/*+
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    SDL - Simple DirectMedia Layer+
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    Copyright (C) 1997-2006 Sam Lantinga+
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+
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    This library is free software; you can redistribute it and/or+
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    modify it under the terms of the GNU Lesser General Public+
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    License as published by the Free Software Foundation; either+
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    version 2.1 of the License, or (at your option) any later version.+
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+
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    This library is distributed in the hope that it will be useful,+
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    but WITHOUT ANY WARRANTY; without even the implied warranty of+
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    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU+
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    Lesser General Public License for more details.+
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+
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    You should have received a copy of the GNU Lesser General Public+
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    License along with this library; if not, write to the Free Software+
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    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA+
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+
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    Sam Lantinga+
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    slouken@libsdl.org+
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*/+
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#include "SDL_config.h"+
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+
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/* This is the implementation of the YUV video surface support */+
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+
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#include "SDL_video.h"+
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#include "SDL_sysvideo.h"+
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#include "SDL_yuvfuncs.h"+
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#include "SDL_yuv_sw_c.h"+
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+
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+
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SDL_Overlay *SDL_CreateYUVOverlay(int w, int h, Uint32 format,+
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                                  SDL_Surface *display)+
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{+
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	SDL_VideoDevice *video = current_video;+
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	SDL_VideoDevice *this  = current_video;+
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	const char *yuv_hwaccel;+
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	SDL_Overlay *overlay;+
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+
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	if ( (display->flags & SDL_OPENGL) == SDL_OPENGL ) {+
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		SDL_SetError("YUV overlays are not supported in OpenGL mode");+
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		return NULL;+
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	}+
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+
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	/* Display directly on video surface, if possible */+
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	if ( SDL_getenv("SDL_VIDEO_YUV_DIRECT") ) {+
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		if ( (display == SDL_PublicSurface) &&+
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		     ((SDL_VideoSurface->format->BytesPerPixel == 2) ||+
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		      (SDL_VideoSurface->format->BytesPerPixel == 4)) ) {+
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			display = SDL_VideoSurface;+
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		}+
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	}+
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	overlay = NULL;+
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        yuv_hwaccel = SDL_getenv("SDL_VIDEO_YUV_HWACCEL");+
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	if ( ((display == SDL_VideoSurface) && video->CreateYUVOverlay) &&+
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	     (!yuv_hwaccel || (SDL_atoi(yuv_hwaccel) > 0)) ) {+
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		overlay = video->CreateYUVOverlay(this, w, h, format, display);+
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	}+
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	/* If hardware YUV overlay failed ... */+
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	if ( overlay == NULL ) {+
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		overlay = SDL_CreateYUV_SW(this, w, h, format, display);+
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	}+
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	return overlay;+
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}+
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+
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int SDL_LockYUVOverlay(SDL_Overlay *overlay)+
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{+
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	return overlay->hwfuncs->Lock(current_video, overlay);+
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}+
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+
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void SDL_UnlockYUVOverlay(SDL_Overlay *overlay)+
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{+
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	overlay->hwfuncs->Unlock(current_video, overlay);+
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}+
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+
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int SDL_DisplayYUVOverlay(SDL_Overlay *overlay, SDL_Rect *dstrect)+
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{+
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	SDL_Rect src, dst;+
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	int srcx, srcy, srcw, srch;+
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	int dstx, dsty, dstw, dsth;+
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+
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	/* Clip the rectangle to the screen area */+
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	srcx = 0;+
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	srcy = 0;+
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	srcw = overlay->w;+
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	srch = overlay->h;+
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	dstx = dstrect->x;+
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	dsty = dstrect->y;+
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	dstw = dstrect->w;+
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	dsth = dstrect->h;+
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	if ( dstx < 0 ) {+
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		srcw += (dstx * overlay->w) / dstrect->w;+
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		dstw += dstx;+
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		srcx -= (dstx * overlay->w) / dstrect->w;+
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		dstx = 0;+
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	}+
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	if ( (dstx+dstw) > current_video->screen->w ) {+
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		int extra = (dstx+dstw - current_video->screen->w);+
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		srcw -= (extra * overlay->w) / dstrect->w;+
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		dstw -= extra;+
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	}+
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	if ( dsty < 0 ) {+
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		srch += (dsty * overlay->h) / dstrect->h;+
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		dsth += dsty;+
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		srcy -= (dsty * overlay->h) / dstrect->h;+
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		dsty = 0;+
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	}+
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	if ( (dsty+dsth) > current_video->screen->h ) {+
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		int extra = (dsty+dsth - current_video->screen->h);+
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		srch -= (extra * overlay->h) / dstrect->h;+
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		dsth -= extra;+
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	}+
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	if ( srcw <= 0 || srch <= 0 ||+
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	     srch <= 0 || dsth <= 0 ) {+
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		return 0;+
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	}+
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	/* Ugh, I can't wait for SDL_Rect to be int values */+
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	src.x = srcx;+
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	src.y = srcy;+
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	src.w = srcw;+
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	src.h = srch;+
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	dst.x = dstx;+
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	dst.y = dsty;+
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	dst.w = dstw;+
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	dst.h = dsth;+
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	return overlay->hwfuncs->Display(current_video, overlay, &src, &dst);+
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}+
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+
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void SDL_FreeYUVOverlay(SDL_Overlay *overlay)+
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{+
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	if ( overlay ) {+
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		if ( overlay->hwfuncs ) {+
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			overlay->hwfuncs->FreeHW(current_video, overlay);+
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		}+
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		SDL_free(overlay);+
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	}+
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}+
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