No matching function for call to 'SDL_UpperBlit'

Question

I'm relatively new to c++, so despite my experience in other c languages this may just be a simple mistake. Here's my code:

#include <iostream>
#include <SDL2/SDL.h>

SDL_Window *window;
SDL_Surface *windowSurface;
SDL_Surface *image[3];
SDL_Surface *currentImage;
int close();
SDL_Rect gRect(int, int, int, int); //for method described below

int main(int argc, char *argv[]){

    SDL_Init(SDL_INIT_VIDEO);
    window = SDL_CreateWindow("Test", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 500, 500, SDL_WINDOW_SHOWN);
    windowSurface = SDL_GetWindowSurface(window);
    image[0] = SDL_LoadBMP("filepath/img.bmp");
    image[1] = SDL_LoadBMP("filepath/img2.bmp");
    image[2] = SDL_LoadBMP("filepath/img3.bmp");
    currentImage = image[0];


    bool done = false;
    while(!done){
        SDL_Rect rec;
        rec.x = 100;
        rec.y = 100;
        rec.h = 100;
        rec.w = 100;
        SDL_BlitSurface(currentImage, NULL, windowSurface, rec);
        SDL_UpdateWindowSurface(window);
    }
    return close();
}
int close(){
    for(int i = 0; i < 3; i++){
        SDL_FreeSurface(image[i]);
        image[i] = nullptr;
    }
    currentImage = nullptr;
    window = nullptr;
    SDL_DestroyWindow(window);
    SDL_Quit();
    return 0;
}

Upon running this program I receive the error "No matching function for call to "SDL_UpperBlit"". Apparently this has been replaced with SDL_BlitSurface, which I am using in my program.

This error does not appear if I replace "rec" in the function call with "NULL", and my program compiles like normal, with the image filling the screen.

I tried using a function to create an SDL_Rect like so:

SDL_Rect gRect(int x, int y, int w, int h){
    SDL_Rect ret;
    ret.h = h;
    ret.w = w;
    ret.x = x;
    ret.y = y;
    return ret;
}

and changing the SDL_BlitSurface call to

SDL_BlitSurface(currentImage, NULL, windowSurface, gRect(100, 100, 100, 100));

This does not resolve the issue and the same error appears. If I could get any help with this it would be greatly appreciated! Thanks!

(Optional) PS: I also would appreciate some help with putting the "image[0]", "image[1]", and "image[2]" declarations in a for loop. I tried it but had some issues with types and concatenation so if anyone knows how I could do this let me know.

Answer 1

SDL_BlitSurface function declaration is

int SDL_BlitSurface(SDL_Surface*    src,
                    const SDL_Rect* srcrect,
                    SDL_Surface*    dst,
                    SDL_Rect*       dstrect)

Your code fragment

    SDL_Rect rec;
    rec.x = 100;
    rec.y = 100;
    rec.h = 100;
    rec.w = 100;
    SDL_BlitSurface(currentImage, NULL, windowSurface, rec);

passes rec as last argument, which have type SDL_Rect, but SDL_Rect* is expected. It should be e.g. SDL_BlitSurface(currentImage, NULL, windowSurface, &rec);

I would also advice against using close as function name as it is known to cause problems (not as much true for C++ as it have name mangling, but still).