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This diary counts so much steps to reach a good experience of car driving with Leadwerks 4.6, that it just felt so often like unreachable. So as we know the car is built with 8 joints, 4 hinge joints for the tires + 4 slider joints for the dampers I just thought last week about implementing a new little trick like using a spring joint more to connect the visible car to the invisible body of the car. Set the mass to about 300 (usually to heavy for joints) and set the Gravity to false just for this car part... And that's what I obtain: It allows speed until 150-200 km/h, correct behavior by drift, springs, collisions, no trembling. So I'm fine with this, Have fun, thx for watching

View this video Description Just press Space bar to go up in the air.. Smooth landing feature is scripted. TEMP 2022-03-25 10-12-45.mp4

> This is defintely the best result I obtained with Leadwerks physics to build a car; I think this car is good enough so that it could be used in a game. > The car reacts depending on terrain, feeling different if climbing or driving down. The car allows speed driving until 140-160 kmh > The dampers became an upgrade that give me the possibility to construct car over 200 kg. That means simply that the cars drive now with much more stability and give for the player heavier feeling. > It approachs the feeling you get in games klike GTA 4.. Even if the car doesn't really get out of control like sometime it happens ingame when cars are drifting. > Car balancing and transmission could get more fine tuning, but this should be no problem. Here is the demo:

This little game is here free to play: https://1drv.ms/u/s!AiVBgjDAyIXLs1khcglU6UKFbI_4?e=4oK8Sj 1] First step: Adapting the Spline tool to build what we need: I combined some of the possibilities that offers the Spline Tool (great thing) to obtain all this in one: - Cars align and follow the roads (rotation) - While using Physics, and so collisions - While using reverse travel (cars go back on the road) 2] next step: - We need speed cars in this game, beautiful , well smoothed, and challenging that can drive a few rounds on a loop racing road, here it is: I'm just thinking there is no way to overtake this car ! So we have here a nice challenging game. Next step will be build a playable race car, maybe able to overtake this. 3] Playable speed car this video shows a little playable demo challenging 3 cars, here I only get the second place: Last step should be adding Speed infos, Time needed, best time, the place.. 4) Here I managed a player interface to get informations like the speed and the place at which you are actually driving. A little bit car optimization, and here is a little funny challenging game. Next step should be adding options like choose your car model and colors, sounds, music, how much players...

Finishing this today, I'm happy to publish this: https://steamcommunity.com/sharedfiles/filedetails/?id=1662222417 The car is funny to drive, the prefabs is ready-to-use but feel free to change the script variables to test it. Drop the prefabs in the map, it uses the classical FPSPlayer from Leadwerks. The car is based on joints: 4 wheels, 4 damper and 2 Hinges for the directions. The script incorporates smoothing damping modifications to get the car stable; modifications on the velocity. There is a funny speed boost system added. Here is a little video test: Have fun

Now, I wrote a single script that creates suspension, steer and traction You have to create the chassis, 4 wheels, set this script to each one of the wheels and then paly with the configurable parameters. Enjoy: --[[ Autor Juan Ignacio Odriozola (charrua) Purpose: A script that facilitates the making of a simple car all you need is a chassis and 4 wheels assing this scrip to each wheel and set the object chassis then adjust some of the configurable parameters Parent: chassis entity : wheel 3 joints and 2 auxiliary entities are created the chain is: Parent Slider Pivot Hinge Pivot Hinge chassis -suspensionJoint- suspensionPivot -steerJoint- steerPivot -wheelJoint- wheel suspension uses pin 010 (Y axis) steer uses pin 010 (Y axis) wheel pin (must be set depends of wheel orientation) up/down keys are defaults for forward and backward left/right keys are defaults for steer left/right space key is default for brakes steer velocity and start/end angle must be set suspension lenght must be set wheel friction must be set steerAngle set both limits to +/- steerAngle/2 if no key (left/right) is pressed then, target angle is 0 : straight suspensionLenght set both limits to +/- suspensionLength/2 and target distance is set to 0 suspension strength defaults to 1000 which is too much strenght for a light weight car (20 of mass) and not to much for a 200 car of mass each joint is created with a mass of 1, which should be taking into accoung (so for a 4 wheels car, you have a mass of 8 on the 8 joints). there are so many other parameters that may be adjusted: Spring, Strength, Stiffness ... not too much documented :) ]]-- Script.currspeed = 0 Script.chassis = nil--Entity "chassis" Script.pin = Vec3(0,0,1) --Vec3 "wheel Pin" Script.motorspeed=500--float "max motor speed" Script.velcontrolled=false--bool "velControl" Script.suspensionLength=0.2--float "suspension" Script.steerAngle=90--float "steer angle" Script.steerSpeed=100--float "steer velocity" Script.friction=1--float "wheel friction" Script.steerPivot=nil Script.suspensionPivot=nil Script.steerJoint=nil Script.suspensionJoint=nil Script.wheelJoint=nil function Script:Start() local pos = self.entity:GetPosition(false) --true for global if self.chassis ~= nil then self.suspensionPivot = Pivot:Create() self.suspensionPivot:SetPosition(pos) self.suspensionPivot:SetMass(1) self.suspensionPivot:SetCollisionType(Collision.None) self.steerPivot = Pivot:Create() self.steerPivot:SetPosition(pos) self.steerPivot:SetMass(1) self.steerPivot:SetCollisionType(Collision.None) --joints creation self.suspensionJoint = Joint:Slider(pos.x, pos.y, pos.z, 0, 1, 0, self.chassis, self.suspensionPivot) self.steerJoint = Joint:Hinge(pos.x, pos.y, pos.z, 0, -1, 0, self.suspensionPivot, self.steerPivot) self.wheelJoint = Joint:Hinge(pos.x, pos.y, pos.z, self.pin.x, self.pin.y, self.pin.z, self.steerPivot, self.entity) --suspension self.suspensionJoint:EnableLimits() self.suspensionJoint:SetLimits(-self.suspensionLength/2,self.suspensionLength/2) --steerAngle=0 means no steer self.suspensionJoint:SetTargetAngle(0) --at the middle self.suspensionJoint:SetMotorSpeed(1) -- 1 m/s self.suspensionJoint:SetStrength(100) --defatul is 1000 self.suspensionJoint:EnableMotor() --steer self.steerJoint:EnableLimits() self.steerJoint:SetLimits(-self.steerAngle/2,self.steerAngle/2) --steerAngle=0 means no steer self.steerJoint:SetMotorSpeed(self.steerSpeed) self.steerJoint:EnableMotor() --wheel self.entity:SetFriction(self.friction, self.friction) else Debug:Error("no chassis assigned") end end function Script:setMotorSpeed(speed) if self.velcontrolled then --System:Print("setMotorSpeed: "..speed) self.currspeed = speed if speed~=0 then self.wheelJoint:EnableMotor() end self.wheelJoint:SetMotorSpeed(self.currspeed) end end function Script:UpdateWorld() if self.motorspeed>0 then self.wheelJoint:SetAngle(self.wheelJoint:GetAngle()+100) else self.wheelJoint:SetAngle(self.wheelJoint:GetAngle()-100) end if App.window:KeyDown(Key.Space) then self:setMotorSpeed(0) end if self.velcontrolled then if App.window:KeyDown(Key.Up) then self.currspeed = self.currspeed + 10 if self.currspeed>self.motorspeed then self.currspeed=self.motorspeed end if self.currspeed == 10 then self.wheelJoint:EnableMotor() end self.wheelJoint:SetMotorSpeed(self.currspeed) end if App.window:KeyDown(Key.Down) then self.currspeed = self.currspeed - 10 if self.currspeed<-self.motorspeed then self.currspeed=-self.motorspeed end self.wheelJoint:SetMotorSpeed(self.currspeed) end end if self.steerAngle>0 then local direction=0 if App.window:KeyDown(Key.Left) then direction=-self.steerAngle/2 end if App.window:KeyDown(Key.Right) then direction=self.steerAngle/2 end self.steerJoint:SetAngle(direction) else self.steerJoint:SetAngle(0) end end In the other maps i was using a box as a floor to which I set the desired friction, testing this new script i use a terrain and have to figure it out how to set the friction to the terrain... Did some searches and ended with: local n for n=0,self.world:CountEntities()-1 do local entity = self.world:GetEntity(n) if entity:GetClassName()=="Terrain" then terrain = entity System:Print("terrain found!") terrain:SetFriction(10,10) break end end insert this in the app.lua (after load map) and then you can play with terrain friction, the video shows how the car behaves with the defaul terrain friction and then whit a friction of 10,10 Always learning something new A word about some parameters: If you are using a hinge, when you specity speed (SetMotorSpeed) the number means degrees per second. So if you use 3600 as max speed you get 10 revoluions per second. If your tire has, 64cm then d*pi aprox 2 meters per revolution, 10 revolutions per secon aprox 20 meters per second... and if you are lucky 72Km/h If you are using a slider, then speed is un meters per second. Other parameter which is very important is the hinge/slider "pin" which is a vector that tells the direction of movement of the slider or over which plane de hinges open/close For a common door, we need to use the Y axis, so the pin is 0,1,0 I use this pin for the suspension and for the steer but for this script, you must tell the traction pin, which sould be 1,0,0 or 0,0,1 depending on the orientation of your tires If your tires are not facing X nor Z axis, then you have to do some math to get the proper x,z component of the pin In the script I use a Strenght of 100, instead of the 1000 which is default, my car is light weight : 5 + 4*3 = 17 of Mass chassis has 5, each wheel has 1 and the 2 auxiliary pivots has 1 each one whith a friction of 10 on each tire and with a friction of 10 on the terrain looks ok for me (better than I spected at first). Juan

Here there is a way of making a simple car based on hinges This is not a tutorial, is just simply a stating point for the ones that want/like to play arround physics and hinges... I included the entire project and the distribution executable to test the scripts so, you have as I say a starting point and just that, hpe it helps someone This is the editor view and the initial placement of the parts needed Basically I made 3 scripts physicsProperties.lua wheel.lua steer.lua First you have to create and place the car body or chassis, 4 wheels and 6 auxiliary pivots/ or any brush you like (a cube is fine) for the hinges 4 of the auxiliary entities are for the wheels hinges and 2 for the wheels steer. Place the wheel hinge and steer centered with the wheel. After that you may set some script parameters: Wheel scritp: Basically, the position of the entity script holder is used to create a hinge between the "parent" and the "child" you choose (in the picture above: between the auxiliary entity SteerFL and the WheelFL) If vel control is checked then, a motor is enabled for that hinge and keys Up/Down are used to increase/decrease speed If vel control is not cheched, no motor is enabled and the wheel is free to run Be carefull whit the Hinge Pin, which dictates the axis over which the wheel will rotate, in this case I used X axis, but if you use other pieces direction/alignement you should adjust this values. Steer script: The steer hinge is used to turn the wheel to handle car heading, so the pin is the Y axis Limits and Motor are needed to control the steer Limits is for how much the steer will turn right/left using the default keys left/right arrow When you press left or ritght key, the right limit will be set as the hinge angle and the hinge will try to reach this angle at the "steer speed", the same, but whit the left limit happen if you press the left key. physicsProperties just let you adjust the friction of the wheels and or the floor Script.sfrict=0--float "static friction" Script.kfrict=0--float "kinetic friction" function Script:Start() System:Print("phy properties start") self.entity:SetFriction(self.sfrict, self.kfrict) end so simple, and in the editor it looks: Here is a hand drawing of how scripts, objects, parent/child are connected Here is the wheel script Script.currspeed = 0 Script.parent = nil--Entity "Parent" Script.child = nil--Entity "Child" Script.pin = Vec3(0,0,1) --Vec3 "Hinge Pin" Script.motorspeed=500--float "Motor speed" Script.velcontrolled=false--bool "velControl" function Script:Start() System:Print("wheel start") self.entity:Hide() local pos = self.entity:GetPosition(false) --true for global if self.child ~= nil then if self.parent ~= nil then self.joint = Joint:Hinge(pos.x, pos.y, pos.z, self.pin.x, self.pin.y, self.pin.z, self.child, self.parent) else Debug:Error("no parent assigned") end else Debug:Error("no child assigned") end end function Script:setMotorSpeed(speed) if self.velcontrolled then System:Print("setMotorSpeed: "..speed) self.currspeed = speed if speed~=0 then self.joint:EnableMotor() end self.joint:SetMotorSpeed(self.currspeed) end end function Script:UpdateWorld() if self.motorspeed>0 then self.joint:SetAngle(self.joint:GetAngle()+100) else self.joint:SetAngle(self.joint:GetAngle()-100) end if App.window:KeyDown(Key.Space) then self:setMotorSpeed(0) end if self.velcontrolled then if App.window:KeyDown(Key.Up) then self.currspeed = self.currspeed + 10 if self.currspeed>self.motorspeed then self.currspeed=self.motorspeed end if self.currspeed == 10 then self.joint:EnableMotor() end self.joint:SetMotorSpeed(self.currspeed) end if App.window:KeyDown(Key.Down) then self.currspeed = self.currspeed - 10 if self.currspeed<-self.motorspeed then self.currspeed=-self.motorspeed end self.joint:SetMotorSpeed(self.currspeed) end end end Here is the steer scritp Script.parent = nil--Entity "Parent" Script.child = nil--Entity "Child" Script.pin = Vec3(0,1,0) --Vec3 "Hinge Pin" Script.useLimits=false--bool "use limits" Script.limits = Vec2(-45,45) --Vec2 "Limits" Script.useMotor=flase--bool "use motor" Script.motorspeed=50--float "Steer speed" function Script:Start() System:Print("steer start") if self.child == nil then Debug:Error("No child assigned.") end if self.parent == nil then Debug:Error("No parent assigned.") end self.entity:Hide() local pos = self.entity:GetPosition() self.joint = Joint:Hinge(pos.x, pos.y, pos.z, self.pin.x, self.pin.y, self.pin.z, self.child, self.parent) if self.useLimits then self.joint:EnableLimits() self.joint:SetLimits(self.limits.x,self.limits.y) end if self.useMotor then self.joint:SetMotorSpeed(self.motorspeed) self.joint:EnableMotor() end end function Script:UpdateWorld() local direction=0 if App.window:KeyDown(Key.Left) then direction=self.limits.x end if App.window:KeyDown(Key.Right) then direction=self.limits.y end self.joint:SetAngle(direction) end here the distro: simpleCarDistro.zip here the project: simpleCar.zip and here a video... enjoy Juan

I have been getting into some frustration with the car script: This is a video of what happens when I make everything right. I have installed the prefab car and made everything just like in the car, tire 0,1,,2,3 at the right positions and name, physics are all the same . When I make the physics shape a box, the tires just disappear and nothing happens :I In the Video the physics shape is a polyhedron, I havent even started the engine and that happens. Also I have tryed all other physics shape but none worked. rover_mesh.fbx

My lua project was fine and I left it for a few weeks. Now when I load it up the vehicle's forward/reverse controls are reversed. Couldn't figure it out so I created a new project with just flat terrain and shadmar's prefab car. Reversed controls.. Anyone else experiencing this or did I mess something up?