sdl game

i make a sdl c++ game i now i have this problem.
the screen resolution in fullscreen mode is 1920x1080 but if i play it on another computer screen with the screen resolution 960x540 the game crashes because of the pixel resolution.

how can i make the screen smaler without making every picture again and place it on other position.
only making the screen surface smaler but to see the same as in 1920x1080 only smaler

sorry for bad english(i´m from germany):)

i dont think that this solves my problem
perhaps there an option to create a "second screen" where i can make the whole blitting etc. with the original size(1920x1080)
and then show the second screen (resized with the correct resolution) on the first shown screen(with the computer screen resolution "960x540","1600x800" and so on)

thanks for answer!!!!!!!!:):mad::(:ausheck::confused::o

whats an offline framebuffer
sorry for the bad english

do you know how to define a buffer/surface because that i dont have to go throught his whole code

i found it for other who have problems with it heres the code
screen = SDL_CreateRGBSurface(SDL_SWSURFACE, 1920, 1080, format->BitsPerPixel,
format->Rmask, format->Gmask, format->Bmask, format->Amask);
create a screan like that and make all blitting on it!!!
after all blittings blit the"screen" on the real screen(the one who is shown)and shrink the screen in a funktion
apply_surface(0,0,shrinkSurface(screen, 2,2),screen_shown);

perhaps do you know a good shrinking function
except sdl gfx (there is only possible to make the surface half of real or the 1/3 or 1/4 and so on)

there is nothing to resize an image

does anyone know something
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