Simple IDC script for IDA Pro that prevents the game (XCOM: Terror from the Deep) from going fullscren

XCOM-TFtD_DisableFullscreen.idc

// XCOM-TFtD_DisableFullscreen.idc
// Simple IDC script for IDA Pro that prevents the game (XCOM: Terror from the Deep) from going fullscren

#include <idc.idc>

static main()
{
    auto IDirectDraw7_SetCooperativeLevel = 0x0046587E;

    if (!RunTo(IDirectDraw7_SetCooperativeLevel))
        return 1;

    if (GetDebuggerEvent(WFNE_SUSP, -1) <= 0)
        return 1;

    auto screen_flags_ptr = GetRegValue("ESP");
    screen_flags_ptr = screen_flags_ptr + 0x08;

    auto screen_flags = DbgDword(screen_flags_ptr);
    if (screen_flags != 0x51) // (DDSCL_FULLSCREEN | DDSCL_EXCLUSIVE | DDSCL_ALLOWMODEX)
        return 1;

    PatchDbgByte(screen_flags_ptr, 0x08); // (DDSCL_NORMAL)
    GetDebuggerEvent(WFNE_CONT, 0);

    return 0;
}