From e4095552c2e102ae704bba041e6bf6e0f3ac8cba Mon Sep 17 00:00:00 2001
From: Bjorn Winckler <bjorn.winckler@gmail.com>
Date: Sun, 18 Mar 2012 21:15:43 +0100
Subject: [PATCH] Avoid spurious inertial trackpad scrolling

When 'inertia' is enabled the trackpad sometimes sends events that tells
Vim to scroll zero lines.  Ignore such events, else Vim sometimes seems
to scroll a little bit too far.
---
 src/MacVim/MMBackend.m | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/MacVim/MMBackend.m b/src/MacVim/MMBackend.m
index c6645ddef0..111d07e64b 100644
--- a/src/MacVim/MMBackend.m
+++ b/src/MacVim/MMBackend.m
@@ -1880,13 +1880,13 @@ static void netbeansReadCallback(CFSocketRef s,
 
         int numLines = (dy != 0) ? (int)round(dy) : (int)round(dx);
         if (numLines < 0) numLines = -numLines;
-        if (numLines == 0) numLines = 1;
 
+        if (numLines != 0) {
 #ifdef FEAT_GUI_SCROLL_WHEEL_FORCE
-        gui.scroll_wheel_force = numLines;
+            gui.scroll_wheel_force = numLines;
 #endif
-
-        gui_send_mouse_event(button, col, row, NO, flags);
+            gui_send_mouse_event(button, col, row, NO, flags);
+        }
 
 #ifdef FEAT_BEVAL
         if (p_beval && balloonEval) {