# PySDL2 for Pygamers

Care to move to a newer SDL with your Pygame knowledge? Then you should know one thing or two about PySDL2 before hacking code, since it is completely different from Pygame. Do not let that fact scare you away, the basics with graphics and sound are still the same (as they are fundamental), but you will not find many similarities to the Pygame API within PySDL2.

Todo

More details, examples, etc.

## Technical differences

Pygame is implemented as a mixture of Python, C and Assembler code, wrapping 3rd party libraries with CPython API interfaces. PySDL2 in contrast is written in pure Python, using `ctypes` to interface with the C interfaces of 3rd party libraries.

## API differences

### pygame

pygame | sdl2
--- | ---
`init()` | `sdl2.SDL_Init()` where appropriate
`quit()` | `sdl2.SDL_Quit()` where appropriate
`error` | No equivalent
`get_error()` | `sdl2.SDL_GetError()`
`set_error()` | `sdl2.SDL_SetError()`
`get_sdl_version()` | `sdl2.SDL_GetVersion()`
`get_sdl_byteorder()` | `sdl2.SDL_BYTEORDER`
`register_quit()` | No equivalent planned
`encode_string()` | No equivalent planned
`encode_file_path()` | No equivalent planned

### pygame.cdrom

PySDL2 does not feature any CD-ROM related interfaces. They were removed in SDL2 and PySDL2 does not provide its own facilities.

### pygame.Color

You can find a similar class in `sdl2.ext.Color`. It does not feature a `set_length()` or `correct_gamma()` method, though.

### pygame.cursors

PySDL2 does not feature any pre-defined cursor settings at the moment.

### pygame.display

pygame.display | sdl2
--- | ---
`init()` | `sdl2.ext.init()`
`quit()` | `sdl2.ext.quit()`
`get_init()` | `sdl2.SDL_WasInit()`
`set_mode()` | `sdl2.ext.Window`
`get_surface()` | `sdl2.ext.Window.get_surface()`
`flip()` | `sdl2.ext.Window.refresh()`
`update()` | `sdl2.ext.Window.refresh()`
`get_driver()` | `sdl2.SDL_GetCurrentVideoDriver()`
`Info` | No equivalent
`get_wm_info()` | `sdl2.SDL_GetWindowWMInfo()`
`list_modes()` | `sdl2.SDL_GetNumDisplayModes()`
`mode_ok()` | `sdl2.SDL_GetClosestDisplayMode()`
`gl_get_attribute()` | `sdl2.SDL_GL_GetAttribute()`
`gl_set_attribute()` | `sdl2.SDL_GL_SetAttribute()`
`get_active()` | No equivalent
`iconify()` | `sdl2.ext.Window.minimize()`
`toggle_fullscreen()` | `sdl2.SDL_SetWindowFullscreen()`
`set_gamma()` | `sdl2.SDL_SetWindowBrightness()`
`set_gamma_ramp()` | `sdl2.SDL_SetWindowGammaRamp.()`
`set_icon()` | `sdl2.SDL_SetWindowIcon()`
`set_caption()` | `sdl2.ext.Window.title`
`get_caption()` | `sdl2.ext.Window.title`
`set_palette()` | `sdl2.SDL_SetSurfacePalette()`

### pygame.draw

Drawing primitives can be accessed through either the `sdl2.SDL_RenderDraw*()` and `sdl2.SDL_RenderFill*()` functions or the more powerful `sdl2.sdlgfx` module,

### pygame.event

pygame.event | sdl2
--- | ---
`pump()` | `sdl2.SDL_PumpEvents()`
`get()` | `sdl2.SDL_PollEvent()` or `sdl2.ext.get_events()`
`poll()` | `sdl2.SDL_PollEvent()`
`wait()` | `sdl2.SDL_WaitEvent()`
`peek()` | `sdl2.SDL_PeepEvents()`
`clear()` | `sdl2.SDL_FlushEvents()`
`event_name()` | No equivalent
`set_blocked()` | `sdl2.SDL_EventState()`
`get_blocked()` | `sdl2.SDL_EventState()`
`set_allowed()` | `sdl2.SDL_EventState()`
`set_grab()` | `sdl2.SDL_SetWindowGrab()`
`get_grab()` | `sdl2.SDL_GetWindowGrab()`
`post()` | `sdl2.SDL_PeepEvents()`
`Event` | `sdl2.SDL_Event`

### pygame.font

pygame.font | sdl2
--- | ---
`init()` | `sdl2.sdlttf.TTF_Init()`
`quit()` | `sdl2.sdlttf.TTF_Quit()`
`get_init()` | `sdl2.sdlttf.TTF_WasInit()`
`get_default_font()` | No equivalent planned [1]
`get_fonts()` | No equivalent planned [1]
`match_font()` | No equivalent planned [1]
`SysFont` | No equivalent planned [1]
`Font` | No equivalent planned [1]

### pygame.freetype

PySDL2 does not feature direct FreeType support.

### pygame.gfxdraw

PySDL2 offers SDL_gfx support through the `sdl2.sdlgfx` module.

### pygame.image

pygame.image | sdl2
--- | ---
`load()` | `sdl2.sdlimage.IMG_Load()`, `sdl2.ext.load_image()`
`save()` | `sdl2.surface.SDL_SaveBMP()`, `sdl2.sdlimage.IMG_SavePNG()`
`get_extended()` | `sdl2.sdlimage.IMG_isBMP()` et al.
`tostring()` | No equivalent yet
`fromstring()` | No equivalent yet
`frombuffer()` | No equivalent yet

### pygame.joystick

pygame.joystick | sdl2
--- | ---
`init()` | `sdl2.SDL_Init()`
`quit()` | `sdl2.SDL_Quit()`
`get_init()` | `sdl2.SDL_WasInit()`
`get_count()` | `sdl2.joystick.SDL_NumJoysticks()`
`Joystick()` | `sdl2.joystick.SDL_Joystick` and related functions

### pygame.key

pygame.key | sdl2
--- | ---
`get_focused()` | `sdl2.keyboard.SDL_GetKeyboardFocus()`
`get_pressed()` | `sdl2.keyboard.SDL_GetKeyboardState()`
`get_mods()` | `sdl2.keyboard.SDL_GetModState()`
`set_mods()` | `sdl2.keyboard.SDL_SetModState()`
`set_repeat()` | Based on the OS/WM settings, no equivalent
`get_repeat()` | Based on the OS/WM settings, no equivalent
`name()` | `sdl2.keyboard.SDL_GetKeyName()`

### pygame.locals

Constants in PySDL2 are spread across the different packages and modules, depending on where they originate from.

### pygame.mixer

pygame.mixer | sdl2
--- | ---
`init()` | `sdl2.sdlmixer.Mix_Init()`
`quit()` | `sdl2.sdlmixer.Mix_Quit()`
`get_init()` | No equivalent planned
`stop()` | `sdl2.sdlmixer.Mix_HaltChannel()`, `sdl2.sdlmixer.Mix_HaltGroup()`, `sdl2.sdlmixer.Mix_HaltMusic()`
`pause()` | `sdl2.sdlmixer.Mix_Pause()`, `sdl2.sdlmixer.Mix_PauseMusic()`
`unpause()` | `sdl2.sdlmixer.Mix_Resume()`, `sdl2.sdlmixer.Mix_ResumeMusic()`
`fadeout()` | `sdl2.sdlmixer.Mix_FadeOutChannel()`, `sdl2.sdlmixer.Mix_FadeOutGroup()`, `sdl2.sdlmixer.Mix_FadeOutMusic()`
`set_num_channels()` | `sdl2.sdlmixer.Mix_AllocateChannels()`
`get_num_channels()` | `sdl2.sdlmixer.Mix_AllocateChannels()`
`set_reserved()` | `sdl2.sdlmixer.Mix_ReserveChannels()`
`find_channel()` | No equivalent planned
`get_busy()` | `sdl2.sdlmixer.Mix_ChannelFinished()`
`Sound` | `sdl2.sdlmixer.Mix_Chunk`
`Channel` | No equivalent, use the channel functions instead

### pygame.mixer.music

See pygame.mixer.

### pygame.mouse

pygame.mouse | sdl2
--- | ---
`get_pressed()` | `sdl2.mouse.SDL_GetMouseState()`
`get_pos()` | `sdl2.mouse.SDL_GetMouseState()`
`get_rel()` | `sdl2.mouse.SDL_GetRelativeMouseState()`
`set_pos()` | `sdl2.mouse.SDL_WarpMouseInWindow()`
`set_visible()` | `sdl2.mouse.SDL_ShowCursor()`
`get_focused()` | `sdl2.mouse.SDL_GetMouseFocus()`
`set_cursor()` | `sdl2.mouse.SDL_GetCursor()`
`get_cursor()` | `sdl2.mouse.SDL_SetCursor()`

### pygame.movie

No such module is planned for PySDL2.

### pygame.Overlay

You can work with YUV overlays by using the `sdl2.render` module with `sdl2.render.SDL_Texture` objects.

### pygame.PixelArray

You can access pixel data of sprites and surfaces directly via the `sdl2.ext.PixelView` class. It does not feature comparison or extractions methods.

### pygame.Rect

No such functionality is available for PySDL2. Rectangles are represented via `sdl2.rect.SDL_Rect` for low-level SDL2 wrappers or 4-value tuples.

### pygame.scrap

PySDL2 offers basic text-based clipboard access via the `sdl2.clipboard` module. A feature-rich clipboard API as for Pygame does not exist yet.

### pygame.sndarray

No such module is available for PySDL2 yet.

### pygame.sprite

PySDL2 uses a different approach of rendering and managing sprite objects via a component-based system and the `sdl2.ext.Sprite` class. A sprite module as for Pygame is not planned.

### pygame.Surface

pygame.Surface | sdl2
--- | ---
`blit()` | `sdl2.surface.SDL_BlitSurface()`, `sdl2.ext.SpriteRenderSystem`
`convert()` | `sdl2.surface.SDL_ConvertSurface()`
`convert_alpha()` | `sdl2.surface.SDL_ConvertSurface()`
`copy()` | `sdl2.surface.SDL_ConvertSurface()`
`fill()` | `sdl2.surface.SDL_FillRect()`, `sdl2.surface.SDL_FillRects()`, `sdl2.ext.fill()`
`scroll()` | No equivalent planned
`set_colorkey()` | `sdl2.surface.SDL_SetColorKey()`
`get_colorkey()` | `sdl2.surface.SDL_GetColorKey()`
`set_alpha()` | `sdl2.surface.SDL_SetSurfaceAlphaMod()`
`get_alpha()` | `sdl2.surface.SDL_GetSurfaceAlphaMod()`
`lock()` | `sdl2.surface.SDL_LockSurface()`
`unlock()` | `sdl2.surface.SDL_UnlockSurface()`
`mustlock()` | `sdl2.surface.SDL_MUSTLOCK()`
`get_locked()` | `sdl2.surface.SDL_Surface.locked`
`get_locks()` | No equivalent planned
`get_at()` | Direct access to the pixels for surfaces can be achieved via the `sdl2.ext.PixelView` class
`set_at()` | Direct access to the pixels for surfaces can be achieved via the `sdl2.ext.PixelView` class
`get_at_mapped()` | No equivalent planned
`get_palette()` | via `sdl2.surface.SDL_Surface.format` and the `sdl2.pixels.SDL_PixelFormat.palette` attribute
`get_palette_at()` | `sdl2.pixels.SDL_Palette.colors[offset]`
`set_palette()` | `sdl2.surface.SDL_SetSurfacePalette()`
`set_palette_at()` | `sdl2.pixels.SDL_Palette.colors[offset]`
`map_rgb()` | `sdl2.pixels.SDL_MapRGB()`
`unmap_rgb()` | `sdl2.pixels.SDL_GetRGB()`
`set_clip()` | `sdl2.surface.SDL_SetClipRect()`
`get_clip()` | `sdl2.surface.SDL_GetClipRect()`
`subsurface()` | `sdl2.ext.subsurface()`
`get_parent()` | No equivalent yet
`get_abs_parent()` | As for `get_parent`
`get_offset()` | As for `get_parent`
`get_abs_offset()` | As for `get_parent`
`get_size()` | `sdl2.ext.Sprite.size`, `sdl2.surface.SDL_Surface.w`, `sdl2.surface.SDL_Surface.h`
`get_width()` | `sdl2.ext.Sprite.size[0]`, `sdl2.surface.SDL_Surface.w`,
`get_height()` | `sdl2.ext.Sprite.size[1]`, `sdl2.surface.SDL_Surface.h`
`get_rect()` | No equivalent planned
`get_bitsize()` | `sdl2.pixels.SDL_PixelFormat.BitsPerPixel`
`get_bytesize()` | `sdl2.pixels.SDL_PixelFormat.BytesPerPixel`
`get_flags()` | `sdl2.surface.SDL_Surface.flags`
`get_pitch()` | `sdl2.surface.SDL_Surface.pitch`
`get_masks()` | `sdl2.pixels.SDL_PixelFormat.Rmask`, ...
`get_shifts()` | `sdl2.pixels.SDL_PixelFormat.Rshift`, ...
`get_losses()` | `sdl2.pixels.SDL_PixelFormat.Rloss`, ...
`get_bounding_rect()` | No equivalent planned
`get_view()` | `sdl2.ext.PixelView`
`get_buffer()` | `sdl2.ext.PixelView` or `sdl2.surface.SDL_Surface.pixels`

### pygame.surfarray

2D and 3D pixel access can be achieved via the `sdl2.ext.PixelView` class in environments without numpy. Simplified numpy-array creation with direct pixel access (similar to `pygame.surfarray.pixels2d()` and `pygame.surfarray.pixels3d()`) is available via `sdl2.ext.pixels2d()` and `sdl2.ext.pixels3d()`.

### pygame.time

pygame.time | sdl2
--- | ---
`get_ticks()` | `sdl2.timer.SDL_GetTicks()`
`wait()` | `sdl2.timer.SDL_Delay()`
`delay()` | `sdl2.timer.SDL_Delay()`
`Clock` | No equivalent planned

### pygame.transform

The are no transformation helpers in PySDL2 at moment. Those might be implemented later on via numpy helpers, the Python Imaging Library or other 3rd party packages.

### pygame.version

pygame.version | sdl2
--- | ---
`ver` | `sdl2.__version__`
`vernum` | `sdl2.version_info`

Footnotes

[1] | (1, 2, 3, 4, 5) Check https://bitbucket.org/marcusva/python-utils for an easy to use system font detection module