diff options
| author | Stefan Hacker <dd0t@users.sourceforge.net> | 2011-03-01 07:19:20 +0300 |
|---|---|---|
| committer | Stefan Hacker <dd0t@users.sourceforge.net> | 2011-03-04 02:48:23 +0300 |
| commit | 05096f71cc2c1286dd3a3bfe7b443b6d52bdf950 (patch) | |
| tree | 317bd037c8b1aba2955b0fb4dbda0fe52e022c3a /overlay/d3d10.cpp | |
| parent | 630d71267d77348199acf4192488231118d982d9 (diff) | |
Add some comments to hooking code
Diffstat (limited to 'overlay/d3d10.cpp')
| -rw-r--r-- | overlay/d3d10.cpp | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/overlay/d3d10.cpp b/overlay/d3d10.cpp index 0057c1bad..34d6b05e5 100644 --- a/overlay/d3d10.cpp +++ b/overlay/d3d10.cpp @@ -587,6 +587,11 @@ void checkDXGIHook(bool preonly) { } extern "C" __declspec(dllexport) void __cdecl PrepareDXGI() { + // This function is called by the Mumble client in Mumble's scope + // mainly to extract the offsets of various functions in the IDXGISwapChain + // and IDXGIObject interfaces that need to be hooked in target + // applications. The data is stored in the dxgi shared memory structure. + if (! dxgi) return; @@ -603,7 +608,7 @@ extern "C" __declspec(dllexport) void __cdecl PrepareDXGI() { memset(&ovi, 0, sizeof(ovi)); ovi.dwOSVersionInfoSize = sizeof(ovi); GetVersionExW(reinterpret_cast<OSVERSIONINFOW *>(&ovi)); - if ((ovi.dwMajorVersion >= 7) || ((ovi.dwMajorVersion == 6) && (ovi.dwBuildNumber >= 6001))) { + if ((ovi.dwMajorVersion >= 7) || ((ovi.dwMajorVersion == 6) && (ovi.dwBuildNumber >= 6001))) { // Make sure this is vista or greater as quite a number of <=WinXP users have fake DX10 libs installed HMODULE hD3D10 = LoadLibrary("D3D10.DLL"); HMODULE hDXGI = LoadLibrary("DXGI.DLL"); @@ -660,6 +665,8 @@ extern "C" __declspec(dllexport) void __cdecl PrepareDXGI() { if (pDevice && pSwapChain) { HMODULE hRef; + // For VC++ the vtable is located at the base addr. of the object and each function entry is a single pointer. Since p.e. the base classes + // of IDXGISwapChain have a total of 8 functions the 8+Xth entry points to the Xth added function in the derived interface. void ***vtbl = (void ***) pSwapChain; void *pPresent = (*vtbl)[8]; if (! GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, (char *) pPresent, &hRef)) { |