From 301a9965638376a7edfb052ed8640a2f88290b81 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20H=C3=B6glund?= <fredrik@kde.org>
Date: Thu, 8 Jan 2015 07:12:20 +0100
Subject: [PATCH] glx: Fix the swap event filter for DRI3 drivers

The drawable field is set to the X drawable ID when the swap event is
synthesized by DRI2WireToEvent(), and the GLX drawable ID when the
event is received over the wire. The latter being the case with DRI3.

__glXWireToEvent() fixes this for Xlib clients by changing the field
to the X drawable ID. This doesn't work for xcb clients however,
so we have to expect the field to be set to either the X or the GLX
drawable ID.

BUG: 342582
---
 glxbackend.cpp | 13 ++++++++-----
 glxbackend.h   |  4 +++-
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/glxbackend.cpp b/glxbackend.cpp
index fc0046d9c3..78efa4ebc3 100644
--- a/glxbackend.cpp
+++ b/glxbackend.cpp
@@ -41,7 +41,6 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <QOpenGLContext>
 // system
 #include <unistd.h>
-#include <xcb/glx.h>
 
 #include <deque>
 #include <algorithm>
@@ -79,9 +78,10 @@ namespace std {
 namespace KWin
 {
 
-SwapEventFilter::SwapEventFilter(xcb_drawable_t drawable)
+SwapEventFilter::SwapEventFilter(xcb_drawable_t drawable, xcb_glx_drawable_t glxDrawable)
     : X11EventFilter(Xcb::Extensions::self()->glxEventBase() + XCB_GLX_BUFFER_SWAP_COMPLETE),
-      m_drawable(drawable)
+      m_drawable(drawable),
+      m_glxDrawable(glxDrawable)
 {
 }
 
@@ -90,7 +90,10 @@ bool SwapEventFilter::event(xcb_generic_event_t *event)
     xcb_glx_buffer_swap_complete_event_t *ev =
             reinterpret_cast<xcb_glx_buffer_swap_complete_event_t *>(event);
 
-    if (ev->drawable == m_drawable) {
+    // The drawable field is the X drawable when the event was synthesized
+    // by a WireToEvent handler, and the GLX drawable when the event was
+    // received over the wire
+    if (ev->drawable == m_drawable || ev->drawable == m_glxDrawable) {
         Compositor::self()->bufferSwapComplete();
         return true;
     }
@@ -192,7 +195,7 @@ void GlxBackend::init()
     }
 
     if (m_haveINTELSwapEvent) {
-        m_swapEventFilter = std::make_unique<SwapEventFilter>(window);
+        m_swapEventFilter = std::make_unique<SwapEventFilter>(window, glxWindow);
         glXSelectEvent(display(), glxWindow, GLX_BUFFER_SWAP_COMPLETE_INTEL_MASK);
     }
 
diff --git a/glxbackend.h b/glxbackend.h
index fba0a3459c..5fd0b0bd6a 100644
--- a/glxbackend.h
+++ b/glxbackend.h
@@ -22,6 +22,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "scene_opengl.h"
 #include "x11eventfilter.h"
 
+#include <xcb/glx.h>
 #include <memory>
 
 namespace KWin
@@ -44,11 +45,12 @@ public:
 class SwapEventFilter : public X11EventFilter
 {
 public:
-    SwapEventFilter(xcb_drawable_t drawable);
+    SwapEventFilter(xcb_drawable_t drawable, xcb_glx_drawable_t glxDrawable);
     bool event(xcb_generic_event_t *event) override;
 
 private:
     xcb_drawable_t m_drawable;
+    xcb_glx_drawable_t m_glxDrawable;
 };