Add SC_ELEMENT_FOLD_LINE to set the colour of fold lines.

6 files changed, 29 insertions, 7 deletions

diff --git a/doc/ScintillaDoc.html b/doc/ScintillaDoc.html
index 531fca5aa..511632937 100644
--- a/doc/ScintillaDoc.html
+++ b/doc/ScintillaDoc.html
@@ -128,7 +128,7 @@
 
     <h1>Scintilla Documentation</h1>
 
-    <p>Last edited 17 July 2021 NH</p>
+    <p>Last edited 29 July 2021 NH</p>
 
     <p style="background:#90F0C0">Scintilla 5 has moved the lexers from Scintilla into a new
     <a href="Lexilla.html">Lexilla</a> project.<br />
@@ -2395,8 +2395,8 @@ struct Sci_TextToFind {
      <b id="SCI_SETWHITESPACEBACK">SCI_SETWHITESPACEBACK(bool useSetting, <a class="jump" href="#colour">colour</a> back)</b><br />
      By default, the colour of visible white space is determined by the lexer in use. The
     foreground and/or background colour of all visible white space can be set globally, overriding
-    the lexer's colours with <a href="#SCI_SETELEMENTCOLOUR"><code>SC_ELEMENT_WHITE_SPACE</code></a>
-    and <a href="#SCI_SETELEMENTCOLOUR"><code>SC_ELEMENT_WHITE_SPACE_BACK</code></a>.
+    the lexer's colours with <a class="element" href="#SCI_SETELEMENTCOLOUR"><code>SC_ELEMENT_WHITE_SPACE</code></a>
+    and <a class="element" href="#SCI_SETELEMENTCOLOUR"><code>SC_ELEMENT_WHITE_SPACE_BACK</code></a>.
     .<br />
     <code>SCI_SETWHITESPACEFORE</code> and <code>SCI_SETWHITESPACEBACK</code> also
     change the white space colours but the element APIs are preferred with <code>SC_ELEMENT_WHITE_SPACE</code>
@@ -3496,6 +3496,14 @@ struct Sci_TextToFind {
            <td></td>
            <td>Background colour of active hot spot</td>
          </tr>
+         <tr class="section">
+           <th align="left"><code>SC_ELEMENT_FOLD_LINE</code></th>
+           <td>80</td>
+           <td>Translucent</td>
+           <td>All</td>
+           <td></td>
+           <td>Colour of fold lines</td>
+         </tr>
        </tbody>
      </table>
 
@@ -7007,6 +7015,7 @@ sptr_t CallScintilla(unsigned int iMessage, uptr_t wParam, sptr_t lParam){
      <a class="message" href="#SCI_SETAUTOMATICFOLD">SCI_SETAUTOMATICFOLD(int automaticFold)</a><br />
      <a class="message" href="#SCI_GETAUTOMATICFOLD">SCI_GETAUTOMATICFOLD &rarr; int</a><br />
      <a class="message" href="#SCI_SETFOLDFLAGS">SCI_SETFOLDFLAGS(int flags)</a><br />
+     <a class="element" href="#SC_ELEMENT_FOLD_LINE">SC_ELEMENT_FOLD_LINE : colouralpha</a><br />
      <a class="message" href="#SCI_GETLASTCHILD">SCI_GETLASTCHILD(line line, int level) &rarr; line</a><br />
      <a class="message" href="#SCI_GETFOLDPARENT">SCI_GETFOLDPARENT(line line) &rarr; line</a><br />
      <a class="message" href="#SCI_SETFOLDEXPANDED">SCI_SETFOLDEXPANDED(line line, bool
@@ -7086,9 +7095,14 @@ sptr_t CallScintilla(unsigned int iMessage, uptr_t wParam, sptr_t lParam){
     update to match your changes.
 
     <p><b id="SCI_SETFOLDFLAGS">SCI_SETFOLDFLAGS(int flags)</b><br />
+     <b id="SC_ELEMENT_FOLD_LINE">SC_ELEMENT_FOLD_LINE : colouralpha</b><br />
      In addition to showing markers in the folding margin, you can indicate folds to the user by
-    drawing lines in the text area. The lines are drawn in the foreground colour set for <a
-    class="message" href="#StyleDefinition"><code>STYLE_DEFAULT</code></a>. Bits set in
+    drawing lines in the text area.
+    The lines are drawn in the <a class="element" href="#SCI_SETELEMENTCOLOUR"><code>SC_ELEMENT_FOLD_LINE</code></a>
+    colour if set.
+    If it is not set then the foreground colour set for <a
+    class="message" href="#StyleDefinition"><code>STYLE_DEFAULT</code></a> is used.
+    Bits set in
     <code class="parameter">flags</code> determine where folding lines are drawn:<br />
     </p>
 
diff --git a/doc/ScintillaHistory.html b/doc/ScintillaHistory.html
index 1b88ebab1..f0c6ded0b 100644
--- a/doc/ScintillaHistory.html
+++ b/doc/ScintillaHistory.html
@@ -575,6 +575,9 @@
 	Released 26 July 2021.
 	</li>
 	<li>
+	Add SC_ELEMENT_FOLD_LINE to set the colour of fold lines.
+	</li>
+	<li>
 	Fix display of fold lines when wrapped so they are only drawn once per line, not on each subline.
 	</li>
 	<li>
diff --git a/include/Scintilla.h b/include/Scintilla.h
index 97fbd3be0..3af22dfc5 100644
--- a/include/Scintilla.h
+++ b/include/Scintilla.h
@@ -291,6 +291,7 @@ typedef sptr_t (*SciFnDirectStatus)(sptr_t ptr, unsigned int iMessage, uptr_t wP
 #define SC_ELEMENT_WHITE_SPACE_BACK 61
 #define SC_ELEMENT_HOT_SPOT_ACTIVE 70
 #define SC_ELEMENT_HOT_SPOT_ACTIVE_BACK 71
+#define SC_ELEMENT_FOLD_LINE 80
 #define SCI_SETELEMENTCOLOUR 2753
 #define SCI_GETELEMENTCOLOUR 2754
 #define SCI_RESETELEMENTCOLOUR 2755
diff --git a/include/Scintilla.iface b/include/Scintilla.iface
index cc7dedf36..d8a1bdec1 100644
--- a/include/Scintilla.iface
+++ b/include/Scintilla.iface
@@ -697,6 +697,7 @@ val SC_ELEMENT_WHITE_SPACE=60
 val SC_ELEMENT_WHITE_SPACE_BACK=61
 val SC_ELEMENT_HOT_SPOT_ACTIVE=70
 val SC_ELEMENT_HOT_SPOT_ACTIVE_BACK=71
+val SC_ELEMENT_FOLD_LINE=80
 
 # Set the colour of an element. Translucency (alpha) may or may not be significant
 # and this may depend on the platform. The alpha byte should commonly be 0xff for opaque.
diff --git a/include/ScintillaTypes.h b/include/ScintillaTypes.h
index 830ccadba..ab4a55131 100644
--- a/include/ScintillaTypes.h
+++ b/include/ScintillaTypes.h
@@ -180,6 +180,7 @@ enum class Element {
 	WhiteSpaceBack = 61,
 	HotSpotActive = 70,
 	HotSpotActiveBack = 71,
+	FoldLine = 80,
 };
 
 enum class Layer {
diff --git a/src/EditView.cxx b/src/EditView.cxx
index f4d37e221..7eea729fd 100644
--- a/src/EditView.cxx
+++ b/src/EditView.cxx
@@ -2289,19 +2289,21 @@ static void DrawFoldLines(Surface *surface, const EditModel &model, const ViewSt
 	const FoldLevel levelNext = model.pdoc->GetFoldLevel(line + 1);
 	if (LevelIsHeader(level) &&
 		(LevelNumber(level) < LevelNumber(levelNext))) {
+		const ColourRGBA foldLineColour = vsDraw.ElementColour(Element::FoldLine).value_or(
+			vsDraw.styles[StyleDefault].fore);
 		// Paint the line above the fold
 		if ((subLine == 0) &&
 			((expanded && (FlagSet(model.foldFlags, FoldFlag::LineBeforeExpanded)))
 			||
 			(!expanded && (FlagSet(model.foldFlags, FoldFlag::LineBeforeContracted))))) {
-			surface->FillRectangleAligned(Side(rcLine, Edge::top, 1.0), Fill(vsDraw.styles[StyleDefault].fore));
+			surface->FillRectangleAligned(Side(rcLine, Edge::top, 1.0), foldLineColour);
 		}
 		// Paint the line below the fold
 		if (lastSubLine &&
 			((expanded && (FlagSet(model.foldFlags, FoldFlag::LineAfterExpanded)))
 			||
 			(!expanded && (FlagSet(model.foldFlags, FoldFlag::LineAfterContracted))))) {
-			surface->FillRectangleAligned(Side(rcLine, Edge::bottom, 1.0), Fill(vsDraw.styles[StyleDefault].fore));
+			surface->FillRectangleAligned(Side(rcLine, Edge::bottom, 1.0), foldLineColour);
 		}
 	}
 }