feat(webshot): Round v{width,height} to nearest integer

DESCRIPTION

@@ -28,4 +28,4 @@ Suggests:
     shiny
 Encoding: UTF-8
 Language: en-US
-RoxygenNote: 7.2.3
+RoxygenNote: 7.3.2

NEWS.md

@@ -1,5 +1,7 @@
 # webshot2 (development version)
 
+* `webshot()` now rounds `vwidth` and `vheight` to the nearest integer to match Chrome's expectations. If this behavior is somehow problematic, you can use `vwidth = I(my_width)` to avoid the conversion. (#70)
+
 # webshot2 0.1.1
 
 * `webshot()` now supports JPEG (`.jpg` or `.jpeg`) and WEBP (`.webp`) image formats. (@trafficonese #45)

R/utils.R

@@ -1,3 +1,7 @@
+as_rounded_int <- function(x) {
+  if (inherits(x, "AsIs")) x else round(x, digits = 0)
+}
+
 # =============================================================================
 # System
 # =============================================================================

R/webshot.R

@@ -16,8 +16,9 @@ NULL
 #'   to the file name. For PDF output, it is just like printing the page to PDF
 #'   in a browser; \code{selector}, \code{cliprect}, \code{expand}, and
 #'   \code{zoom} will not be used for PDFs.
-#' @param vwidth Viewport width. This is the width of the browser "window".
-#' @param vheight Viewport height This is the height of the browser "window".
+#' @param vwidth,vheight Viewport width and height. This is the width or height
+#'   of the virtual browser "window". Chrome expects integer values; numeric
+#'   values are rounded to the nearest integer.
 #' @param selector One or more CSS selectors specifying a DOM element to set the
 #'   clipping rectangle to. The screenshot will contain these DOM elements. For
 #'   a given selector, if it has more than one match, all matching elements will
@@ -164,8 +165,8 @@ webshot <- function(
   args_all <- list(
     url       = url,
     file      = file,
-    vwidth    = vwidth,
-    vheight   = vheight,
+    vwidth    = as_rounded_int(vwidth), # Chrome requires integer viewport pxs
+    vheight   = as_rounded_int(vheight),
     selector  = selector,
     cliprect  = cliprect,
     expand    = expand,