hobgoblin/src/loader.js

A framework for writing roguelike games in JavaScript, implementing ROT.js

// Game.Loader is a simple utility to track modules as they load (for the purpose of a load screen or some such).
// The loader can be initialized with an arbitrary list of module names. Additional modules
// can be `register`ed to the loader instance, as well as sub-modules.
Game.Loader = function(modules) {
    this.modules = {};
    for (var i = 0; i < modules.length; i++) {
        this.modules[modules[i]] = {
            submodules: {},
            progress: 0
        };
    }
    this.totalProgress = 0;
    this.currentlyLoading = [];
};
Game.Loader.prototype.getProgress = function() {
    return this.totalProgress;
};
Game.Loader.prototype.registerModule = function(module, submodule) {
    if(module in this.modules === false) {
        this.modules[module] = {
            submodules: {},
            progress: 0
        };
    } else if(submodule in this.modules[module].submodules === false) {
        this.modules[module].submodules[submodule] = {
            progress: 0
        };
    }
};
Game.Loader.prototype.startModule = function(module) {
    if(this.currentlyLoading.indexOf(module) === -1)
        this.currentlyLoading.push(module);
};
Game.Loader.prototype.startSubmodule = function(module, submodule) {
    if(this.currentlyLoading.indexOf(module) === -1)
        throw new Error("'" + module + "' is not currently loading.");
    if(this.currentlyLoading.indexOf(submodule) === -1)
        this.currentlyLoading.push(submodule);
};
Game.Loader.prototype.finishModule = function(module) {
    if(module in this.modules === false)
        throw new Error("'" + module + "' is not a registered module");

    // Make progress 100
    this.modules[module].progress = 100;

    // Remove item from currently loading list
    var index = this.currentlyLoading.indexOf(module);
    this.currentlyLoading.splice(index, 1);

    this._updateProgress();
};
Game.Loader.prototype.finishSubmodule = function(module, submodule) {
    if(this.currentlyLoading.indexOf(module) === -1)
        throw new Error("'" + module + "' is not currently loading.");
    else if(this.currentlyLoading.indexOf(submodule) === -1)
        throw new Error("'" + submodule + "' is not currently loading");
    else if(module in this.modules === false)
        throw new Error("'" + module + "' is not a registered module");
    else if(submodule in this.modules[module].submodules === false)
        throw new Error("'" + submodule + "' is not a registered submodule of '" + module + "'");

    this.modules[module].submodules[submodule].progress = 100;
    var index = this.currentlyLoading.indexOf(submodule);
    this.currentlyLoading.splice(index, 1);

    this._updateProgress();
};
Game.Loader.prototype.updateModule = function(module, amount) {
    if(module in this.modules === false)
        throw new Error("'" + module + "' is not a registered module");

    this.modules[module].progress = amount;

    this._updateProgress();
};
Game.Loader.prototype.updateSubmodule = function(module, submodule, amount) {
    if(module in this.modules === false)
        throw new Error("'" + module + "' is not a registered module");
    else if(submodule in this.modules[module].submodules === false)
        throw new Error("'" + submodule + "' is not a submodule of '" + module + "'");

    this.modules[module].submodules[submodule].progress = amount;

    // Update module progress as a function of the submodule's progress
    var numSubmodules = Object.keys(this.modules[module].submodules).length,
        maxProgress = numSubmodules * 100,
        currentProgress = 0;

    for(var sm in this.modules[module].submodules)
        currentProgress += this.modules[module].submodules[sm].progress;

    this.modules[module].progress = (currentProgress / maxProgress) * 100;

    this._updateProgress();
};
Game.Loader.prototype._updateProgress = function() {
    var numModules = Object.keys(this.modules).length,
        maxProgress = numModules * 100,
        currentProgress = 0,
        submodules, moduleMaxProgress, moduleProgress;

    for(var module in this.modules) {
        submodules = Object.keys(this.modules[module].submodules);
        moduleMaxProgress = submodules.length * 100;
        moduleProgress = 0;
        if(submodules.length) {
            for(var submodule in this.modules[module].submodules) {
                moduleProgress +=  this.modules[module].submodules[submodule].progress
            }

            this.modules[module].progress = (moduleProgress / moduleMaxProgress) * 100;
        }

        currentProgress += this.modules[module].progress;
    }

    for(var module in this.modules)
        currentProgress += this.modules[module].progress;

    this.totalProgress = (currentProgress / maxProgress) * 100;
};