Add INDIC_SQUIGGLEPIXMAP as a faster version of INDIC_SQUIGGLE.

Based on work by Matthew Brush and Lex Trottman.

4 files changed, 37 insertions, 0 deletions

diff --git a/doc/ScintillaDoc.html b/doc/ScintillaDoc.html
index e0dc42bad..5e726b498 100644
--- a/doc/ScintillaDoc.html
+++ b/doc/ScintillaDoc.html
@@ -3811,6 +3811,17 @@ struct Sci_TextToFind {
               Not available for OS X Carbon.</td>
         </tr>
 
+        <tr>
+          <td align="left"><code>INDIC_SQUIGGLEPIXMAP</code></td>
+
+          <td align="center">13</td>
+
+          <td>A version of <code>INDIC_SQUIGGLE</code> that draws using a pixmap instead of
+	  as a series of line segments for performance.
+	  Measured to be between 3 and 6 times faster than <code>INDIC_SQUIGGLE</code> on GTK+.
+	  Apperance will not be as good as <code>INDIC_SQUIGGLE</code> on OS X in HiDPI mode.</td>
+        </tr>
+
       </tbody>
     </table>
 
diff --git a/include/Scintilla.h b/include/Scintilla.h
index 4d467a175..63fe4fff5 100644
--- a/include/Scintilla.h
+++ b/include/Scintilla.h
@@ -262,6 +262,7 @@ typedef sptr_t (*SciFnDirect)(sptr_t ptr, unsigned int iMessage, uptr_t wParam,
 #define INDIC_DOTS 10
 #define INDIC_SQUIGGLELOW 11
 #define INDIC_DOTBOX 12
+#define INDIC_SQUIGGLEPIXMAP 13
 #define INDIC_MAX 31
 #define INDIC_CONTAINER 8
 #define INDIC0_MASK 0x20
diff --git a/include/Scintilla.iface b/include/Scintilla.iface
index e31863cfd..138730e61 100644
--- a/include/Scintilla.iface
+++ b/include/Scintilla.iface
@@ -578,6 +578,7 @@ val INDIC_DASH=9
 val INDIC_DOTS=10
 val INDIC_SQUIGGLELOW=11
 val INDIC_DOTBOX=12
+val INDIC_SQUIGGLEPIXMAP=13
 val INDIC_MAX=31
 val INDIC_CONTAINER=8
 val INDIC0_MASK=0x20
diff --git a/src/Indicator.cxx b/src/Indicator.cxx
index bd17c3d1c..7eab44433 100644
--- a/src/Indicator.cxx
+++ b/src/Indicator.cxx
@@ -18,6 +18,11 @@
 using namespace Scintilla;
 #endif
 
+static PRectangle PixelGridAlign(const PRectangle &rc) {
+	// Move left and right side to nearest pixel to avoid blurry visuals
+	return PRectangle(int(rc.left + 0.5), rc.top, int(rc.right + 0.5), rc.bottom);
+}
+
 void Indicator::Draw(Surface *surface, const PRectangle &rc, const PRectangle &rcLine) {
 	surface->PenColour(fore);
 	int ymid = (rc.bottom + rc.top) / 2;
@@ -31,6 +36,25 @@ void Indicator::Draw(Surface *surface, const PRectangle &rc, const PRectangle &r
 			y = 2 - y;
 		}
 		surface->LineTo(rc.right, rc.top + y);	// Finish the line
+	} else if (style == INDIC_SQUIGGLEPIXMAP) {
+		PRectangle rcSquiggle = PixelGridAlign(rc);
+
+		int width = Platform::Minimum(4000, rcSquiggle.Width());
+		RGBAImage image(width, 3, 1.0, 0);
+		enum { alphaFull = 0xff, alphaSide = 0x2f, alphaSide2=0x5f };
+		for (int x = 0; x < width; x++) {
+			if (x%2) {
+				// Two halfway columns have a full pixel in middle flanked by light pixels
+				image.SetPixel(x, 0, fore, alphaSide);
+				image.SetPixel(x, 1, fore, alphaFull);
+				image.SetPixel(x, 2, fore, alphaSide);
+			} else {
+				// Extreme columns have a full pixel at bottom or top and a mid-tone pixel in centre
+				image.SetPixel(x, (x%4) ? 0 : 2, fore, alphaFull);
+				image.SetPixel(x, 1, fore, alphaSide2);
+			}
+		}
+		surface->DrawRGBAImage(rcSquiggle, image.GetWidth(), image.GetHeight(), image.Pixels());
 	} else if (style == INDIC_SQUIGGLELOW) {
 		surface->MoveTo(rc.left, rc.top);
 		int x = rc.left + 3;