src/SDLWrap_Surface.hpp

   1 #ifndef _SDLWRAP_SURFACE_H_
   2 #define _SDLWRAP_SURFACE_H_
   3
   4 #include <string>
   5
   6 #include "SDL/SDL.h"
   7
   8 #include "ErrorHandler.hpp"
   9
  10 namespace SDLWrap {
  11
  12 /* This class acts as a wrapper around the SDL_Surface structure and defines the functions you would normally use with
  13  * SDL_Surfaces such as SDL_BlitSurface() and also provides useful shortcuts like a constructor that takes a BMP file
  14  * path.
  15  */
  16 class Surface
  17 {
  18     public:
  19         /* When caught it creates an error std::string which it sends to the Error Handler with the
  20          * FATAL_CONSTRUCTOR_ERROR flag, because the lack of a BMP file means the SDL_Surface pointer is set to NULL,
  21          * and you can't blit a NULL surface can you :P ? Also, the game will be using any images it loads, there is
  22          * no substitute for a BMP file. If it can't be used/found, then what's the point, you might not see something
  23          * important/useful. The game needs them.
  24          */
  25         class SurfaceCreationError {};
  26
  27         Surface() { this->me = NULL; } // TODO: In here or in .cpp or initializer list???
  28
  29         /* This constructor constructs a Surface object and uses SDL_LoadBMP to make the Surface hold a bitmap image.
  30          * If the bitmap file fails to load for whatever reason, be it a non existant file or not a BMP file or
  31          * whatever, the constructor will throw a SurfaceCreationError.
  32          *
  33          * The image is originally held in a temporary SDL_Surface, and if the load succeeds then it is copied into
  34          * the class' private SDL_Surface with a call to SDL_DisplayFormat to ensure the surface has the same format as
  35          * the display surface. This way blitting is done as fast as possible since SDL does not have to convert the
  36          * surface every time it wants to blit it.
  37          *
  38          * BmpFilePath is the file path to a bitmap image file.
  39          *
  40          * TODO: The function currently uses SDL_DisplayFormat() which works on 24-bit images and since pretty much all
  41          *       graphics cards these days deal with 32-bit (alpha channel support), using SDL_DisplayFormatAlpha()
  42          *       would be faster. Maybe I should switch to using that?
  43          */
  44         Surface(const std::string BMPFilePath);
  45
  46         /* Destructs a Surface object and frees it.
  47          * That's really all it does... frees the surface.
  48          */
  49         ~Surface();
  50
  51         /* This entire surface gets blitted onto Destination. If this surface is larger than the destinated surace,
  52          * then clipping will occur, as usual removing the bottom-most and right-most parts of the image.
  53          *
  54          * Destination is the Address of the surface on which this surface is to be blitted on.
  55          * The function returns 0 on success, otherwise -1. If any of the two surfaces were in video memory, it returns
  56          * -2, but the Blit() function takes care of that by reloading the surface and re-blitting.
  57          *
  58          *  And... that was the SDL_BlitSurface() function heh. As for Blit() here, it returns a bool to signal success
  59          *  or failure. Probably not gonna use it for anything but debug purposes though...
  60          *
  61          * TODO: Since there will be a lot of repeated code, probably think of letting all Blit()'s call a single Blit()
  62          */
  63         bool Blit(const Surface &Destination);
  64
  65         /* Blits the Surface onto Destination at co-ordinates (X,Y). */
  66         bool Blit(const Surface &Destination, int DestXOffset, int DestYOffset);
  67
  68     public:
  69         SDL_Surface *me; // Declared protected so it can be inherited by the Display and FontSurface classes.
  70
  71     private:
  72         bool RealBlit(const Surface &Destination, SDL_Rect *SourceRect, SDL_Rect *DestRect); // Used internally.
  73         std::string FilePath; // Maybe remove as it'll be stored somewhere else and you'll end up with TONS of them when creating bullets.
  74 };
  75
  76 };
  77
  78 #endif