Babylon.js/src/Misc/sceneOptimizer.ts

import { Scene, IDisposable } from "../scene";
import { EngineStore } from "../Engines/engineStore";
import { AbstractMesh } from "../Meshes/abstractMesh";
import { Mesh } from "../Meshes/mesh";
import { Nullable } from "../types";
import { Observer, Observable } from "./observable";

/**
 * Defines the root class used to create scene optimization to use with SceneOptimizer
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @returns description string
     */
    public getDescription(): string {
        return "";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        return true;
    }

    /**
     * Creates the SceneOptimization object
     * @param priority defines the priority of this optimization (0 by default which means first in the list)
     * @param desc defines the description associated with the optimization
     */
    constructor(
        /**
         * Defines the priority of this optimization (0 by default which means first in the list)
         */
        public priority: number = 0) {
    }
}

/**
 * Defines an optimization used to reduce the size of render target textures
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class TextureOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @returns description string
     */
    public getDescription(): string {
        return "Reducing render target texture size to " + this.maximumSize;
    }

    /**
     * Creates the TextureOptimization object
     * @param priority defines the priority of this optimization (0 by default which means first in the list)
     * @param maximumSize defines the maximum sized allowed for textures (1024 is the default value). If a texture is bigger, it will be scaled down using a factor defined by the step parameter
     * @param step defines the factor (0.5 by default) used to scale down textures bigger than maximum sized allowed.
     */
    constructor(
        /**
         * Defines the priority of this optimization (0 by default which means first in the list)
         */
        public priority: number = 0,
        /**
         * Defines the maximum sized allowed for textures (1024 is the default value). If a texture is bigger, it will be scaled down using a factor defined by the step parameter
         */
        public maximumSize: number = 1024,
        /**
         * Defines the factor (0.5 by default) used to scale down textures bigger than maximum sized allowed.
         */
        public step = 0.5) {
        super(priority);
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {

        var allDone = true;
        for (var index = 0; index < scene.textures.length; index++) {
            var texture = scene.textures[index];

            if (!texture.canRescale || (<any>texture).getContext) {
                continue;
            }

            var currentSize = texture.getSize();
            var maxDimension = Math.max(currentSize.width, currentSize.height);

            if (maxDimension > this.maximumSize) {
                texture.scale(this.step);
                allDone = false;
            }
        }

        return allDone;
    }
}

/**
 * Defines an optimization used to increase or decrease the rendering resolution
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class HardwareScalingOptimization extends SceneOptimization {
    private _currentScale = -1;
    private _directionOffset = 1;

    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Setting hardware scaling level to " + this._currentScale;
    }

    /**
     * Creates the HardwareScalingOptimization object
     * @param priority defines the priority of this optimization (0 by default which means first in the list)
     * @param maximumScale defines the maximum scale to use (2 by default)
     * @param step defines the step to use between two passes (0.5 by default)
     */
    constructor(
        /**
         * Defines the priority of this optimization (0 by default which means first in the list)
         */
        public priority: number = 0,
        /**
         * Defines the maximum scale to use (2 by default)
         */
        public maximumScale: number = 2,
        /**
         * Defines the step to use between two passes (0.5 by default)
         */
        public step: number = 0.25) {
        super(priority);
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        if (this._currentScale === -1) {
            this._currentScale = scene.getEngine().getHardwareScalingLevel();
            if (this._currentScale > this.maximumScale) {
                this._directionOffset = -1;
            }
        }

        this._currentScale += this._directionOffset * this.step;

        scene.getEngine().setHardwareScalingLevel(this._currentScale);

        return this._directionOffset === 1 ? this._currentScale >= this.maximumScale : this._currentScale <= this.maximumScale;
    }
}

/**
 * Defines an optimization used to remove shadows
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class ShadowsOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Turning shadows on/off";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        scene.shadowsEnabled = optimizer.isInImprovementMode;
        return true;
    }
}

/**
 * Defines an optimization used to turn post-processes off
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class PostProcessesOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Turning post-processes on/off";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        scene.postProcessesEnabled = optimizer.isInImprovementMode;
        return true;
    }
}

/**
 * Defines an optimization used to turn lens flares off
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class LensFlaresOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Turning lens flares on/off";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        scene.lensFlaresEnabled = optimizer.isInImprovementMode;
        return true;
    }
}

/**
 * Defines an optimization based on user defined callback.
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class CustomOptimization extends SceneOptimization {
    /**
     * Callback called to apply the custom optimization.
     */
    public onApply: (scene: Scene, optimizer: SceneOptimizer) => boolean;

    /**
     * Callback called to get custom description
     */
    public onGetDescription: () => string;

    /**
     * Gets a string describing the action executed by the current optimization
     * @returns description string
     */
    public getDescription(): string {
        if (this.onGetDescription) {
            return this.onGetDescription();
        }

        return "Running user defined callback";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        if (this.onApply) {
            return this.onApply(scene, optimizer);
        }
        return true;
    }
}

/**
 * Defines an optimization used to turn particles off
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class ParticlesOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Turning particles on/off";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        scene.particlesEnabled = optimizer.isInImprovementMode;
        return true;
    }
}

/**
 * Defines an optimization used to turn render targets off
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class RenderTargetsOptimization extends SceneOptimization {
    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Turning render targets off";
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer): boolean {
        scene.renderTargetsEnabled = optimizer.isInImprovementMode;
        return true;
    }
}

/**
 * Defines an optimization used to merge meshes with compatible materials
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class MergeMeshesOptimization extends SceneOptimization {
    private static _UpdateSelectionTree = false;

    /**
     * Gets or sets a boolean which defines if optimization octree has to be updated
     */
    public static get UpdateSelectionTree(): boolean {
        return MergeMeshesOptimization._UpdateSelectionTree;
    }

    /**
     * Gets or sets a boolean which defines if optimization octree has to be updated
     */
    public static set UpdateSelectionTree(value: boolean) {
        MergeMeshesOptimization._UpdateSelectionTree = value;
    }

    /**
     * Gets a string describing the action executed by the current optimization
     * @return description string
     */
    public getDescription(): string {
        return "Merging similar meshes together";
    }

    private _canBeMerged = (abstractMesh: AbstractMesh): boolean => {
        if (!(abstractMesh instanceof Mesh)) {
            return false;
        }

        var mesh = <Mesh>abstractMesh;

        if (mesh.isDisposed()) {
            return false;
        }

        if (!mesh.isVisible || !mesh.isEnabled()) {
            return false;
        }

        if (mesh.instances.length > 0) {
            return false;
        }

        if (mesh.skeleton || mesh.hasLODLevels) {
            return false;
        }

        return true;
    }

    /**
     * This function will be called by the SceneOptimizer when its priority is reached in order to apply the change required by the current optimization
     * @param scene defines the current scene where to apply this optimization
     * @param optimizer defines the current optimizer
     * @param updateSelectionTree defines that the selection octree has to be updated (false by default)
     * @returns true if everything that can be done was applied
     */
    public apply(scene: Scene, optimizer: SceneOptimizer, updateSelectionTree?: boolean): boolean {

        var globalPool = scene.meshes.slice(0);
        var globalLength = globalPool.length;

        for (var index = 0; index < globalLength; index++) {
            var currentPool = new Array<Mesh>();
            var current = globalPool[index];

            // Checks
            if (!this._canBeMerged(current)) {
                continue;
            }

            currentPool.push(<Mesh>current);

            // Find compatible meshes
            for (var subIndex = index + 1; subIndex < globalLength; subIndex++) {
                var otherMesh = globalPool[subIndex];

                if (!this._canBeMerged(otherMesh)) {
                    continue;
                }

                if (otherMesh.material !== current.material) {
                    continue;
                }

                if (otherMesh.checkCollisions !== current.checkCollisions) {
                    continue;
                }

                currentPool.push(<Mesh>otherMesh);
                globalLength--;

                globalPool.splice(subIndex, 1);

                subIndex--;
            }

            if (currentPool.length < 2) {
                continue;
            }

            // Merge meshes
            Mesh.MergeMeshes(currentPool, undefined, true);
        }

        // Call the octree system optimization if it is defined.
        const sceneAsAny = scene as any;
        if (sceneAsAny.createOrUpdateSelectionOctree) {
            if (updateSelectionTree != undefined) {
                if (updateSelectionTree) {
                    sceneAsAny.createOrUpdateSelectionOctree();
                }
            }
            else if (MergeMeshesOptimization.UpdateSelectionTree) {
                sceneAsAny.createOrUpdateSelectionOctree();
            }
        }

        return true;
    }
}

/**
 * Defines a list of options used by SceneOptimizer
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class SceneOptimizerOptions {
    /**
     * Gets the list of optimizations to apply
     */
    public optimizations = new Array<SceneOptimization>();

    /**
     * Creates a new list of options used by SceneOptimizer
     * @param targetFrameRate defines the target frame rate to reach (60 by default)
     * @param trackerDuration defines the interval between two checkes (2000ms by default)
     */
    constructor(
        /**
         * Defines the target frame rate to reach (60 by default)
         */
        public targetFrameRate: number = 60,
        /**
         * Defines the interval between two checkes (2000ms by default)
         */
        public trackerDuration: number = 2000) {
    }

    /**
     * Add a new optimization
     * @param optimization defines the SceneOptimization to add to the list of active optimizations
     * @returns the current SceneOptimizerOptions
     */
    public addOptimization(optimization: SceneOptimization): SceneOptimizerOptions {
        this.optimizations.push(optimization);
        return this;
    }

    /**
     * Add a new custom optimization
     * @param onApply defines the callback called to apply the custom optimization (true if everything that can be done was applied)
     * @param onGetDescription defines the callback called to get the description attached with the optimization.
     * @param priority defines the priority of this optimization (0 by default which means first in the list)
     * @returns the current SceneOptimizerOptions
     */
    public addCustomOptimization(onApply: (scene: Scene) => boolean, onGetDescription: () => string, priority: number = 0): SceneOptimizerOptions {
        let optimization = new CustomOptimization(priority);
        optimization.onApply = onApply;
        optimization.onGetDescription = onGetDescription;

        this.optimizations.push(optimization);
        return this;
    }

    /**
     * Creates a list of pre-defined optimizations aimed to reduce the visual impact on the scene
     * @param targetFrameRate defines the target frame rate (60 by default)
     * @returns a SceneOptimizerOptions object
     */
    public static LowDegradationAllowed(targetFrameRate?: number): SceneOptimizerOptions {
        var result = new SceneOptimizerOptions(targetFrameRate);

        var priority = 0;
        result.addOptimization(new MergeMeshesOptimization(priority));
        result.addOptimization(new ShadowsOptimization(priority));
        result.addOptimization(new LensFlaresOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new PostProcessesOptimization(priority));
        result.addOptimization(new ParticlesOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new TextureOptimization(priority, 1024));

        return result;
    }

    /**
     * Creates a list of pre-defined optimizations aimed to have a moderate impact on the scene visual
     * @param targetFrameRate defines the target frame rate (60 by default)
     * @returns a SceneOptimizerOptions object
     */
    public static ModerateDegradationAllowed(targetFrameRate?: number): SceneOptimizerOptions {
        var result = new SceneOptimizerOptions(targetFrameRate);

        var priority = 0;
        result.addOptimization(new MergeMeshesOptimization(priority));
        result.addOptimization(new ShadowsOptimization(priority));
        result.addOptimization(new LensFlaresOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new PostProcessesOptimization(priority));
        result.addOptimization(new ParticlesOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new TextureOptimization(priority, 512));

        // Next priority
        priority++;
        result.addOptimization(new RenderTargetsOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new HardwareScalingOptimization(priority, 2));

        return result;
    }

    /**
     * Creates a list of pre-defined optimizations aimed to have a big impact on the scene visual
     * @param targetFrameRate defines the target frame rate (60 by default)
     * @returns a SceneOptimizerOptions object
     */
    public static HighDegradationAllowed(targetFrameRate?: number): SceneOptimizerOptions {
        var result = new SceneOptimizerOptions(targetFrameRate);

        var priority = 0;
        result.addOptimization(new MergeMeshesOptimization(priority));
        result.addOptimization(new ShadowsOptimization(priority));
        result.addOptimization(new LensFlaresOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new PostProcessesOptimization(priority));
        result.addOptimization(new ParticlesOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new TextureOptimization(priority, 256));

        // Next priority
        priority++;
        result.addOptimization(new RenderTargetsOptimization(priority));

        // Next priority
        priority++;
        result.addOptimization(new HardwareScalingOptimization(priority, 4));

        return result;
    }
}

/**
 * Class used to run optimizations in order to reach a target frame rate
 * @description More details at http://doc.babylonjs.com/how_to/how_to_use_sceneoptimizer
 */
export class SceneOptimizer implements IDisposable {
    private _isRunning = false;
    private _options: SceneOptimizerOptions;
    private _scene: Scene;
    private _currentPriorityLevel = 0;
    private _targetFrameRate = 60;
    private _trackerDuration = 2000;
    private _currentFrameRate = 0;
    private _sceneDisposeObserver: Nullable<Observer<Scene>>;
    private _improvementMode = false;

    /**
     * Defines an observable called when the optimizer reaches the target frame rate
     */
    public onSuccessObservable = new Observable<SceneOptimizer>();
    /**
     * Defines an observable called when the optimizer enables an optimization
     */
    public onNewOptimizationAppliedObservable = new Observable<SceneOptimization>();
    /**
     * Defines an observable called when the optimizer is not able to reach the target frame rate
     */
    public onFailureObservable = new Observable<SceneOptimizer>();

    /**
     * Gets a boolean indicating if the optimizer is in improvement mode
     */
    public get isInImprovementMode(): boolean {
        return this._improvementMode;
    }

    /**
     * Gets the current priority level (0 at start)
     */
    public get currentPriorityLevel(): number {
        return this._currentPriorityLevel;
    }

    /**
     * Gets the current frame rate checked by the SceneOptimizer
     */
    public get currentFrameRate(): number {
        return this._currentFrameRate;
    }

    /**
     * Gets or sets the current target frame rate (60 by default)
     */
    public get targetFrameRate(): number {
        return this._targetFrameRate;
    }

    /**
     * Gets or sets the current target frame rate (60 by default)
     */
    public set targetFrameRate(value: number) {
        this._targetFrameRate = value;
    }

    /**
     * Gets or sets the current interval between two checks (every 2000ms by default)
     */
    public get trackerDuration(): number {
        return this._trackerDuration;
    }

    /**
     * Gets or sets the current interval between two checks (every 2000ms by default)
     */
    public set trackerDuration(value: number) {
        this._trackerDuration = value;
    }

    /**
     * Gets the list of active optimizations
     */
    public get optimizations(): SceneOptimization[] {
        return this._options.optimizations;
    }

    /**
     * Creates a new SceneOptimizer
     * @param scene defines the scene to work on
     * @param options defines the options to use with the SceneOptimizer
     * @param autoGeneratePriorities defines if priorities must be generated and not read from SceneOptimization property (true by default)
     * @param improvementMode defines if the scene optimizer must run the maximum optimization while staying over a target frame instead of trying to reach the target framerate (false by default)
     */
    public constructor(scene: Scene, options?: SceneOptimizerOptions, autoGeneratePriorities = true, improvementMode = false) {
        if (!options) {
            this._options = new SceneOptimizerOptions();
        } else {
            this._options = options;
        }

        if (this._options.targetFrameRate) {
            this._targetFrameRate = this._options.targetFrameRate;
        }

        if (this._options.trackerDuration) {
            this._trackerDuration = this._options.trackerDuration;
        }

        if (autoGeneratePriorities) {
            let priority = 0;
            for (var optim of this._options.optimizations) {
                optim.priority = priority++;
            }
        }

        this._improvementMode = improvementMode;
        this._scene = scene || EngineStore.LastCreatedScene;
        this._sceneDisposeObserver = this._scene.onDisposeObservable.add(() => {
            this._sceneDisposeObserver = null;
            this.dispose();
        });
    }

    /**
     * Stops the current optimizer
     */
    public stop() {
        this._isRunning = false;
    }

    /**
     * Reset the optimizer to initial step (current priority level = 0)
     */
    public reset() {
        this._currentPriorityLevel = 0;
    }

    /**
     * Start the optimizer. By default it will try to reach a specific framerate
     * but if the optimizer is set with improvementMode === true then it will run all optimiatiation while frame rate is above the target frame rate
     */
    public start() {
        if (this._isRunning) {
            return;
        }

        this._isRunning = true;

        // Let's wait for the scene to be ready before running our check
        this._scene.executeWhenReady(() => {
            setTimeout(() => {
                this._checkCurrentState();
            }, this._trackerDuration);
        });
    }

    private _checkCurrentState() {
        if (!this._isRunning) {
            return;
        }

        let scene = this._scene;
        let options = this._options;

        this._currentFrameRate = Math.round(scene.getEngine().getFps());

        if (this._improvementMode && this._currentFrameRate <= this._targetFrameRate ||
            !this._improvementMode && this._currentFrameRate >= this._targetFrameRate) {
            this._isRunning = false;
            this.onSuccessObservable.notifyObservers(this);
            return;
        }

        // Apply current level of optimizations
        var allDone = true;
        var noOptimizationApplied = true;
        for (var index = 0; index < options.optimizations.length; index++) {
            var optimization = options.optimizations[index];

            if (optimization.priority === this._currentPriorityLevel) {
                noOptimizationApplied = false;
                allDone = allDone && optimization.apply(scene, this);
                this.onNewOptimizationAppliedObservable.notifyObservers(optimization);
            }
        }

        // If no optimization was applied, this is a failure :(
        if (noOptimizationApplied) {
            this._isRunning = false;
            this.onFailureObservable.notifyObservers(this);

            return;
        }

        // If all optimizations were done, move to next level
        if (allDone) {
            this._currentPriorityLevel++;
        }

        // Let's the system running for a specific amount of time before checking FPS
        scene.executeWhenReady(() => {
            setTimeout(() => {
                this._checkCurrentState();
            }, this._trackerDuration);
        });
    }

    /**
     * Release all resources
     */
    public dispose(): void {
        this.stop();
        this.onSuccessObservable.clear();
        this.onFailureObservable.clear();
        this.onNewOptimizationAppliedObservable.clear();
        if (this._sceneDisposeObserver) {
            this._scene.onDisposeObservable.remove(this._sceneDisposeObserver);
        }
    }

    /**
     * Helper function to create a SceneOptimizer with one single line of code
     * @param scene defines the scene to work on
     * @param options defines the options to use with the SceneOptimizer
     * @param onSuccess defines a callback to call on success
     * @param onFailure defines a callback to call on failure
     * @returns the new SceneOptimizer object
     */
    public static OptimizeAsync(scene: Scene, options?: SceneOptimizerOptions, onSuccess?: () => void, onFailure?: () => void): SceneOptimizer {
        let optimizer = new SceneOptimizer(scene, options || SceneOptimizerOptions.ModerateDegradationAllowed(), false);

        if (onSuccess) {
            optimizer.onSuccessObservable.add(() => {
                onSuccess();
            });
        }

        if (onFailure) {
            optimizer.onFailureObservable.add(() => {
                onFailure();
            });
        }

        optimizer.start();

        return optimizer;
    }
}