Make grConvert optional as it vanished on Windows

3 files changed, 31 insertions, 21 deletions

diff --git a/ChangeLog b/ChangeLog
index 767fc23..fcd9305 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+commit f5b36dc73e7778091a08eaed51fd9d4f8677fbc1
+Author: Johannes Ranke <jranke@uni-bremen.de>
+Date:   2017-03-17 21:19:14 +0100
+
+    Support a common template for depictions
+
 commit 13c59928390dd38073c7664ea1d2961d11ba60e2
 Author: Johannes Ranke <jranke@uni-bremen.de>
 Date:   2017-03-15 15:16:34 +0100
diff --git a/DESCRIPTION b/DESCRIPTION
index c311ded..eb8cc73 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -2,7 +2,7 @@ Package: chents
 Type: Package
 Title: Chemical Entities as R Objects
 Version: 0.2-6
-Date: 2017-03-17
+Date: 2017-06-13
 Authors@R: c(person("Johannes", "Ranke", role = c("aut", "cre", "cph"), 
                     email = "jranke@uni-bremen.de"))
 Description: Utilities for dealing with chemical entities and associated
@@ -13,17 +13,17 @@ Description: Utilities for dealing with chemical entities and associated
 Imports:
     webchem,
     R6,
-    grImport,
-    grConvert,
     yaml
 Suggests:
     knitr,
     testthat,
-    PythonInR
+    PythonInR,
+    grImport,
+    grConvert
 License: GPL
 LazyLoad: yes
 LazyData: yes
 Encoding: UTF-8
 VignetteBuilder: knitr
 URL: http://cgit.jrwb.de/chents
-RoxygenNote: 5.0.1.9000
+RoxygenNote: 6.0.1
diff --git a/R/chent.R b/R/chent.R
index 192c6df..3e89e14 100644
--- a/R/chent.R
+++ b/R/chent.R
@@ -191,22 +191,26 @@ chent <- R6Class("chent",
         PythonInR::pyExec("d2d.DrawMolecule(mol)")
         PythonInR::pyExec("d2d.FinishDrawing()")
         self$svg <- PythonInR::pyGet("d2d.GetDrawingText()")
-        svgfile <- tempfile(fileext = ".svg")
-        writeLines(self$svg, svgfile)
-
-        # Convert to PostScript, remembering size properties
-        psfile <- tempfile(fileext = ".ps")
-        suppressMessages(grConvert::convertPicture(svgfile, psfile))
-        ps_font_line <- grep("Tm$", readLines(psfile), value = TRUE)[1]
-        ps_font_size <- gsub(" .*$", "", ps_font_line)
-        self$Pict_font_size = as.numeric(ps_font_size)
-
-        # Read in to create Picture
-        xmlfile <- tempfile(fileext = ".xml")
-        PostScriptTrace(psfile, outfilename = xmlfile)
-        unlink(paste0("capture", basename(psfile)))
-        self$Picture <- readPicture(xmlfile)
-        unlink(c(xmlfile, psfile, svgfile))
+
+        if (!requireNamespace("grConvert")) {
+          stop("grConvert is not available, self$Picture will not be created")
+        } else {
+          # Convert to PostScript, remembering size properties
+          svgfile <- tempfile(fileext = ".svg")
+          writeLines(self$svg, svgfile)
+          psfile <- tempfile(fileext = ".ps")
+          suppressMessages(grConvert::convertPicture(svgfile, psfile))
+          ps_font_line <- grep("Tm$", readLines(psfile), value = TRUE)[1]
+          ps_font_size <- gsub(" .*$", "", ps_font_line)
+          self$Pict_font_size = as.numeric(ps_font_size)
+
+          # Read in to create Picture
+          xmlfile <- tempfile(fileext = ".xml")
+          PostScriptTrace(psfile, outfilename = xmlfile)
+          unlink(paste0("capture", basename(psfile)))
+          self$Picture <- readPicture(xmlfile)
+          unlink(c(xmlfile, psfile, svgfile))
+        }
       }
     },
     get_chyaml = function(repo = c("wd", "local", "web"),