Intro

How Chapter 4 works?

1. init()
   1. SDL_Init()
   2. SDL_CreateWindow()
   3. SDL_GetWindowSurface()
2. loadMedia()
   1. put surfaces in SDL_Surface* array( is global variable) with SDL_LoadBMP().
3. start loop untill variable quit is true.
   1. start loop that calls SDL_PollEvent() untill it returns 0.
      1. if SDL_Event.type is SDL_QUIT, quit is true( which means first loop will end).
         • else if SDL_Event.type is SDL_KEYDOWN, choose mapped sruface to key inside SDL_Surface* array( is global variable).
      2. copy screen(Blit) with SDL_BlitSurface() from chosen surface to screen surface.
      3. update window with SDL_UpdateWindowSurface() to refresh and show what we’ve done.
4. close()
   1. free surfacees in SDL_Surface* array( is global varable) with SDL_FreeSurface().
   2. SDL_DestroyWindow()
   3. SDL_Quit()

Function

• nothing new

Struct

• nothing new

Term

(enum(not official))KeyPressSurfaces

• KEY_PRESS_SURFACE_DEFAULT
• KEY_PRESS_SURFACE_UP
• KEY_PRESS_SURFACE_DOWN
• KEY_PRESS_SURFACE_LEFT
• KEY_PRESS_SURFACE_RIGHT
• KEY_PRESS_SURFACE_TOTAL

these enum will have global SDL_Surface* array for having mapped surface.

SDL_Event.type

• SDL_KEYDOWN

SDL_Event.key.keysym.sym

• SDLK_UP
• SDLK_DOWN
• SDLK_LEFT
• SDLK_RIGHT