physics-manager.ts

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import { IPhysicsWorld, IRaycastOptions } from '../spec/i-physics-world';
import { createPhysicsWorld } from './instance';
import { PhysicsMaterial } from './assets/physics-material';
import { PhysicsRayResult } from './physics-ray-result';

const { property, ccclass } = cc._decorator;

/**
 * !#en
 * Physical systems manager.
 * !#zh
 * 物理系统管理器。
 * @class Physics3DManager
 */
@ccclass("cc.Physics3DManager")
export class Physics3DManager {

    /**
     * !#en
     * Whether to enable the physics system, default is false.
     * !#zh
     * 是否启用物理系统，默认不启用。
     * @property {boolean} enabled
     */
    get enabled (): boolean {
        return this._enabled;
    }
    set enabled (value: boolean) {
        this._enabled = value;
    }

    /**
     * !#en
     * Whether to allow the physics system to automatically hibernate, default is true.
     * !#zh
     * 物理系统是否允许自动休眠，默认为 true。
     * @property {boolean} allowSleep
     */
    get allowSleep (): boolean {
        return this._allowSleep;
    }
    set allowSleep (v: boolean) {
        this._allowSleep = v;
        if (!CC_EDITOR && !CC_PHYSICS_BUILTIN) {
            this.physicsWorld.allowSleep = this._allowSleep;
        }
    }

    /**
     * !#en
     * The maximum number of sub-steps a full step is permitted to be broken into, default is 2.
     * !#zh
     * 物理每帧模拟的最大子步数，默认为 2。
     * @property {number} maxSubStep
     */
    get maxSubStep (): number {
        return this._maxSubStep;
    }
    set maxSubStep (value: number) {
        this._maxSubStep = value;
    }

    /**
     * !#en
     * Time spent in each simulation of physics, default is 1/60s.
     * !#zh
     * 物理每步模拟消耗的固定时间，默认为 1/60 秒。
     * @property {number} deltaTime
     */
    get deltaTime (): number {
        return this._fixedTime;
    }
    set deltaTime (value: number) {
        this._fixedTime = value;
    }

    /**
     * !#en
     * Whether to use a fixed time step.
     * !#zh
     * 是否使用固定的时间步长。
     * @property {boolean} useFixedTime
     */
    get useFixedTime (): boolean {
        return this._useFixedTime;
    }
    set useFixedTime (value: boolean) {
        this._useFixedTime = value;
    }

    /**
     * !#en
     * Gravity value of the physics simulation, default is (0, -10, 0).
     * !#zh
     * 物理世界的重力数值，默认为 (0, -10, 0)。
     * @property {Vec3} gravity
     */
    get gravity (): cc.Vec3 {
        return this._gravity;
    }
    set gravity (gravity: cc.Vec3) {
        this._gravity.set(gravity);
        if (!CC_EDITOR && !CC_PHYSICS_BUILTIN) {
            this.physicsWorld.gravity = gravity;
        }
    }

    /**
     * !#en
     * Gets the global default physical material. Note that builtin is null.
     * !#zh
     * 获取全局的默认物理材质，注意：builtin 时为 null。
     * @property {PhysicsMaterial | null} defaultMaterial
     * @readonly
     */
    get defaultMaterial (): PhysicsMaterial | null {
        return this._material;
    }

    readonly physicsWorld: IPhysicsWorld;
    readonly raycastClosestResult = new PhysicsRayResult();
    readonly raycastResults: PhysicsRayResult[] = [];

    @property
    private _enabled = false;

    @property
    private _allowSleep = true;

    @property
    private readonly _gravity = new cc.Vec3(0, -10, 0);

    @property
    private _maxSubStep = 1;

    @property
    private _fixedTime = 1.0 / 60.0;

    @property
    private _useFixedTime = true;

    useAccumulator = false;
    private _accumulator = 0;

    useFixedDigit = false;
    useInternalTime = false;

    readonly fixDigits = {
        position: 5,
        rotation: 12,
        timeNow: 3,
    }
    private _deltaTime = 0;
    private _lastTime = 0;
    private readonly _material: cc.PhysicsMaterial | null = null;

    private readonly raycastOptions: IRaycastOptions = {
        'groupIndex': -1,
        'queryTrigger': true,
        'maxDistance': Infinity
    }

    private readonly raycastResultPool = new cc.RecyclePool(() => {
        return new PhysicsRayResult();
    }, 1);

    private constructor () {
        cc.director._scheduler && cc.director._scheduler.enableForTarget(this);
        this.physicsWorld = createPhysicsWorld();
        this._lastTime = performance.now();
        if (!CC_PHYSICS_BUILTIN) {
            this.gravity = this._gravity;
            this.allowSleep = this._allowSleep;
            this._material = new PhysicsMaterial();
            this._material.friction = 0.1;
            this._material.restitution = 0.1;
            this._material.on('physics_material_update', this._updateMaterial, this);
            this.physicsWorld.defaultMaterial = this._material;
        }
    }

    /**
     * !#en
     * A physical system simulation is performed once and will now be performed automatically once per frame.
     * !#zh
     * 执行一次物理系统的模拟，目前将在每帧自动执行一次。
     * @method update
     * @param {number} deltaTime The time difference from the last execution is currently elapsed per frame
     */
    update (deltaTime: number) {
        if (CC_EDITOR) {
            return;
        }
        if (!this._enabled) {
            return;
        }

        if (this.useInternalTime) {
            var now = parseFloat(performance.now().toFixed(this.fixDigits.timeNow));
            this._deltaTime = now > this._lastTime ? (now - this._lastTime) / 1000 : 0;
            this._lastTime = now;
        } else {
            this._deltaTime = deltaTime;
        }

        cc.director.emit(cc.Director.EVENT_BEFORE_PHYSICS);

        if (CC_PHYSICS_BUILTIN) {
            this.physicsWorld.step(this._fixedTime);
        } else {
            if (this._useFixedTime) {
                this.physicsWorld.step(this._fixedTime);
            } else {
                if (this.useAccumulator) {
                    let i = 0;
                    this._accumulator += this._deltaTime;
                    while (i < this._maxSubStep && this._accumulator > this._fixedTime) {
                        this.physicsWorld.step(this._fixedTime);
                        this._accumulator -= this._fixedTime;
                        i++;
                    }
                } else {
                    this.physicsWorld.step(this._fixedTime, this._deltaTime, this._maxSubStep);
                }
            }
        }

        cc.director.emit(cc.Director.EVENT_AFTER_PHYSICS);
    }

    /**
     * !#en Detect all collision boxes and return all detected results, or null if none is detected. Note that the return value is taken from the object pool, so do not save the result reference or modify the result.
     * !#zh 检测所有的碰撞盒，并返回所有被检测到的结果，若没有检测到，则返回空值。注意返回值是从对象池中取的，所以请不要保存结果引用或者修改结果。
     * @method raycast
     * @param {Ray} worldRay A ray in world space
     * @param {number|string} groupIndexOrName Collision group index or group name
     * @param {number} maxDistance Maximum detection distance
     * @param {boolean} queryTrigger Detect trigger or not
     * @return {PhysicsRayResult[] | null} Detected result
     */
    raycast (worldRay: cc.geomUtils.Ray, groupIndexOrName: number | string = 0, maxDistance = Infinity, queryTrigger = true): PhysicsRayResult[] | null {
        this.raycastResultPool.reset();
        this.raycastResults.length = 0;
        if (typeof groupIndexOrName == "string") {
            let groupIndex = cc.game.groupList.indexOf(groupIndexOrName);
            if (groupIndex == -1) groupIndex = 0;
            this.raycastOptions.groupIndex = groupIndex;
        } else {
            this.raycastOptions.groupIndex = groupIndexOrName;
        }
        this.raycastOptions.maxDistance = maxDistance;
        this.raycastOptions.queryTrigger = queryTrigger;
        let result = this.physicsWorld.raycast(worldRay, this.raycastOptions, this.raycastResultPool, this.raycastResults);
        if (result) return this.raycastResults;
        return null;
    }

    /**
     * !#en Detect all collision boxes and return the detection result with the shortest ray distance. If not, return null value. Note that the return value is taken from the object pool, so do not save the result reference or modify the result.
     * !#zh 检测所有的碰撞盒，并返回射线距离最短的检测结果，若没有，则返回空值。注意返回值是从对象池中取的，所以请不要保存结果引用或者修改结果。
     * @method raycastClosest
     * @param {Ray} worldRay A ray in world space
     * @param {number|string} groupIndexOrName Collision group index or group name
     * @param {number} maxDistance Maximum detection distance
     * @param {boolean} queryTrigger Detect trigger or not
     * @return {PhysicsRayResult|null} Detected result
     */
    raycastClosest (worldRay: cc.geomUtils.Ray, groupIndexOrName: number | string = 0, maxDistance = Infinity, queryTrigger = true): PhysicsRayResult | null {
        if (typeof groupIndexOrName == "string") {
            let groupIndex = cc.game.groupList.indexOf(groupIndexOrName);
            if (groupIndex == -1) groupIndex = 0;
            this.raycastOptions.groupIndex = groupIndex;
        } else {
            this.raycastOptions.groupIndex = groupIndexOrName;
        }
        this.raycastOptions.maxDistance = maxDistance;
        this.raycastOptions.queryTrigger = queryTrigger;
        let result = this.physicsWorld.raycastClosest(worldRay, this.raycastOptions, this.raycastClosestResult);
        if (result) return this.raycastClosestResult;
        return null;
    }

    private _updateMaterial () {
        if (!CC_PHYSICS_BUILTIN) {
            this.physicsWorld.defaultMaterial = this._material;
        }
    }
}