DSL for loading scenes, assets and configuration. More...

Collaboration diagram for Flecs script:

Classes
struct	ecs_script_var_t
	Script variable. More...

struct	ecs_script_vars_t
	Script variable scope. More...

struct	ecs_script_t
	Script object. More...

struct	EcsScript
	Script component. More...

struct	ecs_script_desc_t
	Used with ecs_script_init() More...

struct	ecs_script_expr_run_desc_t
	Used with ecs_script_expr_run(). More...

Macros
#define	FLECS_SCRIPT_H

#define	ecs_script(world, ...) ecs_script_init(world, &(ecs_script_desc_t) __VA_ARGS__)

#define	ecs_script_vars_define(vars, name, type) ecs_script_vars_define_id(vars, name, ecs_id(type))

Typedefs
typedef struct ecs_script_template_t	ecs_script_template_t

typedef struct ecs_script_var_t	ecs_script_var_t
	Script variable.

typedef struct ecs_script_vars_t	ecs_script_vars_t
	Script variable scope.

typedef struct ecs_script_t	ecs_script_t
	Script object.

typedef struct EcsScript	EcsScript
	Script component.

typedef struct ecs_script_desc_t	ecs_script_desc_t
	Used with ecs_script_init()

typedef struct ecs_script_expr_run_desc_t	ecs_script_expr_run_desc_t
	Used with ecs_script_expr_run().

Functions
FLECS_API	ECS_COMPONENT_DECLARE (EcsScript)

FLECS_API ecs_script_t *	ecs_script_parse (ecs_world_t world, const char name, const char *code)
	Parse script.

FLECS_API int	ecs_script_eval (ecs_script_t *script)
	Evaluate script.

FLECS_API void	ecs_script_free (ecs_script_t *script)
	Free script.

FLECS_API int	ecs_script_run (ecs_world_t world, const char name, const char *code)
	Parse script.

FLECS_API int	ecs_script_run_file (ecs_world_t world, const char filename)
	Parse script file.

FLECS_API int	ecs_script_ast_to_buf (ecs_script_t script, ecs_strbuf_t buf)
	Convert script AST to string.

FLECS_API char *	ecs_script_ast_to_str (ecs_script_t *script)
	Convert script AST to string.

FLECS_API ecs_entity_t	ecs_script_init (ecs_world_t world, const ecs_script_desc_t desc)
	Load managed script.

FLECS_API int	ecs_script_update (ecs_world_t world, ecs_entity_t script, ecs_entity_t instance, const char code)
	Update script with new code.

FLECS_API void	ecs_script_clear (ecs_world_t *world, ecs_entity_t script, ecs_entity_t instance)
	Clear all entities associated with script.

FLECS_API ecs_script_vars_t *	ecs_script_vars_init (ecs_world_t *world)
	Create new variable scope.

FLECS_API void	ecs_script_vars_fini (ecs_script_vars_t *vars)
	Free variable scope.

FLECS_API ecs_script_vars_t *	ecs_script_vars_push (ecs_script_vars_t *parent)
	Push new variable scope.

FLECS_API ecs_script_vars_t *	ecs_script_vars_pop (ecs_script_vars_t *vars)
	Pop variable scope.

FLECS_API ecs_script_var_t *	ecs_script_vars_declare (ecs_script_vars_t vars, const char name)
	Declare a variable.

FLECS_API ecs_script_var_t *	ecs_script_vars_define_id (ecs_script_vars_t vars, const char name, ecs_entity_t type)
	Define a variable.

FLECS_API ecs_script_var_t *	ecs_script_vars_lookup (const ecs_script_vars_t vars, const char name)
	Lookup a variable.

FLECS_API void	ecs_script_vars_from_iter (const ecs_iter_t it, ecs_script_vars_t vars, int offset)
	Convert iterator to vars This operation converts an iterator to a variable array.

FLECS_API const char *	ecs_script_expr_run (ecs_world_t world, const char ptr, ecs_value_t value, const ecs_script_expr_run_desc_t desc)
	Parse standalone expression into value.

FLECS_API char *	ecs_script_string_interpolate (ecs_world_t world, const char str, const ecs_script_vars_t *vars)
	Evaluate interpolated expressions in string.

FLECS_API char *	ecs_ptr_to_expr (const ecs_world_t world, ecs_entity_t type, const void data)
	Serialize value into expression string.

FLECS_API int	ecs_ptr_to_expr_buf (const ecs_world_t world, ecs_entity_t type, const void data, ecs_strbuf_t *buf)
	Serialize value into expression buffer.

FLECS_API char *	ecs_ptr_to_str (const ecs_world_t world, ecs_entity_t type, const void data)
	Similar as ecs_ptr_to_expr(), but serializes values to string.

FLECS_API int	ecs_ptr_to_str_buf (const ecs_world_t world, ecs_entity_t type, const void data, ecs_strbuf_t *buf)
	Serialize value into string buffer.

FLECS_API void	FlecsScriptImport (ecs_world_t *world)
	Script module import function.

Detailed Description

DSL for loading scenes, assets and configuration.

Macro Definition Documentation

◆ ecs_script

#define ecs_script	(		world,
			... ) ecs_script_init(world, &(ecs_script_desc_t) __VA_ARGS__)

Definition at line 198 of file script.h.

◆ ecs_script_vars_define

#define ecs_script_vars_define	(	vars,
		name,
		type ) ecs_script_vars_define_id(vars, name, ecs_id(type))

Definition at line 325 of file script.h.

◆ FLECS_SCRIPT_H

#define FLECS_SCRIPT_H

Definition at line 28 of file script.h.

Typedef Documentation

◆ ecs_script_template_t

typedef struct ecs_script_template_t ecs_script_template_t

Definition at line 37 of file script.h.

◆ EcsScript

typedef struct EcsScript EcsScript

Script component.

This component is added to the entities of managed scripts and templates.

Function Documentation

◆ ecs_ptr_to_expr()

FLECS_API char * ecs_ptr_to_expr	(	const ecs_world_t *	world,
		ecs_entity_t	type,
		const void *	data )

Serialize value into expression string.

This operation serializes a value of the provided type to a string. The memory pointed to must be large enough to contain a value of the used type.

Parameters

world	The world.
type	The type of the value to serialize.
data	The value to serialize.

Returns: String with expression, or NULL if failed.

◆ ecs_ptr_to_expr_buf()

FLECS_API int ecs_ptr_to_expr_buf	(	const ecs_world_t *	world,
		ecs_entity_t	type,
		const void *	data,
		ecs_strbuf_t *	buf )

Serialize value into expression buffer.

Same as ecs_ptr_to_expr(), but serializes to an ecs_strbuf_t instance.

Parameters

world	The world.
type	The type of the value to serialize.
data	The value to serialize.
buf	The strbuf to append the string to.

Returns: Zero if success, non-zero if failed.

◆ ecs_ptr_to_str()

FLECS_API char * ecs_ptr_to_str	(	const ecs_world_t *	world,
		ecs_entity_t	type,
		const void *	data )

Similar as ecs_ptr_to_expr(), but serializes values to string.

Whereas the output of ecs_ptr_to_expr() is a valid expression, the output of ecs_ptr_to_str() is a string representation of the value. In most cases the output of the two operations is the same, but there are some differences:

Strings are not quoted

Parameters

world	The world.
type	The type of the value to serialize.
data	The value to serialize.

Returns: String with result, or NULL if failed.

◆ ecs_ptr_to_str_buf()

FLECS_API int ecs_ptr_to_str_buf	(	const ecs_world_t *	world,
		ecs_entity_t	type,
		const void *	data,
		ecs_strbuf_t *	buf )

Serialize value into string buffer.

Same as ecs_ptr_to_str(), but serializes to an ecs_strbuf_t instance.

Parameters

world	The world.
type	The type of the value to serialize.
data	The value to serialize.
buf	The strbuf to append the string to.

Returns: Zero if success, non-zero if failed.

◆ ecs_script_ast_to_buf()

FLECS_API int ecs_script_ast_to_buf	(	ecs_script_t *	script,
		ecs_strbuf_t *	buf )

Convert script AST to string.

This operation converts the script abstract syntax tree to a string, which can be used to debug a script.

Parameters

script	The script.
buf	The buffer to write to.

Returns: Zero if success, non-zero if failed.

◆ ecs_script_ast_to_str()

FLECS_API char * ecs_script_ast_to_str ( ecs_script_t * script )

Convert script AST to string.

This operation converts the script abstract syntax tree to a string, which can be used to debug a script.

Parameters

script The script.

Returns: The string if success, NULL if failed.

◆ ecs_script_clear()

FLECS_API void ecs_script_clear	(	ecs_world_t *	world,
		ecs_entity_t	script,
		ecs_entity_t	instance )

Clear all entities associated with script.

Parameters

world	The world.
script	The script entity.
instance	The script instance.

◆ ecs_script_eval()

FLECS_API int ecs_script_eval ( ecs_script_t * script )

Evaluate script.

This operation evaluates (runs) a parsed script.

Parameters

script The script.

Returns: Zero if success, non-zero if failed.

◆ ecs_script_expr_run()

FLECS_API const char * ecs_script_expr_run	(	ecs_world_t *	world,
		const char *	ptr,
		ecs_value_t *	value,
		const ecs_script_expr_run_desc_t *	desc )

Parse standalone expression into value.

This operation parses a flecs expression into the provided pointer. The memory pointed to must be large enough to contain a value of the used type.

If no type and pointer are provided for the value argument, the operation will discover the type from the expression and allocate storage for the value. The allocated value must be freed with ecs_value_free().

Parameters

world	The world.
ptr	The pointer to the expression to parse.
value	The value containing type & pointer to write to.
desc	Configuration parameters for deserializer.

Returns: Pointer to the character after the last one read, or NULL if failed.

◆ ecs_script_free()

FLECS_API void ecs_script_free ( ecs_script_t * script )

Free script.

This operation frees a script object.

Templates created by the script rely upon resources in the script object, and for that reason keep the script alive until all templates created by the script are deleted.

Parameters

script The script.

◆ ecs_script_init()

FLECS_API ecs_entity_t ecs_script_init	(	ecs_world_t *	world,
		const ecs_script_desc_t *	desc )

Load managed script.

A managed script tracks which entities it creates, and keeps those entities synchronized when the contents of the script are updated. When the script is updated, entities that are no longer in the new version will be deleted.

This feature is experimental.

Parameters

world	The world.
desc	Script descriptor.

◆ ecs_script_parse()

FLECS_API ecs_script_t * ecs_script_parse	(	ecs_world_t *	world,
		const char *	name,
		const char *	code )

Parse script.

This operation parses a script and returns a script object upon success. To run the script, call ecs_script_eval().

Parameters

world	The world.
name	Name of the script (typically a file/module name).
code	The script code.

Returns: Script object if success, NULL if failed.

◆ ecs_script_run()

FLECS_API int ecs_script_run	(	ecs_world_t *	world,
		const char *	name,
		const char *	code )

Parse script.

This parses a script and instantiates the entities in the world. This operation is the equivalent to doing:

ecs_script_t *script = ecs_script_parse(world, name, code);
ecs_script_eval(script);
ecs_script_free(script);

Parameters

world	The world.
name	The script name (typically the file).
code	The script.

Returns: Zero if success, non-zero otherwise.

◆ ecs_script_run_file()

FLECS_API int ecs_script_run_file	(	ecs_world_t *	world,
		const char *	filename )

Parse script file.

This parses a script file and instantiates the entities in the world. This operation is equivalent to loading the file contents and passing it to ecs_script_run().

Parameters

world	The world.
filename	The script file name.

Returns: Zero if success, non-zero if failed.

◆ ecs_script_string_interpolate()

FLECS_API char * ecs_script_string_interpolate	(	ecs_world_t *	world,
		const char *	str,
		const ecs_script_vars_t *	vars )

Evaluate interpolated expressions in string.

This operation evaluates expressions in a string, and replaces them with their evaluated result. Supported expression formats are:

$variable_name
{expression}

The $, { and } characters can be escaped with a backslash ().

Parameters

world	The world.
str	The string to evaluate.
vars	The variables to use for evaluation.

◆ ecs_script_update()

FLECS_API int ecs_script_update	(	ecs_world_t *	world,
		ecs_entity_t	script,
		ecs_entity_t	instance,
		const char *	code )

Update script with new code.

Parameters

world	The world.
script	The script entity.
instance	An template instance (optional).
code	The script code.

◆ ecs_script_vars_declare()

FLECS_API ecs_script_var_t * ecs_script_vars_declare	(	ecs_script_vars_t *	vars,
		const char *	name )

Declare a variable.

This operation declares a new variable in the current scope. If a variable with the specified name already exists, the operation will fail.

This operation does not allocate storage for the variable. This is done to allow for variables that point to existing storage, which prevents having to copy existing values to a variable scope.

Parameters

vars	The variable scope.
name	The variable name.

Returns: The new variable, or NULL if the operation failed.

◆ ecs_script_vars_define_id()

FLECS_API ecs_script_var_t * ecs_script_vars_define_id	(	ecs_script_vars_t *	vars,
		const char *	name,
		ecs_entity_t	type )

Define a variable.

This operation calls ecs_script_vars_declare() and allocates storage for the variable. If the type has a ctor, it will be called on the new storage.

The scope's stack allocator will be used to allocate the storage. After ecs_script_vars_pop() is called on the scope, the variable storage will no longer be valid.

The operation will fail if the type argument is not a type.

Parameters

vars	The variable scope.
name	The variable name.
type	The variable type.

Returns: The new variable, or NULL if the operation failed.

◆ ecs_script_vars_fini()

FLECS_API void ecs_script_vars_fini ( ecs_script_vars_t * vars )

Free variable scope.

Free root variable scope. The provided scope should not have a parent. This operation calls ecs_script_vars_pop() on the scope.

Parameters

vars	The variable scope.

◆ ecs_script_vars_from_iter()

FLECS_API void ecs_script_vars_from_iter	(	const ecs_iter_t *	it,
		ecs_script_vars_t *	vars,
		int	offset )

Convert iterator to vars This operation converts an iterator to a variable array.

This allows for using iterator results in expressions. The operation only converts a single result at a time, and does not progress the iterator.

Iterator fields with data will be made available as variables with as name the field index (e.g. "$1"). The operation does not check if reflection data is registered for a field type. If no reflection data is registered for the type, using the field variable in expressions will fail.

Field variables will only contain single elements, even if the iterator returns component arrays. The offset parameter can be used to specify which element in the component arrays to return. The offset parameter must be smaller than it->count.

The operation will create a variable for query variables that contain a single entity.

The operation will attempt to use existing variables. If a variable does not yet exist, the operation will create it. If an existing variable exists with a mismatching type, the operation will fail.

Accessing variables after progressing the iterator or after the iterator is destroyed will result in undefined behavior.

If vars contains a variable that is not present in the iterator, the variable will not be modified.

Parameters

it	The iterator to convert to variables.
vars	The variables to write to.
offset	The offset to the current element.

◆ ecs_script_vars_init()

FLECS_API ecs_script_vars_t * ecs_script_vars_init ( ecs_world_t * world )

Create new variable scope.

Create root variable scope. A variable scope contains one or more variables. Scopes can be nested, which allows variables in different scopes to have the same name. Variables from parent scopes will be shadowed by variables in child scopes with the same name.

Use the ecs_script_vars_push() and ecs_script_vars_pop() functions to push and pop variable scopes.

When a variable contains allocated resources (e.g. a string), its resources will be freed when ecs_script_vars_pop() is called on the scope, the ecs_script_vars_t::type_info field is initialized for the variable, and ecs_type_info_t::hooks::dtor is set.

Parameters

world The world.

◆ ecs_script_vars_lookup()

FLECS_API ecs_script_var_t * ecs_script_vars_lookup	(	const ecs_script_vars_t *	vars,
		const char *	name )

Lookup a variable.

This operation looks up a variable in the current scope. If the variable can't be found in the current scope, the operation will recursively search the parent scopes.

Parameters

vars	The variable scope.
name	The variable name.

Returns: The variable, or NULL if one with the provided name does not exist.

◆ ecs_script_vars_pop()

FLECS_API ecs_script_vars_t * ecs_script_vars_pop ( ecs_script_vars_t * vars )

Pop variable scope.

This frees up the resources for a variable scope. The scope must be at the top of a vars stack. Calling ecs_script_vars_pop() on a scope that is not the last scope causes undefined behavior.

Parameters

vars	The scope to free.

Returns: The parent scope.

◆ ecs_script_vars_push()

FLECS_API ecs_script_vars_t * ecs_script_vars_push ( ecs_script_vars_t * parent )

Push new variable scope.

Scopes created with ecs_script_vars_push() must be cleaned up with ecs_script_vars_pop().

If the stack and allocator arguments are left to NULL, their values will be copied from the parent.

Parameters

parent The parent scope (provide NULL for root scope).

Returns: The new variable scope.

◆ FlecsScriptImport()

FLECS_API void FlecsScriptImport ( ecs_world_t * world )

Script module import function.

Usage:

ECS_IMPORT(world, FlecsScript)

ECS_IMPORT

#define ECS_IMPORT(world, id)

Wrapper around ecs_import().

Definition module.h:119

Parameters

world The world.

Classes

Macros

Typedefs

Functions

Detailed Description

Macro Definition Documentation

◆ ecs_script

◆ ecs_script_vars_define

◆ FLECS_SCRIPT_H

Typedef Documentation

◆ ecs_script_template_t

◆ EcsScript

Function Documentation

◆ ecs_ptr_to_expr()

◆ ecs_ptr_to_expr_buf()

◆ ecs_ptr_to_str()

◆ ecs_ptr_to_str_buf()

◆ ecs_script_ast_to_buf()

◆ ecs_script_ast_to_str()

◆ ecs_script_clear()

◆ ecs_script_eval()

◆ ecs_script_expr_run()

◆ ecs_script_free()

◆ ecs_script_init()

◆ ecs_script_parse()

◆ ecs_script_run()

◆ ecs_script_run_file()

◆ ecs_script_string_interpolate()

◆ ecs_script_update()

◆ ecs_script_vars_declare()

◆ ecs_script_vars_define_id()

◆ ecs_script_vars_fini()

◆ ecs_script_vars_from_iter()

◆ ecs_script_vars_init()

◆ ecs_script_vars_lookup()

◆ ecs_script_vars_pop()

◆ ecs_script_vars_push()

◆ FlecsScriptImport()