Revert "remove pdf height offset"

This reverts commit f76b4fda93a8d8770390d4e89b68f8ac27e32dc9.

js/reveal.js

@@ -196,6 +196,13 @@
 			// to PDF, unlimited by default
 			pdfMaxPagesPerSlide: Number.POSITIVE_INFINITY,
 
+			// Offset used to reduce the height of content within exported PDF pages.
+			// This exists to account for environment differences based on how you
+			// print to PDF. CLI printing options, like phantomjs and wkpdf, can end
+			// on precisely the total height of the document whereas in-browser
+			// printing has to end one pixel before.
+			pdfPageHeightOffset: -1,
+
 			// Number of slides away from the current that are visible
 			viewDistance: 3,
 
@@ -661,8 +668,8 @@
 		var slideSize = getComputedSlideSize( window.innerWidth, window.innerHeight );
 
 		// Dimensions of the PDF pages
-		var pageWidth = Math.ceil( slideSize.width * ( 1 + config.margin ) ),
-			pageHeight = Math.ceil( slideSize.height * ( 1 + config.margin ) );
+		var pageWidth = Math.floor( slideSize.width * ( 1 + config.margin ) ),
+			pageHeight = Math.floor( slideSize.height * ( 1 + config.margin ) );
 
 		// Dimensions of slides within the pages
 		var slideWidth = slideSize.width,
@@ -719,7 +726,7 @@
 				// so that no page ever flows onto another
 				var page = document.createElement( 'div' );
 				page.className = 'pdf-page';
-				page.style.height = ( pageHeight * numberOfPages ) + 'px';
+				page.style.height = ( ( pageHeight + config.pdfPageHeightOffset ) * numberOfPages ) + 'px';
 				slide.parentNode.insertBefore( page, slide );
 				page.appendChild( slide );