function getComputedSlideSize( presentationWidth, presentationHeight ) {

		let width = config.width;
		let height = config.height;

		if( config.disableLayout ) {
			width = dom.slides.offsetWidth;
			height = dom.slides.offsetHeight;
		}

		const size = {
			// Slide size
			width: width,
			height: height,

			// Presentation size
			presentationWidth: presentationWidth || dom.wrapper.offsetWidth,
			presentationHeight: presentationHeight || dom.wrapper.offsetHeight
		};

		// Reduce available space by margin
		size.presentationWidth -= ( size.presentationWidth * config.margin );
		size.presentationHeight -= ( size.presentationHeight * config.margin );

		// Slide width may be a percentage of available width
		if( typeof size.width === 'string' && /%$/.test( size.width ) ) {
			size.width = parseInt( size.width, 10 ) / 100 * size.presentationWidth;
		}

		// Slide height may be a percentage of available height
		if( typeof size.height === 'string' && /%$/.test( size.height ) ) {
			size.height = parseInt( size.height, 10 ) / 100 * size.presentationHeight;
		}

		return size;

	}
Calculates the computed pixel size of our slides. These
values are based on the width and height configuration
options.

@param {number} [presentationWidth=dom.wrapper.offsetWidth]
@param {number} [presentationHeight=dom.wrapper.offsetHeight]