Merge branch 'pr710' into r4-hud

runtime/include/host_overlay.h

@@ -46,6 +46,14 @@ void psx_host_overlay_set_draw_cb(PsxHostOverlayDrawFn fn, void *ctx);
 int  psx_host_overlay_has_draw(void);
 void psx_host_overlay_draw(int width, int height);  /* renderer side */
 
+/* ---- Game HUD layer ---------------------------------------------------------
+ * A title's own heads-up display, drawn once per presented frame (real and
+ * generated) under the in-game menu, same thread and GL rules as the overlay
+ * callback above. Set once (title activation) and kept for the session; NULL
+ * unregisters (no wait: the registrant keeps fn and ctx alive for the session). */
+void psx_host_set_hud_draw_cb(PsxHostOverlayDrawFn fn, void *ctx);
+void psx_host_hud_draw(int width, int height);  /* renderer side */
+
 /* ---- P3: input sink -----------------------------------------------------
  * The sink sees every host SDL event first (main thread), in the normal event
  * drain and in the host pause loop. Returning non-zero consumes the event.

runtime/src/gpu_gl_renderer.c

@@ -9931,8 +9931,10 @@ static void gl_swap_with_osd(void) {
             }
             if (ov_image(3, &px, &ow, &oh) && px)
                 gl_draw_osd_image(px, ow, oh, ww, wh, 0, 0, ww, wh);
-            /* In-game overlay provider (host_overlay.h P2), over everything
-             * the host composes; no-op unless one registered. */
+            /* The title's HUD layer, then the in-game overlay provider
+             * (host_overlay.h P2) over everything; each a no-op unless one
+             * registered. */
+            psx_host_hud_draw(ww, wh);
             psx_host_overlay_draw(ww, wh);
         }
     }

runtime/src/host_overlay.c

@@ -101,6 +101,20 @@ void psx_host_overlay_draw(int width, int height) {
     atomic_fetch_sub(&s_draw_inflight, 1);
 }
 
+/* ---- Game HUD layer ------------------------------------------------------- */
+static PsxHostOverlayDrawFn s_hud_fn = NULL;
+static void *s_hud_ctx = NULL;
+
+void psx_host_set_hud_draw_cb(PsxHostOverlayDrawFn fn, void *ctx) {
+    s_hud_ctx = ctx;
+    s_hud_fn = fn;
+}
+
+void psx_host_hud_draw(int width, int height) {
+    PsxHostOverlayDrawFn fn = s_hud_fn;
+    if (fn && width > 0 && height > 0) fn(width, height, s_hud_ctx);
+}
+
 /* ---- P3: input sink -------------------------------------------------------- */
 static PsxHostInputSinkFn s_sink_fn = NULL;
 static void *s_sink_ctx = NULL;