1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2009 Sam Lantinga
4
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19 Sam Lantinga
20 slouken@libsdl.org
21 */
22 #include "SDL_config.h"
23
24 /* This is the implementation of the YUV video surface support */
25
26 #include "SDL_video.h"
27 #include "SDL_sysvideo.h"
28 #include "SDL_yuvfuncs.h"
29 #include "SDL_yuv_sw_c.h"
30
31
SDL_CreateYUVOverlay(int w,int h,Uint32 format,SDL_Surface * display)32 SDL_Overlay *SDL_CreateYUVOverlay(int w, int h, Uint32 format,
33 SDL_Surface *display)
34 {
35 SDL_VideoDevice *video = current_video;
36 SDL_VideoDevice *this = current_video;
37 const char *yuv_hwaccel;
38 SDL_Overlay *overlay;
39
40 if ( (display->flags & SDL_OPENGL) == SDL_OPENGL ) {
41 SDL_SetError("YUV overlays are not supported in OpenGL mode");
42 return NULL;
43 }
44
45 /* Display directly on video surface, if possible */
46 if ( SDL_getenv("SDL_VIDEO_YUV_DIRECT") ) {
47 if ( (display == SDL_PublicSurface) &&
48 ((SDL_VideoSurface->format->BytesPerPixel == 2) ||
49 (SDL_VideoSurface->format->BytesPerPixel == 4)) ) {
50 display = SDL_VideoSurface;
51 }
52 }
53 overlay = NULL;
54 yuv_hwaccel = SDL_getenv("SDL_VIDEO_YUV_HWACCEL");
55 if ( ((display == SDL_VideoSurface) && video->CreateYUVOverlay) &&
56 (!yuv_hwaccel || (SDL_atoi(yuv_hwaccel) > 0)) ) {
57 overlay = video->CreateYUVOverlay(this, w, h, format, display);
58 }
59 /* If hardware YUV overlay failed ... */
60 if ( overlay == NULL ) {
61 overlay = SDL_CreateYUV_SW(this, w, h, format, display);
62 }
63 return overlay;
64 }
65
SDL_LockYUVOverlay(SDL_Overlay * overlay)66 int SDL_LockYUVOverlay(SDL_Overlay *overlay)
67 {
68 if ( overlay == NULL ) {
69 SDL_SetError("Passed NULL overlay");
70 return -1;
71 }
72 return overlay->hwfuncs->Lock(current_video, overlay);
73 }
74
SDL_UnlockYUVOverlay(SDL_Overlay * overlay)75 void SDL_UnlockYUVOverlay(SDL_Overlay *overlay)
76 {
77 if ( overlay == NULL ) {
78 return;
79 }
80 overlay->hwfuncs->Unlock(current_video, overlay);
81 }
82
SDL_DisplayYUVOverlay(SDL_Overlay * overlay,SDL_Rect * dstrect)83 int SDL_DisplayYUVOverlay(SDL_Overlay *overlay, SDL_Rect *dstrect)
84 {
85 SDL_Rect src, dst;
86 int srcx, srcy, srcw, srch;
87 int dstx, dsty, dstw, dsth;
88
89 if ( overlay == NULL || dstrect == NULL ) {
90 SDL_SetError("Passed NULL overlay or dstrect");
91 return -1;
92 }
93
94 /* Clip the rectangle to the screen area */
95 srcx = 0;
96 srcy = 0;
97 srcw = overlay->w;
98 srch = overlay->h;
99 dstx = dstrect->x;
100 dsty = dstrect->y;
101 dstw = dstrect->w;
102 dsth = dstrect->h;
103 if ( dstx < 0 ) {
104 srcw += (dstx * overlay->w) / dstrect->w;
105 dstw += dstx;
106 srcx -= (dstx * overlay->w) / dstrect->w;
107 dstx = 0;
108 }
109 if ( (dstx+dstw) > current_video->screen->w ) {
110 int extra = (dstx+dstw - current_video->screen->w);
111 srcw -= (extra * overlay->w) / dstrect->w;
112 dstw -= extra;
113 }
114 if ( dsty < 0 ) {
115 srch += (dsty * overlay->h) / dstrect->h;
116 dsth += dsty;
117 srcy -= (dsty * overlay->h) / dstrect->h;
118 dsty = 0;
119 }
120 if ( (dsty+dsth) > current_video->screen->h ) {
121 int extra = (dsty+dsth - current_video->screen->h);
122 srch -= (extra * overlay->h) / dstrect->h;
123 dsth -= extra;
124 }
125 if ( srcw <= 0 || srch <= 0 ||
126 srch <= 0 || dsth <= 0 ) {
127 return 0;
128 }
129 /* Ugh, I can't wait for SDL_Rect to be int values */
130 src.x = srcx;
131 src.y = srcy;
132 src.w = srcw;
133 src.h = srch;
134 dst.x = dstx;
135 dst.y = dsty;
136 dst.w = dstw;
137 dst.h = dsth;
138 return overlay->hwfuncs->Display(current_video, overlay, &src, &dst);
139 }
140
SDL_FreeYUVOverlay(SDL_Overlay * overlay)141 void SDL_FreeYUVOverlay(SDL_Overlay *overlay)
142 {
143 if ( overlay == NULL ) {
144 return;
145 }
146 if ( overlay->hwfuncs ) {
147 overlay->hwfuncs->FreeHW(current_video, overlay);
148 }
149 SDL_free(overlay);
150 }
151