Initial commit

example.project.json

@@ -0,0 +1,71 @@
+{
+    "name": "example",
+    "tree": {
+        "$className": "DataModel",
+        "ReplicatedStorage": {
+            "Shared": {
+                "$path": "example/src/shared"
+            },
+            "ecs": {
+                "$path": "src"
+            }
+        },
+        "ServerScriptService": {
+            "Server": {
+                "$path": "example/src/server"
+            }
+        },
+        "StarterPlayer": {
+            "StarterPlayerScripts": {
+                "Client": {
+                    "$path": "example/src/client"
+                }
+            }
+        },
+        "Workspace": {
+            "$properties": {
+                "FilteringEnabled": true
+            },
+            "Baseplate": {
+                "$className": "Part",
+                "$properties": {
+                    "Anchored": true,
+                    "Color": [
+                        0.38823,
+                        0.37254,
+                        0.38823
+                    ],
+                    "Locked": true,
+                    "Position": [
+                        0,
+                        -10,
+                        0
+                    ],
+                    "Size": [
+                        512,
+                        20,
+                        512
+                    ]
+                }
+            }
+        },
+        "Lighting": {
+            "$properties": {
+                "Ambient": [
+                    0,
+                    0,
+                    0
+                ],
+                "Brightness": 2,
+                "GlobalShadows": true,
+                "Outlines": false,
+                "Technology": "Voxel"
+            }
+        },
+        "SoundService": {
+            "$properties": {
+                "RespectFilteringEnabled": true
+            }
+        }
+    }
+}

example/.gitignore

@@ -0,0 +1,6 @@
+# Project place file
+/example.rbxlx
+
+# Roblox Studio lock files
+/*.rbxlx.lock
+/*.rbxl.lock

example/README.md

@@ -0,0 +1,17 @@
+# example
+Generated by [Rojo](https://github.com/rojo-rbx/rojo) 7.4.1.
+
+## Getting Started
+To build the place from scratch, use:
+
+```bash
+rojo build -o "example.rbxlx"
+```
+
+Next, open `example.rbxlx` in Roblox Studio and start the Rojo server:
+
+```bash
+rojo serve
+```
+
+For more help, check out [the Rojo documentation](https://rojo.space/docs).

example/src/client/init.client.luau

@@ -0,0 +1 @@
+print("Hello world, from client!")

example/src/server/init.server.luau

@@ -0,0 +1 @@
+print("Hello world, from server!")

example/src/shared/common.luau

@@ -0,0 +1,277 @@
+--!optimize 2
+--!native
+
+local jecs = require(game:GetService("ReplicatedStorage").ecs)
+
+type World = jecs.WorldShim
+type Entity<T = any> = jecs.Entity<T>
+
+local function LOOP_ERROR(str)
+    -- We don't want to interrupt the loop when we error
+    task.spawn(error, str)
+end
+
+local Scheduler: (World, ...ModuleScript) -> (number) -> ()
+do
+    local systems
+    local N
+    local w
+    local dt
+    local systemsNames
+
+    local function run(system)
+        local name = systemsNames[system]
+
+        return function()
+            debug.profilebegin(name)
+            debug.setmemorycategory(name)
+            system(w, dt)
+            debug.profileend()
+        end
+    end
+
+    local function loop(sinceLastFrame)
+        debug.profilebegin("loop()")
+
+        for i = N, 1, -1 do
+            local system = systems[i]
+
+            dt = sinceLastFrame
+
+            local didNotYield, why = xpcall(function()
+                for _ in run(system) do end
+            end, debug.traceback)
+
+            if didNotYield then
+				continue
+			end
+
+			if string.find(why, "thread is not yieldable") then
+				N -= 1
+				table.remove(systems, i)
+				LOOP_ERROR("Not allowed to yield in the systems."
+    				.. "\n"
+    				.. "System: "
+    				.. debug.info(system, "n")
+    				.. " has been ejected"
+				)
+				continue
+			end
+			LOOP_ERROR(why)
+        end
+
+        debug.profileend()
+        debug.resetmemorycategory()
+    end
+
+    function Scheduler(world, ...)
+        systems = { ... }
+        systemsNames = {}
+        N = #systems
+        w = world
+
+        for i, system in systems do
+            systems[i] = require(system)
+            systemsNames[system] = debug.info(system, "n")
+        end
+
+        return loop
+    end
+end
+
+type Tracker<T> = { track: (world: World, fn: (changes: {
+        added: () -> () -> (number, T),
+        removed: () -> () -> number,
+        changed: () -> () -> (number, T, T)
+    }) -> ()) -> ()
+}
+local ChangeTracker: <T>(world: any, component: Entity<T>) -> Tracker<T>
+
+do
+    local world: World
+    local T
+    local PreviousT
+    local addedComponents
+    local removedComponents
+    local isTrivial
+    local added
+    local removed
+
+    local function changes_added()
+        added = true
+        local q = world:query(T):without(PreviousT)
+        return function()
+            local id, data = q:next()
+            if not id then
+                return nil
+            end
+
+            if isTrivial == nil then
+                isTrivial = typeof(data) ~= "table"
+            end
+
+            if not isTrivial then
+                data = table.clone(data)
+            end
+
+            addedComponents[id] = data
+            return id, data
+        end
+    end
+
+    local function shallowEq(a, b)
+        for k, v in a do
+            if b[k] ~= v then
+                return false
+            end
+        end
+        return true
+    end
+
+    local function changes_changed()
+        local q = world:query(T, PreviousT)
+
+        return function()
+            local id, new, old = q:next()
+            while true do
+                if not id then
+                    return nil
+                end
+
+                if not isTrivial then
+                    if not shallowEq(new, old) then
+                        break
+                    end
+                elseif new ~= old then
+                    break
+                end
+
+                id, new, old = q:next()
+            end
+
+            addedComponents[id] = new
+
+            return id, old, new
+        end
+    end
+
+    local function changes_removed()
+        removed = true
+
+        local q = world:query(PreviousT):without(T)
+        return function()
+            local id = q:next()
+            if id then
+            table.insert(removedComponents, id)
+            end
+            return id
+        end
+    end
+
+    local changes = {
+        added = changes_added,
+        changed = changes_changed,
+        removed = changes_removed,
+    }
+
+    local function track(fn)
+        added = true
+        removed = true
+
+        fn(changes)
+
+        if not added then
+            for _ in changes_added() do
+            end
+        end
+
+        if not removed then
+            for _ in changes_removed() do
+            end
+        end
+
+        for e, data in addedComponents do
+            world:set(e, PreviousT, if isTrivial then data else table.clone(data))
+        end
+
+        for _, e in removedComponents do
+            world:remove(e, PreviousT)
+        end
+    end
+
+    local tracker = { track = track }
+
+    function ChangeTracker<T>(worldToTrack: World, component: Entity<T>): Tracker<T>
+        world = worldToTrack
+        T = component
+        -- We just use jecs.Rest because people will probably not use it anyways
+        PreviousT = jecs.pair(jecs.Rest, T)
+        addedComponents = {}
+        removedComponents = {}
+
+        return tracker
+    end
+end
+
+local Allocator: <T>(World, Entity<T>, (T) -> ()) -> { alloc: (Entity) -> (), free: (Entity) -> (), deinit: () -> () }
+
+do
+    local arena: {}
+    local world
+    local cleanup
+    local id
+
+    local function alloc(entity: Entity)
+        table.insert(arena, entity)
+    end
+
+    local function deinit()
+        for _, e in arena do
+            cleanup(world:get(e, id), e)
+            world:clear(e)
+        end
+    end
+
+    local function free(entity: Entity)
+        local e = table.remove(arena, table.find(arena, entity))
+        if e then
+            cleanup(world:get(e, id), e)
+            world:clear(e)
+        end
+    end
+
+    local handle = {
+        alloc = alloc,
+        deinit = deinit,
+        free = free,
+    }
+
+    setmetatable(handle, handle)
+
+    function Allocator<T>(w: World, T: Entity<T>, fn: (T) -> ())
+        arena = {}
+        world = w
+        cleanup = fn
+        id = T
+
+        return handle
+    end
+end
+
+local world = jecs.World.new()
+local Model = world:component() :: Entity<Model>
+
+local ModelAllocator = Allocator(world,
+    Model, function(model) model:Destroy() end)
+
+local e = world:entity()
+world:set(e, Model, Instance.new("Model"))
+
+ModelAllocator.alloc(e)
+ModelAllocator.free(e)
+
+return {
+    Scheduler = Scheduler,
+    ChangeTracker = ChangeTracker,
+    Allocator = Allocator
+}

src/init.luau

@@ -1207,7 +1207,7 @@ return {
 	Component = EcsComponent,
 	Wildcard = EcsWildcard :: Entity,
 	w = EcsWildcard :: Entity,
-	Rest = EcsRest,
+	Rest = EcsRest :: Entity,
 
 	pair = (ECS_PAIR :: any) :: <R, T>(pred: Entity, obj: Entity) -> number,
 

test/tests.luau

@@ -594,10 +594,10 @@ do
             end
 
             if is_trivial == nil then
-                isTrivial = typeof(data) ~= "table"
+                is_trivial = typeof(data) ~= "table"
             end
 
-            if not isTrivial then
+            if not is_trivial then
                 data = table.clone(data)
             end
 
@@ -635,7 +635,7 @@ do
                     return nil
                 end
 
-                if isTrivial and new ~= old then
+                if is_trivial and new ~= old then
                 elseif diff(new, old) then
                     break
                 end
@@ -685,7 +685,7 @@ do
         end
 
         for e, data in add do
-            world:set(e, PreviousT, if isTrivial then data else table.clone(data))
+            world:set(e, PreviousT, if is_trivial then data else table.clone(data))
         end
     end