Atlas - SDL_windowsframebuffer.c
Home / ext / SDL2 / src / video / windows
Lines: 1 | Size: 4063 bytes
[Download] [Show on GitHub] [Search similar files] [Raw] [Raw (proxy)] 
[FILE BEGIN]
1/*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 Sam Lantinga <[email protected]>
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
27int WIN_CreateWindowFramebuffer(_THIS, SDL_Window * window, Uint32 * format, void ** pixels, int *pitch)
28{
29    SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
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
98int 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
106void WIN_DestroyWindowFramebuffer(_THIS, SDL_Window * window)
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: */
128
[FILE END]
(C) 2025 0x4248
(C) 2025 4248 Media and 4248 Systems, All part of 0x4248
See LICENCE files for more information. Not all files are by 0x4248 always check Licencing.