Addition of a trailer attachment and detachment system

README.md

@@ -78,6 +78,11 @@ A pack of content and entity classes to add cars, motorcycles, planes, helicopte
 | `glide_global_damage_multiplier` `<number>` | Multiplier for damage taken from any source (except from collisions)
 | `glide_player_collision_damage_multiplier` `<number>` | Damage multiplier for players inside vehicles taking damage from hard collisions.
 
+### Trailer
+| Command | Description
+| ------- | -----------
+| `glide_trailer_attach_percentage_wheel` `<number>` | Percentage of wheels required on trailer to attach it to a vehicle. Default : 0.6
+
 ### Sandbox limits
 
 | Command | Description

lua/autorun/sh_glide.lua

@@ -183,6 +183,9 @@ if SERVER then
     CreateConVar( "glide_world_physics_damage_multiplier", "1", FCVAR_ARCHIVE + FCVAR_NOTIFY, "Damage multiplier taken by Glide vehicles after colliding against the world.", 0, 10 )
     CreateConVar( "glide_global_damage_multiplier", "1", FCVAR_ARCHIVE + FCVAR_NOTIFY, "Multiplier for damage taken from any source (except collisions).", 0, 10 )
     CreateConVar( "glide_player_collision_damage_multiplier", "0.5", FCVAR_ARCHIVE + FCVAR_NOTIFY, "Damage multiplier for players inside vehicles taking damage from hard collisions.", 0, 2 )
+
+    -- Trailer convars
+    CreateConVar( "glide_trailer_attach_percentage_wheel", "0.6", FCVAR_ARCHIVE + FCVAR_NOTIFY + FCVAR_REPLICATED, "Percentage of wheels required on trailer to attach it to a vehicle.", 0, 1 )
 end
 
 -- Toggles

lua/entities/base_glide/init.lua

@@ -804,3 +804,109 @@ function ENT:GetSpawnColor()
     local color = colors[math.random( #colors )]
     return Color( color.r, color.g, color.b )
 end
+
+function ENT:AttachTrailer( trailer )
+    if not IsValid( trailer ) then return end
+
+    trailer:AttachToVehicle( self )
+    self.AttachedTrailer = trailer
+
+    local driver = self:GetDriver()
+    if not IsValid( driver ) then return end
+
+    Glide.SendNotification( driver, {
+        text = "#glide.notify.vehicle_attach",
+        icon = "materials/glide/icons/trailer.png",
+        sound = "buttons/button15.wav",
+        immediate = true
+    } )
+end
+
+function ENT:DetachTrailer()
+    if not IsValid( self.AttachedTrailer ) then return end
+
+    self.AttachedTrailer:DetachFromVehicle( self )
+    self.AttachedTrailer = nil
+
+    local driver = self:GetDriver()
+    if not IsValid( driver ) then return end
+
+    Glide.SendNotification( driver, {
+        text = "#glide.notify.vehicle_detach",
+        icon = "materials/glide/icons/trailer.png",
+        sound = "buttons/button15.wav",
+        immediate = true
+    } )
+end
+
+local percentageWheel = GetConVar( "glide_trailer_attach_percentage_wheel" ):GetFloat() -- At least 60% of wheels must be on the trailer
+local minWheels = {
+    ["base_glide_heli"]       = 0,
+    ["base_glide_boat"]       = 0,
+    ["base_glide_bike"]       = 2,
+    ["base_glide_motorcycle"] = 2,
+    ["base_glide_plane"]      = 2,
+    ["base_glide_car"]        = 3,
+    ["base_glide_tank"]       = 4,
+}
+
+local OFFSET_WHEEL = Vector( 0, 0, 200 )
+
+local function canFilter( vehicle, ent )
+    return ent:GetClass() ~= "glide_wheel" and ent ~= vehicle
+end
+
+function ENT:ToggleAttachDetachTrailer()
+    if self.cooldownAttachTrailer and CurTime() < self.cooldownAttachTrailer then return end
+    self.cooldownAttachTrailer = CurTime() + 0.5
+
+    if self:GetSpeed() > 5 then return end
+
+    local minWheel = minWheels[self.Base]
+    if not minWheel then return end
+
+    if IsValid( self.AttachedTrailer ) then
+        self:DetachTrailer()
+    else
+        local totalWheels = table.Count( self.wheels ) or 0
+        if minWheel == 0 or totalWheels == 0 then
+            local posVehicle = self:GetPos()
+            local Trace = util.TraceLine( {
+                start = posVehicle,
+                endpos = posVehicle - OFFSET_WHEEL,
+                filter = function( ent ) return canFilter( self, ent ) end
+            } )
+
+            local trailerEntity = Trace.Entity
+            if IsValid( trailerEntity ) and trailerEntity.Base == "base_glide_trailer" then
+                self:AttachTrailer( trailerEntity )
+            end
+        else
+            totalWheels = math.max( totalWheels, minWheel )
+
+            local wheelCount = 0
+            local trailerEntity = nil
+            for _, wheel in Glide.EntityPairs( self.wheels ) do
+                if not IsValid( wheel ) then continue end
+
+                local posWheel = wheel:GetPos()
+                local Trace = util.TraceLine( {
+                    start = posWheel,
+                    endpos = posWheel - OFFSET_WHEEL,
+                    filter = function( ent ) return canFilter( self, ent ) end
+                } )
+
+                local trailer = Trace.Entity
+                if IsValid( trailer ) and trailer.Base == "base_glide_trailer" and ( not IsValid( trailerEntity ) or trailerEntity == trailer ) then
+                    wheelCount = wheelCount + 1
+
+                    trailerEntity = Trace.Entity
+                end
+            end
+
+            if math.ceil( wheelCount / totalWheels ) >= percentageWheel then
+                self:AttachTrailer( trailerEntity )
+            end
+        end
+    end
+end

lua/entities/base_glide/shared.lua

@@ -44,6 +44,7 @@ function ENT:SetupDataTables()
     self:NetworkVar( "Int", "EngineState" )
     self:NetworkVar( "Bool", "IsEngineOnFire" )
     self:NetworkVar( "Bool", "IsLocked" )
+    self:NetworkVar( "Bool", "IsAttachedToTrailer" )
 
     self:NetworkVar( "Int", "LockOnState" )
     self:NetworkVar( "Entity", "LockOnTarget" )

lua/entities/base_glide/sv_input.lua

@@ -174,6 +174,8 @@ function ENT:SetInputBool( seatIndex, action, pressed )
             icon = "materials/glide/icons/" .. ( self.inputThrottleModifierToggle and "play_next" or "fast_forward" ) .. ".png",
             immediate = true
         } )
+    elseif action == "attach_vehicle" then
+        self:ToggleAttachDetachTrailer()
     end
 
     if action == "toggle_engine" then

lua/entities/base_glide_trailer.lua

@@ -105,3 +105,44 @@ function ENT:OnPostThink( _dt, selfTbl )
     self:SetTurnSignalState( attachedVehicle:GetTurnSignalState() )
     self:SetIsVehicleReversing( attachedVehicle:IsReversing() )
 end
+
+function ENT:AttachToVehicle( vehicle )
+    if not IsValid( vehicle ) then return end
+
+    constraint.Weld( self, vehicle, 0, 0, 0, true )
+    constraint.NoCollide( self, vehicle, 0, 0 )
+    self.listAttachedVehicle = self.listAttachedVehicle or {}
+    self.listAttachedVehicle[vehicle] = true
+
+    vehicle:EnableEngine( false )
+    vehicle:SetIsAttachedToTrailer( true )
+    vehicle:CallOnRemove( ( "Glide_TrailerDetach_%s" ):format( self:EntIndex() ), function()
+        if not IsValid( self ) then return end
+        self:DetachFromVehicle( vehicle )
+    end )
+end
+
+function ENT:DetachFromVehicle( vehicle )
+    if not IsValid( vehicle ) then return end
+
+    constraint.RemoveConstraints( vehicle, "Weld" )
+    constraint.RemoveConstraints( vehicle, "NoCollide" )
+
+    if self.listAttachedVehicle then
+        self.listAttachedVehicle[vehicle] = nil
+    end
+
+    vehicle:EnableEngine( true )
+    vehicle:RemoveCallOnRemove( ( "Glide_TrailerDetach_%s" ):format( self:EntIndex() ) )
+    vehicle:SetIsAttachedToTrailer( false )
+end
+
+function ENT:GetAttachedVehicles()
+    return self.listAttachedVehicle or {}
+end
+
+function ENT:OnRemove()
+    for vehicle, _ in pairs( self:GetAttachedVehicles() ) do
+        self:DetachFromVehicle( vehicle )
+    end
+end

lua/entities/glide_wheel/cl_init.lua

@@ -215,7 +215,7 @@ function ENT:Think()
         rollFactor = rollFactor + fastFactor
     end
 
-    if rollFactor > 0.1 and selfTbl.enableParticles then
+    if rollFactor > 0.1 and selfTbl.enableParticles and not parent:GetIsAttachedToTrailer() then
         rollFactor = Clamp( rollFactor, 0, 0.5 )
 
         local eff = EffectData()
@@ -227,7 +227,7 @@ function ENT:Think()
         Effect( "glide_tire_roll", eff )
     end
 
-    if forwardSlipFactor > 0.2 and selfTbl.enableParticles then
+    if forwardSlipFactor > 0.2 and selfTbl.enableParticles and not parent:GetIsAttachedToTrailer() then
         forwardSlipFactor = Clamp( forwardSlipFactor, 0, 1 )
 
         local eff = EffectData()

lua/glide/sh_input.lua

@@ -78,6 +78,7 @@ Glide.AddInputAction( "general_controls", "switch_weapon", KEY_R )
 Glide.AddInputAction( "general_controls", "toggle_engine", KEY_I )
 Glide.AddInputAction( "general_controls", "headlights", KEY_H )
 Glide.AddInputAction( "general_controls", "free_look", KEY_LALT )
+Glide.AddInputAction( "general_controls", "attach_vehicle", KEY_M )
 
 --[[
     Inputs that only apply to land vehicle types

resource/localization/en/glide_vehicles.properties

@@ -101,6 +101,7 @@ glide.input.signal_right=Right turn signal
 glide.input.aircraft_controls=Aircraft controls
 glide.input.countermeasures=Countermeasures
 glide.input.free_look=Free look (Flying with mouse only)
+glide.input.attach_vehicle=Attach/Detach vehicle to trailer
 glide.input.landing_gear=Landing gear
 glide.input.pitch_up=Pitch up
 glide.input.pitch_down=Pitch down
@@ -204,6 +205,8 @@ glide.notify.tip.countermeasures=Press %s to deploy countermeasures.
 glide.notify.tip.trailer_attached=Trailer attached. Press %s to release it.
 glide.notify.tip.trailer_detached=Trailer detached.
 glide.notify.tip.vtol_toggle=Hold %s to toggle the "Vertical Take-Off and Landing" mode.
+glide.notify.vehicle_attach=The vehicle has been attached to the trailer.
+glide.notify.vehicle_detach=The vehicle has been detached from the trailer.
 
 # HUD
 

resource/localization/fr/glide_vehicles.properties

@@ -101,6 +101,7 @@ glide.input.signal_right=Clignotant droit
 glide.input.aircraft_controls=Contrôles des aéronefs
 glide.input.countermeasures=Contre-mesures
 glide.input.free_look=Regard libre (Vol uniquement avec la souris)
+glide.input.attach_vehicle=Attacher/Détacher un véhicule a une remorque
 glide.input.landing_gear=Train d'atterrissage
 glide.input.pitch_up=Monter (Tangage)
 glide.input.pitch_down=Descendre (Tangage)
@@ -205,6 +206,8 @@ glide.notify.tip.countermeasures=Appuyez sur %s pour déployer les contre-mesure
 glide.notify.tip.trailer_attached=Remorque attachée. Appuyez sur %s pour la libérer.
 glide.notify.tip.trailer_detached=Remorque détachée.
 glide.notify.tip.vtol_toggle=Maintenez %s pour basculer le mode « Décollage et atterrissage verticaux ».
+glide.notify.vehicle_attach=Le véhicule a été attaché à la remorque.
+glide.notify.vehicle_detach=Le véhicule a été détaché de la remorque.
 
 # HUD