Flecs v4.1.6

Highlights

• New Data Oriented Hierarchies blog!
• Lots of code hardening with 130 bugfixes and more than 500 new test cases
• New entity range API that correctly handles recycling
• New script features:

// NEW: include statements
include assets.flecs

// NEW: functions
fn color(x: i32, z: i32) -> Rgba {
    {x, 0, z, 1.0}
}

for x in 0..10 {
    for z in 0..10 {
        "e_{x}_{z}" {
            // NEW: assign expressions to components directly
            Rgb: color(x, z).rgb // NEW: swizzle operators
        }
    }
}

• Multiple inspector panels in the explorer:

• New entities can now be created from the explorer:

• New dialog for adding components:

Release notes

This version includes the following improvements:

• [core] Add optimized function for moving small component values across tables
• [core] Improve performance of reparenting for non-fragmenting hierarchies
• [core] Throw error when changing children of already instantiated prefab
• [core] Create default range for already created entities when calling ecs_entity_range_new()
• [core] Throw INVALID_OPERATION assert when parenting to not-alive parent
• [core] Allow for overriding component hooks to support hot reloading
• [core] Reduce the size of ecs_ref_t
• [core] Introduce new update() API for modifying existing systems/observers
• [core] Do not assert when entities have non-unique names
• [core] Always run exclusive access checks when feature is enabled
• [core] Implement new range API that correctly handles recycling
• [core] Allow for specifying offset for ecs_delete_empty_tables() function
• [core] Improve error message when using ecs_field for sparse component
• [cpp] Replace usage of NULL with nullptr in C++ API headers
• [cpp] Replace deprecated std::is_trivial
• [cpp] Implement query group iterator for C++ API
• [cpp] Add support for query::has() methods in C++ API
• [cpp] Add auto-reflection (ECS_STRUCT) support to C++
• [cpp] Make builder::build const (#2033) (thanks @Cobryis!)
• [queries] Allocate iterator vars and written arrays in a single block
• [queries] Skip allocations for fully cached queries
• [queries] Throw error when != is mixed with with || in query expressions
• [queries] Throw error when change detection is enabled on queries with sorting
• [queries] Skip down-traversal leaf check for non-traversable tables
• [queries] Resolve top-level up target without the traversal cache map
• [queries] Improve up traversal performance by reusing down cache buffer
• [queries] Improve performance of iterator creation
• [queries] Refactor query cache to store column indices directly
• [queries] Make group_by unordered by default
• [queries] Make EcsPredMatch query terms case insensitive
• [observers] Add names to singleton constraint observers (thanks @suleymanlaarabi!)
• [observers] Add fast trivial query check for multi-term observers
• [observers] Don't eat observer table locking overhead in release mode
• [pipelines] Remove unused iters and iter_count members from pipeline state
• [pipelines] Prevent setting time scale on stage/readonly world
• [script] Add support for swizzle member expressions
• [script] Allow for direct assigning of expressions to components
• [script] Add support for UUID annotation to flecs script
• [script] Implement script functions
• [script] Add support for include statements to flecs script
• [json] Serialize DontFragment components to JSON
• [json] Refactor type_info serialization to always be a top-level JSON field
• [json] Add support for deserializing array element expressions
• [rest] Add REST parameters for world endpoint
• [os api] Add fopen/fclose hooks to OS API
• [ci] Fix new VS2026 warnings
• [ci] Fix -Wzero-as-null-pointer-constant warnings in C++ headers
• [docs] Add link to Data Oriented Hierarchies blog
• [docs] Fix incorrect doc comment for ecs_new_w_id()
• [docs] Add Appulse to README
• [docs] Extend documentation of CanToggle trait
• [docs] Improve source code comments

This version includes the following bugfixes:

• [core] Fix missing OnAdd event for dont-fragment component on prefab instantiation
• [core] Fix issue where prefab already in use assert would trigger during world cleanup
• [core] Fix issue in hashmap iterator
• [core] Get prefab child name at spawn time instead of caching it
• [core] Fix off-by-one in prefab instance child bounds check
• [core] Map toggle bitset columns without assuming contiguous ids
• [core] Skip non-entity ids when enabling/disabling a prefab
• [core] Return NULL when getting an inherited tag through IsA
• [core] Batch deferred delete commands so adds after delete are not applied
• [core] Refetch component pointer after on_replace hook in batched command flush
• [core] Fix sparse storage not zeroing memory on remove when size param is 0
• [core] Fix ecs_value_move_ctor invoking move instead of move_ctor
• [core] Fix ecs_add_path_w_sep adding ChildOf self pair when path is null
• [core] Fix integer overflow in strbuf float serializer for values >= 2^63
• [core] Don't destroy source toggle bitset when moving single entity that removes a toggle
• [core] Clear toggle bitset bits when clearing table entities without deallocating
• [core] Apply ChildOf side effects when replacing exclusive pair in table graph
• [core] Fix childof base index when prefab child has auto override pair sorting before ChildOf
• [core] Fix ecs_clone using wrong type info when cloning pair components from named entity
• [core] Don't force empty ChildOf reparent diff for non-fragmenting pair tables
• [core] Don't delete prefab tables and dangling pairs during delete_with/remove_all
• [core] Update prefab-children flag on ChildOf record when parent promoted to prefab
• [core] Gate ChildOf unparent cleanup on diff flags to avoid spurious depth recompute
• [core] Skip already-deleted ordered children during fini depth propagation
• [core] Propagate ordered-children tracking flag to pre-existing child tables
• [core] Cleanup prefab tree spawners at fini before deleting entities
• [core] Fix stale EcsIdMarkedForDelete flag on non-fragmenting ChildOf after delete_with
• [core] Fix issue with stale entity in traversal cache when using non-fragmenting hierarchies
• [core] Fix issue where observer invoked during non-fragmenting ChildOf cleanup can see not-alive children
• [core] Fix issue with generating deterministic entity ids for prefab children
• [core] Fix issue where delete_with(*, parent) leaves non-fragmenting children orphaned
• [core] Prevent DontFragment components from being added to table types
• [core] Fix issue with deferred setting of DontFragment component
• [core] Fix issue with deferred cloning of a deleted entity
• [core] Fix issue with removing sparse overridden component while deferred
• [core] Fix issue where ctor is not called correctly when using With trait and emplace()
• [core] Fix issue where Parent component was not assigned before invoking observers
• [core] Fix issue where Parent.value was not always assigned when on_replace hook is called
• [core] Fix issue where alignment macro could cause ASAN false positives
• [core] Fix issue where hooks provided access to uninitialized components
• [core] Fix issues with value pairs that have a 0 target
• [cpp] Fix unreachable code warning for MSVC
• [queries] Fix issue where component wildcard term doesn't match DontFragment component for entities without fragmenting components
• [queries] Fix issue where component wildcard term doesn't match DontFragment components
• [queries] Rebuild sorted table slices when shared order_by component changes
• [queries] Fix crash when equality predicate with wildcard is in OR chain
• [queries] Don't decrement cacheable term count for non-cacheable scope terms
• [queries] Skip (ChildOf, 0) when matching ChildOf with wildcard target
• [queries] Match all rows of non-fragmenting child tables in written sparse up
• [queries] Reset cache iteration cursor when cache op is re-entered
• [queries] Truncate wildcard match vector when rematch yields fewer matches
• [queries] Fix optional up termination bound for ranges with offset
• [queries] Detect multi-level up matches for sparse and non-fragmenting components
• [queries] Continue scanning sibling targets when building up cache
• [queries] Clamp slice to the source range when predicate matching
• [queries] Use field index instead of term index for toggle instruction masks
• [queries] Use field index of order_by term when checking change detection during sort
• [queries] Widen query tokens_len to 32 bits to support expressions longer than 16kb
• [queries] Fix crash when constrained pair target variable has no component record
• [queries] Fix 32-bit shift overflow when constraining iterator variable with id >= 31
• [queries] Use field index instead of term index for sparse row_fields bitmask
• [queries] Map iterator set_fields to cache fields when checking change detection for partially cached queries
• [queries] Sync wildcard match monitors when skipping empty tables during iteration
• [queries] Fix neq predicate slice clamping and stale redo state for written sources
• [queries] Fix issue where cached query for parent hierarchy could go out of sync after a shrink()
• [queries] Fix change detection for fixed-source writes with tag before component
• [queries] Fix issue with dynamic component queries for Any source
• [queries] Fix assert when cascade source loses component with change detection
• [queries] Fix query cache issue with up traversal and recycled entities
• [queries] Fix issue with calling ecs_field_w_size on OR field
• [queries] Fix issue with sparse wildcard pair term with not operator if pair was not yet created
• [observers] Fix issue where observer for variable component is not always invoked
• [observers] Fix issue where observers with non-this sources can return invalid references during world fini
• [observers] Fix issue with yield_existing OnRemove observers where component is deleted before observer
• [observers] Advance component record when forwarding multiple IsA pairs with dirty reachable cache
• [observers] Don't forward Parent component as ChildOf pair twice when wildcard event observer exists
• [observers] Invalidate reachable-id cache when target deleted via non-fragmenting cleanup
• [observers] Fix duplicate OnSet for sparse overrides during prefab instantiation
• [observers] Fix issue where filter terms would not correctly forward table events
• [observers] Fix stale trs/sizes during observer event forwarding
• [observers] Fix issue where code read relationship from id without making sure id is a pair (2)
• [observers] Fix observer up-traversal matching non-pair ids with colliding generation
• [observers] Fix issue where event deduping wasn't working correctly for observer propagation
• [observers] Fix issue where observers would lock the wrong table
• [observers] Fix issues with variables in triggered term of observer
• [commands] Fix removal of dont-fragment component on entity deleted by batched command flush
• [commands] Fix spurious unparent when add/remove of ChildOf is batched on dont-fragment entity
• [commands] Don't transfer parent table records twice for batched remove+add
• [commands] Don't drop batched ensure on non-fragmenting components
• [pipelines] Fix issue where .write() on singleton component doesn't trigger sync point
• [meta] Accept NaN and Inf when deserializing floating point values
• [meta] Parse unsigned 64-bit values without signed overflow in set_string
• [meta] Compare all elements of array members in RTT cmp/equals hooks
• [meta] Serialize uintptr values as full 64-bit unsigned
• [meta] Read enum underlying type in ecs_meta_set_value
• [meta] Fix ecs_meta_get_char returning boolean instead of char value
• [meta] Free all serializer value contexts when serializing table to JSON
• [meta] Add bounds check to flecs_parse_digit to reject too-long number literals
• [meta] Reject single-character string literals in ecs_meta_set_string_literal
• [meta] Fix rtt vector equals returning true for vectors of different length
• [json] Limit control character escaping to component value strings
• [json] Handle invalid escape sequences when parsing JSON strings
• [json] Escape control characters in serialized JSON strings
• [json] Sign-extend signed enum values when serializing to JSON
• [json] Fix issue with deserializing DontFragment components from JSON
• [json] Fix issue where sparse tags aren't serialized to JSON
• [json] Fix issues with escaping characters in JSON
• [http] Fix idle HTTP connection purge and the stale-fd race (thanks @pogeyoji!)
• [script] Fix issue where 'using' wasn't taken into account inside of script function bodies
• [script] Fix template preprocessing of new expression in const
• [script] Fix issues with reporting line numbers for script errors
• [script] Fix issue with partial updates and expression folding
• [script] Fix default child component resolution in nested scopes
• [script] Return error instead of aborting on float equality comparison
• [script] Fail script evaluation when annotation cannot be applied
• [script] Add bounds check to expression element access
• [script] Fix component assignment with match expression
• [script] Fix template preprocessing of component pairs and entity names with vars
• [script] Extend iterator field name array to support up to 32 fields
• [script] Skip stale deferred template instantiation events
• [script] Allow newlines in scripts between with expressions and with scope
• [script] Fix issue where statements after if-else block would not be evaluated
• [script] Ensure that script eval errors are always logged to the console
• [script] Fix issue with deserializing vectors from script
• [parser] Fix buffer overflow from double-parse in flecs_term_parse
• [parser] Fix out of bounds read when string ends with backslash
• [parser] Size token buffer to input in flecs_id_parse to prevent overflow
• [parser] Fix null pointer deref when parsing id with too many pair args
• [parser] Fix query parser bugs
• [modules] Fix issue with loading module from dynamic library
• [log] Fix issue with calling ecs_log_start_capture() twice without ecs_log_stop_capture()

Breaking changes

• [core] New entity ranges API that replaces the ecs_set_entity_range() API
• [queries] Query groups are no longer iterated in order by default
• [build] Changes to how the flecs source code amalgamation works

New Contributors

• @Cobryis made their first contribution in #2033
• @pogeyoji made their first contribution in #2104
• @suleymanlaarabi made their first contribution in #2120

Full Changelog: v4.1.5...v4.1.6