Added comments to MouseWheelChanged function which explains how B_MOUSE_WHEEL_CHANGED behaves.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@5376 a95241bf-73f2-0310-859d-f6bbb57e9c96
2003-11-15 13:33:26 +00:00
parent 868de40a82
commit 89d164def7
1 changed files with 5 additions and 0 deletions
@@ -1033,6 +1033,11 @@ ShowImageView::KeyDown (const char * bytes, int32 numBytes)
 void
 ShowImageView::MouseWheelChanged(BMessage *msg)
 {
+	// The BeOS driver does not currently support
+	// X wheel scrolling, therefore, dx is zero.
+	// |dy| is the number of notches scrolled up or down.
+	// When the wheel is scrolled down (towards the user) dy > 0
+	// When the wheel is scrolled up (away from the user) dy < 0
 	const float kscrollBy = 40;
 	float dy, dx;
 	float x, y;