetypeNode::update(World& world) override

Updates the node with new data from the given world.

Parameters
world World.

bool cubos::core::ecs::QueryArchetypeNode::next(World& world, TargetMask pins, Iterator& iterator) const override

Advances the iterator to the next valid match, or checks if the pinned targets are valid.

Parameters
world World being queried.
pins Whether each target is pinned.
iterator Iterator.
Returns Whether a match was found.

Operates in two different modes:

  • Iterate: at least one of the node targets is not pinned.
  • Validate: all node targets are already pinned.

When iterating, this function should receive an iterator with the cursor index set to SIZE_MAX, or one previously returned by this function. It will update the iterator's cursor index and row to point to the first or next valid match. The relevant target archetypes and cursor rows will be set for any newly pinned targets.

When validating, the function will only check if the pinned targets match the requirements and return true or false without modifying the iterator. The passed iterator should have the pinned targets' archetypes and cursor rows set.