1 /*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2021 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
WIN_CreateWindowFramebuffer(_THIS,SDL_Window * window,Uint32 * format,void ** pixels,int * pitch)27 int WIN_CreateWindowFramebuffer(_THIS, SDL_Window * window, Uint32 * format, void ** pixels, int *pitch)
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
59 *format = SDL_PIXELFORMAT_UNKNOWN;
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 }
68 if (*format == SDL_PIXELFORMAT_UNKNOWN)
69 {
70 /* We'll use RGB format for now */
71 *format = SDL_PIXELFORMAT_RGB888;
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
WIN_UpdateWindowFramebuffer(_THIS,SDL_Window * window,const SDL_Rect * rects,int numrects)99 int WIN_UpdateWindowFramebuffer(_THIS, SDL_Window * window, const SDL_Rect * rects, int numrects)
100 {
101 SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
102 int i;
103
104 for (i = 0; i < numrects; ++i) {
105 BitBlt(data->hdc, rects[i].x, rects[i].y, rects[i].w, rects[i].h,
106 data->mdc, rects[i].x, rects[i].y, SRCCOPY);
107 }
108 return 0;
109 }
110
WIN_DestroyWindowFramebuffer(_THIS,SDL_Window * window)111 void WIN_DestroyWindowFramebuffer(_THIS, SDL_Window * window)
112 {
113 SDL_WindowData *data = (SDL_WindowData *) window->driverdata;
114
115 if (!data) {
116 /* The window wasn't fully initialized */
117 return;
118 }
119
120 if (data->mdc) {
121 DeleteDC(data->mdc);
122 data->mdc = NULL;
123 }
124 if (data->hbm) {
125 DeleteObject(data->hbm);
126 data->hbm = NULL;
127 }
128 }
129
130 #endif /* SDL_VIDEO_DRIVER_WINDOWS */
131
132 /* vi: set ts=4 sw=4 expandtab: */
133