SDL  2.0
SDL_windowsframebuffer.c
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2019 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 {
29  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
30  SDL_bool isstack;
31  size_t size;
32  LPBITMAPINFO info;
33  HBITMAP hbm;
34 
35  /* Free the old framebuffer surface */
36  if (data->mdc) {
37  DeleteDC(data->mdc);
38  }
39  if (data->hbm) {
40  DeleteObject(data->hbm);
41  }
42 
43  /* Find out the format of the screen */
44  size = sizeof(BITMAPINFOHEADER) + 256 * sizeof (RGBQUAD);
45  info = (LPBITMAPINFO)SDL_small_alloc(Uint8, size, &isstack);
46  if (!info) {
47  return SDL_OutOfMemory();
48  }
49 
50  SDL_memset(info, 0, size);
51  info->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
52 
53  /* The second call to GetDIBits() fills in the bitfields */
54  hbm = CreateCompatibleBitmap(data->hdc, 1, 1);
55  GetDIBits(data->hdc, hbm, 0, 0, NULL, info, DIB_RGB_COLORS);
56  GetDIBits(data->hdc, hbm, 0, 0, NULL, info, DIB_RGB_COLORS);
57  DeleteObject(hbm);
58 
60  if (info->bmiHeader.biCompression == BI_BITFIELDS) {
61  int bpp;
62  Uint32 *masks;
63 
64  bpp = info->bmiHeader.biPlanes * info->bmiHeader.biBitCount;
65  masks = (Uint32*)((Uint8*)info + info->bmiHeader.biSize);
66  *format = SDL_MasksToPixelFormatEnum(bpp, masks[0], masks[1], masks[2], 0);
67  }
69  {
70  /* We'll use RGB format for now */
72 
73  /* Create a new one */
74  SDL_memset(info, 0, size);
75  info->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
76  info->bmiHeader.biPlanes = 1;
77  info->bmiHeader.biBitCount = 32;
78  info->bmiHeader.biCompression = BI_RGB;
79  }
80 
81  /* Fill in the size information */
82  *pitch = (((window->w * SDL_BYTESPERPIXEL(*format)) + 3) & ~3);
83  info->bmiHeader.biWidth = window->w;
84  info->bmiHeader.biHeight = -window->h; /* negative for topdown bitmap */
85  info->bmiHeader.biSizeImage = window->h * (*pitch);
86 
87  data->mdc = CreateCompatibleDC(data->hdc);
88  data->hbm = CreateDIBSection(data->hdc, info, DIB_RGB_COLORS, pixels, NULL, 0);
89  SDL_small_free(info, isstack);
90 
91  if (!data->hbm) {
92  return WIN_SetError("Unable to create DIB");
93  }
94  SelectObject(data->mdc, data->hbm);
95 
96  return 0;
97 }
98 
99 int WIN_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
100 {
101  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
102 
103  BitBlt(data->hdc, 0, 0, window->w, window->h, data->mdc, 0, 0, SRCCOPY);
104  return 0;
105 }
106 
108 {
109  SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
110 
111  if (!data) {
112  /* The window wasn't fully initialized */
113  return;
114  }
115 
116  if (data->mdc) {
117  DeleteDC(data->mdc);
118  data->mdc = NULL;
119  }
120  if (data->hbm) {
121  DeleteObject(data->hbm);
122  data->hbm = NULL;
123  }
124 }
125 
126 #endif /* SDL_VIDEO_DRIVER_WINDOWS */
127 
128 /* vi: set ts=4 sw=4 expandtab: */
format
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1572
WIN_UpdateWindowFramebuffer
int WIN_UpdateWindowFramebuffer(_THIS, SDL_Window *window, const SDL_Rect *rects, int numrects)
SDL_memset
#define SDL_memset
Definition: SDL_dynapi_overrides.h:386
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_small_free
#define SDL_small_free(ptr, isstack)
Definition: SDL_internal.h:40
SDL_PIXELFORMAT_RGB888
@ SDL_PIXELFORMAT_RGB888
Definition: SDL_pixels.h:236
NULL
#define NULL
Definition: begin_code.h:167
SDL_WindowData
Definition: SDL_androidwindow.h:38
SDL_MasksToPixelFormatEnum
#define SDL_MasksToPixelFormatEnum
Definition: SDL_dynapi_overrides.h:279
SDL_small_alloc
#define SDL_small_alloc(type, count, pisstack)
Definition: SDL_internal.h:39
data
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1974
SDL_Window
The type used to identify a window.
Definition: SDL_sysvideo.h:73
WIN_DestroyWindowFramebuffer
void WIN_DestroyWindowFramebuffer(_THIS, SDL_Window *window)
SDL_windowsvideo.h
window
EGLSurface EGLNativeWindowType * window
Definition: eglext.h:1025
WIN_CreateWindowFramebuffer
int WIN_CreateWindowFramebuffer(_THIS, SDL_Window *window, Uint32 *format, void **pixels, int *pitch)
_THIS
#define _THIS
Definition: SDL_alsa_audio.h:31
pixels
GLint GLint GLsizei GLsizei GLsizei GLint GLenum GLenum const GLvoid * pixels
Definition: SDL_opengl.h:1572
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
size
GLsizeiptr size
Definition: SDL_opengl_glext.h:537
BI_RGB
#define BI_RGB
Definition: SDL_bmp.c:45
SDL_BYTESPERPIXEL
#define SDL_BYTESPERPIXEL(X)
Definition: SDL_pixels.h:128
WIN_SetError
int WIN_SetError(const char *prefix)
SDL_Rect
A rectangle, with the origin at the upper left (integer).
Definition: SDL_rect.h:77
SDL_PIXELFORMAT_UNKNOWN
@ SDL_PIXELFORMAT_UNKNOWN
Definition: SDL_pixels.h:173
BI_BITFIELDS
#define BI_BITFIELDS
Definition: SDL_bmp.c:48
rects
EGLSurface EGLint * rects
Definition: eglext.h:282
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:161
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179