Mercurial > sdl-ios-xcode
view VisualC.html @ 1287:15a89a0c52bf
Date: Tue, 15 Feb 2005 21:28:48 +0900 (JST)
From: "Michael Leonhard"
Subject: [SDL] resize bug on Win32 and patch
This is my first post to this mailing list. In this email I will detail a
bug in the behavior of resizable SDL windows on Win32. Then I will
explain the solution and provide a patch.
Symptoms:
Under Windows, an SDL display created with the SDL_RESIZABLE flag exhibits
quirky behavior when being maximized. The window is resized to the proper
size, but it is shifted upwards about half the height of the title bar.
Similarly, a window whose origin is above the top of the screen will
spontaneously move its upper-left origin upon being resized. After two
such resize-induced moves, the title bar will be entirely off the top edge
of the screen. Subsequently, when the mouse is clicked and released on
the window border, the window will shrink its height spontaneously. This
height shrinkage occurs even if the user did not resize the border.
To observe this curious situation, please invoke:
SDL-1.2.8/test/testwm.exe -resize
Cause:
A pair of integers, SDL_windowX and SDL_windowY, are defined in
video/wincommon/SDL_sysevents.c. They are used by the DirectX video
driver and the DIB video driver:
video/windx5/SDL_dx5video.c
video/windib/SDL_dibvideo.c
As I understand the source code, the primary use of these variables is to
create a rectangle that represents the surface area in CLIENT SPACE.
Client space refers to a coordinate system that originates at the upper
left corner of a Win32 Window's drawable area. This is just inside the
window border and title bar. This client space rectangle, called bounds,
is subsequently converted to screen space with a call to
AdjustWindowRectEx. The problem is found in SDL's handling of the
WM_WINDOWPOSCHANGED message. According to MSDN,
"The WM_WINDOWPOSCHANGED message is sent to a window whose
size, position, or place in the Z order has changed as a
result of a call to the SetWindowPos function or another
window-management function."
I have confirmed that this message is indeed being sent to the SDL window
when the mouse is clicked on the window border, even if the window border
is not dragged.
In video/wincommon/SDL_sysevents.c, on line 464, in response to the
WM_WINDOWPOSCHANGED message, the (potentially) new client rectangle is
obtained. This rectangle is translated into screen coordinates and THEN
assigned to the SDL_windowX and Y variables. Thus screen coordinates are
being assigned to client coordinate variables. Once this is understood,
the solution is apparent: assign SDL_windowX and Y before translating the
rectangle to screen coordinates. This is accomplished by the following
patch.
-Mike_L
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 29 Jan 2006 08:50:06 +0000 |
parents | e044e7c70a50 |
children | 4f896c20caf6 |
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<HTML> <HEAD> <TITLE>Using SDL with Microsoft Visual C++</TITLE> </HEAD> <BODY> <H1> Using SDL with Microsoft Visual C++ 5,6 and 7 </H1> <H3> by <A HREF="mailto:snowlion@sprynet.com">Lion Kimbro </A>and additions by <A HREF="mailto:james@conceptofzero.net"> James Turk</A> </H3> <p> You can either use the precompiled libraries from <A HREF="http://www.libsdl.org/download.php"> the SDL Download web site </A>, or you can build SDL yourself. </p> <H3> Building SDL </H3> <P> Unzip the <CODE>VisualC.zip</CODE> file into the directory that contains this file (<CODE>VisualC.html</CODE>). </P> <P> Be certain that you unzip the zip file for your compiler into <strong>this</strong> directory and not any other directory. If you are using WinZip, be careful to make sure that it extracts to <strong>this</strong> folder, because it's convenient feature of unzipping to a folder with the name of the file currently being unzipped will get you in trouble if you use it right now. And that's all I have to say about that. </P> <P> Now that it's unzipped, go into the VisualC directory that is created, and double-click on the VC++ file "<CODE>SDL.dsw</CODE>"<STRONG><FONT color="#009900"> ("<CODE>SDL.sln</CODE>").</FONT></STRONG> This should open up the IDE. </P> <P> You may be prompted at this point to upgrade the workspace, should you be using a more recent version of Visual C++. If so, allow the workspace to be upgraded. </P> <P> Build the <CODE>.dll</CODE> and <CODE>.lib</CODE> files. </P> <P> This is done by right clicking on each project in turn (Projects are listed in the Workspace panel in the FileView tab), and selecting "Build". </P> <P> You may get a few warnings, but you should not get any errors. You do have to have at least the DirectX 5 SDK installed, however. The latest version of DirectX can be downloaded or purchased on a cheap CD (my recommendation) from <A HREF="http://www.microsoft.com">Microsoft </A>. </P> <P> Later, we will refer to the following .lib and .dll files that have just been generated: </P> <ul> <li> SDL.dll</li> <li> SDL.lib</li> <li> SDLmain.lib</li> </ul> <P> Search for these using the Windows Find (Windows-F) utility, if you don't already know where they should be. For those of you with a clue, look inside the Debug or Release directories of the subdirectories of the Project folder. (It might be easier to just use Windows Find if this sounds confusing. And don't worry about needing a clue; we all need visits from the clue fairy frequently.) </P> <H3> Creating a Project with SDL </H3> <P> Create a project as a Win32 Application. </P> <P> Create a C++ file for your project. </P> <P> Set the C runtime to "Multi-threaded DLL" in the menu: <CODE>Project|Settings|C/C++ tab|Code Generation|Runtime Library </CODE>. </P> <P> Add the SDL <CODE>include</CODE> directory to your list of includes in the menu: <CODE>Project|Settings|C/C++ tab|Preprocessor|Additional include directories </CODE> . <br> <STRONG><FONT color="#009900">VC7 Specific: Instead of doing this I find it easier to add the include and library directories to the list that VC7 keeps. Do this by selecting Tools|Options|Projects|VC++ Directories and under the "Show Directories For:" dropbox select "Include Files", and click the "New Directory Icon" and add the [SDLROOT]\include directory (ex. If you installed to c:\SDL-1.2.5\ add c:\SDL-1.2.5\include). Proceed to change the dropbox selection to "Library Files" and add [SDLROOT]\lib.</FONT></STRONG> </P> <P> The "include directory" I am referring to is the <CODE>include</CODE> folder within the main SDL directory (the one that this HTML file located within). </P> <P> Now we're going to use the files that we had created earlier in the Build SDL step. </P> <P> Copy the following files into your Project directory: </P> <ul> <li> SDL.dll</li> </ul> <P> Add the following files to your project (It is not necessary to copy them to your project directory): </P> <ul> <li> SDL.lib </li> <li> SDLmain.lib</li> </ul> <P> (To add them to your project, right click on your project, and select "Add files to project") </P> <P><STRONG><FONT color="#009900">Instead of adding the files to your project it is more desireable to add them to the linker options: Project|Properties|Linker|Command Line and type the names of the libraries to link with in the "Additional Options:" box. Note: This must be done for each build configuration (eg. Release,Debug).</FONT></STRONG></P> <H3> SDL 101, First Day of Class </H3> <P> Now create the basic body of your project. The body of your program should take the following form: <CODE> <PRE> #include "SDL.h" int main( int argc, char* argv[] ) { // Body of the program goes here. return 0; } </PRE> </CODE> <P></P> <H3> That's it! </H3> <P> I hope that this document has helped you get through the most difficult part of using the SDL: installing it. Suggestions for improvements to this document should be sent to the writers of this document. </P> <P> Thanks to Paulus Esterhazy (pesterhazy@gmx.net), for the work on VC++ port. </P> <P> This document was originally called "VisualC.txt", and was written by <A HREF="mailto:slouken@libsdl.org"> Sam Lantinga</A>. </P> <P> Later, it was converted to HTML and expanded into the document that you see today by <A HREF="mailto:snowlion@sprynet.com">Lion Kimbro</A>. </P> <P>Minor Fixes and Visual C++ 7 Information (In Green) was added by <A HREF="mailto:james@conceptofzero.net">James Turk</A> </P> </BODY> </HTML>