CODEWITHSUNDEEP
csdl
user1234975
user1234975

Reputation: 11

defining sdl_rect and sdl_mousebuttondown

I need to define rectangular areas on the sdl window so that when the mouse button is clicked on a particular area some action has to be performed.

I used GetMouseState(x,y) to get the mouse click event. It works wherever the mouse button is clicked. But rather i need to get the mouse x and y and check it with sdl rect x and y to c if whether the rectangle is clicked.

Upvotes: 1

Views: 1895

Answers (3)

pakut2
pakut2

Reputation: 682

There actually is a built-in function for that called SDL_PointInRect. It returns true if clicked and false otherwise

It takes SDL_Point* and SDL_Rect* as arguments

SDL_Point mousePosition;

// Mouse click coords from event handler
mousePosition.x = event.motion.x; 
mousePosition.y = event.motion.y;

if (SDL_PointInRect(&mousePosition, &someSDL_Rect)) {
    // Do something
}

If you look into the header file, this function is very similar to @Alink s answer

Upvotes: 3

Some programmer dude
Some programmer dude

Reputation: 409384

Lets say you create a SDL_Rect structure containing the rectangle you want. When you get the coordinates of a mouse-click it's very simple to compare it with the rectangle coordinates:

/* Function to check if a coordinate (x, y) is inside a rectangle */
int check_click_in_rect(int x, int y, struct SDL_Rect *rect)
{
    /* Check X coordinate is within rectangle range */
    if (x >= rect->x && x < (rect->x + rect->w))
    {
        /* Check Y coordinate is within rectangle range */
        if (y >= rect->y && y < (rect->y + rect->h))
        {
            /* X and Y is inside the rectangle */
            return 1;
        }
    }

    /* X or Y is outside the rectangle */
    return 0;
}

Upvotes: 1

Alink
Alink

Reputation: 394

Shorter version. Note the use of strict inequality for width and height. I also prefer to visualize the 2 corners, instead of as 2 intervals. 

int in_rect(int x, int y, struct SDL_Rect *r) {
    return (x >= r->x) && (y >= r->y) &&
           (x < r->x + r->w) && (y < r->y + r->h);
}

Upvotes: 0

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