quirks: Force "tucnak" to x11, software renderer, and no framebuffer …

…texture.

It uses rendering and the event loop from different threads, so it upsets
OpenGL and is hard to work around, beyond just falling back to an
all-software rendering path (which means it has to use X11 too).

There is a real SDL2 target for this app, which doesn't have these
limitations, but this gets the SDL 1.2 target working.

Fixes #182.

COMPATIBILITY.md

@@ -47,3 +47,16 @@ directly, so this does not prevent the game from working on Wayland. No
 XWayland needed!
 
 
+## Tucnak (Linux)
+
+There is an SDL2 target for libzia (which tucnak uses for rendering), and you
+should use that in modern times. But if you're on the SDL 1.2 target,
+tucnak tries to render from a background thread, and does its event loop on
+another, so we can't cleanly hook in to make it draw from the main thread.
+
+sdl12-compat will force SDL2 to use X11, software rendering, and no texture
+framebuffer, to avoid using OpenGL, to avoid the threading problems this
+will cause. The app is perfectly usable in this configuration (and largely
+matches how they expected you to use it with SDL 1.2 anyhow).
+
+

src/SDL12_compat.c

@@ -1184,6 +1184,13 @@ static QuirkEntryType quirks[] = {
     {"dosbox_i686", "SDL12COMPAT_USE_KEYBOARD_LAYOUT", "0"},
     {"dosbox_x86_64", "SDL12COMPAT_USE_KEYBOARD_LAYOUT", "0"},
 
+    /* Tucnak's 1.2 target wants to render and run its event loop from
+       background threads, which upsets OpenGL. Force software renderer and
+       x11. If you want Wayland, etc, use tuknak's existing SDL2 target. */
+    {"tucnak", "SDL_VIDEODRIVER", "x11"},
+    {"tucnak", "SDL_RENDER_DRIVER", "software"},
+    {"tucnak", "SDL_FRAMEBUFFER_ACCELERATION", "false"},
+
     /* The 32-bit Steam build only of Multiwinia Quits but doesn't re-Init */
     {"multiwinia.bin.x86", "SDL12COMPAT_NO_QUIT_VIDEO", "1"}
 #else