Modernization/Porting tracking issue

[Ion Agorria]

I open this meta-issue to keep track of all issues identified that are required to solve so the game can be ported to modern 64bits Windows and non-Windows OSes.

Removing incompatible dependencies:

• Embedded Boost removal #42
• Embedded STLport removal #41
• Stop dependency on precompiled libraries like XTools.lib

Code/Building:

• 64 bits support #26
  • Main menu
  • Map loading
  • CI builds
  • Game saving, needs to be fixed on 32bits first (probably we will be storing size_t or pointers which should be handled)
• Modern compilers support
  • GCC/MinGW
  • Clang
  • MSVC #25
• CMake support #13
• Fix Undefined Behavior in code, game relies on some MSVC 2005 UB derived behavior that is not compatible with current compilers generated code
• Replace asm and __asm code with C/C++ equivalent
  • Compare results between asm and current C implementation, untested currently
• Replace Win32 threads and CriticalSection stuff with SDL
• Replace Win32 CreateEvent stuff
  • Workaround: pevents for API wrapper

Windowing/Input:

• Replace Win32 Window with SDL2 window
• Replace input handling with SDL2 input events
• Load game cursors using SDL2
• Use SDL2 window/events in windows builds

Graphics/Renderer:

• AVI animated texture loading, it uses windows codecs which is unavailable in other platforms
  • Workaround: Use another library like ffmpeg for decoding AVIs
• Modern/portable API using renderer #14
  • Workaround: reusing existing DirectX renderer with DX9 wrapper like DXVK
  • Removed CMatrix and D3DX9 math in favor of xmath
  • Sokol GFX and D3D separation by creating separate backend classes
  • Sokol backend feature parity with D3D:
    • 2D rendering
    • Basic meshes
    • Terrain mesh
    • Bump mapping
    • Shadows
• Deprecated dependency on DirectX extensions (d3dx9)
  • Workaround: implement using methods manually in Exodus module

Music/Sound issues:

• PlayOgg module depends on Windows API sound #50
  • Make PlayOgg optional
  • Make Windows API code dependency optional
  • Evaluate SDL2/SDL2-mixer as potential replacement (for playing decoded ogg samples)
  • Remove Windows API dependency
• Sound module depends on DirectX's DirectSound API which is Windows only
  • Make Sound optional
  • Make DirectSound code dependency optional
  • Evaluate SDL2/SDL2-mixer as potential replacement, we may need to handle several audios playing simultaneously + music + voice in background
  • Remove DirectSound dependency

Network:

• Fix network host starting, right now crashes even with DP8
• Game module depends on DirectX's DirectPlay 8 which is deprecated and removed on modern DirectX SDK's, should be replaced with cross-platform compatible lib
  • Make DirectPlay code dependency optional
  • Evaluate SDL2-net as potential replacement
  • Remove DirectPlay dependency
• Gamespy should be removed #49
• Servers list and NAT workaround #89

Other issues:

• Currently Windows binaries are console apps, reenable win32 app and add icon
• Fix save saving/loading
• Bink video codec and files replacement #48
• Handle Windows format paths, most were wrapped using convert_path_resource but some may be missing yet
• Remove "using namespace std;" around code
• Restoring Scripts compilation using XPrm sources to create scripts compiler binary (XPrm.exe) and call it as part of builds if requested
• Math code cleanup and modernization #46
• Replace Win32 file choosing and mission editor dialogs with cross-platform code
  • Evaluate ImGUI as potential candidate once Sokol GFX is integrated
• Alternate 3D formats #92
• Code cleanup, line endings, UTF8, removing binaries #20