1 files changed, 12 insertions, 0 deletions
diff --git a/include/yasl/yasl.h b/include/yasl/yasl.h
index 0c2235a..2574457 100644
--- a/include/yasl/yasl.h
+++ b/include/yasl/yasl.h
@@ -258,14 +258,25 @@ struct yasl_surface_cbs {
 };
 
 /* Display Lifecycle */
+enum yasl_backend {
+    YASL_BACKEND_AUTO = 0,
+    YASL_BACKEND_WAYLAND,
+    YASL_BACKEND_X11,
+    YASL_BACKEND_COCOA,
+};
+
 struct yasl_display_spec {
     const char *app_id;
     const struct yasl_display_cbs *cbs;
     void *ud;
+    /* Zero selects the native backend. An explicit choice never falls back. */
+    enum yasl_backend backend;
 };
 
+/* Return NULL and set errno if the requested backend cannot open. */
 YASL_API struct yasl_display *yasl_display_open(struct yasl_loop *loop,
                                                const struct yasl_display_spec *spec);
+YASL_API enum yasl_backend yasl_display_backend(const struct yasl_display *d);
 YASL_API void yasl_display_close(struct yasl_display *d);
 YASL_API uint32_t yasl_display_caps(const struct yasl_display *d);
 YASL_API void yasl_display_dispatch(struct yasl_display *d);
@@ -285,6 +296,7 @@ struct yasl_surface_spec {
     struct yasl_vector2i size;
     bool fullscreen;
     bool tearing;
+    /* Optional native graphics device. NULL selects CPU pixel presentation. */
     void *graphics_device;
 };