SDL  2.0
SDL_windowsframebuffer.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "../../SDL_internal.h"
22 
23 #if SDL_VIDEO_DRIVER_WINDOWS
24 
25 #include "SDL_windowsvideo.h"
26 
28 {
30  size_t size;
31  LPBITMAPINFO info;
32  HBITMAP hbm;
33 
34  /* Free the old framebuffer surface */
35  if (data->mdc) {
36  DeleteDC(data->mdc);
37  }
38  if (data->hbm) {
39  DeleteObject(data->hbm);
40  }
41 
42  /* Find out the format of the screen */
43  size = sizeof(BITMAPINFOHEADER) + 256 * sizeof (RGBQUAD);
44  info = (LPBITMAPINFO)SDL_stack_alloc(Uint8, size);
45  if (!info) {
46  return SDL_OutOfMemory();
47  }
48 
49  SDL_memset(info, 0, size);
50  info->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
51 
52  /* The second call to GetDIBits() fills in the bitfields */
53  hbm = CreateCompatibleBitmap(data->hdc, 1, 1);
54  GetDIBits(data->hdc, hbm, 0, 0, NULL, info, DIB_RGB_COLORS);
55  GetDIBits(data->hdc, hbm, 0, 0, NULL, info, DIB_RGB_COLORS);
56  DeleteObject(hbm);
57 
58  *format = SDL_PIXELFORMAT_UNKNOWN;
59  if (info->bmiHeader.biCompression == BI_BITFIELDS) {
60  int bpp;
61  Uint32 *masks;
62 
63  bpp = info->bmiHeader.biPlanes * info->bmiHeader.biBitCount;
64  masks = (Uint32*)((Uint8*)info + info->bmiHeader.biSize);
65  *format = SDL_MasksToPixelFormatEnum(bpp, masks[0], masks[1], masks[2], 0);
66  }
67  if (*format == SDL_PIXELFORMAT_UNKNOWN)
68  {
69  /* We'll use RGB format for now */
70  *format = SDL_PIXELFORMAT_RGB888;
71 
72  /* Create a new one */
73  SDL_memset(info, 0, size);
74  info->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
75  info->bmiHeader.biPlanes = 1;
76  info->bmiHeader.biBitCount = 32;
77  info->bmiHeader.biCompression = BI_RGB;
78  }
79 
80  /* Fill in the size information */
81  *pitch = (((window->w * SDL_BYTESPERPIXEL(*format)) + 3) & ~3);
82  info->bmiHeader.biWidth = window->w;
83  info->bmiHeader.biHeight = -window->h; /* negative for topdown bitmap */
84  info->bmiHeader.biSizeImage = window->h * (*pitch);
85 
86  data->mdc = CreateCompatibleDC(data->hdc);
87  data->hbm = CreateDIBSection(data->hdc, info, DIB_RGB_COLORS, pixels, NULL, 0);
88  SDL_stack_free(info);
89 
90  if (!data->hbm) {
91  return WIN_SetError("Unable to create DIB");
92  }
93  SelectObject(data->mdc, data->hbm);
94 
95  return 0;
96 }
97 
98 int WIN_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
99 {
100  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
101 
102  BitBlt(data->hdc, 0, 0, window->w, window->h, data->mdc, 0, 0, SRCCOPY);
103  return 0;
104 }
105 
107 {
108  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
109 
110  if (!data) {
111  /* The window wasn't fully initialized */
112  return;
113  }
114 
115  if (data->mdc) {
116  DeleteDC(data->mdc);
117  data->mdc = NULL;
118  }
119  if (data->hbm) {
120  DeleteObject(data->hbm);
121  data->hbm = NULL;
122  }
123 }
124 
125 #endif /* SDL_VIDEO_DRIVER_WINDOWS */
126 
127 /* vi: set ts=4 sw=4 expandtab: */
#define BI_RGB
Definition: SDL_bmp.c:45
#define SDL_MasksToPixelFormatEnum
#define SDL_BYTESPERPIXEL(X)
Definition: SDL_pixels.h:128
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
uint32_t Uint32
Definition: SDL_stdinc.h:181
int WIN_CreateWindowFramebuffer(_THIS, SDL_Window *window, Uint32 *format, void **pixels, int *pitch)
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
void WIN_DestroyWindowFramebuffer(_THIS, SDL_Window *window)
#define _THIS
uint8_t Uint8
Definition: SDL_stdinc.h:157
#define SDL_stack_alloc(type, count)
Definition: SDL_stdinc.h:354
GLint GLint GLsizei GLsizei GLsizei GLint GLenum GLenum const GLvoid * pixels
Definition: SDL_opengl.h:1572
GLsizeiptr size
#define BI_BITFIELDS
Definition: SDL_bmp.c:48
#define NULL
Definition: begin_code.h:164
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
int WIN_SetError(const char *prefix)
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
The type used to identify a window.
Definition: SDL_sysvideo.h:73
void * driverdata
Definition: SDL_sysvideo.h:111
EGLSurface EGLint * rects
Definition: eglext.h:282
#define SDL_stack_free(data)
Definition: SDL_stdinc.h:355
#define SDL_memset
A rectangle, with the origin at the upper left.
Definition: SDL_rect.h:64
int WIN_UpdateWindowFramebuffer(_THIS, SDL_Window *window, const SDL_Rect *rects, int numrects)