Thread: Inline ASM with SDL Graphics (Not same as C/C++ coding result) ... :(

Hello, thanks for reading my post. I hope you will be able to offer me some help for my problem. I am programming a 2D engine using SDL, and I am having a small amount of trouble getting ASM to work correctly. Here's the code:

Code:

__asm 
{
    // ... A bit of code here
    push 0xffffff         // In SDL this is 'white'
    mov  edx, DWORD PTR dest1    // 'SDL_Rect dest1;'
    push edx
    mov  ecx, DWORD PTR screen   // 'SDL_Surface *screen;'
    push ecx
    call    SDL_FillRect            // Calls 'SDL_FillRect(...)' function
    add   esp, 12

    // ... More code here
}

That code will fill the ENTIRE screen white, while:

Code:

SDL_FillRect(screen, &dest1, 0xffffff);

Will give me what I need. Can you tell me what I am doing wrong?

Thanks in Advance,
Matt U.

Make sure you are pushing the arguments onto the stack in the correct order. Most Windows functions calls, if not all, use the PASCAL calling method where items are pushed left to right, where C pushes right to left. It's either that or vice versa - check your compiler help file.

If you push in the wrong order, you will undoubtedly crash the entire system.

Ok.

Big difference between loading register and loading effective address.

What part of tenn are you from?