sdl2 - SDL2 library wrapper¶
The sdl2
package is a ctypes
-based wrapper around
the SDL2 library. It wraps nearly all publicly accessible structures and
functions of the SDL2 library to be accessible from Python code.
A detailed documentation about the behaviour of the different functions can found within the SDL2 documentation.
Usage¶
You can use sdl2
in nearly exactly the same way as you would do with
the SDL library and C code.
A brief example in C code:
#include <SDL.h>
int main(int argc, char *argv[]) {
int running;
SDL_Window *window;
SDL_Surface *windowsurface;
SDL_Surface *image;
SDL_Event event;
SDL_Init(SDL_INIT_VIDEO);
window = SDL_CreateWindow("Hello World",
SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
592, 460, SDL_WINDOW_SHOWN);
windowsurface = SDL_GetWindowSurface(window);
image = SDL_LoadBMP("exampleimage.bmp");
SDL_BlitSurface(image, NULL, windowsurface, NULL);
SDL_UpdateWindowSurface(window);
SDL_FreeSurface(image);
running = 1;
while (running) {
while (SDL_PollEvent(&event) != 0) {
if (event.type == SDL_QUIT) {
running = 0;
break;
}
}
}
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
Doing the same in Python:
import sys
import ctypes
from sdl2 import *
def main():
SDL_Init(SDL_INIT_VIDEO)
window = SDL_CreateWindow(b"Hello World",
SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
592, 460, SDL_WINDOW_SHOWN)
windowsurface = SDL_GetWindowSurface(window)
image = SDL_LoadBMP(b"exampleimage.bmp")
SDL_BlitSurface(image, None, windowsurface, None)
SDL_UpdateWindowSurface(window)
SDL_FreeSurface(image)
running = True
event = SDL_Event()
while running:
while SDL_PollEvent(ctypes.byref(event)) != 0:
if event.type == SDL_QUIT:
running = False
break
SDL_DestroyWindow(window)
SDL_Quit()
return 0
if __name__ == "__main__":
sys.exit(main())
You can port code in a straightforward manner from one language to the other,
though it is important to know about the limitations and slight differences
mentioned below. Also, PySDL2 offers advanced functionality, which also feels
more ‘pythonic’, via the sdl2.ext
package.
Missing interfaces¶
The following functions, classes, constants and macros of SDL2 are not
available within sdl2
.
SDL_REVISION
andSDL_REVISION_NUMBER
fromSDL_revision.h
SDL_NAME()
fromSDL_name.h
SDL_MostSignificantBitIndex32()
fromSDL_bits.h
- Everything from
SDL_main.h
- Everything from
SDL_system.h
- Everything from
SDL_assert.h
- Everything from
SDL_thread.h
- Everything from
SDL_atomic.h
- Everything from
SDL_opengl.h
- Everything from
SDL_mutex.h
Additional interfaces¶
The following functions, classes, constants and macros are are not part of
SDL2, but were introduced by sdl2
.
-
sdl2.
ALL_PIXELFORMATS
¶ Tuple containing all SDL2 pixel format constants (SDL_PIXELFORMAT_INDEX1LSB, ..., SDL_PIXELFORMAT_RGB565, ...).
-
sdl2.
AUDIO_FORMATS
¶ Set containing all SDL2 audio format constants (AUDIO_U8, AUDIO_S8, ... AUDIO_F32LSB, ... ).
-
sdl2.
rw_from_object
(obj : object) → SDL_RWops¶ Creates a SDL_RWops from any Python object. The Python object must at least support the following methods:
read(length) -> data
length is the size in bytes to be read. A call to len(data) must return the correct amount of bytes for the data, so that len(data) / [size in bytes for a single element from data] returns the amount of elements. Must raise an error on failure.seek(offset, whence) -> int
offset denotes the offset to move the read/write pointer of the object to. whence indicates the movement behaviour and can be one of the following values:
- RW_SEEK_SET - move to offset from the start of the file
- RW_SEEK_CUR - move by offset from the relative location
- RW_SEEK_END - move to offset from the end of the file
If it could not move read/write pointer to the desired location, an error must be raised.
tell() -> int
Must return the current offset. This method must only be provided, if seek() does not return any value.close() -> None
Closes the object(or its internal data access methods). Must raise an error on failure.write(data) -> None
Writes the passed data(which is a string of bytes) to the object. Must raise an error on failure.
Note
The write() method is optional and only necessary, if the passed object should be able to write data.
The returned
sdl2.SDL_RWops
is a pure Python object and must not be freed viasdl2.SDL_FreeRW()
.