shaku/src/assets/texture_in_atlas_asset.js

A simple and effective JavaScript game development framework that knows its place!

/**
 * Implement texture asset type.
 * 
 * |-- copyright and license --|
 * @module     Shaku
 * @file       shaku\src\assets\texture_in_atlas_asset.js
 * @author     Ronen Ness (ronenness@gmail.com | http://ronenness.com)
 * @copyright  (c) 2021 Ronen Ness
 * @license    MIT
 * |-- end copyright and license --|
 * 
 */
'use strict';
const TextureAssetBase = require("./texture_asset_base");
const Rectangle = require("../utils/rectangle");


/**
 * A texture that is part of a texture atlas.
 * Stores a texture that was generated by the texture atlas + the source rectangle in texture for this segment.
 */
class TextureInAtlasAsset extends TextureAssetBase
{
    /** @inheritdoc */
    constructor(url, texture, sourceRect, atlas)
    {
        super(url);
        this._texture = texture;
        this._sourceRect = sourceRect;
        this._atlas = atlas;
    }

    /**
     * Return the source rectangle in texture atlas.
     * @returns {Rectangle} Source rectangle.
     */
    get sourceRectangle()
    {
        return this._sourceRect;
    }

    /**
     * Return the source rectangle in texture atlas, in normalized 0.0-1.0 values.
     * @returns {Rectangle} Source rectangle.
     */
    get sourceRectangleNormalized()
    {
        if (!this._sourceRectNormalized) {
            this._sourceRectNormalized = new Rectangle(
                this._sourceRect.x / this.width, 
                this._sourceRect.y / this.height, 
                this._sourceRect.width / this.width, 
                this._sourceRect.height / this.height
            );
        }
        return this._sourceRectNormalized;
    }

    /**
     * Return the texture asset of this atlas texture.
     * @returns {TextureAsset} Texture asset.
     */
    get texture()
    {
        return this._texture;
    }

    /**
     * Return the texture atlas class.
     * @returns {TextureAtlasAsset} Parent atlas.
     */
    get atlas()
    {
        return this._atlas;
    }

    /** @inheritdoc */
    get image()
    {
        return this.texture.image;
    }

    /** @inheritdoc */
    get width()
    {
        return this.texture.width;
    }

    /** @inheritdoc */
    get height()
    {
        return this.texture.height;
    }

    /** @inheritdoc */
    get _glTexture()
    {
        return this.texture._glTexture;
    }

    /** @inheritdoc */
    get valid()
    {
        return Boolean(this.texture.valid);
    }

    /** @inheritdoc */
    destroy()
    {
    }
}


// export the asset type.
module.exports = TextureInAtlasAsset;