Creating a nested for loop clipping function

Question

My old C++ code reads a spritesheet (rows = different buttons, cols = different button states) one row at a time using for loops and divides them into individual sprite clips. All the sprites are the same size. Works fine.

Now, I want to put the elements of the clipping for loops into a struct so that I can write a single clipping function to iterate through every graphic on a given spritesheet. Running into a few problems getting everything to work. Something changed with the enums when I put them in the struct, and I think I screwed up the nested for loop.

Old Code

const int LONGBUTTON_HEIGHT = 128;
const int LONGBUTTON_WIDTH = 256;

enum CreateButtonState { CREATE_DEFAULT, CREATE_HOVER, CREATE_PRESSED, CREATE_TOTAL };
enum CreditsButtonState { CREDITS_DEFAULT, CREDITS_HOVER, CREDITS_PRESSED, CREDITS_TOTAL };
enum MenuButtonState { MENU_DEFAULT, MENU_HOVER, MENU_PRESSED, MENU_TOTAL };

main
{

//Load long button spritesheet texture
SDL_Texture* longbutton_image = loadTexture("longbuttonSpriteSheet.png", renderer);

//Long Buttons
//Create Button Setup
SDL_Rect create_clips[CreateButtonState::CREATE_TOTAL];
for (int i = 0; i < CreateButtonState::CREATE_TOTAL; i++)
{
    create_clips[i].x = i * LONGBUTTON_WIDTH;
    create_clips[i].y = 0;
    create_clips[i].w = LONGBUTTON_WIDTH;
    create_clips[i].h = LONGBUTTON_HEIGHT;
}
int useCreate_Clip = CREATE_DEFAULT;

// Credits Button Setup
SDL_Rect credits_clips[CreditsButtonState::CREDITS_TOTAL];
for (int i = 0; i < CreditsButtonState::CREDITS_TOTAL; i++)
{
    credits_clips[i].x = i * LONGBUTTON_WIDTH;
    credits_clips[i].y = 1 * LONGBUTTON_HEIGHT;
    credits_clips[i].w = LONGBUTTON_WIDTH;
    credits_clips[i].h = LONGBUTTON_HEIGHT;
}
int useCredits_Clip = CREDITS_DEFAULT;

//Menu Button Setup
SDL_Rect menu_clips[MenuButtonState::MENU_TOTAL];
for (int i = 0; i < MenuButtonState::MENU_TOTAL; i++)
{
    menu_clips[i].x = i * LONGBUTTON_WIDTH;
    menu_clips[i].y = 2 * LONGBUTTON_HEIGHT;
    menu_clips[i].w = LONGBUTTON_WIDTH;
    menu_clips[i].h = LONGBUTTON_HEIGHT;
}
int useMenu_Clip = MENU_DEFAULT;

return 0;

}

New Code

int originalspriteH = 128;
int originalspriteW = 256;
int spritesheetcols = 2;

    struct Graphic
    {
    typedef enum buttonstate {DEFAULT, HOVER, PRESSED, TOTAL};
    SDL_Rect clip;
    int useClip;
    };

    void clipSprites(int spritesheetcols, int originalspriteH, int originalspriteW, [Graphic &graphic])
    {
    for (int j =0; j < spritesheetcols; j++)
    {
        graphic.clip[graphic.buttonstate::TOTAL];
    }
        for (int i = 0, i < graphic.buttonstate::TOTAL; i++)
        {
            graphic.clip[i].x = i * originalspriteW;
            graphic.clip[i].y = j * originalspriteH; 
            graphic.clip[i].h = originalspriteW;
            graphic.clip[i].w =  originalspriteH; 
        }
        graphic.useClip = DEFAULT;
    }

main
{

clipSprites(2, 128, 256, [create, credits, menu])   

return 0;
}

Make small changes at a time. Compile , test and fix. Repeat. — Phil1970, Jul 21 '21 at 00:57
This is a small change. The entire code does compile. This is just the tiny snippet I want to modify and the parts it needs to work. — Jeffrey, Jul 21 '21 at 01:46
Then you may try to fix the compiler error, a modern compiler will give you many hints to fix thme. — prehistoricpenguin, Jul 21 '21 at 02:53
There are numerous errors in the "new" code. Perhaps you meant to declare `SDL_RECT clip[buttonstate::TOTAL];` in `struct Graphic`? And you don't have nested loops in `clipSprites`; you have two loops that run sequentially (the first does nothing). — 1201ProgramAlarm, Jul 21 '21 at 02:56

Creating a nested for loop clipping function

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