view src/video/gapi/SDL_gapivideo.h @ 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 86d0d01290ea
children c9b51268668f
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2004 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id$";
#endif

#ifndef _SDL_gapivideo_h
#define _SDL_gapivideo_h

#include "SDL_mouse.h"
#include "SDL_sysvideo.h"
#include "SDL_mutex.h"

/* From gx.h, since it's not really C compliant */

struct GXDisplayProperties {
    DWORD cxWidth;
    DWORD cyHeight;         // notice lack of 'th' in the word height.
    long cbxPitch;          // number of bytes to move right one x pixel - can be negative.
    long cbyPitch;          // number of bytes to move down one y pixel - can be negative.
    long cBPP;              // # of bits in each pixel
    DWORD ffFormat;         // format flags.
};

struct GXKeyList {
    short vkUp;             // key for up
    POINT ptUp;             // x,y position of key/button.  Not on screen but in screen coordinates.
    short vkDown;
    POINT ptDown;
    short vkLeft;
    POINT ptLeft;
    short vkRight;
    POINT ptRight;
    short vkA;
    POINT ptA;
    short vkB;
    POINT ptB;
    short vkC;
    POINT ptC;
    short vkStart;
    POINT ptStart;
};

typedef int   (*PFNGXOpenDisplay)(HWND hWnd, DWORD dwFlags);
typedef int   (*PFNGXCloseDisplay)();
typedef void* (*PFNGXBeginDraw)();
typedef int   (*PFNGXEndDraw)();
typedef int   (*PFNGXOpenInput)();
typedef int   (*PFNGXCloseInput)();
typedef struct GXDisplayProperties (*PFNGXGetDisplayProperties)();
typedef struct GXKeyList (*PFNGXGetDefaultKeys)(int iOptions);
typedef int   (*PFNGXSuspend)();
typedef int   (*PFNGXResume)();
typedef int   (*PFNGXSetViewport)( DWORD dwTop, DWORD dwHeight, DWORD dwReserved1, DWORD dwReserved2 );
typedef BOOL  (*PFNGXIsDisplayDRAMBuffer)();

struct GapiFunc
{
    PFNGXOpenDisplay          GXOpenDisplay;
    PFNGXCloseDisplay         GXCloseDisplay;
    PFNGXBeginDraw            GXBeginDraw;
    PFNGXEndDraw              GXEndDraw;
    PFNGXOpenInput            GXOpenInput;
    PFNGXCloseInput           GXCloseInput;
    PFNGXGetDisplayProperties GXGetDisplayProperties;
    PFNGXGetDefaultKeys       GXGetDefaultKeys;
    PFNGXSuspend              GXSuspend;
    PFNGXResume               GXResume;
    PFNGXSetViewport          GXSetViewport;
    PFNGXIsDisplayDRAMBuffer  GXIsDisplayDRAMBuffer;
};

#define kfLandscape	0x8			// Screen is rotated 270 degrees
#define kfPalette	0x10		// Pixel values are indexes into a palette
#define kfDirect	0x20		// Pixel values contain actual level information
#define kfDirect555	0x40		// 5 bits each for red, green and blue values in a pixel.
#define kfDirect565	0x80		// 5 red bits, 6 green bits and 5 blue bits per pixel
#define kfDirect888	0x100		// 8 bits each for red, green and blue values in a pixel.
#define kfDirect444	0x200		// 4 red, 4 green, 4 blue
#define kfDirectInverted 0x400

#define GX_FULLSCREEN	0x01		// for OpenDisplay() 
#define GX_NORMALKEYS   0x02
#define GX_LANDSCAPEKEYS        0x03

typedef enum
{
	SDL_ORIENTATION_UP,
	SDL_ORIENTATION_DOWN,
	SDL_ORIENTATION_LEFT,
	SDL_ORIENTATION_RIGHT
} SDL_ScreenOrientation;

/* GAPI video mode */
typedef enum {
	GAPI_NONE = 0,
	GAPI_DIRECT_565,
	GAPI_DIRECT_555,
	GAPI_MONO,
	GAPI_PALETTE
} GAPIVideoMode; 

/* Hidden "this" pointer for the video functions */
#define _THIS	SDL_VideoDevice *this

typedef unsigned short PIXEL;

/* Private display data 
   begin with DIB private structure to allow DIB events code sharing
*/
struct SDL_PrivateVideoData {
    HBITMAP screen_bmp;
    HPALETTE screen_pal;

#define NUM_MODELISTS	4		/* 8, 16, 24, and 32 bits-per-pixel */
    int SDL_nummodes[NUM_MODELISTS];
    SDL_Rect **SDL_modelist[NUM_MODELISTS];
	enum SDL_ScreenOrientation userOrientation;
	int invert;
	char hiresFix; // using hires mode without defining hires resource
// --------------
    int w, h;
	enum SDL_ScreenOrientation gapiOrientation;

    void *buffer; // may be 8, 16, 24, 32 bpp
	PIXEL *videoMem;
	BOOL needUpdate;
	struct GXKeyList keyList;
	struct GapiFunc gxFunc;
	struct GXDisplayProperties gxProperties;
	enum GAPIVideoMode videoMode;
	int colorscale;
	int dstLineStep;  // in bytes
	int dstPixelStep; // in bytes
	int startOffset; // in bytes
	int useVga;
};


#define gapiBuffer this->hidden->buffer
#define gapi this->hidden

#endif /* _SDL_gapivideo_h */