Merge branch 'backend-selection' into main

- Implement runtime backend selection (Wayland, X11, Cocoa)
- Add native X11 backend with clipboard, keyboard, mouse, and placement
- Integrate multi-backend integration tests running under Weston and Xwayland
- Retain zero-hole struct packing, branchless ALU/LUT primitives, and paced event loop

1 files changed, 48 insertions, 0 deletions

diff --git a/src/wayland/api.h b/src/wayland/api.h
new file mode 100644
index 0000000..8252041
--- /dev/null
+++ b/src/wayland/api.h
@@ -0,0 +1,48 @@
+#ifndef YASL_WAYLAND_API_H
+#define YASL_WAYLAND_API_H
+
+#include "common/backend.h"
+
+struct wayland_display;
+struct wayland_surface;
+
+struct wayland_display *wayland_display_open(struct yasl_loop *loop, const struct yasl_display_spec *spec);
+void wayland_display_close(struct wayland_display *d);
+uint32_t wayland_display_caps(const struct wayland_display *d);
+void wayland_display_dispatch(struct wayland_display *d);
+int wayland_display_dispatch_timeout(struct wayland_display *d, int timeout_ms);
+void wayland_display_flush(struct wayland_display *d);
+int wayland_display_modifiers(const struct wayland_display *d);
+void wayland_display_copy(struct wayland_display *d, enum yasl_selection sel, const char *text);
+void wayland_display_paste(struct wayland_display *d, enum yasl_selection sel, struct wayland_surface *target);
+bool wayland_display_drag_start(struct wayland_display *d, struct wayland_surface *origin, const struct yasl_drag_image *image, const struct yasl_drag_listener *l, void *ud);
+void wayland_display_drag_cancel(struct wayland_display *d);
+struct wayland_surface *wayland_surface_create_toplevel(struct wayland_display *d, const struct yasl_surface_spec *spec);
+struct wayland_surface *wayland_surface_create_popup(struct wayland_surface *parent, const struct yasl_popup_spec *spec);
+bool wayland_surface_popup_reposition(struct wayland_surface *popup, const struct yasl_popup_spec *spec);
+void wayland_surface_destroy(struct wayland_surface *s);
+struct wayland_display *wayland_surface_display(const struct wayland_surface *s);
+void wayland_surface_set_callbacks(struct wayland_surface *s, const struct yasl_surface_cbs *cbs, void *ud);
+void wayland_surface_set_title(struct wayland_surface *s, const char *title);
+void wayland_surface_schedule_redraw(struct wayland_surface *s);
+bool wayland_surface_present(struct wayland_surface *s, const struct yasl_framebuffer *fb, const struct yasl_damage_list *damage);
+bool wayland_surface_input_poll(struct wayland_surface *s, struct yasl_input_event *ev);
+struct yasl_vector2i wayland_surface_size(const struct wayland_surface *s);
+uint32_t wayland_surface_scale_120(const struct wayland_surface *s);
+uint32_t wayland_surface_state(const struct wayland_surface *s);
+struct yasl_timing wayland_surface_timing(const struct wayland_surface *s);
+uint64_t wayland_surface_frame_time_ns(struct wayland_surface *s, uint64_t now);
+void wayland_surface_set_cursor(struct wayland_surface *s, enum yasl_cursor cursor);
+void wayland_surface_set_background_color(struct wayland_surface *s, uint32_t bg);
+const char *wayland_surface_ime_preedit(const struct wayland_surface *s);
+bool wayland_surface_ime_preedit_cursor(const struct wayland_surface *s, int *begin, int *end);
+void wayland_surface_set_ime_caret(struct wayland_surface *s, struct yasl_rect2i caret);
+bool wayland_surface_start_interactive_move(struct wayland_surface *s);
+bool wayland_surface_start_interactive_resize(struct wayland_surface *s, enum yasl_resize_edge edge);
+bool wayland_surface_show_window_menu(struct wayland_surface *s, struct yasl_vector2i pos);
+bool wayland_surface_drag_carry(struct wayland_surface *s, struct yasl_vector2i offset);
+bool wayland_surface_place_under_pointer(struct wayland_surface *s, struct yasl_vector2i at);
+void *wayland_display_get_native_handle(struct wayland_display *d);
+void *wayland_surface_get_native_handle(struct wayland_surface *s);
+
+#endif