SDL_Rect - Defines a rectangular area
typedef struct{ Sint16 x, y; Uint16 w, h; } SDL_Rect;
x, y Position of the upper-left corner of the rectangle w, h The width and height of the rectangle
A SDL_Rect defines a rectangular area of pixels. It is used by SDL_BlitSurface to define blitting regions and by several other video functions.
SDL_BlitSurface, SDL_UpdateRect