Hide menu pictures only inside the menu frames

The hidden-texture list stayed active in a game; a game texture made at the
address of a freed menu picture was skipped (rendering glitches in-game).
Hiding now applies only while the main menu's frame or the in-game options
draw over the menu background.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

src/mods/hud.cpp

@@ -409,10 +409,22 @@ DrawPrimitiveFn g_drawPrimitive = nullptr;
 DrawIndexedPrimitiveFn g_drawIndexedPrimitive = nullptr;
 
 // Textures not drawn (SetHiddenTextures): the surface bound to stage 0 is
-// tracked per thread (each thread draws with its own device calls).
+// tracked per thread (each thread draws with its own device calls). Only
+// inside a frame drawn over the menu background (g_hidingPictures: the main
+// menu's, the options' in a game): the list keeps surfaces the cache may
+// have freed since, and a game texture made at the same address was skipped
+// in the world view (user, 2026-10-21: "rendering glitches ingame").
 constexpr int kHiddenTextureMax = 64;
 std::atomic<void*> g_hiddenTextures[kHiddenTextureMax] = {};
 thread_local void* g_boundTexture = nullptr;
+thread_local int g_hidingPictures = 0;
+
+struct HidingPictures {
+    HidingPictures() { ++g_hidingPictures; }
+    ~HidingPictures() { --g_hidingPictures; }
+    HidingPictures(const HidingPictures&) = delete;
+    HidingPictures& operator=(const HidingPictures&) = delete;
+};
 
 using SetTextureFn = HRESULT(__stdcall*)(void* device, DWORD stage, void* surface);
 SetTextureFn g_setTexture = nullptr;
@@ -425,7 +437,7 @@ HRESULT __stdcall SetTextureTracked(void* device, DWORD stage, void* surface) {
 }
 
 bool BoundTextureHidden() {
-    if (!g_boundTexture) {
+    if (!g_boundTexture || g_hidingPictures == 0) {
         return false;
     }
     for (const auto& hidden : g_hiddenTextures) {
@@ -521,9 +533,11 @@ public:
         Viewport7 frame = {static_cast<DWORD>(dx), 0, kLayoutWidth, 768, previous_.minZ, previous_.maxZ};
         device_ = device;
         g_setViewport(device, &frame);
+        ++g_hidingPictures;
     }
     ~FrameScope() {
         if (device_) {
+            --g_hidingPictures;
             g_setViewport(device_, &previous_);
         }
     }
@@ -872,6 +886,7 @@ int RenderMenuFrame(void* device, bool framed, int (*body)(void* context), void*
     const int width = mods::widescreen::RenderWidth();
     const int dx = framed && width > kLayoutWidth ? (width - kLayoutWidth) / 2 : 0;
     g_menuFrameDx = dx;
+    HidingPictures hiding;
     Viewport7 previous;
     auto getViewport =
         device ? reinterpret_cast<GetViewportFn>((*static_cast<void***>(device))[kVtableGetViewport]) : nullptr;

src/mods/hud.h

@@ -48,8 +48,9 @@ int HandleCanvas(void* event, int (*body)(void* context), void* context);
 int RenderMenuFrame(void* device, bool framed, int (*body)(void* context), void* context);
 int MenuFrameOffsetX();
 
-// Quads drawn with one of these textures (Direct3D surfaces) are left out,
+// Quads drawn with one of these textures (Direct3D surfaces) are left out
-// on every thread, until the list changes (at most 64).
+// inside the frames drawn over the menu background (RenderMenuFrame, the
+// in-game options), until the list changes (at most 64).
 void SetHiddenTextures(void* const* surfaces, int count);
 
 } // namespace mods::hud