[SDL] Blitting SDL_Surface to SDL_Overlay...

[Sheshadri Mantha]

oops! I'm using sdl-1.2.11.

Sheshadri Mantha wrote:
> hi;
> i've got a video player that renders yuv using SDL_Overlay.  my video 
> is typically PAL so 720x576.  the video images are rendered using 
> SDL_DisplayYUVOverlay, where the rectangle is derived from aspect 
> ratio that is in the incoming video stream (lets say its 4:3).  Then 
> the resulting rect used in SDL_DisplayYUVOverlay turns out to be {0, 
> 18, 720, 540}.  This is fine...  BTW: the code is modeled after 
> FFmpeg's sample ffplay.c.
>
> problem arises with graphics that i wish to display on top of the 
> video...  such graphic is collected in an SDL_Surface.  Typically 
> these graphics are in the {0, 0, 720, 576} "coordinate space".
>
> currently i have a homegrown fn which blits the graphic SDL_Surface, 
> YUV video image.
>
> PROBLEM is that since the rect for SDL_DisplayYUVOverlay is that which 
> is result of video aspect ratio, portions of the graphic don't get shown.
>
> Calling SDL_DisplayYUVOverlay 2x causes terrible flicker (as can be 
> deduced)
> Doing an UpdateRect of the SDL_Surface shows nothing ('cause i imagine 
> that the subsequent DisplayYUVOverlay scrubs the graphics)
>
> I've also tried converting the video image to RGB, blitting graphic 
> and video RGB... its ok but in full screen the update is terrible 
> (extremely slow!)
>
> Questions:
> - Any idea how i can effectively blit a SDL_Surface onto an 
> SDL_Overlay so that the video appears with proper aspect ratio and 
> graphic appears in its rectangle ?
> - how can i *hack* (even platform dependent method/access to 
> SDL_Overlay private data) to effectively get a SDL_Surface to 
> SDL_Surface blit ?  i tried this by adding a SDL_GetDisplayYUV_SW - my 
> env only loads the sw overlays - to return the SDL_Surface in 
> overlay's private data, and then do a blit but this crashes - Yes i 
> realize i ought not to be accessing these structures - but i've gotta 
> but this release out and need a quick fix. or a fix.
> - why isn't there a "take this graphic and lay it on top of the YUV 
> image in the overlay" method ? Or is there?
>
> Any help quick/otherwise is **GREATLY** appreciated.  Till now my 
> customers (internal though they are) are very, very disappointed in 
> this...
>
> Kindest regards,
> S-