我想制作一个浏览器VR射击游戏，使用Three.js和Ammo.js进行物理和刚体设计。设置了VR头和控制器，模型已加载，但子弹不会像我想要的那样从枪上射出。当我尝试仅使用Three.js在场景中没有僵尸来做同样的事情时，我使用Three.js文档中的“ vector.applyQuaternion”，并且奏效了，子弹是从枪顶发射的。问题是我找不到与使用ammo.js类似的东西
不使用ammo.js的代码
... function handleController( controller ) {
if ( controller1.userData.isSelecting ) {
bullet1.position.set( controller1.position.x , controller1.position.y + 0.018 , controller1.position.z -0.01);
bullet1.userData.velocity.x = 0;
bullet1.userData.velocity.y = 10;
bullet1.userData.velocity.z = 10;
bullet1.userData.velocity.applyQuaternion( controller1.quaternion );
scene.add(bullet1);
}
if ( controller2.userData.isSelecting ) {
bullet2.position.set( controller2.position.x , controller2.position.y + 0.018 , controller2.position.z -0.01 );
bullet2.userData.velocity.x = 0;
bullet2.userData.velocity.y = 10;
bullet2.userData.velocity.z = 10;
bullet2.userData.velocity.applyQuaternion( controller2.quaternion );
scene.add(bullet2);
}
} ...
function render() {
handleController( controller1 );
handleController( controller2 );
var delta = clock.getDelta()
bullet1.position.x -= bullet1.userData.velocity.x * delta;
bullet1.position.y -= bullet1.userData.velocity.y * delta;
bullet1.position.z -= bullet1.userData.velocity.z * delta;
bullet2.position.x -= bullet2.userData.velocity.x * delta;
bullet2.position.y -= bullet2.userData.velocity.y * delta;
bullet2.position.z -= bullet2.userData.velocity.z * delta;
renderer.render( scene, camera );
}
带有ammo.js的代码
function createBullet1RigidBody( threeObject, physicsShape, mass ) {
//threeObject.position.copy( pos );
//threeObject.quaternion.copy( quat1 );
quat1.set( controller1.position.x, controller1.position.y , controller1.position.z , Math.PI/2 );
pos1 = new THREE.Vector3 ( controller1.position.x, controller1.position.y , controller1.position.z );
var transform = new Ammo.btTransform();
transform.setIdentity();
transform.setOrigin( new Ammo.btVector3( controller1.position.x, controller1.position.y, controller1.position.z -0.5) );
transform.setRotation( new Ammo.btQuaternion( quat1.x, quat1.y, quat1.z, quat1.w ) );
var motionState = new Ammo.btDefaultMotionState( transform );
var localInertia = new Ammo.btVector3( 0, 0, 0 );
physicsShape.calculateLocalInertia( mass, localInertia );
var rbInfo = new Ammo.btRigidBodyConstructionInfo( mass, motionState, physicsShape, localInertia );
var body1 = new Ammo.btRigidBody( rbInfo );
threeObject.userData.physicsBody = body1;
scene.add( threeObject );
if ( mass > 0 ) {
bullet1Bodies.push( threeObject );
// Disable deactivation
body1.setActivationState( 4 );
}
physicsWorld.addRigidBody( body1 );
return body1;
}
function createBullet2RigidBody( threeObject, physicsShape, mass ) {
//threeObject.position.copy( pos );
//threeObject.quaternion.copy( quat2 );
var transform = new Ammo.btTransform();
transform.setIdentity();
transform.setOrigin( new Ammo.btVector3( controller2.position.x, controller2.position.y, controller2.position.z -0.5 ) );
transform.setRotation( new Ammo.btQuaternion( quat.x, quat.y, quat.z, quat.w ) );
var motionState = new Ammo.btDefaultMotionState( transform );
var localInertia = new Ammo.btVector3( 0, 0, 0 );
physicsShape.calculateLocalInertia( mass, localInertia );
var rbInfo = new Ammo.btRigidBodyConstructionInfo( mass, motionState, physicsShape, localInertia );
var body2 = new Ammo.btRigidBody( rbInfo );
threeObject.userData.physicsBody = body2;
scene.add( threeObject );
if ( mass > 0 ) {
bullet2Bodies.push( threeObject );
// Disable deactivation
body2.setActivationState( 4 );
}
physicsWorld.addRigidBody( body2 );
return body2;
}
...
function handleController( controller ) {
if ( controller1.userData.isSelecting ) {
var bullet1Mass = 0.1;
var bullet1Radius = 0.6;
var bullet1 = new THREE.Mesh( geometry_bullet, new THREE.MeshLambertMaterial( { color: 0x2661b9 } ) );
var bullet1Shape = new Ammo.btSphereShape ( bullet1Radius );
bullet1Shape.setMargin ( margin );
var bullet1_body = createBullet1RigidBody( bullet1, bullet1Shape, bullet1Mass, bullet1Radius );
//bullet1.position.set( pos1.x, pos1.y, pos1.z );
bullet1.userData.physicsBody.setFriction( 0 );
bullet1_body.setLinearVelocity( new Ammo.btVector3( 100, 100, 100 , controller1.quaternion) );
}
if ( controller2.userData.isSelecting ) {
var bullet2Mass = 0.1;
var bullet2Radius = 0.6;
var bullet2 = new THREE.Mesh( geometry_bullet, new THREE.MeshLambertMaterial( { color: 0xee2f2f } ) );
var bullet2Shape = new Ammo.btSphereShape ( bullet2Radius );
var pos2 = new THREE.Vector3 ( controller2.position.x, controller2.position.y + 10, controller2.position.z +10 );
bullet2Shape.setMargin ( margin );
//quat2.set( 0,0,0,1 );
var bullet2_body = createBullet2RigidBody( bullet2, bullet2Shape, bullet2Mass, bullet2Radius, pos2, quat2 );
//var pos2 = bullet2.position.set( controller2.position.x, controller2.position.y, controller2.position.z -0.1 );
bullet2.userData.physicsBody.setFriction( 0 );
bullet2_body.setLinearVelocity( new Ammo.btVector3( 0, 0, controller2.position.z *100 ) );
//bullet2.userData.physicsBody.applyQuaternion(controller2.quaternion);
}
}
结果是创建了项目符号，但它们仅在z轴上移动。如果我在x轴上移动控制器，则bullet2的速度会发生变化，而子弹仅在z轴上移动。 bullet1的项目符号跟随x，y，z轴上的运动，但不跟随控制器的旋转。 “ bullet2.userData.physicsBody.applyQuaternion（controller2.quaternion）;”这行是注释，如果我删除这些小节，则会收到此错误“ TypeError：bullet2.userData.physicsBody.applyQuaternion不是函数”。我原本希望在没有弹药（userData.velocity.applyQuaternion）的情况下能做与上一个示例相同的操作，但是ammo.js中没有LinearVelocity，我只能使用getLinearVelocity和setLinearVelocity。
答案 0 :(得分：0)
基于我见过的弹药版本，您对setLinearVelocity（）的调用不正确。 btVector3构造函数必须仅使用x，y，z。使用ThreeJS数学对其进行计算，类似于在其他地方进行的操作（选择幅度并通过控制器的四元数旋转vector3）。也许可以解决您的问题。
注意：我质疑为什么需要对子弹进行物理模拟。大多数射击游戏都不这样做。方便快捷地是在检查是否拦截玩家/墙壁时直观地更新进度。如果需要重力效果，请在每帧上应用小的垂直下落。如果您想弹跳，请使用截距曲面的法线更改速度。弹药引擎非常适合手榴弹弹跳（复杂，不可预测的相互作用）之类的东西。