From 4eb070c653598e6e89a531745c0743af568758b0 Mon Sep 17 00:00:00 2001
From: Andrea Odetti <mariofutire@gmail.com>
Date: Sat, 30 Oct 2021 14:10:14 +0100
Subject: [PATCH] Make ImGui the default SDL2 implementation.

Signed-off-by: Andrea Odetti <mariofutire@gmail.com>
---
 linux.md                                    |  2 +-
 source/frontends/common2/programoptions.cpp |  4 ++--
 source/frontends/common2/programoptions.h   |  2 +-
 source/frontends/sdl/README.md              | 12 ++++--------
 4 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/linux.md b/linux.md
index 2257ded9..2823de5e 100644
--- a/linux.md
+++ b/linux.md
@@ -42,7 +42,7 @@ Audio files can be read via the cassette interface (SDL Version). Just drop a `w
 
 This is your best choice, in particular the ImGui version.
 
-TL;DR: ``sa2 --imgui``
+TL;DR: just run ``sa2``
 
 See [sa2](source/frontends/sdl/README.md) for more details.
 
diff --git a/source/frontends/common2/programoptions.cpp b/source/frontends/common2/programoptions.cpp
index 96ea2b94..245e0a6e 100644
--- a/source/frontends/common2/programoptions.cpp
+++ b/source/frontends/common2/programoptions.cpp
@@ -105,7 +105,7 @@ namespace common2
     sdlDesc.add_options()
       ("sdl-driver", po::value<int>()->default_value(options.sdlDriver), "SDL driver")
       ("gl-swap", po::value<int>()->default_value(options.glSwapInterval), "SDL_GL_SwapInterval")
-      ("imgui", "Render with Dear ImGui")
+      ("no-imgui", "Plain SDL2 renderer")
       ("geometry", po::value<std::string>(), "WxH[+X+Y]")
       ;
     desc.add(sdlDesc);
@@ -132,7 +132,7 @@ namespace common2
       options.useQtIni = vm.count("qt-ini");
       options.sdlDriver = vm["sdl-driver"].as<int>();
       options.glSwapInterval = vm["gl-swap"].as<int>();
-      options.imgui = vm.count("imgui");
+      options.imgui = vm.count("no-imgui") == 0;
 
       if (vm.count("registry"))
       {
diff --git a/source/frontends/common2/programoptions.h b/source/frontends/common2/programoptions.h
index e5f9579b..2f6f75c7 100644
--- a/source/frontends/common2/programoptions.h
+++ b/source/frontends/common2/programoptions.h
@@ -46,7 +46,7 @@ namespace common2
     bool fixedSpeed = false; // default adaptive
 
     int sdlDriver = -1; // default = -1 to let SDL choose
-    bool imgui = false; // use imgui renderer
+    bool imgui = true; // use imgui renderer
     Geometry geometry; // must be initialised with defaults
     int glSwapInterval = 1; // SDL_GL_SetSwapInterval
 
diff --git a/source/frontends/sdl/README.md b/source/frontends/sdl/README.md
index c00efb0d..4fc23ccd 100644
--- a/source/frontends/sdl/README.md
+++ b/source/frontends/sdl/README.md
@@ -2,27 +2,23 @@
 
 This file only lists options not already described in ``-h``.
 
-There are really 2 frontends here, with and without ``ImGui``, which will become the default in the future.
+The default frontend uses SDL2 + ImGui and requires an OpenGL ES2.0 implementation. It is possible to use plain SDL2 and select the renderer (pass ``--no-imgui`` and look at ``-h``).
 
 ## Configuration
 
-The configuration GUI only works with ``--imgui``: otherwise either manually edit the configuration file ``~/.applewin/applewin.conf`` or use ``qapple`` and run ``sa2 --qt-ini``.
+The configuration GUI only works with ImGui: otherwise either manually edit the configuration file ``~/.applewin/applewin.conf`` or use ``qapple`` and run ``sa2 --qt-ini``.
 The format of the configuration file is the same as the Windows Registry of AppleWin.
 
-*Drag & drop* works for floppy disks. With ``--imgui`` it is possible to select which drive they are dropped into (``D&D``).
+*Drag & drop* works for floppy disks. With ImGui it is possible to select which drive they are dropped into (``D&D``).
 If the filename ends with `.yaml`, it will be loaded as a *State* file.
 
 Individual options can be passed via arguments too: ``-c Configuration.Printer_FileName=Printer.txt``.
 
 If you have a modern gamepad where the axes (``LEFTX`` and ``LEFTY``) move in a circle, the emulator will automatically map to a square: use ``--no-squaring`` to avoid this.
 
-## Raspberry Pi
-
-On a Raspberry Pi, one needs the KMS (fake or not). Better performance has been observed with the ``opengles2`` driver (use ``sa2 --sdl-driver 1``).
-
 ## Dear ImGui
 
-With the flag ``--imgui``, the rendering is performed with [Dear ImGui](https://github.com/ocornut/imgui). In this case ``--sdl-driver`` is ignored and a OpenGL ES2.0 implementation is required.
+The rendering is performed with [Dear ImGui](https://github.com/ocornut/imgui).
 
 On a Raspberry Pi, a KMS driver is mandatory and best results are obtained on a Pi4 with FullKMS (full screen via ``F6``).