r3-legacy/src/r3-d3-camera-orthographic-fixedAspect.js

/**
 * R3.D3.Camera.Orthographic.FixedAspect
 * @param apiComponent
 * @constructor
 */
R3.D3.Camera.Orthographic.FixedAspect = function(
	apiComponent
) {

    __RUNTIME_COMPONENT__;

    R3.D3.Camera.Orthographic.call(
        this,
        apiComponent,
        true
    );
    
};

R3.D3.Camera.Orthographic.FixedAspect.prototype = Object.create(R3.D3.Camera.Orthographic.prototype);
R3.D3.Camera.Orthographic.FixedAspect.prototype.constructor = R3.D3.Camera.Orthographic.FixedAspect;

/**
 * Creates a camera instance
 * @returns {*}
 */
R3.D3.Camera.Orthographic.FixedAspect.prototype.createInstance = function() {

    /**
     * We need to get the viewport width and height
     * @type {void|*}
     */

    var dimensions = this.getDimensions();

    this.instance = this.graphics.OrthographicCamera(
        dimensions.left,
        dimensions.right,
        dimensions.top,
        dimensions.bottom,
        this.near,
        this.far
    );

    __CREATE_INSTANCE__;
};

/**
 * Updates the instance with the current state
 */
R3.D3.Camera.Orthographic.FixedAspect.prototype.updateInstance = function(property) {

    if (property === 'aspect') {

        var dimensions = this.getDimensions();

        this.instance.left      = dimensions.left;
        this.instance.right     = dimensions.right;
        this.instance.top       = dimensions.top;
        this.instance.bottom    = dimensions.bottom;

        this.instance.updateProjectionMatrix();

        return;
    }

    R3.D3.Camera.Orthographic.prototype.updateInstance.call(this, property);
};

/**
 * This calculates the dimensions of the camera based on the following example info:
 *
 * aspect =  width
 *           ------
 *           height
 *
 * width    = aspect * height;
 * height   = width / aspect;
 *
 * aspect > 1 (width > height) (landscape)
 * aspect < 1 (height > width) (portrait)
 *
 * 4 / 3   = 1.33333 (1920 x 1440)
 * 16 / 9  = 1.77777 (1920 x 1080)
 *
 * w   h                w      h
 * 9 / 16  = 0.5625    (1080 x 1920) - required
 * 3 / 4   = 0.75      (1440 x 1920) - current
 *
 * @returns {{left: number, right: number, top: number, bottom: number}}
 */
R3.D3.Camera.Orthographic.FixedAspect.prototype.getDimensions = function() {


    var size = R3.Utils.GetWindowSize();

    var currentAspect = size.width / size.height;

    var width, height;

    if (currentAspect > 1) {
        /**
         * Width is greater than height (landscape)
         */
        if (this.aspectRatio < 1) {

            /**
             * The required aspect is more high than wide - use the full height
             */
            width   = this.aspectRatio * size.height;
            height  = size.height;

        } else {
            /**
             * The required aspect is also more wide than high - so we have another two possibilities:
             * a) The required aspect is greater than the current aspect - this means the required aspect is less high
             *    than the current aspect - we can use the full width
             *
             * b) The required aspect is less than the current aspect - this means the required aspect is higher than
             *    the current aspect - we need to determine a new width based on the current height
             */
            if (this.aspectRatio > currentAspect) {
                /**
                 * a)
                 */
                width   = size.width;
                height  = width / this.aspectRatio;
            } else {
                /**
                 * b)
                 */
                height  = size.height;
                width   = this.aspectRatio * height;
            }

        }

    } else {
        /**
         * The height is greater than the width (portrait)
         */
        if (this.aspectRatio > 1) {

            /**
             * The required aspect is landscape in a portrait mode - use the full width and calculate the new height
             */
            width   = size.width;
            height  = width / this.aspectRatio;

        } else {

            /**
             * The required aspect is also more high than wide (portrait) - we have again, two possibilities
             * a) The required aspect is greater than the current aspect - this means the required aspect does not fit
             *    the full width of the current aspect - use the full width of the current size and determine a new height
             *
             * b) The required aspect is less than the current aspect - this means that the required aspect is less wide
             *    than the current aspect, so we can use the full height of the current size and determine a new width
             */

            if (this.aspectRatio > currentAspect) {
                width   = size.width;
                height  = width / this.aspectRatio;
            } else {
                height = size.height;
                width   = this.aspectRatio * height;
            }

        }

    }

    /**
     * We now have the correct width and height of of the camera
     */
    return {
        left    : width  / -2,
        right   : width  /  2,
        top     : height /  2,
        bottom  : height / -2
    }

};