GUI: allow movement while open; freeze look and block bind capture

Feedback pass on the preview shell:

- Freeze the rendered view explicitly in CreateMove and again at
  FRAME_RENDER_START; CInput was still letting mouse look move the camera.
- Allow normal WASD/jump/duck movement while the GUI is open; strip
  attack/use/impulse/weapon selection so GUI clicks do not fire.
- While bind capture is active, block all game input.
- Esc no longer closes the GUI; it only cancels bind capture. F2 or the
  title-bar X close the preview.
- Interpose SDL_ShowCursor / SDL_SetRelativeMouseMode / warp / window grab so
  the game cannot re-capture or hide the native cursor while the GUI is open.

3 files changed, 120 insertions, 15 deletions

diff --git a/src/gui.cpp b/src/gui.cpp
index 74dd537..923cd4d 100644
--- a/src/gui.cpp
+++ b/src/gui.cpp
@@ -879,12 +879,8 @@ void gui_handle_input() {
     return;
   }
 
-  if (esc_edge) {
-    if (g_capture_card >= 0)
-      g_capture_card = -1;
-    else
-      close_gui();
-  }
+  if (esc_edge && g_capture_card >= 0)
+    g_capture_card = -1;
 
   // Keep the native cursor free even if the game re-grabs it.
   if (sd_set_relative)
@@ -1196,4 +1192,92 @@ void gui_draw() {
 }
 
 bool gui_is_open() { return g_open; }
+bool gui_bind_capture_active() { return g_open && g_capture_card >= 0; }
 QAngle gui_frozen_view() { return g_frozen; }
+
+// ---------------------------------------------------------------------------
+// SDL cursor interposition
+// ---------------------------------------------------------------------------
+// The game re-asserts relative mouse mode / hides the cursor every frame. While
+// the GUI is open, force the opposite so the native cursor stays usable.
+
+static int (*real_show_cursor)(int) = nullptr;
+static int (*real_set_relative)(int) = nullptr;
+static void (*real_warp_mouse)(void *, int, int) = nullptr;
+static void (*real_set_grab)(void *, int) = nullptr;
+
+extern "C" __attribute__((visibility("default"))) int SDL_ShowCursor(int toggle) {
+  if (!real_show_cursor)
+    real_show_cursor = (int (*)(int))dlsym(RTLD_NEXT, "SDL_ShowCursor");
+  if (g_open && toggle != -1) {
+    if (real_show_cursor)
+      real_show_cursor(1);
+    return 1;
+  }
+  return real_show_cursor ? real_show_cursor(toggle) : 0;
+}
+
+extern "C" __attribute__((visibility("default"))) int
+SDL_SetRelativeMouseMode(int enabled) {
+  if (!real_set_relative)
+    real_set_relative =
+        (int (*)(int))dlsym(RTLD_NEXT, "SDL_SetRelativeMouseMode");
+  if (g_open) {
+    if (real_set_relative)
+      real_set_relative(0);
+    return 0;
+  }
+  return real_set_relative ? real_set_relative(enabled) : 0;
+}
+
+extern "C" __attribute__((visibility("default"))) void
+SDL_WarpMouseInWindow(void *window, int x, int y) {
+  if (!real_warp_mouse)
+    real_warp_mouse =
+        (void (*)(void *, int, int))dlsym(RTLD_NEXT, "SDL_WarpMouseInWindow");
+  if (g_open)
+    return;
+  if (real_warp_mouse)
+    real_warp_mouse(window, x, y);
+}
+
+extern "C" __attribute__((visibility("default"))) void
+SDL_SetWindowGrab(void *window, int grabbed) {
+  if (!real_set_grab)
+    real_set_grab =
+        (void (*)(void *, int))dlsym(RTLD_NEXT, "SDL_SetWindowGrab");
+  if (g_open) {
+    if (real_set_grab)
+      real_set_grab(window, 0);
+    return;
+  }
+  if (real_set_grab)
+    real_set_grab(window, grabbed);
+}
+
+static void (*real_set_mouse_grab)(void *, int) = nullptr;
+static void (*real_warp_global)(int, int) = nullptr;
+
+extern "C" __attribute__((visibility("default"))) void
+SDL_SetWindowMouseGrab(void *window, int grabbed) {
+  if (!real_set_mouse_grab)
+    real_set_mouse_grab =
+        (void (*)(void *, int))dlsym(RTLD_NEXT, "SDL_SetWindowMouseGrab");
+  if (g_open) {
+    if (real_set_mouse_grab)
+      real_set_mouse_grab(window, 0);
+    return;
+  }
+  if (real_set_mouse_grab)
+    real_set_mouse_grab(window, grabbed);
+}
+
+extern "C" __attribute__((visibility("default"))) void
+SDL_WarpMouseGlobal(int x, int y) {
+  if (!real_warp_global)
+    real_warp_global = (void (*)(int, int))dlsym(RTLD_NEXT, "SDL_WarpMouseGlobal");
+  if (g_open)
+    return;
+  if (real_warp_global)
+    real_warp_global(x, y);
+}
diff --git a/src/hl2h.cpp b/src/hl2h.cpp
index c0c27af..a0e6b53 100644
--- a/src/hl2h.cpp
+++ b/src/hl2h.cpp
@@ -546,10 +546,23 @@ static void do_move(int seq, float frametime) {
     cmd->viewangles[0] = f.x;
     cmd->viewangles[1] = f.y;
     cmd->viewangles[2] = f.z;
-    cmd->forwardmove = 0.0f;
-    cmd->sidemove = 0.0f;
-    cmd->upmove = 0.0f;
-    cmd->buttons = 0;
+    // Freeze the rendered view explicitly: CInput may not push the modified
+    // command view back to the engine if the client mode returns false.
+    if (g_iface.engine) {
+      QAngle set = f;
+      using SetViewFn = void (*)(void *, QAngle *);
+      vfunc<SetViewFn>(g_iface.engine, 20)(g_iface.engine, &set);
+    }
+    if (gui_bind_capture_active()) {
+      // Bind capture must not move/act in the game while keys are sampled.
+      cmd->forwardmove = 0.0f;
+      cmd->sidemove = 0.0f;
+      cmd->upmove = 0.0f;
+      cmd->buttons = 0;
+    } else {
+      // Movement is allowed while the GUI is open, but not look/attack/use.
+      cmd->buttons &= (IN_JUMP | IN_DUCK);
+    }
     cmd->impulse = 0;
     cmd->weaponselect = 0;
     cmd->weaponsubtype = 0;
@@ -670,12 +683,19 @@ void set_silent_restore(const QAngle &angles) {
 static void hkdFrameStageNotify(void *self, int stage) {
   if (oFrameStageNotify)
     oFrameStageNotify(self, stage);
-  if (stage == 5 && g_silent_restore_pending) {
-    g_silent_restore_pending = false;
-    if (g_iface.engine) {
-      QAngle a = g_silent_restore_angles;
+  if (stage == 5) {
+    if (g_silent_restore_pending) {
+      g_silent_restore_pending = false;
+      if (g_iface.engine) {
+        QAngle a = g_silent_restore_angles;
+        using SetViewFn = void (*)(void *, QAngle *);
+        vfunc<SetViewFn>(g_iface.engine, 20)(g_iface.engine, &a);
+      }
+    }
+    if (gui_is_open() && g_iface.engine) {
+      QAngle f = gui_frozen_view();
       using SetViewFn = void (*)(void *, QAngle *);
-      vfunc<SetViewFn>(g_iface.engine, 20)(g_iface.engine, &a);
+      vfunc<SetViewFn>(g_iface.engine, 20)(g_iface.engine, &f);
     }
   }
 }
diff --git a/src/hl2h.h b/src/hl2h.h
index 11b9014..8a81439 100644
--- a/src/hl2h.h
+++ b/src/hl2h.h
@@ -234,6 +234,7 @@ void menu_force_close();
 void gui_handle_input();
 void gui_draw();
 bool gui_is_open();
+bool gui_bind_capture_active();
 QAngle gui_frozen_view();
 // ISurface pointer (defined in menu.cpp, used for drawing tests)
 struct ISurface;