Input: Refactor +use handling to fix continuous use (#1821)

saibotk · web-flow · commit 2cb83f380bea · 2026-02-08T13:44:43.000+01:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -20,6 +20,12 @@ All notable changes to TTT2 will be documented here. Inspired by [keep a changel
 - Fixed loading screen tips translation (by @mexikoedi)
 - Fixed missing `limit_left` translation (by @mexikoedi)
 - Fixed `GetHeadshotMultiplier` nil value error (by @mexikoedi)
+- Fixed continuous use not working correctly with entities like health stations (by @saibotk)
+
+### Removed / Breaking Changes
+
+- Removed `IsSpecialUsableEntity` & `IsUsableEntity` functions on entities (by @saibotk)
+- Changed `ENT:ClientUse()`: Removed return value, now always blocks the default use handling (by @saibotk)
 
 ## [v0.14.5b](https://github.com/TTT-2/TTT2/tree/v0.14.5b) (2025-08-18)
 
diff --git a/gamemodes/terrortown/entities/entities/ttt_base_placeable.lua b/gamemodes/terrortown/entities/entities/ttt_base_placeable.lua
@@ -14,8 +14,6 @@ ENT.isDestructible = true
 
 ENT.pickupWeaponClass = nil
 
-ENT.CanUseKey = true
-
 local soundDeny = Sound("HL2Player.UseDeny")
 
 ---
@@ -55,29 +53,6 @@ function ENT:PlayerCanPickupWeapon(activator)
     return true
 end
 
-if CLIENT then
-    ---
-    -- Hook that is called if a player uses their use key while focusing on the entity.
-    -- Implement this to predict early if entity can be picked up
-    -- @return bool True to prevent pickup
-    -- @realm client
-    function ENT:ClientUse()
-        local client = LocalPlayer()
-
-        if not IsValid(client) or not client:IsTerror() or not self.pickupWeaponClass then
-            return true
-        end
-
-        if not self:PlayerCanPickupWeapon(client) then
-            LANG.Msg("pickup_fail", nil, MSG_MSTACK_WARN)
-
-            self:EmitSound(soundDeny)
-
-            return true
-        end
-    end
-end -- CLIENT
-
 if SERVER then
     local soundRumble = {
         Sound("physics/concrete/concrete_break2.wav"),
diff --git a/gamemodes/terrortown/entities/entities/ttt_c4/shared.lua b/gamemodes/terrortown/entities/entities/ttt_c4/shared.lua
@@ -721,9 +721,7 @@ else -- CLIENT
     })
 
     ---
-    -- Hook that is called if a player uses their use key while focusing on the entity.
-    -- Shows C4 UI
-    -- @return bool True to prevent pickup
+    -- This is called if a player uses their use key while in proximity of the entity.
     -- @realm client
     function ENT:ClientUse()
         if IsValid(self) then
@@ -733,8 +731,6 @@ else -- CLIENT
                 ShowC4Disarm(self)
             end
         end
-
-        return true
     end
 
     ---
diff --git a/gamemodes/terrortown/entities/entities/ttt_hat_deerstalker.lua b/gamemodes/terrortown/entities/entities/ttt_hat_deerstalker.lua
@@ -11,8 +11,6 @@ ENT.PrintName = "hat_deerstalker_name"
 ENT.Model = Model("models/ttt/deerstalker.mdl")
 ENT.CanHavePrints = false
 
-ENT.CanUseKey = true
-
 ---
 -- @realm shared
 function ENT:SetupDataTables()
diff --git a/gamemodes/terrortown/entities/entities/ttt_health_station.lua b/gamemodes/terrortown/entities/entities/ttt_health_station.lua
@@ -198,19 +198,6 @@ else
         walkkey = Key("+walk", "WALK"),
     }
 
-    ---
-    -- Hook that is called if a player uses their use key while focusing on the entity.
-    -- Early check if client can use the health station
-    -- @return bool True to prevent pickup
-    -- @realm client
-    function ENT:ClientUse()
-        local client = LocalPlayer()
-
-        if not IsValid(client) or not client:IsPlayer() or not client:IsActive() then
-            return true
-        end
-    end
-
     -- handle looking at healthstation
     hook.Add("TTTRenderEntityInfo", "HUDDrawTargetIDHealthStation", function(tData)
         local client = LocalPlayer()
diff --git a/gamemodes/terrortown/gamemode/client/cl_keys.lua b/gamemodes/terrortown/gamemode/client/cl_keys.lua
@@ -26,7 +26,8 @@ function GM:OnSpawnMenuOpen()
 end
 
 ---
--- Runs when a bind has been pressed. Allows to block commands.
+-- Runs when a bind has been pressed. Allows blocking commands.
+-- @note This does not block continuous use activation on the server when running into the entity with +use already being pressed.
 -- @note By using the "alias" console command, this hook can be effectively circumvented
 -- @note To stop the user from using +attack, +left and any other movement commands
 -- of the sort, please look into using @{GM:StartCommand} instead
@@ -64,6 +65,17 @@ function GM:PlayerBindPress(ply, bindName, pressed)
             return true
         end
     elseif bindName == "+use" and pressed then
+        -- Handle special spectator use override
+        if ply:IsSpec() then
+            net.Start("TTT2PlayerUseEntity")
+            net.WriteEntity(nil)
+            net.WriteString("spectator_use")
+            net.SendToServer()
+
+            -- Suppress the +use bind
+            return true
+        end
+
         -- Do old traitor button check
         if TBHUD:PlayerIsFocused() then
             if ply:KeyDown(IN_WALK) then
@@ -76,47 +88,56 @@ function GM:PlayerBindPress(ply, bindName, pressed)
         end
 
         -- Find out if a marker is focused otherwise check normal use
-        local isClientOnly = false
-        local useEnt = markerVision.GetFocusedEntity()
-        local isRemote = IsValid(useEnt)
-        if not isRemote then
-            local shootPos = ply:GetShootPos()
-
-            local tr = util.TraceLine({
-                start = shootPos,
-                endpos = shootPos + ply:GetAimVector() * 100,
-                filter = ply,
-                mask = bit.bor(MASK_SOLID, CONTENTS_DEBRIS),
-            })
-
-            useEnt = tr.Entity
-
-            if not tr.Hit or not IsValid(useEnt) then
-                useEnt = nil
-            end
+        local markerVisionFocusedEnt = markerVision.GetFocusedEntity()
 
-            if useEnt and isfunction(useEnt.ClientUse) then
-                isClientOnly = useEnt:ClientUse()
-            end
-        elseif isfunction(useEnt.RemoteUse) then
+        if IsValid(markerVisionFocusedEnt) and isfunction(markerVisionFocusedEnt.RemoteUse) then
             sound.ConditionalPlay(soundUse, SOUND_TYPE_INTERACT)
 
-            isClientOnly = useEnt:RemoteUse(ply)
+            local clientSideOnly = markerVisionFocusedEnt:RemoteUse()
+
+            if not clientSideOnly then
+                -- Call this on the server too.
+                -- This cannot be done on the server's Entity:Use hook etc., because we suppress the +use bind here to not trigger it
+                -- on other close by entities.
+
+                net.Start("TTT2PlayerUseEntity")
+                net.WriteEntity(markerVisionFocusedEnt)
+                net.WriteString("remote_use")
+                net.SendToServer()
+            end
+
+            -- Suppress the +use bind here, so it does not trigger the Entity:Use hook on other close by entities.
+            -- Suppressing means, that the server will not see this key as being pressed anymore, even if the client is still pressing it.
+            return true
         end
 
-        -- If returned true by ClientUse or RemoteUse, then dont call Use and UseOverride or RemoteUse serverside
-        if isClientOnly then
+        -- This can sometimes deviate from the entity that the server actually uses.
+        -- But this is fine for now.
+        -- See https://github.com/Facepunch/garrysmod-issues/issues/5027
+        local clientUseEnt = ply:GetUseEntity()
+
+        -- Handle client side use methods
+        -- E.g. for showing client side UIs on interaction
+        if IsValid(clientUseEnt) and isfunction(clientUseEnt.ClientUse) then
+            clientUseEnt:ClientUse()
+
             return true
         end
 
-        if IsValid(useEnt) and (ply:IsSpec() or useEnt:IsSpecialUsableEntity()) then
+        -- Handle special weapon pickup use override
+        local trace = util.QuickTrace(ply:GetShootPos(), ply:GetAimVector() * 100, ply)
+
+        if IsValid(trace.Entity) and trace.Entity:IsWeapon() then
             net.Start("TTT2PlayerUseEntity")
-            net.WriteEntity(useEnt)
-            net.WriteBool(isRemote)
+            net.WriteEntity(trace.Entity)
+            net.WriteString("weapon_pickup")
             net.SendToServer()
 
+            -- Suppress the +use bind
             return true
         end
+
+        -- Otherwise the +use is executed as usual, triggering the server-side Entity:Use function.
     elseif string.sub(bindName, 1, 4) == "slot" and pressed then
         local idx = tonumber(string.sub(bindName, 5, -1)) or 1
 
diff --git a/gamemodes/terrortown/gamemode/server/sv_entity.lua b/gamemodes/terrortown/gamemode/server/sv_entity.lua
@@ -2,14 +2,6 @@
 -- @ref https://wiki.facepunch.com/gmod/Entity
 -- @class Entity
 
--- Caps taken from here: https://github.com/ValveSoftware/source-sdk-2013/blob/55ed12f8d1eb6887d348be03aee5573d44177ffb/mp/src/game/shared/baseentity_shared.h#L21-L38
-FCAP_IMPULSE_USE = 16
-FCAP_CONTINUOUS_USE = 32
-FCAP_ONOFF_USE = 64
-FCAP_DIRECTIONAL_USE = 128
-FCAP_USE_ONGROUND = 256
-FCAP_USE_IN_RADIUS = 512
-
 local safeCollisionGroups = {
     [COLLISION_GROUP_WEAPON] = true,
 }
@@ -78,38 +70,6 @@ function entmeta:Spawn()
     oldSpawn(self)
 end
 
----
--- Checks if the entity has any use functionality attached. This can be attached in the engine/via hammer or by
--- setting `.CanUseKey` to true. Player ragdolls and weapons always have use functionality attached.
--- @param[default=0] number requiredCaps Use caps that are required for this entity
--- @return boolean Returns true if the entity is usable by the player
--- @ref https://github.com/ValveSoftware/source-sdk-2013/blob/0d8dceea4310fde5706b3ce1c70609d72a38efdf/sp/src/game/server/player.cpp#L2766C71-L2781
--- @realm server
-function entmeta:IsUsableEntity(requiredCaps)
-    requiredCaps = requiredCaps or 0
-
-    -- special case: TTT specific lua based use interactions
-    -- when we're looking for specifically the lua use
-    if self:IsSpecialUsableEntity() then
-        return true
-    end
-
-    local caps = self:ObjectCaps()
-
-    if
-        bit.band(
-                caps,
-                bit.bor(FCAP_IMPULSE_USE, FCAP_CONTINUOUS_USE, FCAP_ONOFF_USE, FCAP_DIRECTIONAL_USE)
-            )
-            > 0
-        and bit.band(caps, requiredCaps) == requiredCaps
-    then
-        return true
-    end
-
-    return false
-end
-
 ---
 -- Some sounds are important enough that they shouldn't be affected by CPASAttenuationFilter
 -- @param string snd The name of the sound to be played
diff --git a/gamemodes/terrortown/gamemode/server/sv_player.lua b/gamemodes/terrortown/gamemode/server/sv_player.lua
diff --git a/gamemodes/terrortown/gamemode/shared/sh_entity.lua b/gamemodes/terrortown/gamemode/shared/sh_entity.lua
