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SimpleTankTracks.html
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<!DOCTYPE html>
<html>
<!--
https://playground.babylonjs.com/#NLLNMD#6
-->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Babylon.js sample code</title>
<!-- Babylon.js -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.6.2/dat.gui.min.js"></script>
<script src="https://assets.babylonjs.com/generated/Assets.js"></script>
<script src="https://preview.babylonjs.com/ammo.js"></script>
<script src="https://preview.babylonjs.com/cannon.js"></script>
<script src="https://preview.babylonjs.com/Oimo.js"></script>
<script src="https://preview.babylonjs.com/earcut.min.js"></script>
<script src="https://preview.babylonjs.com/babylon.js"></script>
<script src="https://preview.babylonjs.com/materialsLibrary/babylonjs.materials.min.js"></script>
<script src="https://preview.babylonjs.com/proceduralTexturesLibrary/babylonjs.proceduralTextures.min.js"></script>
<script src="https://preview.babylonjs.com/postProcessesLibrary/babylonjs.postProcess.min.js"></script>
<script src="https://preview.babylonjs.com/loaders/babylonjs.loaders.js"></script>
<script src="https://preview.babylonjs.com/serializers/babylonjs.serializers.min.js"></script>
<script src="https://preview.babylonjs.com/gui/babylon.gui.min.js"></script>
<script src="https://preview.babylonjs.com/inspector/babylon.inspector.bundle.js"></script>
<style>
html, body {
overflow: hidden;
width: 100%;
height: 100%;
margin: 0;
padding: 0;
}
#renderCanvas {
width: 100%;
height: 100%;
touch-action: none;
}
</style>
</head>
<body>
<canvas id="renderCanvas"></canvas>
<script>
var canvas = document.getElementById("renderCanvas");
var startRenderLoop = function (engine, canvas) {
engine.runRenderLoop(function () {
if (sceneToRender && sceneToRender.activeCamera) {
sceneToRender.render();
}
});
}
var engine = null;
var scene = null;
var sceneToRender = null;
var chassisMesh = null;
var gunMesh = null;
var turretMesh = null;
var lookMesh = null;
var chainMeshes = [];
var redMaterial, blueMaterial;
//tank related variables
var wheelDirection;
var wheelAxle;
var chassisWidth = 2;
var chassisHeight = 1;
var chassisLength = 4;
var centerOfMass;
var massVehicle = 1000;
var chassisWidth, chassisHeight, chassisLength;
var ZERO_QUATERNION = new BABYLON.Quaternion();
var wheelAxisFront = 0.9;
var wheelHalfTrack = 1.6;
var wheelAxisHeight = 0.5;
var wheelRadius = 0.4;
var wheelWidth = 0.3;
var friction = 5;
var suspensionStiffness = 5; //keeps the chassis intact with the chains
var suspensionDamping = 0.5;
var suspensionCompression = 0.5;
var suspensionRestLength = 0.8;
var rollInfluence = 0.0;
var steeringIncrement = .02;
var steeringClamp = 0.4;
var maxEngineForce = 500;
var maxBreakingForce = 10;
var incEngine = 10.0;
var engineForce = 0;
var vehicleSteering = 0;
var rotationMultiplier = 4;//this factor is multiplied to make the chain wheels move faster to rotate faster
var turretAngle=0;
var gunAngle = 0;
var breakingForce = 0;
var chainCollisionMargin=0.15; //added to make the chain visible during collision with the bumps
var wheelMeshesLeft = new Array(9);
var wheelMeshesRight = new Array(9);
var bones = null;
var vehicleReady = false;
var drawDebugHelpers = false;
var actions = {accelerate:false,brake:false,right:false,left:false};
var keysActions = {
"KeyW":'acceleration',
"KeyS":'braking',
"KeyA":'left',
"KeyD":'right',
"KeyZ":'turret_left',
"KeyC":'turret_right',
"KeyQ":'gun_up',
"KeyE":'gun_down'
};
var createDefaultEngine = function() { return new BABYLON.Engine(canvas, true, { preserveDrawingBuffer: true, stencil: true, disableWebGL2Support: false}); };
//This demo is based on this excellent open source project: https://github.com/RuanLucasGD/Simple-Militay-Tank-Physics
//The tank rig is also from the same repo. so a huge shout out to RuanLucasGD
var createScene = async function () {
// This creates a basic Babylon Scene object (non-mesh)
var scene = new BABYLON.Scene(engine);
//gltf is right handed so we ask babylon.js to set righthandedness for us
scene.useRightHandedSystem = true;
var camera = new BABYLON.ArcRotateCamera("camera", BABYLON.Tools.ToRadians(-90), BABYLON.Tools.ToRadians(65), 20, BABYLON.Vector3.Zero(), scene);
// This attaches the camera to the canvas
camera.attachControl(canvas, true);
// This creates a light, aiming 0,1,0 - to the sky (non-mesh)
var light = new BABYLON.DirectionalLight("sun", new BABYLON.Vector3(-1, -1, -1), scene);
light.position = new BABYLON.Vector3(0,-10,20);
light.intensity = 1.25;
//light.autoCalcShadowZBounds = true;
//light.autoUpdateExtends = true;
//we create some materials for our obstacles
redMaterial = new BABYLON.StandardMaterial("RedMaterial");
redMaterial.diffuseColor = new BABYLON.Color3(0.8,0.4,0.5);
redMaterial.emissiveColor = new BABYLON.Color3(0.8,0.4,0.5);
blueMaterial = new BABYLON.StandardMaterial("BlueMaterial");
blueMaterial.diffuseColor = new BABYLON.Color3(0.5,0.4,0.8);
blueMaterial.emissiveColor = new BABYLON.Color3(0.5,0.4,0.8);
// This creates a light, aiming 0,1,0 - to the sky (non-mesh)
var ambient = new BABYLON.HemisphericLight("ambient1", new BABYLON.Vector3(0, 1, 0), scene);
ambient.intensity = 0.125;
// Enable physics
await Ammo();
scene.enablePhysics(new BABYLON.Vector3(0,-10,0), new BABYLON.AmmoJSPlugin());
// Our built-in 'ground' shape.
var ground = BABYLON.MeshBuilder.CreateGround("ground", {width: 460, height: 460, depth: 2}, scene);
let groundMaterial = new BABYLON.StandardMaterial("Ground Material", scene);
ground.material = groundMaterial;
ground.receiveShadows = true;
//make shadow generator
var shadowGenerator = new BABYLON.ShadowGenerator(1024, light);
shadowGenerator.useBlurExponentialShadowMap = true;
shadowGenerator.setDarkness(0.5);
//Next, we create our bumps to show good tank movement
//create some cylinders and make physics impostor from them
const bump = BABYLON.MeshBuilder.CreateCylinder("bump", {height:20});
//cylinder is oriented in XZ plane, we want our bump to be oriented in XY plane
bump.rotate(BABYLON.Axis.Z, Math.PI/2);
bump.position.set(0, -0.3, 10);
//create physics impostor so our tank can collide with this bump
bump.physicsImpostor = new BABYLON.PhysicsImpostor( bump,
BABYLON.PhysicsImpostor.CylinderImpostor, { mass: 0 }, scene
);
//create 4 copies
for(var i=1; i<=4; ++i)
{
var b2 = bump.createInstance("bump"+i);
b2.position.set(0, -0.3, 10+ 3*i);
b2.physicsImpostor = new BABYLON.PhysicsImpostor( b2, BABYLON.PhysicsImpostor.CylinderImpostor, { mass: 0 }, scene);
}
//create 4 more bumps but slightly bigger than previosus 4
for(var i=1; i<=4; ++i)
{
var b2 = bump.createInstance("bump"+i);
b2.scaling.z = 2;
b2.position.set(0, -0.3, 22 + 3*i);
b2.physicsImpostor = new BABYLON.PhysicsImpostor( b2, BABYLON.PhysicsImpostor.CylinderImpostor, { mass: 0 }, scene);
}
//tank vehicle initialization
//this is the direction of motion of tank wheels
wheelDirection = new Ammo.btVector3(0, -1, 0);
//this is the direction of tank wheel axle
wheelAxle = new Ammo.btVector3(-1, 0, 0);
//set the center of mass of tank. This value controls the overall feel of tank forces
centerOfMass = new Ammo.btVector3(0, 0.25, 0);
//attach key event handlers
window.addEventListener( 'keydown', keydown);
window.addEventListener( 'keyup', keyup);
BABYLON.SceneLoader.ImportMesh("", "./models/", "Tank3.glb", scene, function (meshes, particleSystems, skeletons)
{
//we store our bones for easier access later
bones = skeletons[0].bones;
//we traverse each mesh
meshes.forEach((mesh) =>
{
//we add it to the shadow caster so shadows are casted by this mesh
shadowGenerator.addShadowCaster(mesh);
if(mesh.name == "main body")
{
chassisMesh = mesh; //we store reference to the chassis mesh
camera.lockedTarget = mesh; //we also lock the camera on the mesh
//mesh.isVisible = false;
}
//for turret, main body and look, we color them green
if(mesh.name == "turret" || mesh.name == "main body" || mesh.name == "look")
{
mesh.material = new BABYLON.StandardMaterial("tank_material");
mesh.material.diffuseColor = new BABYLON.Color3(152/255.0, 204/255.0, 119/255.0);
//mesh.isVisible = false;
//we store reference to each sub-mesh for reference later
if( mesh.name == "turret")
turretMesh = mesh;
if( mesh.name == "look")
lookMesh = mesh;
}
//this is the left and right chains
if(mesh.name == "mat left" || mesh.name == "mats right")
{
//we assign them chain material
mesh.material = new BABYLON.StandardMaterial("chain_material");
mesh.material.diffuseTexture = new BABYLON.Texture("./textures/mat_texture.png", scene);
//mesh.isVisible = false;
//we store our chain meshes for use later
chainMeshes.push( mesh );
//had to add this in because for some unknown reason the chain meshes disappear at some odd camera angles.
//this line disables view fraustum culling for the chain meshes
mesh.alwaysSelectAsActiveMesh = true;
}
//for the gun, exit cover and antenna we color them dark black
if(mesh.name == "gun" || mesh.name == "exit" || mesh.name == "antenna")
{
mesh.material = new BABYLON.StandardMaterial("gun_material");
mesh.material.diffuseColor = new BABYLON.Color3(41/255.0, 41/255.0, 41/255.0);
//mesh.isVisible = false;
//we store reference to the gun mesh
if(mesh.name == "gun")
gunMesh = mesh;
}
//the meshes wl and wr are our tank wheels, we assign them black material
if(mesh.name.startsWith("wl") || mesh.name.startsWith("wr"))
{
mesh.material = new BABYLON.StandardMaterial("wheel_material");
mesh.material.diffuseColor = new BABYLON.Color3(70/255.0, 70/255.0, 70/255.0);
//the other wheels are instances so we assign each instance to its appropriate array
if(mesh.instances != undefined)
{
mesh.instances.forEach((inst) => {
//we add this instance to the shadow caster
shadowGenerator.addShadowCaster(inst);
var index = parseInt(inst.name[2]);
//based on the name we but the instance in its appropriate array
if(inst.name.startsWith("wl") && inst.name.length == 3)
wheelMeshesLeft[index-1] = inst;
else
wheelMeshesRight[index-1] = inst;
});
}
//if the wheel mesh is stored as a mesh, we store it into its appropriate array
if(mesh.name.startsWith("wl") && mesh.name.length == 3)
{
var index = parseInt(mesh.name[2]);
//console.log(index);
wheelMeshesLeft[index-1] = mesh;
}
if(mesh.name.startsWith("wr") && mesh.name.length == 3)
{
var index = parseInt(mesh.name[2]);
//console.log(index);
wheelMeshesRight[index-1] = mesh;
}
}
});
//create our tank vehicle
createTankVehicle(scene, new BABYLON.Vector3(0, 4, -20), ZERO_QUATERNION);
//create tank tracks using trailmesh
var trailLeft = new BABYLON.TrailMesh('left track', wheelMeshesLeft[7], scene, .5, 60, true);
var trailRight = new BABYLON.TrailMesh('right track', wheelMeshesRight[7], scene, .5, 60, true);
var sourceMat = new BABYLON.StandardMaterial('sourceMat', scene);
sourceMat.emissiveColor = sourceMat.diffuseColor = new BABYLON.Color3(0.01, 0.01, 0.01);
sourceMat.specularColor = new BABYLON.Color3.Black();
// sourceMat.diffuseTexture = new BABYLON.Texture("https://raw.githubusercontent.com/mmmovania/BabylonPhysicsTutorials/master/textures/mat_texture.png", scene);
trailLeft.position.y = -wheelRadius;
trailRight.position.y = -wheelRadius;
trailLeft.material = sourceMat;
trailRight.material = sourceMat;
//create tank tracks using ribbon
//Array of paths to construct ribbon
/*const trailLength = 5;
const yOffset = -wheelRadius - 0.1;
const myPaths = [
[ new BABYLON.Vector3(-wheelRadius, yOffset, 0),
new BABYLON.Vector3(-wheelRadius, yOffset, -trailLength),
],
[ new BABYLON.Vector3(0, yOffset, 0),
new BABYLON.Vector3(0, yOffset, -trailLength),
],
[ new BABYLON.Vector3(wheelRadius, yOffset, 0),
new BABYLON.Vector3(wheelRadius, yOffset, -trailLength),
]
];
//Create ribbon with updatable parameter set to true for later changes
let ribbon = BABYLON.MeshBuilder.CreateRibbon("left track", {pathArray: myPaths, updatable: true, sideOrientation: BABYLON.Mesh.DOUBLESIDE});
for(var i=0;i<3;++i)
{
myPaths[i][0].y = -myPaths[i][0].y;
myPaths[i][1].y = -myPaths[i][1].y;
}
let ribbon2 = BABYLON.MeshBuilder.CreateRibbon("right track", {pathArray: myPaths, updatable: true, sideOrientation: BABYLON.Mesh.DOUBLESIDE});
var sourceMat = new BABYLON.StandardMaterial('sourceMat', scene);
sourceMat.emissiveColor = sourceMat.diffuseColor = new BABYLON.Color3(0, 0, 0);
sourceMat.specularColor = new BABYLON.Color3.Black();
// sourceMat.diffuseTexture = new BABYLON.Texture("https://raw.githubusercontent.com/mmmovania/BabylonPhysicsTutorials/master/textures/mat_texture.png", scene);
ribbon.material = sourceMat;
ribbon.rotation.z = Math.PI/2.0;
ribbon.parent = bones[18].getTransformNode();
ribbon2.rotation.y = Math.PI/2.0;
ribbon2.rotation.z = Math.PI/2.0;
ribbon2.material = sourceMat;
ribbon2.parent = bones[24].getTransformNode();
*/
});
//create physics objects from the ground mesh
ground.physicsImpostor = new BABYLON.PhysicsImpostor(ground,
BABYLON.PhysicsImpostor.BoxImpostor, { mass: 0, friction: 0.5, restitution: 0.5 }, scene
);
//register prerender callback to initiate vehicle motion
scene.registerBeforeRender(function(){
//time step delta (dt)
var dt = engine.getDeltaTime().toFixed()/1000;
//is the vehicle setup finished?
if(vehicleReady)
{
//get the tanks current speed from ammo.js
var speed = vehicle.getCurrentSpeedKmHour();
var maxSteerVal = 0.2;
breakingForce = 0;
engineForce = 0;
//calculate the turret angle based on the user input
if(actions.turret_left)
{
turretAngle += 10*dt;
}
if(actions.turret_right)
{
turretAngle -= 10*dt;
}
//calculate the gun angle based on the user input
var gunRotated = false;
var deltaX = 0;
if(actions.gun_up)
{
deltaX = 10*dt;
gunRotated = true;
}
if(actions.gun_down)
{
deltaX = -10*dt;
gunRotated = true;
}
//apply gun rotation based on the given input and clamp to the range
if(gunRotated)
{
gunAngle += deltaX;
if(gunAngle > -40 && gunAngle < 3)
gunMesh.rotate(BABYLON.Axis.X, BABYLON.Tools.ToRadians(deltaX));
gunAngle = Math.max(-40, Math.min(gunAngle, 3));
}
//see if we are accelerating
if(actions.acceleration){
//are we decreasing or increasing
if (speed < -1){
breakingForce = maxBreakingForce;
}else {
engineForce = maxEngineForce;
}
} else if(actions.braking){
//are we decreasing or increasing to signify we want to go reverse
if (speed > 1){
breakingForce = maxBreakingForce;
}else {
engineForce = -maxEngineForce ;
}
}
//are we turning right
if(actions.right)
{
if (vehicleSteering < steeringClamp){
vehicleSteering += steeringIncrement;
}
}
//are we turning left
else if(actions.left)
{
if (vehicleSteering > -steeringClamp){
vehicleSteering -= steeringIncrement;
}
} else {
vehicleSteering *= 0.1 ; //this dampens the return of the wheel when the user releases the key
}
//if we are rotating the tank right, we apply +ve force on the left wheels and -ve force on the right wheels
//this results in the left chain moving forward and the right chain moving backwards
if(actions.right)
{
//apply +ve force on the left side wheels
for(var i=0; i<9;++i)
{
vehicle.applyEngineForce(maxEngineForce*rotationMultiplier, i);
}
//apply -ve force on the right side wheels
for(var i=9; i<18;++i)
{
vehicle.applyEngineForce(-maxEngineForce*rotationMultiplier, i);
}
}
//for left rotation we do vice verse, i.e. we apply +ve force on the right wheels and -ve force on the left wheels
//this results in the right chain moving forward and the left chain moving backwards
else if(actions.left)
{
//apply -ve force on the left side wheels
for(var i=0; i<9;++i)
{
vehicle.applyEngineForce(-maxEngineForce*rotationMultiplier, i);
}
//apply +ve force on the right side wheels
for(var i=9; i<18;++i)
{
vehicle.applyEngineForce(maxEngineForce*rotationMultiplier, i);
}
}
//else we are moving either forward or backward, we apply same force to all wheels
else
{
for(var i=0; i<9;++i)
{
vehicle.applyEngineForce(engineForce, i);
}
for(var i=9; i<18;++i)
{
vehicle.applyEngineForce(engineForce, i);
}
}
//apply break on the vehicle with unequal amount of force for front and rear wheels
for(var i=0; i<18;++i)
vehicle.setBrake(breakingForce, i);
//aanimate the two chain textures using texture vOffset
if(actions.left || actions.right) {
//when rotating left or right we use the vehiclesteering factor to modify the speed of motion
chainMeshes[0].material.diffuseTexture.vOffset -= vehicleSteering*10*dt;
chainMeshes[1].material.diffuseTexture.vOffset += vehicleSteering*10*dt;
}
else
{
//otherwise we use the speed of tank for making the texture animate
chainMeshes.forEach( (chain) => {
chain.material.diffuseTexture.vOffset += (speed*dt);
});
}
//once we have applied all forces to ammo.js vehicle, we need to update the
//position and orientation of our tank chassis and wheel.
var tm, p, q, i;
var n = 9;
//get the updated position and orientation of each left side wheel
for (i = 0; i < n; i++)
{
vehicle.updateWheelTransform(i, true);
tm = vehicle.getWheelTransformWS(i);
p = tm.getOrigin();
q = tm.getRotation();
//update the left wheels
if(wheelMeshesLeft[i])
{
//update the wheel positions and rotations
wheelMeshesLeft[i].showBoundingBox = drawDebugHelpers;
wheelMeshesLeft[i].position.set(p.x(), p.y()+chainCollisionMargin, p.z());
wheelMeshesLeft[i].rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
//the wheel is oriented wrongly so we fix it by a z rotation of 90 degrees
wheelMeshesLeft[i].rotate(BABYLON.Axis.Z, Math.PI/2);
//we update the corresponding bone for each wheel
//left side wheel bones are stored from indices 4, 6, 8, 10, ...
bones[4+i*2].getTransformNode().setAbsolutePosition(p.x(), p.y()+chainCollisionMargin, p.z());
bones[4+i*2].getTransformNode().computeWorldMatrix(true);
}
//ammo.js does not calculate rotation if a wheel is not on the ground so we copy the rotation quat from the adjacent neighbor
if(i==(n-1))
{
var q1 = wheelMeshesLeft[1].rotationQuaternion;
var qn = wheelMeshesLeft[i-1].rotationQuaternion;
wheelMeshesLeft[0].rotationQuaternion.set(q1.x, q1.y, q1.z, q1.w);
wheelMeshesLeft[i].rotationQuaternion.set(qn.x, qn.y, qn.z, qn.w);
}
}
//get the updated position and orientation of each right side wheel
for (i = 0; i < n; i++)
{
//we add 9 becuase 0-8 are left side wheels
vehicle.updateWheelTransform(i+9, true);
tm = vehicle.getWheelTransformWS(i+9);
p = tm.getOrigin();
q = tm.getRotation();
//update the right size wheels
if(wheelMeshesRight[i])
{
//update the wheel positions and rotations
wheelMeshesRight[i].showBoundingBox = drawDebugHelpers;
wheelMeshesRight[i].position.set(p.x(), p.y()+chainCollisionMargin, p.z());
wheelMeshesRight[i].rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
//the wheel is oriented wrongly so we fix it by a z rotation of 90 degrees
wheelMeshesRight[i].rotate(BABYLON.Axis.Z, Math.PI/2);
//we update the corresponding bone for each wheel
//right side wheel bones are stored in bones array from indices 38, 36, 34, 32, 30, ...
bones[38-2*i].getTransformNode().setAbsolutePosition(p.x(), p.y()+chainCollisionMargin, p.z());
bones[38-2*i].getTransformNode().computeWorldMatrix();
}
//ammo.js does not calculate rotation if a wheel is not on the ground so we copy the rotation quat from the adjacent neighbor
if(i==(n-1))
{
var q1 = wheelMeshesRight[1].rotationQuaternion;
var qn = wheelMeshesRight[i-1].rotationQuaternion;
wheelMeshesRight[0].rotationQuaternion.set(q1.x, q1.y, q1.z, q1.w);
wheelMeshesRight[i].rotationQuaternion.set(qn.x, qn.y, qn.z, qn.w);
}
}
//get the updated position and orientation of our car chassis
tm = vehicle.getChassisWorldTransform();
p = tm.getOrigin();
q = tm.getRotation();
if(chassisMesh != null) {
//update the position and orientation of the root bone so that the whole skeleton follows the moving tank
bones[0].getTransformNode().setAbsolutePosition(p.x(), p.y(), p.z());
bones[0].getTransformNode().rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
bones[0].getTransformNode().computeWorldMatrix();
//update the chassis mesh position and orientation
chassisMesh.position.set(p.x(), p.y(), p.z());
chassisMesh.rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
//update the turret mesh position and orientation
turretMesh.position.set(p.x(), p.y(), p.z());
turretMesh.rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
turretMesh.rotate(BABYLON.Axis.Y, BABYLON.Tools.ToRadians(turretAngle));
//update the periscope mesh position and orientation
lookMesh.position.set(p.x(), p.y(), p.z());
lookMesh.rotationQuaternion.set(q.x(), q.y(), q.z(), q.w());
//update the light position on the tanks position
light.position = chassisMesh.position;
}
}
});
return scene;
}
//This function creates our tank ammo.js vehicle
function createTankVehicle(scene, pos, quat)
{
//Going Native
var physicsWorld = scene.getPhysicsEngine().getPhysicsPlugin().world;
//create the ammo.js vehicle geometry to match our chassis size
var geometry = new Ammo.btBoxShape(new Ammo.btVector3(chassisWidth * .5, chassisHeight * .5, chassisLength * .5));
//create the transform for the vehicle
var transform = new Ammo.btTransform();
transform.setIdentity();
transform.setOrigin(new Ammo.btVector3(0,1,0));
transform.setRotation(new Ammo.btQuaternion(quat.x, quat.y, quat.z, quat.w));
var motionState = new Ammo.btDefaultMotionState(transform);
//create the local inertia of the vehicle based on its mass
var localInertia = new Ammo.btVector3(0, 0, 0);
geometry.calculateLocalInertia(massVehicle, localInertia);
//
var transform2 = new Ammo.btTransform();
transform2.setIdentity();
transform2.setOrigin(centerOfMass);
//create the rigidbody to match our tank chassis
var compound = new Ammo.btCompoundShape();
compound.addChildShape( transform2, geometry );
var body = new Ammo.btRigidBody(new Ammo.btRigidBodyConstructionInfo(massVehicle, motionState, compound, localInertia));
body.setActivationState(4);
//add our rigidbody to the physics world
physicsWorld.addRigidBody(body);
//setup a raycaster to control the car placement
var tuning = new Ammo.btVehicleTuning();
var rayCaster = new Ammo.btDefaultVehicleRaycaster(physicsWorld);
vehicle = new Ammo.btRaycastVehicle(tuning, body, rayCaster);
vehicle.setCoordinateSystem(0, 1, 2);
//add vehicle to the physics world
physicsWorld.addAction(vehicle);
//get the chassis world transform
var trans = vehicle.getChassisWorldTransform();
//creates one wheel with physics properties
function addWheel(isFront, pos, radius)
{
var wheelInfo = vehicle.addWheel(
pos,
wheelDirection,
wheelAxle,
suspensionRestLength,
radius,
tuning,
isFront);
wheelInfo.set_m_suspensionStiffness(suspensionStiffness);
wheelInfo.set_m_wheelsDampingRelaxation(suspensionDamping);
wheelInfo.set_m_wheelsDampingCompression(suspensionCompression);
wheelInfo.set_m_maxSuspensionForce(1000);
wheelInfo.set_m_frictionSlip(40);
wheelInfo.set_m_rollInfluence(rollInfluence);
}
//add the left side wheels
for(var i=3;i>=-5;--i)
{
var z = wheelAxisFront + i + ((i==3)?0.3:0);
addWheel(false, new Ammo.btVector3(wheelHalfTrack, (i==3 || i==-5)?wheelAxisHeight+0.6:wheelAxisHeight, z), wheelRadius);
}
//add the right side wheels
for(var i=3;i>=-5;--i)
{
var z = wheelAxisFront + i + ((i==3)?0.3:0);
addWheel(false, new Ammo.btVector3(-wheelHalfTrack, (i==3 || i==-5)?wheelAxisHeight+0.6:wheelAxisHeight, z), wheelRadius);
}
vehicleReady = true;
}
//key up event handler
function keyup(e) {
if(keysActions[e.code]) {
actions[keysActions[e.code]] = false;
}
}
//key down event handler
function keydown(e) {
if(keysActions[e.code]) {
actions[keysActions[e.code]] = true;
}
}
window.initFunction = async function() {
var asyncEngineCreation = async function() {
try {
return createDefaultEngine();
} catch(e) {
console.log("the available createEngine function failed. Creating the default engine instead");
return createDefaultEngine();
}
}
window.engine = await asyncEngineCreation();
if (!engine) throw 'engine should not be null.';
startRenderLoop(engine, canvas);
window.scene = createScene();};
initFunction().then(() => {scene.then(returnedScene => { sceneToRender = returnedScene; });
});
// Resize
window.addEventListener("resize", function () {
engine.resize();
});
</script>
</body>
</html>