cmake, main: work toward introducing alternative UI

We're going to base opentrack derivatives on the same branch. Previously
merges were a living hell. Modularizing the UI code and having
continuously-built executables will do a lot.

First opentrack variant in progress is a TrackHat device for mouse and
scrolling control for people with spine and hand/arm disabilities.

1 files changed, 14 insertions, 0 deletions

diff --git a/gui/init.hpp b/gui/init.hpp
new file mode 100644
index 00000000..d437b084
--- /dev/null
+++ b/gui/init.hpp
@@ -0,0 +1,14 @@
+#pragma once
+
+#include "export.hpp"
+
+#include <functional>
+#include <QWidget>
+
+int OTR_GUI_EXPORT otr_main(int argc, char** argv, std::function<QWidget*()> make_main_window);
+
+template<typename F>
+auto run_application(int argc, char** argv, F&& fun)
+{
+    return otr_main(argc, argv, fun);
+}