Mercurial > sdl-ios-xcode
view README @ 3485:e77a69aae239
Mason Wheeler to sdl
I updated SDL, and suddenly my SDL frames stopped working. They'd "initialize" full of gibberish, and I couldn't render anything to them. After a bit of digging, I found a problem: the renderer initialization routine in my SDL frame code wasn't getting called anymore.
procedure TSdlFrame.Paint;
begin
if SDL_SelectRenderer(FWindowID) = -1 then
CreateRenderer;
SDL_RenderPresent;
end;
function TSdlFrame.CreateRenderer: boolean;
const
pf: tagPIXELFORMATDESCRIPTOR = (nSize: sizeof(pf); nVersion: 1;
dwFlags: PFD_DRAW_TO_WINDOW or PFD_SUPPORT_OPENGL or PFD_DOUBLEBUFFER;
iPixelType: PFD_TYPE_RGBA; cColorBits: 24; cAlphaBits: 8;
iLayerType: PFD_MAIN_PLANE);
RENDERERS: array[TRendererType] of AnsiString = ('software', 'gdi', 'opengl', 'd3d');
var
pFormat: integer;
begin
if (SDL_SelectRenderer(FWindowID) = 0) then
begin
result := true;
Exit;
end;
if FRendererType = rtOpenGL then
begin
pFormat := ChoosePixelFormat(canvas.Handle, @pf);
if not SetPixelFormat(canvas.Handle, pFormat, @pf) then
outputDebugString(PChar(SysErrorMessage(GetLastError)));
if wglCreateContext(canvas.Handle) = 0 then
outputDebugString(PChar(SysErrorMessage(GetLastError)));
end;
if (SDL_CreateRenderer(FWindowID, SDL_RendererIndex(RENDERERS[FRendererType]), [sdlrPresentFlip3, sdlrAccelerated]) = 0) then
begin
SDL_ShowWindow(FWindowID);
assert(SDL_SetRenderDrawColor(0, 0, 0, 255) = 0);
FFlags := SDL_GetWindowFlags(FWindowID);
if assigned(FOnAvailable) then
FOnAvailable(self);
end
else outputDebugString(pChar(format('SDL_CreateRenderer failed: %s', [sdl_GetError])));
result := SDL_SelectRenderer(FWindowID) = 0;
end;
This is a critical issue. The Paint method gets called when the control receives a WM_PAINT message from Windows. I can't create the renderer before then, or it will fail and cause trouble. And when I do create it, it needs to be created with certain parameters. So imagine my surprise when I started debugging into the DLL and found that SDL_SelectRenderer was trying to be "helpful" by creating the renderer for me if it didn't already exist! Now not only does my initialization code not get called, I end up with the wrong renderer and so things don't render as expected when I try to use the window.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 24 Nov 2009 04:48:12 +0000 |
parents | 1ed5d432e468 |
children | 797b37c0c046 |
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Simple DirectMedia Layer (SDL) Version 1.2 --- http://www.libsdl.org/ This is the Simple DirectMedia Layer, a general API that provides low level access to audio, keyboard, mouse, joystick, 3D hardware via OpenGL, and 2D framebuffer across multiple platforms. The current version supports Linux, Windows, Windows CE, BeOS, MacOS, Mac OS X, FreeBSD, NetBSD, OpenBSD, BSD/OS, Solaris, IRIX, and QNX. The code contains support for AIX, OSF/Tru64, RISC OS, and SymbianOS, but these are not officially supported. SDL is written in C, but works with C++ natively, and has bindings to several other languages, including Ada, C#, Eiffel, Erlang, Euphoria, Guile, Haskell, Java, Lisp, Lua, ML, Objective C, Pascal, Perl, PHP, Pike, Pliant, Python, Ruby, and Smalltalk. This library is distributed under GNU LGPL version 2, which can be found in the file "COPYING". This license allows you to use SDL freely in commercial programs as long as you link with the dynamic library. The best way to learn how to use SDL is to check out the header files in the "include" subdirectory and the programs in the "test" subdirectory. The header files and test programs are well commented and always up to date. More documentation is available in HTML format in "docs/index.html", and a documentation wiki is available online at: http://www.libsdl.org/cgi/docwiki.cgi The test programs in the "test" subdirectory are in the public domain. Frequently asked questions are answered online: http://www.libsdl.org/faq.php If you need help with the library, or just want to discuss SDL related issues, you can join the developers mailing list: http://www.libsdl.org/mailing-list.php Enjoy! Sam Lantinga (slouken@libsdl.org)