SDL 2 port

[cxong]

Seems like a big task, need to investigate: http://wiki.libsdl.org/MigrationGuide

Why port?

• SDL 2.x has gone stable
• SDL 1.2.x will gradually see worse support
• There are some features we may benefit from:
  • Multiple windows/displays - maybe one day we can have 8 or 16 split screen local multiplayer! 😆
  • Android/iOS support - we already have an Android port so it's not a big issue, but iOS is a big one. SDL 2.x is under zlib license so iOS ports will be legal 😈
  • Better fullscreen support - not sure what that entails, but sounds nice
  • Basic Drag'n'Drop support - can use in the classic editor for opening .cpn files by dragging them into the window
  • Support joysticks being plugged in/out - always nice

And now the bad news:

• No/poor/unknown support for Haiku, BSD etc. No more toaster ports 😦

[cxong]

Getting a bit ahead of myself; C-Dogs itself is GPL licensed so releasing in app store is impossible anyway.

[cxong]

• Force feedback (Force feedback #172)

[ghost]

A suggestion: Since SDL 2 is still in it's initial phase and the documentation, even the website isn't totally fleshed out, why not wait, until C-Dogs SDL has all the major problems - like non-free graphics - solved?
Until then, I guess there will be SDL2 ports for Haiku and BSD; well, or at least I hope so...

[cxong]

Actually, an important benefit of using SDL2 is that it allows hardware graphics (without going full openGL). The graphics code will still need a lot of rework, but this will make it feasible to do HD graphics at a nice framerate. Pushing millions of pixels between the CPU/GPU every frame is just way too painful otherwise.

[ghost]

About iOS: Isn't C-Dogs itself GPL'd by Ronny Wester?

[cxong]

Yet another reason for SDL2: we can use this: https://github.com/gabomdq/SDL_GameControllerDB with the function SDL_GameControllerAddMappingsFromFile which will give good button names for controllers.

[ghost]

@cxong 👍

Also, SDL2 seems pretty stable now, unlike in 2013.

[carstene1ns]

Well, an actual port with the current features is possible by using the current rendering (doing pixel manipulation, blit to screen) as SDL2 supports it (to be backward compatible). However, as already mentioned, to make use of all the new features (hardware accelerated textures and such) a major re-factoring would be necessary. I would like to keep compatibility for SDL1.2 until that re-factoring happens.
With a bit of cmake-magic and some `#ifdef' stuff, this should be do-able in a day or two.