Ids

Functions for working with ecs_id_t. More...

Collaboration diagram for Ids:

Functions
bool	ecs_id_is_tag (const ecs_world_t *world, ecs_id_t component)
	Returns whether specified component is a tag.
bool	ecs_id_in_use (const ecs_world_t *world, ecs_id_t component)
	Returns whether specified component is in use.
ecs_entity_t	ecs_get_typeid (const ecs_world_t *world, ecs_id_t component)
	Get the type for a component.
bool	ecs_id_match (ecs_id_t component, ecs_id_t pattern)
	Utility to match a component with a pattern.
bool	ecs_id_is_pair (ecs_id_t component)
	Utility to check if component is a pair.
bool	ecs_id_is_wildcard (ecs_id_t component)
	Utility to check if component is a wildcard.
bool	ecs_id_is_any (ecs_id_t component)
	Utility to check if component is an any wildcard.
bool	ecs_id_is_valid (const ecs_world_t *world, ecs_id_t component)
	Utility to check if id is valid.
ecs_flags32_t	ecs_id_get_flags (const ecs_world_t *world, ecs_id_t component)
	Get flags associated with id.
const char *	ecs_id_flag_str (ecs_id_t component_flags)
	Convert component flag to string.
char *	ecs_id_str (const ecs_world_t *world, ecs_id_t component)
	Convert component id to string.
void	ecs_id_str_buf (const ecs_world_t *world, ecs_id_t component, ecs_strbuf_t *buf)
	Write component string to buffer.
ecs_id_t	ecs_id_from_str (const ecs_world_t *world, const char *expr)
	Convert string to a component.

Detailed Description

Functions for working with ecs_id_t.

Function Documentation

ecs_get_typeid()

ecs_entity_t ecs_get_typeid	(	const ecs_world_t *	world,
		ecs_id_t	component )

Get the type for a component.

This operation returns the type for a component id, if the id is associated with a type. For a regular component with a non-zero size (an entity with the EcsComponent component) the operation will return the component id itself.

For an entity that does not have the EcsComponent component, or with an EcsComponent value with size 0, the operation will return 0.

For a pair id the operation will return the type associated with the pair, by applying the following queries in order:

• The first pair element is returned if it is a component
• 0 is returned if the relationship entity has the Tag property
• The second pair element is returned if it is a component
• 0 is returned.

Parameters

world	The world.
component	The component.

Returns

The type of the component.

ecs_id_flag_str()

const char * ecs_id_flag_str

(

ecs_id_t

component_flags

)

Convert component flag to string.

This operation converts a component flag to a string. Possible outputs are:

• PAIR
• TOGGLE
• AUTO_OVERRIDE

Parameters

component_flags

The component flag.

Returns

The id flag string, or NULL if no valid id is provided.

ecs_id_from_str()

ecs_id_t ecs_id_from_str	(	const ecs_world_t *	world,
		const char *	expr )

Convert string to a component.

This operation is the reverse of ecs_id_str(). The FLECS_SCRIPT addon is required for this operation to work.

Parameters

world	The world.
expr	The string to convert to an id.

ecs_id_get_flags()

ecs_flags32_t ecs_id_get_flags	(	const ecs_world_t *	world,
		ecs_id_t	component )

Get flags associated with id.

This operation returns the internal flags (see api_flags.h) that are associated with the provided id.

Parameters

world	The world.
component	The component.

Returns

Flags associated with the id, or 0 if the id is not in use.

ecs_id_in_use()

bool ecs_id_in_use	(	const ecs_world_t *	world,
		ecs_id_t	component )

Returns whether specified component is in use.

This operation returns whether a component is in use in the world. A component is in use if it has been added to one or more tables.

Parameters

world	The world.
component	The component.

Returns

Whether the component is in use.

ecs_id_is_any()

bool ecs_id_is_any

(

ecs_id_t

component

)

Utility to check if component is an any wildcard.

Parameters

component

The component.

Returns

True if component is an any wildcard or a pair containing an any wildcard.

ecs_id_is_pair()

bool ecs_id_is_pair

(

ecs_id_t

component

)

Utility to check if component is a pair.

Parameters

component

The component.

Returns

True if component is a pair.

ecs_id_is_tag()

bool ecs_id_is_tag	(	const ecs_world_t *	world,
		ecs_id_t	component )

Returns whether specified component is a tag.

This operation returns whether the specified component is a tag (a component without data/size).

An id is a tag when:

• it is an entity without the EcsComponent component
• it has an EcsComponent with size member set to 0
• it is a pair where both elements are a tag
• it is a pair where the first element has the EcsPairIsTag tag

Parameters

world	The world.
component	The component.

Returns

Whether the provided id is a tag.

ecs_id_is_valid()

bool ecs_id_is_valid	(	const ecs_world_t *	world,
		ecs_id_t	component )

Utility to check if id is valid.

A valid id is an id that can be added to an entity. Invalid ids are:

• ids that contain wildcards
• ids that contain invalid entities
• ids that are 0 or contain 0 entities

Note that the same rules apply to removing from an entity, with the exception of wildcards.

Parameters

world	The world.
component	The component.

Returns

True if the id is valid.

ecs_id_is_wildcard()

bool ecs_id_is_wildcard

(

ecs_id_t

component

)

Utility to check if component is a wildcard.

Parameters

component

The component.

Returns

True if component is a wildcard or a pair containing a wildcard.

ecs_id_match()

bool ecs_id_match	(	ecs_id_t	component,
		ecs_id_t	pattern )

Utility to match a component with a pattern.

This operation returns true if the provided pattern matches the provided component. The pattern may contain a wildcard (or wildcards, when a pair).

Parameters

component	The component.
pattern	The pattern to compare with.

Returns

Whether the id matches the pattern.

ecs_id_str()

char * ecs_id_str	(	const ecs_world_t *	world,
		ecs_id_t	component )

Convert component id to string.

This operation converts the provided component id to a string. It can output strings of the following formats:

• "ComponentName"
• "FLAG|ComponentName"
• "(Relationship, Target)"
• "FLAG|(Relationship, Target)"

The PAIR flag never added to the string.

Parameters

world	The world.
component	The component to convert to a string.

Returns

The component converted to a string.

ecs_id_str_buf()

void ecs_id_str_buf	(	const ecs_world_t *	world,
		ecs_id_t	component,
		ecs_strbuf_t *	buf )

Write component string to buffer.

Same as ecs_id_str() but writes result to ecs_strbuf_t.

Parameters

world	The world.
component	The component to convert to a string.
buf	The buffer to write to.