Windows Font Cache fix (again) (#595)

* Implemented Windows Font Cache fix, I think?

* These don't need to be volatile

loader/src/hooks/WindowsFontCacheFix.cpp

@@ -0,0 +1,46 @@
+#include <Geode/Geode.hpp>
+
+#ifdef GEODE_IS_WINDOWS
+
+using namespace geode::prelude;
+
+// https://github.com/cocos2d/cocos2d-x/blob/5a25fe75cb8b26b61b14b070e757ec3b17ff7791/cocos2dx/platform/win32/CCImage.cpp#L96
+// stop setFont from caching fonts on Windows
+// Windows Font Cache Manager holds on to them after the app has closed
+// Fonts are supposed to be released in the BitmapDC::~BitmapDC() but this doesn't seem to work consistently?
+// Looks like there's a shared instance of BitmapDC, so presumably it's destructed when the app closes?
+
+int __stdcall AddFontResourceWHook(LPCWSTR p0) {
+    return AddFontResourceExW(p0, FR_PRIVATE, 0);
+}
+
+int __stdcall RemoveFontResourceWHook(LPCWSTR p0) {
+    return RemoveFontResourceExW(p0, FR_PRIVATE, 0);
+}
+
+/*
+ * addr is relative to cocos base
+ * patches x86 CALL at addr to call function at newCall
+ */
+static void patchCall(uintptr_t addr, uintptr_t newCall) {
+    ByteVector patch = { 0xE8 }; // CALL near & relative
+    addr += (uintptr_t)geode::base::getCocos();
+    uintptr_t callAddr = newCall - (addr + 5);
+    for (auto i = 0; i < sizeof(int); ++i)
+        patch.push_back(callAddr >> (8 * i));
+    patch.push_back(0x90); // every overwritten instruction happens to be 6 bytes wide
+    (void)Mod::get()->patch(reinterpret_cast<void*>(addr), patch);
+}
+
+$execute {
+
+    // BitmapDC::~BitmapDC
+    patchCall(0xC9A56, (uintptr_t)&RemoveFontResourceWHook);
+
+    // BitmapDC::setFont
+    patchCall(0xCB5BC, (uintptr_t)&RemoveFontResourceWHook);
+    patchCall(0xCB642, (uintptr_t)&AddFontResourceWHook);
+
+};
+
+#endif