graphics-api-hooking

Graphics API Hooking & Rendering

Overview

This skill covers graphics API resources from the awesome-game-security collection, including DirectX, OpenGL, and Vulkan hooking techniques, overlay rendering, and graphics debugging.

Capture paths, hook points, synchronization, latency, and observable artifacts vary by API, driver, compositor, application, and tool version. Verify the active path and use research-rigor before attributing a capture or overlay signal.

README Coverage

• DirectX > Guide
• DirectX > Hook
• DirectX > Tools
• DirectX > Emulation
• DirectX > Compatibility
• DirectX > Overlay
• OpenGL > Guide
• OpenGL > Source
• OpenGL > Hook
• Vulkan > Guide
• Vulkan > API
• Vulkan > Hook
• Cheat > Overlay
• Cheat > Render/Draw
• Cheat > Anti Screenshot
• Anti Cheat > Screenshot
• Anti Cheat > Detection:Overlay

DirectX

DirectX 9

// Key functions to hook
IDirect3DDevice9::EndScene
IDirect3DDevice9::Reset
IDirect3DDevice9::Present

DirectX 11

// Key functions to hook
IDXGISwapChain::Present
ID3D11DeviceContext::DrawIndexed
ID3D11DeviceContext::Draw

DirectX 12

// Key functions to hook
IDXGISwapChain::Present
ID3D12CommandQueue::ExecuteCommandLists

VTable Hooking

// DX11 Example
typedef HRESULT(__stdcall* Present)(IDXGISwapChain*, UINT, UINT);
Present oPresent;

HRESULT __stdcall hkPresent(IDXGISwapChain* swapChain, UINT syncInterval, UINT flags) {
    // Render overlay here
    return oPresent(swapChain, syncInterval, flags);
}

// Hook via vtable
void* swapChainVtable = *(void**)swapChain;
oPresent = (Present)swapChainVtable[8];  // Present is index 8

OpenGL

Key Functions

wglSwapBuffers
glDrawElements
glDrawArrays
glBegin/glEnd (legacy)

Hook Example

typedef BOOL(WINAPI* wglSwapBuffers_t)(HDC);
wglSwapBuffers_t owglSwapBuffers;

BOOL WINAPI hkwglSwapBuffers(HDC hdc) {
    // Render overlay
    return owglSwapBuffers(hdc);
}