From 4739620afe768329f3f92d23608b395bb715a136 Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Thu, 23 Feb 2017 21:14:46 +0100
Subject: [PATCH] Special-case .stretch class for images in reveal.js.
Now in reveal.js, an image with class `stretch` in a paragraph
by itself will stretch to fill the whole screen, with no
caption or figure environment.
Closes #1291.
---
MANUAL.txt | 4 ++++
src/Text/Pandoc/Writers/HTML.hs | 27 +++++++++++++++++++++------
2 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/MANUAL.txt b/MANUAL.txt
index 0001c6cc1..81e3ad663 100644
--- a/MANUAL.txt
+++ b/MANUAL.txt
@@ -3072,6 +3072,10 @@ nonbreaking space after the image:
\
+Note that in reveal.js slide shows, an image in a paragraph
+by itself that has the `stretch` class will fill the screen,
+and the caption and figure tags will be omitted.
+
#### Extension: `link_attributes` ####
Attributes can be set on links and images:
diff --git a/src/Text/Pandoc/Writers/HTML.hs b/src/Text/Pandoc/Writers/HTML.hs
index 6661ffc2d..2afd84598 100644
--- a/src/Text/Pandoc/Writers/HTML.hs
+++ b/src/Text/Pandoc/Writers/HTML.hs
@@ -533,12 +533,10 @@ treatAsImage fp =
ext = map toLower $ drop 1 $ takeExtension path
in null ext || ext `elem` imageExts
--- | Convert Pandoc block element to HTML.
-blockToHtml :: PandocMonad m => WriterOptions -> Block -> StateT WriterState m Html
-blockToHtml _ Null = return mempty
-blockToHtml opts (Plain lst) = inlineListToHtml opts lst
--- title beginning with fig: indicates that the image is a figure
-blockToHtml opts (Para [Image attr txt (s,'f':'i':'g':':':tit)]) = do
+figure :: PandocMonad m
+ => WriterOptions -> Attr -> [Inline] -> (String, String)
+ -> StateT WriterState m Html
+figure opts attr txt (s,tit) = do
img <- inlineToHtml opts (Image attr txt (s,tit))
html5 <- gets stHtml5
let tocapt = if html5
@@ -552,6 +550,23 @@ blockToHtml opts (Para [Image attr txt (s,'f':'i':'g':':':tit)]) = do
[nl opts, img, capt, nl opts]
else H.div ! A.class_ "figure" $ mconcat
[nl opts, img, nl opts, capt, nl opts]
+
+-- | Convert Pandoc block element to HTML.
+blockToHtml :: PandocMonad m => WriterOptions -> Block -> StateT WriterState m Html
+blockToHtml _ Null = return mempty
+blockToHtml opts (Plain lst) = inlineListToHtml opts lst
+blockToHtml opts (Para [Image attr@(_,classes,_) txt (src,tit)])
+ | "stretch" `elem` classes = do
+ slideVariant <- gets stSlideVariant
+ case slideVariant of
+ RevealJsSlides ->
+ -- a "stretched" image in reveal.js must be a direct child
+ -- of the slide container
+ inlineToHtml opts (Image attr txt (src, tit))
+ _ -> figure opts attr txt (src, tit)
+-- title beginning with fig: indicates that the image is a figure
+blockToHtml opts (Para [Image attr txt (s,'f':'i':'g':':':tit)]) =
+ figure opts attr txt (s,tit)
blockToHtml opts (Para lst)
| isEmptyRaw lst = return mempty
| otherwise = do