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.

1 files changed, 90 insertions, 6 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);
+}