sys_transform

Apply changes to position, rotation, and scale to the entities' World transformation matrix, taking into account transforms of parents.

An entity will be processed only if it's marked as dirty by another system:

game.World.Signature[entity] |= Has.Dirty;

sys_transform doesn't depend on the order of entities in the world, but it works best when parents are added before children. This is the default insertion order of instantiate(), but because entities can be later recycled, it's not guaranteed.

sys_transform also updates the transform's Parent field. When reparenting entities, it's not necessary to assign the new parent manually. OTOH, the Parent field should only be referenced after sys_transform has already run during the frame.

import {mat4_compose, mat4_get_translation, mat4_invert, mat4_multiply} from "../../lib/mat4.js"; import {Vec3} from "../../lib/math.js"; import {Entity} from "../../lib/world.js"; import {Transform} from "../components/com_transform.js"; import {Game} from "../game.js"; import {Has, World} from "../world.js";

export function sys_transform(game: Game, delta: number) { for (let ent = 0; ent < game.World.Signature.length; ent++) { if ((game.World.Signature[ent] & QUERY) === QUERY) { let transform = game.World.Transform[ent]; update_transform(game.World, ent, transform); } } }