From 7cfd19b8d052ed99f3060d5cab1349ec33e162ad Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20D=C3=B6singer?= <stefan@codeweavers.com>
Date: Mon, 25 Aug 2014 19:57:42 +0200
Subject: wined3d: Add a comment about worker thread lag.

---
 dlls/wined3d/cs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/dlls/wined3d/cs.c b/dlls/wined3d/cs.c
index 44930c1..9b890ae 100644
--- a/dlls/wined3d/cs.c
+++ b/dlls/wined3d/cs.c
@@ -677,6 +677,14 @@ void wined3d_cs_emit_present(struct wined3d_cs *cs, struct wined3d_swapchain *sw
 
     cs->ops->submit(cs, sizeof(*op));
 
+    /* D3D10 documentation suggests that Windows allows the game to run
+     * 3 frames ahead of the GPU. Increasing this above 1 causes uneven
+     * animation in some games, most notably StarCraft II. The framerates
+     * don't show this problem. The issue is more noticable with vsync
+     * on, but also happens with vsync off.
+     *
+     * In Counter-Strike: Source a frame difference of 3 causes noticable
+     * input delay that makes the game unplayable. */
     while (pending > 1)
         pending = InterlockedCompareExchange(&cs->pending_presents, 0, 0);
 }
-- 
2.1.3

