I am using SDL and this function cause my program to use all of my memory

Question

I am a beginner to C++ and this function cause the memory of my program to continuously raise.

It's called in a while loop and it never stop.

void text_box()
{
    SDL_Surface *MESSAGE1 = TTF_RenderText_Solid( font,  "Ligne #1" , noir );                     
    SDL_Surface *MESSAGE2 = TTF_RenderText_Solid( font,  "Ligne #2" , noir );
    SDL_Surface *MESSAGE3 = TTF_RenderText_Solid( font,  "Ligne #3" , noir );
    SDL_Surface *MESSAGE4 = TTF_RenderText_Solid( font,  "Ligne #4" , noir );
    SDL_Surface *MESSAGE5 = TTF_RenderText_Solid( font,  "Ligne #5" , noir );
    SDL_Surface *MESSAGE6 = TTF_RenderText_Solid( font,  "Ligne #6" , noir );
    SDL_Surface *MESSAGE7 = TTF_RenderText_Solid( font,  "Ligne #7" , noir );
    SDL_Surface *MESSAGE8 = TTF_RenderText_Solid( font,  "Ligne #8" , noir );
    SDL_Surface *MESSAGE9 = TTF_RenderText_Solid( font,  "Ligne #9" , noir );
    SDL_Surface *MESSAGE10 = TTF_RenderText_Solid( font,  "Ligne #10" , noir );
    apply_surface( 0, 403, MESSAGE1, SCREEN );
    apply_surface( 0, 412, MESSAGE2, SCREEN );
    apply_surface( 0, 421, MESSAGE3, SCREEN );
    apply_surface( 0, 429, MESSAGE4, SCREEN );
    apply_surface( 0, 438, MESSAGE5, SCREEN );
    apply_surface( 0, 447, MESSAGE6, SCREEN );
    apply_surface( 0, 456, MESSAGE7, SCREEN );
    apply_surface( 0, 465, MESSAGE8, SCREEN );
    apply_surface( 0, 474, MESSAGE9, SCREEN );
    apply_surface( 0, 483, MESSAGE10, SCREEN );
}

It raise in a linear way until there is no more memory left.

Joe Z · Answer 1 · 2013-12-15T19:31:16.430

2

TTF_RenderText_Solid returns a pointer to a new SDL_Surface.

You need to free this surface when you're done with it.

In this particular case, since your text never changes, and I'm guessing font and noir are fixed, you could initialize MESSAGE1 through MESSAGE10 once, and reuse them, as suggested by Bartlomiej Lewandowski below. Then you only need to free the surfaces if you reach a part of your program where they're no longer needed for display.

edited Dec 15 '13 at 19:31

answered Dec 15 '13 at 19:20

Joe Z

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or even better, make it once and pass it as a parameter – Bartlomiej Lewandowski Dec 15 '13 at 19:20
@BartlomiejLewandowski : And what parameter would that be? I don't see an `SDL_Surface *` parameter in the API. – Joe Z Dec 15 '13 at 19:22
I mean, pass it along to his `text_box()` function. The text does not change, so there is no need to generate a new surface in each loop. – Bartlomiej Lewandowski Dec 15 '13 at 19:27
@BartlomiejLewandowski : Ah, good point. Allocate the surfaces once, and destroy them only when there's no longer any reason to display them. – Joe Z Dec 15 '13 at 19:28

I am using SDL and this function cause my program to use all of my memory

1 Answers1