From 5af7d6771833a868b0956c49896a53ee68213e9c Mon Sep 17 00:00:00 2001
From: tildearrow <me@tildearrow.org>
Date: Sun, 30 Apr 2023 12:24:14 -0500
Subject: [PATCH] GUI: optimize sample editor?

---
 src/gui/sampleEdit.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/gui/sampleEdit.cpp b/src/gui/sampleEdit.cpp
index 3a8fae4b..2d0cea88 100644
--- a/src/gui/sampleEdit.cpp
+++ b/src/gui/sampleEdit.cpp
@@ -1171,8 +1171,12 @@ void FurnaceGUI::drawSampleEdit() {
                 if (y1>=availY) y1=availY-1;
                 if (y2<0) y2=0;
                 if (y2>=availY) y2=availY-1;
-                for (int j=y1; j<=y2; j++) {
-                  data[i+availX*(availY-j-1)]=lineColor;
+
+                const int s1=i+availX*(availY-y1-1);
+                const int s2=i+availX*(availY-y2-1);
+
+                for (int j=s2; j<=s1; j+=availX) {
+                  data[j]=lineColor;
                 }
                 if (totalAdvance>0) xCoarse++;
               } while ((totalAdvance--)>0);