From 123e361f5505254bcf202d25cf3acd7e0e207d1e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Wed, 2 Sep 2015 11:36:36 +0200
Subject: [PATCH] [libinput] Pointer motion event compression

If we have multiple pointer motion events we compress it to just one.
---
 libinput/connection.cpp | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/libinput/connection.cpp b/libinput/connection.cpp
index 644979e428..3f732aa87f 100644
--- a/libinput/connection.cpp
+++ b/libinput/connection.cpp
@@ -219,7 +219,20 @@ void Connection::processEvents()
             }
             case LIBINPUT_EVENT_POINTER_MOTION: {
                 PointerEvent *pe = static_cast<PointerEvent*>(event.data());
-                emit pointerMotion(pe->delta(), pe->time());
+                QPointF delta = pe->delta();
+                quint32 latestTime = pe->time();
+                auto it = m_eventQueue.begin();
+                while (it != m_eventQueue.end()) {
+                    if ((*it)->type() == LIBINPUT_EVENT_POINTER_MOTION) {
+                        QScopedPointer<PointerEvent> p(static_cast<PointerEvent*>(*it));
+                        delta += p->delta();
+                        latestTime = p->time();
+                        it = m_eventQueue.erase(it);
+                    } else {
+                        break;
+                    }
+                }
+                emit pointerMotion(delta, latestTime);
                 break;
             }
             case LIBINPUT_EVENT_POINTER_MOTION_ABSOLUTE: {