Refactor GUI/Window utils out of gfx library (#1649)

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 122 insertions, 0 deletions

diff --git a/tools/graphics-app-framework/window.h b/tools/graphics-app-framework/window.h
new file mode 100644
index 000000000..e6f886f42
--- /dev/null
+++ b/tools/graphics-app-framework/window.h
@@ -0,0 +1,122 @@
+// window.h
+#pragma once
+
+#include <stdint.h>
+
+namespace gfx {
+
+struct Window;
+
+enum class KeyCode
+{
+    Unknown,
+
+    // TODO: extend this to cover at least a standard US-English keyboard
+
+    A, B, C, D, E, F, G, H, I, J,
+    K, L, M, N, O, P, Q, R, S, T,
+    U, V, W, X, Y, Z,
+
+    Space,
+};
+
+enum class EventCode : uint32_t
+{
+    MouseDown,
+    MouseUp,
+    MouseMoved,
+    KeyDown,
+    KeyUp,
+};
+
+struct Event
+{
+    EventCode   code;
+    Window*     window;
+    union
+    {
+        struct
+        {
+            float x;
+            float y;
+        } mouse;
+
+        KeyCode key;
+    } u;
+};
+
+typedef void (*EventHandler)(Event const&);
+
+struct WindowDesc
+{
+    char const* title = nullptr;
+    void* userData = nullptr;
+    int width = 0;
+    int height = 0;
+    EventHandler eventHandler = nullptr;
+};
+
+Window* createWindow(WindowDesc const& desc);
+void showWindow(Window* window);
+
+void* getPlatformWindowHandle(Window* window);
+void* getUserData(Window* window);
+
+/// Opaque state provided by platform for a running application.
+typedef struct ApplicationContext ApplicationContext;
+
+/// User-defined application entry-point function.
+typedef void(*ApplicationFunc)(ApplicationContext* context);
+
+/// Dispatch any pending events for application.
+///
+/// @returns `true` if application should keep running.
+bool dispatchEvents(ApplicationContext* context);
+
+/// Exit the application with a given result code
+void exitApplication(ApplicationContext* context, int resultCode);
+
+/// Log a message to an appropriate logging destination.
+void log(char const* message, ...);
+
+/// Report an error to an appropriate logging destination.
+int reportError(char const* message, ...);
+
+uint64_t getCurrentTime();
+
+uint64_t getTimerFrequency();
+
+/// Run an application given the specified callback and command-line arguments.
+int runApplication(
+    ApplicationFunc     func,
+    int                 argc,
+    char const* const*  argv);
+
+#define GFX_CONSOLE_MAIN(APPLICATION_ENTRY)  \
+    int main(int argc, char** argv) {       \
+        return gfx::runApplication(&(APPLICATION_ENTRY), argc, argv); \
+    }
+
+#ifdef _WIN32
+
+int runWindowsApplication(
+    ApplicationFunc     func,
+    void*               instance,
+    int                 showCommand);
+
+#define GFX_UI_MAIN(APPLICATION_ENTRY)   \
+    int __stdcall WinMain(              \
+        void*   instance,               \
+        void*   /* prevInstance */,     \
+        void*   /* commandLine */,      \
+        int     showCommand) {          \
+        return gfx::runWindowsApplication(&(APPLICATION_ENTRY), instance, showCommand); \
+    }
+
+#else
+
+#define GFX_UI_MAIN(APPLICATION_ENTRY) GFX_CONSOLE_MAIN(APPLICATION_ENTRY)
+
+#endif
+
+} // gfx