From 08d5eba8d0f6a3fbe4ecf013806c6ddf6f452d78 Mon Sep 17 00:00:00 2001 From: Sam Lantinga Date: Thu, 6 Jun 2013 23:18:36 -0700 Subject: [PATCH] Fixed bug 1897 - CPU spike on Windows with WM_EVENT and OpenGL buckyballreaction On some Windows systems, when switching from fullscreen to windowed mode in my game, the CPU will spike and the application never shows the window again. See the part of the e-mail thread here: http://lists.libsdl.org/pipermail/sdl-libsdl.org/2013-June/088626.html I change the window by calling: SDL_SetWindowFullscreen(gScreenInfo.sdlWindow, SDL_FALSE); SDL_SetWindowSize(gScreenInfo.sdlWindow, sdlWindowWidth, sdlWindowHeight); which you can see in our source: https://code.google.com/p/bitfighter/source/browse/zap/VideoSystem.cpp#377 Then all of a sudden the application gets stuck in WIN_PumpEvents() in SDL_windowsevents.c. I turned on WMMSG_DEBUG and found that there was an endless stream of WM_EVENT messages. I also found that where WM_PAINT is being handled in the callback WIN_WindowProc(), ValidateRect is somehow not clearing, or it is persisting, the WM_EVENT message like it's supposed to (according to the docs). This may be a hardware issue. The issue has appeared on three different systems, one of them sporadically: - Windows XP SP3 running in VMware 9.0 (without VMWare 3D acceleration, but with the tools and drivers installed), Host: openSUSE 12.3 x86_64, NVidia NVS 3100M - Windows XP SP3 64bit running in VirtualBox, Host: Debian Wheezy (stable), Mobility Radeon HD 4100 (this was the sporadic one) - Windows 7 64 bit, Radeon 6770 --- src/video/windows/SDL_windowsevents.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/video/windows/SDL_windowsevents.c b/src/video/windows/SDL_windowsevents.c index dcd183d6f..ca799ff80 100644 --- a/src/video/windows/SDL_windowsevents.c +++ b/src/video/windows/SDL_windowsevents.c @@ -644,7 +644,7 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) { RECT rect; if (GetUpdateRect(hwnd, &rect, FALSE)) { - ValidateRect(hwnd, &rect); + ValidateRect(hwnd, NULL); SDL_SendWindowEvent(data->window, SDL_WINDOWEVENT_EXPOSED, 0, 0); }